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The aim of this study was to determine the total polyphenol and flavonoid content, antioxidant properties and fatty acid profile of semi-hard goat cheese ripened in an oil mixture (Mljet's extra virgin olive oil and refined sunflower oil; 50:50) for different time periods. Five batches of cheese were produced, and each batch was divided into three groups: (1) ripening in air (control group), (2) ripening in oil after 10 days of air ripening, (3) ripening in oil after 20 days of air ripening. The cheeses were sampled on days 0, 10, 20, 30, 45 and 60 of ripening. On day 60, the total polyphenol and flavonoid content differed significantly (p<0.05, p<0.01, respectively) between the group 1 (control group) and group 3 as well as between groups 2 and 3. A significant difference (p<0.01) was found in antioxidant activity between the control group and group 3 with two spectrophotometric methods (DPPH - 2,2-diphenyl-1-picryl-hydrazyl; ABTS - 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)). The ripening treatment significantly (p<0.01) influenced the saturated (SFA) and unsaturated fatty acid (UFA) content between the oil-ripened cheeses. The prolonged air ripening prior to the immersion into oil in group 3 cheeses led to a greater water loss, and the formation of a cheese structure that allowed the oil to penetrate, resulting in a higher polyphenol and flavonoid content, antioxidant activity (DPPH) and UFA content (including oleic and linoleic acid) than in group 2. This indicates that the time of immersion influences the bioactive compounds in the cheese and thus, affects the nutritional value of the cheese. [ABSTRACT FROM AUTHOR]

Ultrafiltration is a technique used for concentration of milk in order to produce cheese with more desirable physicochemical and nutritional properties. On the other hand, use of combined starter cultures for cheese production can led to improve the sensory characteristics and overall acceptability of final product. The objective of the present study was to investigate the effect of using different combinations of Lactobacillus helveticus (L. helveticus) and mesophilic starter culture (Lactobacillus lactis ssp. lactis and Lactobacillus lactis ssp. cremoris) on the volatile compounds and sensory characteristics of ultrafiltered white cheese during ripening. Five ultrafiltered white cheeses were produced using mesophilic starter culture and L. helveticus at different ratios (100:0, 75:25, 50:50, 25:75, and 0:100) and kept in refrigerator (9 ± 0.1°C) for 90 days. The related analysis was performed on 1, 30, 60 and 90 days of ripening. The results revealed that an increasing in L. helveticus ratio caused a significant increasing in the Co2, ethanol, ethylene oxide and a (p<0.05). Regarding sensory significant decreasing in the acetone properties, lower scores of body and texture, and higher scores of odor and flavor were assigned to the cheeses produced using higher ratios of (p<0.05). In conclusion, the use of combinations of L. helveticus mesophilic starter culture and L. helveticus at specific ratios (75:25 and 25:75) led to improve the volatile compounds in the final product and production an ultrafiltered cheese with desirable sensory characteristics. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Typically, Swiss-type cheese is made from cow milk. However, in the present work an attempt to expand the sheep supply chain and product offering in this field was made by developing a new type of cheese using Swiss-type cheese technology. The cheese was manufactured under industrial conditions, and fermentations were carried out using freeze-dried commercial starters that are traditionally used in the production of Swiss cheese. Two experimental "Ewiss cheese" (EC) products were produced using raw milk (RM) and pasteurized milk (PM), respectively. Fourteen microbial groups were investigated by plate counts from curd until ripened cheeses. According to microbiological analyses, no statistically significant differences were found between the 2 productions with respect to the group of lactic acid bacteria (LAB). The curds were mainly characterized by mesophilic LAB cocci (7.45 log 10 cfu/g in RM-EC and 7.33 log 10 cfu/g in PM-EC). However, at the end of the ripening period (9 mo), the cheeses exhibited a higher presence of mesophilic LAB rods. Undesired microbiological groups were found only in the curd of raw milk cheese in the range of 104 to 105 cfu/g, but they were reaching undetectable levels by plate count in the cheese at the end of ripening. The RM-EC and PM-EC were characterized by 76% and 68% of DM, respectively. These cheeses contained 29.30% and 34.36% of protein, and 51.31% and 50.38% of fat, respectively. Textural analysis showed differences in terms of hardness, chewiness, and gumminess between the experimental cheeses and Swiss cheese sold on the market. These differences could be attributed to the higher protein content of ewe milk. The main fatty acids in the cheeses were palmitic acid, myristic acid, oleic acid, and capric acid. Among the organic acids, RM-EC had higher concentrations of lactic acid, whereas PM-EC was higher in propionic acid. The ewe cheeses emitted 46 volatile compounds, including acids, aldehydes, ketones, esters, alcohols, and other compounds. The PM-EC was characterized by the main compounds of Swiss-type cheese: acetic acid, butyric acid, ethyl butyrate, ethyl caproate, propanoic acid, and tetramethylpyrazine. Sensory evaluation showed that the new dairy products were generally appreciated, and PM-EC was the most preferred by the judges. This research has enabled the development of new ewe milk products, which could stimulate the valorization of a sector that has been long neglected and still has a large margin of improvement. [Display omitted] [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. The possibility of inclusion of agro-industrial byproducts in the diet of small ruminants represents both an economic and an environmental strategy for reducing waste management by industries and costs of feeding as well as the impact of livestock farming. Large amounts of wastes from the cocoa industry are produced annually, with a considerable part represented by cocoa bean shells, considered a suitable ingredient to be included in the diet of ruminants within the limits established by European legislation. The aim of this study was to assess the effect of including cocoa bean shells in the diet of dairy sheep on the sensory, volatile, and antioxidant properties of cheese. To this purpose, 20 lactating Comisana ewes were randomly assigned to 2 experimental groups: control (CTRL) and cocoa bean shells (CBS), and received alfalfa hay ad libitum and 800 g of conventional (CTRL) or experimental (CBS) concentrate containing 11.7% CBS to partially replace corn and barley of the CTRL concentrate. Bulk milk collected from each group was used to produce a total of 15 cheeses per group, obtained in 5 different days of cheesemaking (3 cheeses a day per group). After 60 d of aging, each cheese of each experimental group was sampled for the analyses. The results on chemical composition revealed a greater content of monounsaturated fatty acids and an increase in the nutritional indices, suggesting a favorable role of cocoa bean shell dietary inclusion on the nutritive value of cheese. The cheese sensory profile was affected by the cocoa bean shell inclusion, with more pronounced appearance, odor, aroma, and taste attributes in the product. The volatile profile showed only a few significant differences, mainly related to the cheese ripening process, and no differences were found in α-tocopherol contents in cheese fat between the 2 groups. Therefore, the inclusion of coca bean shells in the diet of dairy sheep allowed us to obtain a good-quality cheese, without altering the characteristics associated with the typical profiles of sheep cheese. Furthermore, the use of this byproduct could contribute to decreasing feed costs and waste management, representing a good practice for increasing the sustainability of dairy products. [ABSTRACT FROM AUTHOR]

Cotija and Bola de Ocosingo are artisanal ripened cheeses produced in Mexico. Both are made with raw bovine milk from free-grazing cows and with no starter cultures. Unlike culture-based techniques, molecular methods for pathogen detection in food allow a shorter turnaround time, higher detection specificity, and represent a lower microbiological risk for the analyst. In the present investigation, we analyzed 111 cheese samples (95 Cotija and 16 Bola de Ocosingo) by qPCR (TaqMan®) after an enrichment-culture step specific to each foodborne bacterium. The results showed that 100% of the samples were free of DNA from Listeria monocytogenes, Brucella spp., Escherichia coli enterotoxigenic (ETEC), and O157:H7; 9% amplified Salmonella spp. DNA; and 11.7%, Staphylococcus aureus DNA. However, the threshold cycle (Ct) values of the amplified targets ranged between 23 and 30, indicating DNA from non-viable microorganisms. Plate counts supported this assumption. In conclusion, 100% of the cheeses analyzed were safe to consume, and the enrichment step before DNA extraction proved essential to discern between viable and non-viable microorganisms. Hygienic milking, milk handling, cheese manufacturing, and ripening are crucial to achieve an adequate microbiological quality of cheeses made with raw milk. [ABSTRACT FROM AUTHOR]

