Search

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]

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]

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]

The naturally occurring microparticles in the cheesemilk are essential for the eye formation in cheeses because they act as eye nuclei. So, their elimination could be a strategy to avoid the eye formation in cheese varieties in which the eyes are considered a defect. The objective of this work was to test the efficiency of a cost‐affordable method, microfiltration through filter bag with 1 μm pore size, for eliminating microparticles from the cheesemilk and so to prevent the undesirable eye formation. For that, cheesemilk was microfiltrated and used to make experimental and control Swiss‐type cheeses with and without the addition of hay microparticles, respectively. These microparticles were added to act as eye nuclei and to promote the eye formation in experimental cheeses, while the absence of microparticles in control cheeses should avoid the eye development. Cheeses were ripened (60 days) in adequate successive steps to allow the gas production by the propionic bacteria included in the starter. Gross composition, pH, and content of carbohydrates and organic acids including propionate were the same in both treatments indicating that similar amounts of CO2 were produced. Despite microfiltration of the milk, control cheeses developed a considerable number of eyes, as well as experimental cheeses, although the eye volume was higher in the last ones. So, the microfiltration with a filter bag was not efficient to prevent eye formation, probably because it did not eliminate all the native nuclei, and therefore is not suitable to our objective. Practical Applications: It have been demonstrated that the presence of microparticles is absolutely needed for the eyes formation because they act as eye nuclei. So, the elimination of these microparticles from the cheesemilk could be a strategy to avoid the unwanted eye formation in some cheese varieties, which is a main problem for small and medium cheese factories. In this way, tangential microfiltration of cheesemilk has been proposed as an appropriate technique to removes naturally occurring microparticles. However, it is a costly method and not entirely widespread. In this work, the performance of a more cost affordable and easily adaptable method: microfiltration through filter bag (not tangential), for eliminating microparticles and so to avoid eye formation in cheese varieties in which the eyes are considered a defect was assessed. However, this methodology did not demonstrate a good performance. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ripened cheeses, such as pecorino, are susceptible to mites and molds contamination on the crust area that must be removed before the product can be marketed. This study investigates the effectiveness of gaseous ozone treatment in the control of microbiological and mite growth without negatively affecting product quality. RESULTS: Cheese samples were treated with gaseous ozone at 200 and 300 ppb for 8 h per day (overnight) for 150 days in storage rooms under controlled conditions (12 °C and 85% relative humidity). The results showed that ozone at 200 ppb limits the growth of mites starting from 25 days of storage and significantly reduced bacteria, molds, and yeasts counts starting from 75 days of storage. Concerning the physicochemical and qualitative parameters evaluated during ripening (weight loss, moisture content, dry weight, ash, fat, protein, total nitrogen, color, non‐destructive firmness), no significant differences were shown between the control samples and ozone treatment at 200 ppb. Sensory analysis (consumer test) also showed no specific defects with the ozone‐treated samples. It was observed that the ozone treatment at 300 ppb had limited microbiological growth and no alteration of sensory aspects but did not have the same positive impact on some aspects of overall quality, compared with ozone treatment at 200 ppb. CONCLUSION: The use of gaseous ozone treatments during ripening of pecorino cheese can potentially offer an excellent solution for the control of mite growth, while preserving the quality and sensory characteristics of the product. For this reason, this technique could be very useful for commercial purposes. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The aldehyde 3‐methylbutanal is a key aroma compound for many types of cheeses. Intracellular enzymes of cheese starter cultures are predominantly responsible for the conversion of leucine into 3‐methylbutanal. Environmental conditions during cheese manufacturing also play a role in the production of 3‐methylbutanal. Our work shows that salting has a detrimental effect on the capacity of Lactococcus lactis subsp. lactis DS84445 to produce 3‐methylbutanal. In that respect, a promising way to control the concentration of 3‐methylbutanal is by using a cheese starter culture that produces the aimed level of 3‐methylbutanal before salting starts and preferably when lactose is still available. [ABSTRACT FROM AUTHOR]