Most of the biogenic amines are naturally found in fermented foods as a consequence of amino acid decarboxylation. Their formation is ascribable to microorganisms (starters, contaminants and autochthonous) present in the food matrix. The concentration of these molecules is important for food security reasons, as they are involved in food poisoning illnesses. The most frequent amines found in foods are histamine, putrescine, cadaverine, tyramine, tryptamine, phenylethylamine, spermine and spermidine. One of the most risk-prone foods are cheeses, mostly ripened ones, which could easily accumulate amines due to their peculiar manufacturing process and ripening. Cheeses represent a pivotal food in our diet, providing for nutrients such as amino acids, calcium, vitamins and others; thus, since they are widely consumed, it is important to evaluate the presence of toxic molecules to avoid consumers' poisoning. This review aimed to gather general information on the role of biogenic amines, their formation, the health issues and the microorganisms and processes that produce/reduce them, with a focus on their content in different types of cheese (from soft to hard cheeses) and the biotic and abiotic factors that influence their formation or reduction and concentration. Finally, a multivariate analysis was performed on the biogenic amine content, derived from data available in the literature, to obtain more information about the factors influencing their presence in cheeses. [ABSTRACT FROM AUTHOR]

Camembert is a type of surface-mold-ripened soft cheese traditionally produced from cow's milk. Buttermilk, a by-product of butter production with beneficial nutritional and technological properties, is increasingly being used in various applications, including cheesemaking. Therefore, this study aimed to use sweet buttermilk (BM) in combination with milk at concentrations of 10% (w/w) (BM10) and 20% (w/w) (BM20) for the production of Camembert-type cheese. A control cheese made entirely from milk was also produced. The cheese samples underwent a 28-day ripening process during which their composition, acidity, water activity, color, and sensory properties were examined at 1-week intervals. The microstructure of the matured Camembert-type cheese samples was analyzed using scanning electron microscopy (SEM), and their texture was evaluated. The production yield of BM20 cheese (18.03 ± 0.29 kg/100 kg) was lower (p < 0.05) than that of the control (19.92 ± 0.23 kg/100 kg), with BM10 showing the distinctly lowest yield (14.74 ± 0.35 kg/100 kg). The total solid and fat content of BM Camembert-type cheese samples was lower than the control. However, the total protein content in cheese BM20 at the end of the ripening period was the same as that of the control. The changes in acidity in all samples were typical for Camembert cheese, and water activity was high (above 0.92). The sensory properties of all samples were characteristic of the cheese type, while the color of BM cheese samples differed from the control. The microstructure of BM10 and BM20 cheese variants was similar, namely homogenous and less porous compared to the control. In terms of texture, the BM samples had significantly lower hardness, adhesiveness, and gumminess. This study indicates that sweet BM, particularly at a concentration of 20%, may be effectively used in the production of Camembert-type cheese. [ABSTRACT FROM AUTHOR]

Simple Summary: Ochratoxin A (OTA), a nephrotoxic mycotoxin categorized as a possible carcinogenic agent, is a current problem in the cheese manufacturing industry. The main OTA producers are Penicillium nordicum and Penicillium verrucosum. Therefore, we aimed to investigate different cheese ripening phases to hinder OTA production. We elaborated cheese analogues, inoculated both fungal species, and performed two different ripening phases, at 10 and 15 °C. Despite the fact that both were able to grow, they did not express genes related to OTA production, and no OTA was detected during two weeks of ripening. Therefore, we show that, when the first phases of ripening are maintained at <15 °C, the possibility of OTA production is dramatically minimized. This information is of utmost importance for industries to enhance the safety of their cheese products, which positively impacts human health. A lack of control of the technological abiotic parameters apparent during cheese manufacture, including temperature and relative humidity, results in this dairy product being prone to mold contamination. Sometimes, inoculant molds are used to obtain the characteristic sensory properties of this type of product. However, during the maturation process, some unwanted molds can colonize the ripening cheese and produce mycotoxins. Mycotoxigenic molds such as Penicillium nordicum and Penicillium verrucosum can colonize ripened cheeses, contaminating them with ochratoxin A (OTA), a nephrotoxic 2B toxin. Thus, the presence of OTA in cheeses could represent a hazard to consumers' health. This study has evaluated the growth and OTA production of P. nordicum and P. verrucosum on a cheese analogue under simulated ripening conditions of 10 and 15 °C and 0.96 water activity (aw). Ecophysiological, molecular, and analytical tools assessed the mold growth, gene expression, and OTA production under these environmental conditions. Both species were able to effectively colonize the cheese under these ripening conditions. However, neither species expressed the otapks and otanps biosynthetic genes or produced phenotypic OTA. Therefore, these results suggest a relatively low risk of exposure to OTA for consumers of this type of cheese product. The conditions used were thus appropriate for cheese ripening to minimize the potential for contamination with such mycotoxins. An appropriate adjustment of the technological ripening parameters during such cheese manufacture could contribute to OTA-free cheeses. [ABSTRACT FROM AUTHOR]

Microbial communities play a fundamental role in shaping the taste, aroma, and texture of cheeses. They consist of starter and secondary microorganisms. Starters contribute to acid development during cheesemaking, while secondary microbiota play a crucial role in the ripening process. Their diversity is a subject of significant importance, shaped by various factors such as the cheesemaking environment, employed starters, physicochemical conditions, and manufacturing procedures. In this review, we attempted to provide an accurate picture of the microbial communities commonly found in raw milk cheeses and tried to list their origins, factors influencing their existence, and the approaches used for their screening. The research employed information retrieval methods, mainly focusing on specific keywords. We systematically searched various databases for relevant articles and reviews, prioritizing the retrieval of the most recent publications and those deemed most relevant to the objectives of this review. This review disclosed the frequently identified bacterial genera in cheeses, such as Lactococcus and Lactobacillus. In terms of fungi, regularly isolated species included Candida, Kluyveromyces, Saccharomyces, Yarrowia, Goetrichum, among others. Our investigation enabled the unveiling of both the core microbiota shared across diverse cheeses, crucial for cheese fermentation and ripening, and the variable microbiota contributing to the diversity in cheese characteristics. [ABSTRACT FROM AUTHOR]

This study investigated the effects of once‐a‐day (OAD) and twice‐a‐day (TAD) milking strategies on Cheddar cheese properties, within an Irish pasture‐based system. Cheese derived from OAD milk was more yellow, with significantly higher b* values and a significantly higher β‐carotene content. A significantly higher cheese yield also resulted from OAD milk. Compositional data were largely consistent with previously reported results, and no meaningful differences were found in texture, proteolysis, pH, volatile‐organic‐compounds and free‐fatty‐acid profile. Indications are that OAD milking does not negatively impact Cheddar quality, providing valuable insights for those considering milking frequency impacts on this key dairy product. [ABSTRACT FROM AUTHOR]

Summary: The enzymatic activity exhibited by native enterococci could, in turn, result in a reduction in the cheese ripening time. However, they may also carry virulence factors or resistance to antibiotics that prevent their use in food. A total of 69 enterococci isolates were obtained from a Spanish traditional raw goat's milk cheese and identified by Maldi‐Tof/MS. Different enzymatic activities of technological interest were evaluated and the safety of those with greater technological suitability was studied. The strains were identified as E. malodoratus, E. italicus, E. gilvus, E. faecium, E. durans, E. casseliflavus and E. faecalis. Some strains had very high acidifying and proteolytic activities. Most strains had medium or low amino and carboxypeptidase activities and high dipeptidase activities, while esterase activities were medium. A total of 10 strains were selected based on their enzymatic activities. Of these, five showed β‐haemolysin activity, eight showed gelatinase activity and eight produced tyramine. These activities represent virulence factors that could potentially affect food safety. Finally, all selected strains were susceptible to the antibiotics tested. [ABSTRACT FROM AUTHOR]

The aim of this study is to provide an overview of the specificities (milk characteristics, production process, ripening biochemistry, composition, and sensory properties) and novelties of the world-famous traditional cheeses of the Eastern Mediterranean (EM). The EM area is remarkably heterogeneous (11 countries—Egypt, Israel, Lebanon, Syria, Türkiye, Cyprus, Greece, Albania, Montenegro, Bosnia and Herzegovina, and Croatia) in terms of cheese production, but there are some common features that can be associated with EM which are connected to the difficult geoclimaticconditions (hilly terrain and hot summers). Cheesemakers resort to some preservation methods, such as high salt content (in white-brined cheeses), high total solids content (in hard cheeses), the use of hot water in the treatment of the curd (in pasta filata cheeses), the addition of some local herbs with antimicrobial properties, and the use of animal skin sacks for cheese ripening. Due to the high proportion of whey as a by-product, whey is traditionally used in EM for the production of whey cheeses. Preserving the production of traditional EM cheeses is critical to maintaining their cultural significance and meeting the demand of consumers interested in the provenance, craftsmanship, and nutritional value of these unique products. [ABSTRACT FROM AUTHOR]

Adjunct cultures originating from artisanal cheese environments may play an important role in recreating and developing traditional cheese flavours, thanks to their enzymatic activities, involved in different metabolic pathways that occur during cheese ripening. In this work, Ligilactobacillus salivarius SP36, a strain isolated from an old cheese seal, was added as an adjunct culture to the cheese's raw milk, and its effect on the microbiological, physical–chemical and sensory characteristics of the cheese was studied. The use of L. salivarius SP36 in cheese manufacturing had no significant (p > 0.05) effect on the cheese microbiota, gross composition (fat percentage, protein, total solids, moisture and NaCl concentration), colour or texture of the cheese. However, L. salivarius SP36 increased (p < 0.01) the formation of 25 volatile compounds, including 10 esters, 1 aldehyde, 8 alcohols and 6 carboxylic acids. In addition, cheeses made with L. salivarius SP36 received higher scores (p < 0.01) for aroma intensity and quality than control cheeses. L. salivarius SP36 proved to be a good candidate as an adjunct culture for cheesemaking, since it improved the cheese flavour by making it more intense and recovering typical sensorial notes of traditional cheeses. [ABSTRACT FROM AUTHOR]

The cheese ripening period, in which biochemical changes occur under specific temperature and humidity conditions, is crucial for making the finished product marketable. However, the food matrix can become a growth medium for developing spoilage microorganisms and fungi. In dairy factory, contamination of the crust area can be monitored with several wasteful and time-expensive methods, i.e., the use of saline solutions and/or the brushing of cheese wheels. This study investigates the effectiveness of different ozone treatments, 400 ppb, 8 hours (overnight) every other day until the end of ripening, and 300 ppb, 8 hours per day (overnight) for the entire ripening duration compared to control sample in normal atmosphere, in controlling microbial and fungal growth during the ripening of Toma Piemontese PDO cheese. Results showed that ozone treatments significantly affect spoilage microflora, preserving the overall quality parameters (i.e., weight loss, customer value, and greater sensory nuances). [ABSTRACT FROM AUTHOR]

Raw milk cheeses harbor complex microbial communities. Some of these microorganisms are technologically essential, but undesirable microorganisms can also be present. While most of the microbial dynamics and cross-talking studies involving interaction between food-derived bacteria have been carried out on agar plates in laboratory-controlled conditions, the present study evaluated the modulation of the resident microbiota and the changes of metabolite production directly in ripening raw milk cheese inoculated with Listeria innocua strains. Using a proxy of the pathogenic Listeria monocytogenes, we aimed to establish the key microbiota players and chemical signals that characterize Latteria raw milk cheese over 60 days of ripening time. The microbiota of both the control and Listeria-inoculated cheeses was analyzed using 16S rRNA targeted amplicon sequencing, while direct analysis in real time mass spectrometry (DART-HRMS) was applied to investigate the differences in the metabolic profiles of the cheeses. The diversity analysis showed the same microbial diversity trend in both the control cheese and the inoculated cheese, while the taxonomic analysis highlighted the most representative genera of bacteria in both the control and inoculated cheese: Lactobacillus and Streptococcus. On the other hand, the metabolic fingerprints revealed that the complex interactions between resident microbiota and L. innocua were governed by continuously changing chemical signals. Changes in the amounts of small organic acids, hydroxyl fatty acids, and antimicrobial compounds, including pyroglutamic acid, hydroxy-isocaproic acid, malic acid, phenyllactic acid, and lactic acid, were observed over time in the L. innocua-inoculated cheese. In cheese that was inoculated with L. innocua, Streptococcus was significantly correlated with the volatile compounds carboxylbenzaldheyde and cyclohexanecarboxylic acid, while Lactobacillus was positively correlated with some volatile and flavor compounds (cyclohexanecarboxylic acid, pyroxidal acid, aminobenzoic acid, and vanillic acid). Therefore, we determined the metabolic markers that characterize a raw milk cheese inoculated with L. innocua, the changes in these markers with the ripening time, and the positive correlation of flavor and volatile compounds with the resident microbiota. This multi-omics approach could suggest innovative food safety strategies based on the enhanced management of undesirable microorganisms by means of strain selection in raw matrices and the addition of specific antimicrobial metabolites to prevent the growth of undesirable microorganisms. [ABSTRACT FROM AUTHOR]

Preserving microbial ecosystems obtained from traditional cheese-making processes is crucial to safeguarding the biodiversity of microbial cheese communities and thus ensuring that the high flavor quality of traditional cheeses is maintained. Few protocols have been proposed for the long-term storage of microbial consortia. This work aimed to develop preservation methods to stabilize the entire microbial community in smear-ripened cheese without multiplication or isolation. A simplified microbial community, capable of reproducing the metabolic pattern of cheese maturation, was used in three independent cheese productions. Cheese samples were taken before and after the ripening step, mixed with maltodextrin or saline solution, and subjected to different stabilization conditions including freezing and freeze-drying, followed by 1 month of storage. Microbial survival was quantified using the colony-forming unit assay. Differential scanning calorimetry was used to relate the physical events occurring within the samples to the microbial storage stability. Freezing at −80 °C resulted in the lowest loss of culturability (<0.8 log unit), followed by freezing at −20 °C and freeze-drying. The ripening bacteria appeared as the most sensitive microorganisms within the community. Moreover, a successful cheese production using the best-stabilized community showed the possibility of preserving and re-using an entire microbial community of interest. [ABSTRACT FROM AUTHOR]

In the study, five kinds of white cheese produced, one of which was a control sample (CC). According to the amount of curd used in the production of cheese, black mulberry (C1), blackberry (C2), black grape (C3) and raspberry (C4) dried fruit added to the curd at a rate of 2%. The cheeses packed with a vacuum packaging machine and left to ripening for 90 days at 7±1°C. During the ripening period (3rd, 30th, 60th, 90th days) samples were taken from cheeses, sensory analyses were performed, and textural parameters including resilience, hardness, springiness, gumminess, cohesiveness, adhesiveness, and chewiness were determined using texture profile analyses (TPA). It was observed that neither cohesiveness, adhesiveness and springiness parameters of texture profile differed in terms of cheese type, nor important statistical difference was identified (p>0.05), differences regarding the ripening process found out though (p<0.05). [ABSTRACT FROM AUTHOR]

Microencapsulated enzymes have been found to effectively accelerate cheese ripening. However, microencapsulated enzyme release is difficult to control, often resulting in enzyme release during cheese processing and causing texture and flavor defects. This study aims to address this issue by developing aminopeptidase-loaded pH-responsive chitosan microspheres (A-CM) for precise enzyme release during cheese ripening. An aminopeptidase with an isoelectric point (pH 5.4) close to the pH value of cheese ripening was loaded on chitosan microspheres through electrostatic interaction. Turbidity titration measurements revealed that pH 6.5 was optimal for binding aminopeptidase and microspheres, affording the highest loading efficiency of 58.16%. Various characterization techniques, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy confirmed the successful loading of aminopeptidase molecules on the chitosan microspheres. In vitro release experiments conducted during simulated cheese production demonstrated that aminopeptidase release from A-CM was pH responsive. The microspheres retained the enzyme during the coagulation and cheddaring processes (pH 5.5–6.5) and only released it after entering the cheese-ripening stage (pH 5.0–5.5). By loading aminopeptidase on chitosan microspheres, the loss rate of the enzyme in cheese whey was reduced by approximately 79%. Furthermore, compared with cheese without aminopeptidase and cheese with aminopeptidase added directly, the cheeses made with A-CM exhibited the highest proteolysis level and received superior sensory ratings for taste and smell. The content of key aroma substances, such as 2/3-methylbutanal and ethyl butyrate, in cheese with A-CM was more than 15 times higher than the others. This study provides an approach for accelerating cheese ripening through the use of microencapsulated enzymes. [Display omitted] [ABSTRACT FROM AUTHOR]

Brazilian artisanal cheeses have recently gained significant commercial prominence and consumer favor, primarily due to their distinctive sensory attributes and cultural and historical appeal. Many of these cheeses are made with raw milk and undergo a relatively short ripening period, sometimes ranging from 4 to 8 days, though it is usually shorter than the period stated by law. Moreover, there is insufficient evidence regarding the efficacy of a short ripening period in reducing certain zoonotic foodborne pathogens, such as Brucella spp., Coxiella burnetiid, and Mycobacterium bovis (as part of the Mycobacterium tuberculosis complex). Additionally, a literature analysis revealed that the usual ripening conditions of Brazilian artisanal cheeses made with raw milk may be inefficient in reducing the levels of some hazardous bacterial, including Brucella spp., Listeria monocytogenes, coagulase-positive Staphylococcus, Salmonella, and Coxiella burnetti, to the acceptable limits established by law, thus failing to ensure product safety for all cheese types. Moreover, the assessment of the microbiological safety for this type of cheese should be broader and should also consider zoonotic pathogens commonly found in bovine herds. Finally, a standardized protocol for evaluating the effectiveness of cheese ripening must be established by considering its peculiarities. [ABSTRACT FROM AUTHOR]

Research was conducted to investigate if ripened cheese can be manufactured from pasteurized camel milk with calf rennet. A further aim was to examine the texture modifying effect of microbial transglutaminase at different rennet concentrations. Ripened cheese samples were analysed for physical–chemical characteristics including colour, texture and essential amino acids. Results revealed that it is possible to make semi‐hard camel cheese with the use of calf rennet. However, low‐rennet dosage (2.94 IMCU/L) resulted in good textural properties (hardness, springiness) when commercial microbial transglutaminase was used. [ABSTRACT FROM AUTHOR]

Background: Artisanal cheeses usually contain a highly diverse microbial community which can significantly impact their quality and safety. Here, we describe a detailed longitudinal study assessing the impact of ripening in three natural caves on the microbiome and resistome succession across three different producers of Cabrales blue-veined cheese. Results: Both the producer and cave in which cheeses were ripened significantly influenced the cheese microbiome. Lactococcus and the former Lactobacillus genus, among other taxa, showed high abundance in cheeses at initial stages of ripening, either coming from the raw material, starter culture used, and/or the environment of processing plants. Along cheese ripening in caves, these taxa were displaced by other bacteria, such as Tetragenococcus, Corynebacterium, Brevibacterium, Yaniella, and Staphylococcus, predominantly originating from cave environments (mainly food contact surfaces), as demonstrated by source-tracking analysis, strain analysis at read level, and the characterization of 613 metagenome-assembled genomes. The high abundance of Tetragenococcus koreensis and Tetragenococcus halophilus detected in cheese has not been found previously in cheese metagenomes. Furthermore, Tetragenococcus showed a high level of horizontal gene transfer with other members of the cheese microbiome, mainly with Lactococcus and Staphylococcus, involving genes related to carbohydrate metabolism functions. The resistome analysis revealed that raw milk and the associated processing environments are a rich reservoir of antimicrobial resistance determinants, mainly associated with resistance to aminoglycosides, tetracyclines, and β-lactam antibiotics and harbored by aerobic gram-negative bacteria of high relevance from a safety point of view, such as Escherichia coli, Salmonella enterica, Acinetobacter, and Klebsiella pneumoniae, and that the displacement of most raw milk-associated taxa by cave-associated taxa during ripening gave rise to a significant decrease in the load of ARGs and, therefore, to a safer end product. Conclusion: Overall, the cave environments represented an important source of non-starter microorganisms which may play a relevant role in the quality and safety of the end products. Among them, we have identified novel taxa and taxa not previously regarded as being dominant components of the cheese microbiome (Tetragenococcus spp.), providing very valuable information for the authentication of this protected designation of origin artisanal cheese. A8MAe52mDCf21YyaVzbpAB Video Abstract [ABSTRACT FROM AUTHOR]

Lactic acid bacteria (LAB) play an important role in the ripening of cheeses and contribute to the development of the desired profile of aroma and flavor compounds. Therefore, it is very important to monitor the dynamics of bacterial proliferation in order to obtain an accurate and reliable number of their cells at each stage of cheese ripening. This work aimed to identify and conduct a quantitative assessment of the selected species of autochthonous lactic acid bacteria from raw cow's milk cheese by the development of primers and probe pairs based on the uniqueness of the genetic determinants with which the target microorganisms can be identified. For that purpose, we applied real-time quantitative PCR (qPCR) protocols to quantify Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, and Lactococcus lactis subsp. cremoris cells in cheese directly after production and over three-month and six-month ripening periods. While L. lactis subsp. cremoris shows good acidification ability and the ability to produce antimicrobial compounds, L. delbrueckii subsp. bulgaricus has good proteolytic ability and produces exo-polysaccharides, and S. thermophilus takes part in the formation of the diacetyl flavor compound by metabolizing citrate to develop aroma, they all play an important role in the cheese ripening. The proposed qPCR protocols are very sensitive and reliable methods for a precise enumeration of L. delbrueckii subsp. bulgaricus, S. thermophilus, and L. lactis subsp. cremoris in cheese samples. [ABSTRACT FROM AUTHOR]

There is growing interest in using autochthonous lactic acid bacteria (LAB) that provide unique sensory characteristics to dairy products without affecting their safety and quality. This work studied the capacity of three Brazilian indigenous nonstarter LABs (NSLAB) to produce biogenic amines (BAs) and evaluated their effect on the volatile organic compounds (VOCs), microbial LAB communities, and physicochemical profile of short-aged cheese. Initially, the strain's potential for biosynthesis of BAs was assessed by PCR and in vitro assays. Then, a pilot-scale cheese was produced, including the NSLAB, and the microbial and VOC profiles were analyzed after 25 and 45 days of ripening. As a results, the strains did not present genes related to relevant BAs and did not produce them in vitro. During cheese ripening, the Lactococci counts were reduced, probably in the production of alcohols and acid compounds by the NSLAB. Each strain produces a unique VOC profile that changes over the ripening time without the main VOCs related to rancid or old cheese. Particularly, the use of the strain Lacticaseibacillus. paracasei ItalPN16 resulted in production of ester compounds with fruity notes. Thus, indigenous NSLAB could be a valuable tool for the enhancement and diversification of flavor in short-aged cheese. [ABSTRACT FROM AUTHOR]

Background: Autolysis by cellular peptidoglycan hydrolases (PGH) is a well-known phenomenon in bacteria. During food fermentation, autolysis of starter cultures can exert an accelerating effect, as described in many studies on cheese ripening. In contrast, very little is known about autolysis of starter cultures used in other fermentations. Staphylococcus (S.) carnosus is often used in raw sausage fermentations, contributing to nitrate reduction and flavor formation. In this study, we analyzed the influence of PGHs of the strains S. carnosus TMW 2.146 and S. carnosus TMW 2.2525 on their autolytic behavior. The staphylococcal major autolysin (Atl), a bifunctional enzyme with an N-acetylmuramoyl-L-alanine amidase and a glucosaminidase as an active site, is assumed to be the enzyme by which autolysis is mainly mediated. Results: AtlC mutant strains showed impaired growth and almost no autolysis compared to their respective wild-type strains. Light microscopy and scanning electron microscopy showed that the mutants could no longer appropriately separate from each other during cell division, resulting in the formation of cell clusters. The surface of the mutants appeared rough with an irregular morphology compared to the smooth cell surfaces of the wild-types. Moreover, zymograms showed that eight lytic bands of S. carnosus, with a molecular mass between 140 and 35 kDa, are processed intermediates of AtlC. It was noticed that additional bands were found that had not been described in detail before and that the banding pattern changes over time. Some bands disappear entirely, while others become stronger or are newly formed. This suggests that AtlC is degraded into smaller fragments over time. A second knockout was generated for the gene encoding a N-acetylmuramoyl-L-alanine amidase domain-containing protein. Still, no phenotypic differences could be detected in this mutant compared to the wild-type, implying that the autolytic activity of S. carnosus is mediated by AtlC. Conclusions: In this study, two knockout mutants of S. carnosus were generated. The atlC mutant showed a significantly altered phenotype compared to the wild-type, revealing AtlC as a key factor in staphylococcal autolysis. Furthermore, we show that Atl is degraded into smaller fragments, which are still cell wall lytic active. [ABSTRACT FROM AUTHOR]

Consumer demand for plant cheeses is increasing, but challenges of improving both flavor and quality remain. This study investigated the microbiological and physicochemical impact of seed germination and fermentation with Bacillus velezensis and Bacillus amyloliquefaciens on the ripening of plant cheese analogs. Chlorine treatment or addition of Lactiplantibacillus plantarum and Lactococcus lactis controlled microbial growth during seed germination. Lp. plantarum and Lc. lactis also served as starter cultures for the acidification of soy and lupine milk and were subsequently present in the unripened plant cheese as dominant microbes. A cidification also inhibited the growth and metabolic activity of bacilli but Bacillus spores remained viable throughout ripening. During plant cheese ripening, Lc. lactis was inactivated before Lp. plantarum and the presence of bacilli during seed germination delayed Lc. lactis inactivation. Metagenomic sequencing of full-length 16S rRNA gene amplicons confirmed that the relative abundance of the inoculated strains in each ripened cheese sample exceeded 99%. Oligosaccharides including raffinose, stachyose, and verbascose were rapidly depleted in the initial stage of ripening. Both germination and the presence of bacilli during seed germination had impact on polysaccharide hydrolysis during ripening. Bacilli but not seed germination enhanced proteolysis of plant cheese during ripening. In conclusion, the use of germination with lactic acid bacteria in combination with Bacillus spp. exhibited the potential to improve the quality of ripened plant cheeses with a positive effect on the reduction of hygienic risks. IMPORTANCE The development of novel plant-based fermented food products for which no traditional templates exist requires the development of starter cultures. Although the principles of microbial flavor formation in plant-based analogs partially overlap with dairy fermentations, the composition of the raw materials and thus likely the selective pressure on the activity of starter cultures differs. Experiments that are described in this study explored the use of seed germination, the use of lactic acid bacteria, and the use of bacilli to reduce hygienic risks, to acidify plant milk, and to generate taste-active compounds through proteolysis and fermentative conversion of carbohydrates. The characterization of fermentation microbiota by culture-dependent and culture-independent methods also confirmed that the starter cultures used were able to control microbial communities throughout 90 d of ripening. Taken together, the results provide novel tools for the development of plant-based analogs of fermented dairy products. [ABSTRACT FROM AUTHOR]

Cheese mites environment infestations have been recurrent and well‐known for a long time. Nevertheless, studies aiming to evaluate consumption safety have not yet been conducted, causing legislation in many countries to prohibit and destroy this type of product when detected. Here, we evaluated whether feeding upon cheeses ripened with Tyrophagus putrescentiae (Acari: Acaridae) mites would impair the physiological status of non‐immunosuppressed and immunosuppressed (cyclophosphamide‐treated) mice. Our results revealed the absence of any detrimental effects of eating mite‐ripened cheeses, which can support the advancements in the regularisation of cheeses ripened with mites. [ABSTRACT FROM AUTHOR]

The effect of different combinations of starter and non‐starter lactic acid bacteria on the physicochemical, colour, microbiological and sensory characteristics of Castellano cheese was investigated. Five batches of Castellano cheese were produced from pasteurised sheep's milk. Significant differences in pH, titratable acidity, microbial counts and sensory attributes between the cheese batches made with different starter cultures were found. In conclusion, the incorporation of autochthonous non‐starter lactic acid bacteria strains gave cheeses made with pasteurised milk better flavour and aroma characteristics than the batch made only with commercial starter culture. [ABSTRACT FROM AUTHOR]

The increase in cheese production, sale, and consumption due to the settled lives of societies has led to an increase in cheese‐related diseases. It has become essential to better understand cheese‐borne diseases and to develop control measures. In this study, cheese‐related diseases and precautions taken in the Ottoman Empire from the 19th to the 20th centuries were investigated in Ottoman archival sources. Of these documents, cheese spoilage was detected in 12 and cheese‐related disease in 9. Cheeses that caused diseases or disorders in the relevant period were called spoiled cheese. One document states that a person died of a cheese‐borne illness. Cheese poisoning occurs mainly from unsalted, fresh cheeses. It has been determined that tin‐free copper pots were used in cheese production and sales and covered with herbs such as hemlock during maturation. In the relevant period, microbiological and chemical analyses of cheeses in terms of health were carried out in food control laboratories. Since the mercury chloride solution is used to disinfect animal udders, it has been stated that it contaminates the milk used in cheese production. Authorities have requested a boric acid solution (5% boric acid in hot water) instead of this solution for udder disinfection. In the Ottoman Empire, it was requested to take necessary sanitation and hygiene measures to prevent spoilage and cheese‐related diseases in the production areas or sales places of cheese. Clean and tinned containers should be used in cheese production, storage, and sale, and poisonous herbs should not be used during cheese ripening. It was also essential to analyze them in laboratories at internal and external customs. Knowing the precautions taken in the past to prevent the deterioration of food or the occurrence of diseases has led to modern food safety practices being applied today. [ABSTRACT FROM AUTHOR]

Assessing the authenticity of PDO cheeses is an important task because it allows consumer expectations to be fulfilled and guarantees fair competition for manufacturers. A 3-year survey was carried out, analyzing 271 samples of grated Grana Padano (GP) PDO cheese collected on the European market. Previously developed analytical methods based on proteomics approaches were adopted to evaluate the compliance of market samples with selected legal requirements provided by the specification for this cheese. Proteolysis follows highly repeatable pathways in GP cheese due to the usage of raw milk, natural whey starter, and consistent manufacturing and ripening conditions. From selected casein breakdown products, it is possible to calculate the actual cheese age (should be >9 months) and detect the presence of excess rind (should be <18%). Furthermore, due to the characteristic pattern of free amino acids established for GP, distinguishing it from closely related cheese varieties is feasible. Cheese age ranged from 9 to 25 months and was correctly claimed on the label. Based on the amino acid pattern, three samples probably contained defective cheese and there was only one imitation cheese. Few samples (9%) were proven to contain some excess rind. Overall, this survey highlighted that the adopted control parameters can assure the quality of grated GP. [ABSTRACT FROM AUTHOR]

Due to its versatility and shelf stability, process cheese is gaining interest in many developing countries. The main structural component (base) of most processed cheese formulations is young Cheddar cheese that has high levels of intact casein. Exporting natural Cheddar cheese base from the United States to distant overseas markets would require the aging process to be slowed or reduced. As Cheddar cheese ripens, the original structure is broken down by proteolysis and solubilization of insoluble calcium phosphate. We explored the effect of varying rennet levels (we also used a less proteolytic rennet) and application of high-pressure processing (HPP) to Cheddar cheese, as we hoped these treatments might limit proteolysis and concomitant loss of intact casein. To try to retain high levels of insoluble Ca, all experimental cheeses were made with a high-draining pH and from concentrated milk. To compare our intact casein results with current practices, we manufactured a Cheddar cheese that was prepared according to typical industry methods (i.e., use of unconcentrated milk, calf chymosin [higher levels], and low draining pH value [∼6.2]). All experimental cheeses were made from ultrafiltered milk with protein and casein contents of ∼5.15% and 4.30%, respectively. Three (low) rennet levels were used: control (38 international milk clotting units/mL of rennet per 250 kg of milk), and 25% and 50% reduced from this level. All experimental cheeses had similar moisture contents (∼37%) and total Ca levels. Four days after cheese was made, half of the experimental samples from each vat underwent HPP at 600 MPa for 3 min. Cheddar cheese functionality was monitored during aging for 240 d at 4°C. Cheddar cheese base was used to prepare process cheese after aging for 14, 60, 120, 180, and 240 d. Loss tangent (LT) values of cheese during heating were measured by small strain oscillatory rheology. Intact casein levels were measured using the Kjeldahl method. Acid or base titrations were used to determine the buffering capacity and insoluble Ca levels as a percentage of total Ca. The LT max values (an index of meltability) in process cheese increased with aging for all the cheese bases; the HPP treatment significantly decreased LT max values of both base (natural) and process cheeses. All experimental cheeses had much higher levels of intact casein compared with typical industry-make samples. Process cheese made from the experimental treatments had visually higher stretching properties than process cheese made from Cheddar with the typical industry-make procedure. Residual rennet activity was not affected by rennet level, but the rate of proteolysis was slightly slower with lower rennet levels. The HPP treatment of Cheddar cheese reduced residual rennet activity and decreased the reduction of intact casein levels. The HPP treatment of Cheddar cheese resulted in process cheeses that had slightly higher hardness values, lower LT max values, and retained higher storage modulus values at 70°C. We also observed that the other make procedures we used in all experimental treatments (i.e., using a less proteolytic chymosin, using a concentrated cheese milk, and maintaining a high draining pH value) had a major effect on retaining high levels of intact casein. [ABSTRACT FROM AUTHOR]

Bacteriocins may be used as natural preservatives and antibiotic substitutes in various foods. However, the multistep purification process of bacteriocins results in high production costs, which is an obstacle to their commercial use and consumer accessibility. In this study, a bacteriocin-like inhibitory substance (BLIS) from Bacillus spp. isolated from Korean fermented foods was partially purified using the aqueous two-phase system (ATPS). The maximum activity of the BLIS was achieved for ATPS composed of PEG 1000 (15% [w/w])/ammonium sulfate (20% [w/w])/sodium chloride (2% [w/w]), which caused BLIS activity to increase by 3 times with a 99% recovery rate. In particular, B. amyloliquefaciens Y138-6 BLIS exhibited broad antibacterial activity, high resistance to acid-base stress, and excellent thermal stability. This antibacterial substance inhibited the growth of aerobic bacteria and fungi on the walls of cheese and ripening rooms. These antibacterial properties have been shown to increase food safety and have the potential for use as biopreservatives. Moreover, considering that the execution of the ATPS requires only salts and PEG, it is a simple, environmentally friendly, and cost-effective process and may have industrial applications in the recovery of BLIS from fermentation broth. [ABSTRACT FROM AUTHOR]

Karin Kaymagi is a type of Tulum cheese traditionally produced from sheep milk and ripened in tripe following the addition of cream to the curd. In this study, it was traditionally produced by mixing certain proportions of raw sheep and cow milk (100:0, 75:25, 50:50, 25:75, and 0:100). The samples were allowed to ripen, and analyses were made for chemical, biochemical, electrophoretic, sensory, and textural properties at the 3rd, 30th, 60th, and 90th days of ripening. According to the results obtained, both cheese type and ripening time had significant effects on dry matter, fat, protein, salt, salt in dry matter, % lactic acid, pH, ripening rate, NPN ratio, and PPN ratio (P < 0.05). Only cheese type had a remarkable effect on salt in dry matter and fat in dry matter (P < 0.05). The highest lipolysis value was determined in the samples made of sheep milk only (KK2) (P < 0.05). Electrophoretic analysis showed that aS1-casein and ß-casein concentrations decreased until the end of ripening. Sensory analysis denoted that the KK2 sample was appreciated the most based on colour, appearance, structure, taste, and odor scores (P < 0.05). [ABSTRACT FROM AUTHOR]

Cheese is a nutritious dairy product and a valuable commodity. Internationally, cheddar cheese is produced and consumed in large quantities, and it is the main cheese variety that is exported from Australia. Despite its importance, the analytical methods to that are used to determine cheese quality rely on traditional approaches that require time, are invasive, and which involve potentially hazardous chemicals. In contrast, spectroscopic techniques can rapidly provide molecular information and are non-destructive, fast, and chemical-free methods. Combined with partner recognition methods (chemometrics), they can identify small changes in the composition or condition of cheeses. In this work, we combined FTIR and Raman spectroscopies with principal component analysis (PCA) to investigate the effects of aging in commercial cheddar cheeses. Changes in the amide I and II bands were the main spectral characteristics responsible for classifying commercial cheddar cheeses based on the ripening time and manufacturer using FTIR, and bands from lipids, including β'-polymorph of fat crystals, were more clearly determined through changes in the Raman spectra. [ABSTRACT FROM AUTHOR]

This study aimed to assess the effect of salting and ripening conditions on the features of sheep milk, reduced-fat, semi-hard cheese. Eight groups of cheese, with an average fat content of ≅10.5%, moisture on non-fat substances (MNFS) ≅ 56%, a protein-to-fat ratio of 2.9 and pH 5.1, were manufactured and analyzed throughout ripening. The experimental factors were the salting method (brine- or dry-salting), the salt content (control- and reduced-salt) and the ripening temperature sequence (11 or 18 °C at the 3rd and 4th week). Brine-salted cheese exhibited significantly more adequate (p < 0.05) textural and organoleptic characteristics compared to its dry-salted counterpart, i.e., lower hardness, gumminess and adhesiveness, with higher lightness and flavor scores. The mean salt reduction from 2.1 to 1.6% exhibited significant effects (p < 0.05), i.e., increased moisture and MNFS, decreased hardness, gumminess, chewiness and adhesiveness, and increased lightness and meltability of cheese without affecting the microbiological stability or impairing the organoleptic parameters. Ripening at 18 °C at weeks 3–4 significantly increased (p < 0.05) proteolysis and concentrations of lactic and citric acid without affecting meltability, textural or organoleptic features. In conclusion, brine-salting, salt reduction by 20% and the elevation of temperature at a particular ripening period improved the characteristics of this type of reduced-fat sheep milk cheese. [ABSTRACT FROM AUTHOR]

The aim of this paper was to determine the influence of ripening of semi-hard goat cheese in oil (mixture of Mljet's extra-virgin olive oil and refined sunflower oil; 50:50) on its physicochemical composition and sensory properties, as well as to determine the optimal time of immersion of the cheese in oil. Five batches of cheeses were produced, and the cheeses of the same batch were randomly divided into 3 groups according to the ripening method: (1) ripening in air (control group, treatment 1), (2) ripening in oil after 10 d of ripening in air (treatment 2), (3) ripening in oil after 20 d of ripening in air (treatment 3). Cheeses were sampled during ripening at d 0, 10, 20, 30, 45, and 60, and physicochemical analyses were performed. Oil as a ripening medium for cheese prevented water loss from the cheese (groups 2 and 3), and the significantly lowest contents of dry matter, protein, fat, saturated fatty acids (SFA), unsaturated fatty acids (UFA), oleic acid, and salt were found in group 2. Group 3 had the highest contents of fat, SFA, UFA, and oleic acid. Prolonged ripening of the cheese in air before immersion in oil resulted in greater water loss and the formation of such cheese structure that allowed oil to penetrate the cheese. Water retention and oil penetration into the cheese altered the physicochemical composition of the goat cheese, having a significantly positive effect on the sensory characteristics, particularly color, texture, and taste, allowing the cheese to be consumed even when goat milk is not produced due to seasonality. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the influence of different packaging materials [standard foil: BOPP (biaxially oriented polypropylene)/PET (polyester)/PE (polyethylene) for upper layer, and APET (polyethylene terephthalate)/PE for bottom layer; foil 1: PP (polypropylene)/PET/PE/EVOH (ethylene-vinyl alcohol copolymer)/PE upper layer, and PP/PE/EVOH/PE bottom layer; foil 2: PP/PET/PE/EVOH/PE upper layer, and PA (polyamide)/EVOH/PE bottom layer; foil 3: PP/PET/PE upper layer, and PA/EVOH/PE bottom layer; foil 4: PP/PET/PE upper layer, and PA/PE bottom layer; foil 5: PP upper layer, and PP/PP bottom layer] on the quality of 3 different ripening rennet cheeses packed under different modified atmosphere (MAP) conditions as reflected in particular physicochemical, microbiological, and sensorial changes. The changes were monitored during a period of 90 d of storage at 2°C or 8°C. For Gouda cheese, CO 2 content of the headspace of the packages was in the range 35% to 45%, whereas for Maasdamer and Sielski Klasyczny cheeses it was 55% to 65%. Three-way ANOVA showed that the foil type influenced the moisture content of Gouda cheese stored for 90 d at 2°C and for Sielski Klasyczny cheese at 8°C, whereas the moisture content was not dependent on MAP conditions during storage. Moreover, the foil type had a significant effect on free fatty acid changes for Gouda and Sielski Klasyczny cheeses stored at 2°C for 90 d. Sensory attributes changed significantly over storage time at 2°C for all studied cheeses as affected by foil type, whereas there was no effect of MAP conditions. In general, the cheeses packed in standard foil and foil 4 were characterized by the highest values of mean sensory attributes. Time was the most significant factor influencing most changes in physicochemical and sensory attributes of cheeses stored at 2°C and 8°C. The storage temperature did not affect the moisture of the samples during storage. In general, we found an increase in the pH value during storage regardless of storage temperature. It was possible to decrease the thickness of the packaging material from initial 103 and 250 µm (standard foil; lid and bottom, respectively) to 98 and 100 µm (foil 4) without affecting sensory attributes of the product. [ABSTRACT FROM AUTHOR]

This mini review deals with some controversial non-starter lactic acid bacteria (NSLAB) species known to be both human and animal pathogens but also health-promoting and probiotic. The focus is on Lactococcus garvieae, two Streptococcus species (S. uberis and S. parauberis), four Weissella species (W. hellenica, W. confusa, W. paramesenteroides, and W. cibaria), and Mammalicoccus sciuri, which worldwide, are often found within the microbiotas of different kinds of cheese, mainly traditional artisanal cheeses made from raw milk and/or relying on environmental bacteria for their ripening. Based on literature data, the virulence and health-promoting effects of these bacteria are examined, and some of the mechanisms of these actions are reviewed. Additionally, their possible roles in cheese ripening are also discussed. The analysis of the literature data available so far showed that, in general, the pathogenic and the beneficial strains, despite belonging to the same species, show somewhat different genetic constitutions. Yet, when the safety of a given strain is assessed, genomic analysis on its own is not enough, and a polyphasic approach including additional physiological and functional tests is needed. [ABSTRACT FROM AUTHOR]

Production of various traditional dairy products, particularly cheese, has a long history in Montenegro. White-brined cheeses are the most well-known. One of them is Kučki cheese, with distinct flavor and higher level of proteolysis. The aim of this research was to analyze the proteolysis process during ripening of Kučki cheese. The cheese is produced using traditional technology. FTIR Spectrophotometry was used to calculate the amount of total protein in cheese (IDF141C: 2000). The degree of proteolysis was determined by SDS PAGE (Laemmli, 1970). The cheese was examined for their water-soluble nitrogen (WSN) content using Kuchroo and Fox's method from 1982, as well as their 5% phosphotungstic acid soluble nitrogen (PTAN) content using Stadhouser's method from 1960. The results were expressed as percentages of WSN and PTAN of the total nitrogen matter (WSN/TN and PTAN/TN), as well as PTAN as a percentage of WSN (PTAN/WSN). All analyses were done on 10th, 20th and 30th day of cheese ripening. Four samples of cheese were analyzed for each ripening period. The content of proteins increased during the ripening period. The parameters that determine the process of proteolysis increased during the first 30 days of ripening. The WSN/TN ranged from 13.33 to 44.32%. Also, PTAN/WSN varied from 3.79 to 21.57%. The initial results show that uneven ripening conditions have a direct impact on how proteolytic changes develop throughout ripening. Due to the absence of established cheese-making procedures, Kučki cheese has a considerable degree of heterogeneity in their protein content and proteolysis parameters. However, it is not possible to strictly define the optimal values of the degree of ripening for Kučki cheese. In order to reach certain conclusions, it is necessary to carry out further studies focusing on analyzing a larger number of samples. [ABSTRACT FROM AUTHOR]

This study investigated the potential bioactive properties of white cheeses produced in different regions of Turkey, including their potential antioxidant, antihypertensive, antidiabetic, antimicrobial, and anticancer activities. The cheese samples were analyzed both before and after in vitro digestion. The study found that all cheese samples exhibited significant angiotensin‐converting enzyme inhibition activity both before (45.5%–70.1% for 0.03 g cheese/mL) and after in vitro digestion (25.5%–63.5% for 0.0167 g cheese/mL), whereas α‐amylase inhibition activity was present in all samples (in the range of 5.1%–50.0% for 3.0 × 10−5 g cheese/mL) but disappeared after digestion, and α‐glucosidase inhibition activity was only detected after in vitro digestion (from 20.5% to 60.4% for 5.6 × 10−5 g cheese/mL), indicating potential antidiabetic properties. However, antimicrobial and anticancer activities were not observed in any of the samples. The results also suggest that the bioactivity potential of white cheese may vary depending on the region of production, as cheeses from the Marmara region exhibited high α‐glucosidase inhibition activity after digestion. In conclusion, while white cheese is a valuable addition to the diet due to its high nutritional value and potential health benefits. This study revealed the bioactive potential of ripened white cheese and in vivo investigations of the cheese components would better show their possible benefits. Practical Application: Although the bioactivity potentials varied among the ripened white cheese samples produced in different regions of Turkey, a consistent trend was observed in terms of their presence or absence. Our research revealed that all ripened cheese samples demonstrated significant potential antioxidant and antihypertensive activities, as well as potential antidiabetic properties. Moreover, it can be interpreted that ripened white cheese has the potential to reduce the digestion of carbohydrates when consumed with carbohydrate‐rich foods. Although the present results provide limited practical findings directly applicable to the industry, if the data and information obtained from this study are further explored and further studies delving into specific mechanisms of bioactive components could emerge. [ABSTRACT FROM AUTHOR]

Lactococcus lactis is a key strain in the production of branched-chain aldehydes that contribute to the nutty flavor in cheese. It has been hypothesized that the conversion of branched-chain amino acids (BCAAs) into branched-chain aldehydes is under the regulation of a global transcriptional regulator, CodY; however, the functions remain unclear. This study aimed to elucidate the regulatory effect of CodY on the key genes for the BCAAs conversion into branched-chain aldehydes in L. lactis, namely branched-chain aminotransferase (encoded by bcaT) a-keto acid decarboxylase (encoded by kdcA) and a-keto acid dehydrogenase (encoded by pdhABCD). The deletion of codY was associated with a significant increase in the production of 3-methylbutanal and 2-methylbutanal, indicating the inhibitory effect of CodY on the BCAAs conversion into branched-chain aldehydes. Real-time quantitative reverse transcription-PCR demonstrated the negative regulatory effect of CodY on bcaT and kdcA, whereas pdhABCD was activated by CodY. Potential CodY binding sites in the promoter regions of bcaT, kdcA, and pdhABCD were predicted, and four CodY-boxes within the regulatory regions were verified by electrophoretic mobility shift assay and DNase I footprinting assay. The sites located within the promoter of bcaT and kdcA led to repression by CodY. When one site was located upstream and the other was located within the promoter of pdhABCD, the ultimate effect was activation. Overall, the study revealed that CodY, together with isoleucine, acts as a pleiotropic transcriptional regulator of the conversion of BCAAs into branched-chain aldehydes in L. lactis via binding to various regulatory regions of key genes. IMPORTANCE Branched-chain aldehydes are the primary compounds that contribute to the nutty flavor in cheddar cheese. Lactococcus lactis, which is often applied as primary starter culture, is a significant contributor to the nutty flavor of cheddar cheese due to its ability of conversion of BCAAs into branched-chain aldehydes. In the present study, we found that the regulatory role of CodY is crucial for the conversion. CodY acts as a pleiotropic transcriptional regulator via binding to various regulatory regions of key genes. The results presented valuable knowledge into the role of CodY on the regulation and biosynthetic pathway of branched-chain amino acids and the related aldehydes. Furthermore, it provided new insight for increasing the nutty flavor produced during the manufacture and ripening of cheese. [ABSTRACT FROM AUTHOR]

The microbial ecology fundamentals of raw milk and long-ripened cheeses consist of a complex interaction between starter lactic acid bacteria (SLAB) and non-starter LAB (NSLAB). Although NSLAB aromatic properties are paramount, other phenotypic traits need to be considered for their use as adjunct cultures, such as the capability to endure technological parameters encountered during cheesemaking. The present study focused on the isolation and characterization of NSLAB from spontaneously fermented raw cow's milk coming from 20 dairies that produce Grana Padano PDO cheese. From 122 isolates, the screening process selected the 10 most diverse strains belonging to Lacticaseibacillus spp. to be phenotypically characterized. The strains were tested for their growth performance in milk in combination with the application of technological stresses, for their ability to produce volatile compounds after their growth in milk, and for their ability to use different nutrient sources and resist chemicals. The complex characterization qualified the strains 5959_Lbparacasei and 5296_Lbparacasei as the best candidates to be used as adjunct strains in the production of raw milk and long-ripened cheeses, provided that antibiotic resistance is measured before their employment. Other strains with interesting aromatic capabilities but lower heat resistance were 5293_Lbparacasei, 5649_Lbparacasei and 5780_Lbparacasei, which could be candidates as adjunct strains for uncooked cheese production. [ABSTRACT FROM AUTHOR]

Highly nutritious dairy products such as hard cheeses are considered a good source of protein, fats, mineral substances, and vitamins and are consumed in significant quantities. At the same time, the disadvantages of cheeses include the presence of a large amount of saturated fatty acids in their composition, which are associated with the development of cardiovascular diseases. Therefore, modifying the composition of fatty acids in hard cheese by increasing the content of unsaturated fatty acids and reducing the amount of saturated fatty acids is extremely important for consumers' health. This research aimed to determine the dynamics of microbiological indicators in the ripening technology of hard rennet cheese with different contents of flax seeds as a source of omega-3 fatty acids. The technology of hard rennet cheese with 3-5% flax seed content was investigated. A 1.3 times higher content of lactic acid microflora was found in samples of hard cheese with 5% flax seeds during the first 10 days of ripening compared to the control sample of cheese. On the 60th day of ripening of cheese with a content of 5% flax seeds, the number of lactic acid bacteria was 9.4 ±0.3×109 CFU/g, and in the control cheese – 7.8 ±0.3×109 CFU/g. During the production and ripening of cheese with different content of flax seeds, no exceedance of normative values was found for the number of Enterobacteriaceae and Staphylococcus aureus bacteria. A method (washing the seeds in a sodium bicarbonate solution and drying at a temperature of 95 ±1 for 20 min) of processing flax seeds before adding them to the cheese mass was proposed, which reduced the number of mesophilic microorganisms by approximately 200 times to 3.9 ±0.1×101 CFU/ g, fungi by 160 times to 0.3 ±0.1×101 CFU/g and aerobic mesophilic bacilli by 78 times to 1.1 ±0.1×101 CFU/g. Therefore, the developed hard rennet cheese with flax seeds can be consumed as an additional source of omega-3 fatty acids and dietary fiber.

Preserving microbial ecosystems obtained from traditional cheese-making processes is crucial to safeguarding the biodiversity of microbial cheese communities and thus ensuring that the high flavor quality of traditional cheeses is maintained. Few protocols have been proposed for the long-term storage of microbial consortia. This work aimed to develop preservation methods to stabilize the entire microbial community in smear-ripened cheese without multiplication or isolation. A simplified microbial community, capable of reproducing the metabolic pattern of cheese maturation, was used in three independent cheese productions. Cheese samples were taken before and after the ripening step, mixed with maltodextrin or saline solution, and subjected to different stabilization conditions including freezing and freeze-drying, followed by 1 month of storage. Microbial survival was quantified using the colony-forming unit assay. Differential scanning calorimetry was used to relate the physical events occurring within the samples to the microbial storage stability. Freezing at −80 °C resulted in the lowest loss of culturability (

Kinnow peel oil has been reported to possess antimicrobial and antioxidant activities due to presence of many bioactive compounds. Therefore, the experiments reported in this research paper aimed to investigate the shelf stability and antioxidant potential of Cheddar cheese coated with Kinnow peel oil at various concentrations (0.2%, 0.4%, and 0.6%). The physicochemical characteristics, microbial counts, antioxidant potential, and sensory acceptability of Cheddar cheese were evaluated during ripening (up to 9 months, 4°C). The titratable acidity (%), pH, moisture (%), fat (%), protein contents (%), and soluble nitrogen (SN, %) of Cheddar cheese investigated in the present study showed significant p < 0.05 variations among treatments during ripening. The maximum plate counts (8.36 Log cfu·g−1) were observed in control cheese (T0) ripened for 3 months whereas T3 (9 months ripened) showed the minimum counts (5.04 Log cfu·g−1) among all the treatments. The maximum (3.76 Log cfu·g−1) yeast and mold counts were observed in T0 cheese ripened for 9 month whereas the respective samples of T3 showed the lowest values (2.89 Log cfu·g−1) among all the treatments. The surfaces of Cheddar cheese coated with 0.6% Kinnow peel (T3) did not show any visible signs of yeast and molds. The maximum (366.56 mg GAE/100 g) total phenolic contents were observed in T3 ripened for 6 months. The maximum values (1995.02 mM TE/100 g) of DPPH radical scavenging activity were observed in T3 ripened for 6 months. Similarly, T3 obtained the highest sensory scores among all the treatments. Hence, it was concluded that Kinnow peel oil significantly improved antioxidant potential, sensory perception, and shelf stability of Cheddar cheese. [ABSTRACT FROM AUTHOR]

The maturation of a traditional Swedish long-ripened cheese has shown increasing variation in recent years and the ripening time is now generally longer than in the past. While the cheese is reliant on non-starter lactic acid bacteria for the development of its characteristic flavour, we hypothesised that the observed changes could be due to variations in the microbiota composition and number of bacteria in the raw milk used for production of the cheese. To evaluate associations between microbiota in the raw milk and the resulting cheese, three clusters of commercial farms were created to increase variation in the microbiota of dairy silo milk used for cheese production. Cheese production was performed in three periods over one year. Within each period, milk from the three farm clusters was collected separately and transported to the cheese production facility. Following pasteurisation, the milk was processed into the granular-eyed cheese and matured at a dedicated cheese-ripening facility. For each cheese batch, farm bulk and dairy silo milk samples, a starter culture, early process samples and cheese samples from different stages of maturation (7–20 months) were collected and their microbiota characterised using 16S rRNA amplicon sequencing. The microbiota in the farm bulk milk differed significantly between periods and clusters. Differences in microbiota in dairy silo milk were observed between periods, but not between farm clusters, while the cheese microbiota differed between periods and clusters. The top 13 amplicon sequence variants were dominant in early process samples and the resulting cheese, making up at least 93.3% of the relative abundance (RA). Lactococcus was the dominant genus in the early process samples and, together with Leuconostoc, also dominated in the cheese samples. Contradicting expectations, the RA of the aroma-producing genus Lactobacillus was low in cheese during ripening and there was an unexpected dominance of starter lactic acid bacteria even at the later stages of cheese ripening. To identify factors behind the recent variations in ripening time of this cheese, future studies should address the effects of process variables and the dairy environment. [ABSTRACT FROM AUTHOR]

Koji mold, classified in the genus Aspergillus , is used to produce traditional Japanese fermented foods such as miso, soy sauce, and sake. In recent years, the application of koji mold to cheese ripening has attracted attention, and cheese surface-ripened with koji mold (koji cheese) has been studied. In this study, to evaluate the taste characteristics of koji cheese, an electronic tongue system was employed to measure the taste values of cheese samples ripened using 5 strains of koji mold in comparison with commercial Camembert cheese. All koji cheese samples exhibited lower sourness and greater bitterness, astringency, saltiness, and umami richness than the Camembert cheese samples. The intensity of each taste characteristic differed depending on the koji mold strain. These results indicate that koji cheese has a different taste value than conventional mold-ripened cheese. Furthermore, the results also indicate that various taste characteristics can be achieved by selecting different koji molds. [ABSTRACT FROM AUTHOR]

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The milk's natural flora, or the starter, can preserve cheesemaking and allow for microbial competition. This investigation aimed to improve cheese safety and assess its characteristics using probiotic cell pellets (LCP) or cell-free extracts (CFS). Cheese samples were collected from different areas to investigate the current contamination situation. Six CFSs of probiotics were assessed as antifungal against toxigenic fungi using liquid and solid media and their aflatoxin reduction impact. The most effective CFS was chosen for cheese coating in nanoemulsion. Coated cheese with CFS, LCP, and LCP-CFS was assessed against control for changes in chemical composition, ripening indications, rheological properties, and microbiology. Results showed significant contamination levels in the collected samples, and toxic fungi were present. Lactobacillus rhamnosus CFS has aflatoxins reducibility in liquid media. During cheese ripening, uncoated cheese showed higher fat, protein, salt content, soluble nitrogen, total volatile fatty acids, tyrosine, and tryptophan contents than coated samples, except for LCP-coating treatment. Cheese rheology indicated that coating treatments had the lowest hardness, cohesiveness, gumminess, chewiness, and springiness compared to uncoated cheese. Uncoated cheese had the highest yeast and mold counts compared to the treated ones. The LCP-CFS-coated cheese showed no Aspergillus cells for up to 40 days. Uncoated Ras cheese recorded slightly lower flavor, body, texture, and appearance scores than coated cheeses. In conclusion, coating cheese with L. rhamnosus nanoemulsion has antifungal and antiaflatoxigenic properties, even for LCP, CFS, and CFS-LCP, which could extend cheese shelf life. [ABSTRACT FROM AUTHOR]

Blue cheeses are those whose matrix is veined with a blue, blue-grey, or blue-green colour due to the development of Penicillium roqueforti. There are more than 45 varieties of blue cheese produced worldwide, with some distinct features, although the manufacture process is similar. In addition to P. roqueforti, complex microbial populations interact and succeed throughout the manufacturing and ripening at the cheese's surface (the rind) and interior (matrix). The microbiota of blue cheeses is made up of a vast array of both prokaryotic and eukaryotic microorganisms. Acidification of the curd relies on the action of lactococci and other lactic acid bacteria (LAB) species. The ripened cheeses' final quality and shelf-life properties largely depend on the enzymatic systems of the components of the microbiota, particularly on those of LAB, P. roqueforti, and yeast species. Proteolysis is the most complex and important primary biochemical process involved in blue-veined cheeses during ripening, with P. roqueforti being considered the main proteolytic agent. Lipolysis is also strong, originating, among other compounds, ketones, which are the main aroma compounds in blue-veined cheeses. In addition, several bioactive compounds are produced during ripening. The biochemical activities, mainly of microbial origin, are responsible for the sensory characteristics of these very appreciated cheese varieties worldwide. [ABSTRACT FROM AUTHOR]

The present study investigated some physico-chemical and microbiological traits of 20-month ripened hard cheeses produced from low-temperature high-speed centrifuged raw milk that developed a structural defect consisting of eyes or slits in the paste. Cheeses obtained using the same process and that did not develop the defect were used as controls. The colour, texture, moisture, water activity, proton molecular mobility, microstructure, extent of proteolysis, and viable microorganisms have been evaluated in all the cheese samples, and the significant differences between the defective and non-defective cheeses have been critically discussed. At a microstructural level, the defects caused fat coalescence and an unevenly organised protein matrix with small cracks in the proximity of the openings. The different fat organisation was correlated to a different transverse relaxation time of 1H population relaxing at higher times. The textural and colour features were not different from those of the control cheeses and were comparable with those reported in the literature for other long-ripened hard cheeses. On the other hand, the defective cheeses showed a higher moisture level and lower lactobacilli and total mesophilic bacteria concentrations, but the microbial origin of the defect remains an open hypothesis that deserves further investigation. [ABSTRACT FROM AUTHOR]