Summary: The effect of simultaneous transglutaminase (TGase) treatment with pectic fat mimetics (PFM) addition on regularity of protein and fat degradation and flavour compound variations in Cheddar cheese during ripening was investigated. In the early stages of fermentation, the cheese with 20% PFM and 15 U/L TGase had a higher amino acid content. In the middle stage of fermentation, cheese with high concentration of TGase hydrolysed more proteins. Cheese supplemented with PFM and TGase showed increased content of long‐chain polyunsaturated fatty acids, especially linoleic acid (C18:2). In addition, PFM and TGase compensated the flavour deficiencies of low‐fat cheeses and had positive effects on volatile compounds such as alcohols, acids and methyl ketones. Overall, the characteristics and flavours of Cheddar cheese with the addition of PFM and TGase were superior to the control group, which could provide a theoretical basis for the application of PFM and TGase in cheese production. [ABSTRACT FROM AUTHOR]

Traditional cheeses which are normally produced from raw milk are very popular due to their intense and unique taste and aroma. However, high microbial contamination of raw milk due to manual milking and secondary contamination may lead to many diseases in humans in Iran. Lighvan is a traditional starter‐free locally made Iranian cheese that is made from raw ewe's milk. Since the use of raw milk in the preparation of cheese produces serious health problems, due to the limited ripening period of this type of cheese, this study aimed to evaluate the feasibility of preparing Lighvan cheese from pasteurized milk. For this purpose, different characteristics of cheese prepared with pasteurized milk were compared with raw milk cheese. The results showed a reduction in the microbial population over the ripening time in both types of cheeses. However, coliforms and Escherichia coli were seen in raw milk cheeses until the last day of ripening. Regarding chemical analyses, the water‐soluble nitrogen fraction and lipolysis products increased during ripening. Moreover, the raw milk cheeses indicated a higher lipolysis index than the pasteurized ones. According to the obtained results from the sensory evaluation, the raw milk cheese indicated higher acceptability compared with the pasteurized milk cheese. However, since the presence of E. coli makes the cheese inedible, it seems that the pasteurization of milk is mandatory for the production of this type of cheese. [ABSTRACT FROM AUTHOR]

Summary: An orange‐coloured carrot pectin‐enriched fraction (CPEF), with 50% uronic acids (42%‐methylated), carrying lipophilic carotenoids and α‐tocopherol, developed homogeneous calcium‐crosslinked films at 0%, 25%, 50%, 75% and 100% CPEF proportions regarding a commercial pectin. CPEF gave higher relative elongation at break (65% for 50% CPEF film) when compared to 0% CPEF film (26% elongation). FTIR spectra showed a decreased intensity in the C = O group of the esterified carboxylate band as the CPEF content increased. CPEF maintained the orange colour (a* ≈ +37) and partly the carotenes (k ≈ 8.62 × 10−3 d−1) in films, even under 25 °C light storage. Also, CPEF gave water resistance to dissolution (100% CPEF film: 50% solubility), maintaining film integrity after 24 h soaking. Surface wettability decreased (40° contact angle) when CPEF proportion increased. These characteristics made the 100% CPEF film an efficient antioxidant interface that preserved a vegan cashew ripened cheese of high water activity (0.952) for 60 days at 7 °C, as determined through the assay of thiobarbituric acid‐reactive substances (TBARS). [ABSTRACT FROM AUTHOR]

Milk proteins are recognized as the main source of biologically active peptides. Casein's primary structure contains several bioactive amino acid sequences on its latent inactive form. These potential active sequences can be released during cheese manufacture and ripening, giving rise to peptides with biological activity such as antihypertensive, antidiabetic, antioxidant, immunomodulatory, and mineral‐binding properties. However, the presence of biopeptides in cheese does not imply actual biological activity in vivo because these peptides can be further hydrolyzed during gastrointestinal transit. This paper reviews the recent advances in biopeptide formation in ripened cheeses production, focusing on the influence of technological parameters affecting proteolysis and the consequent release of peptides. The main discoveries in the field of cheese peptide digestion through recent in vivo and in vitro model studies are also reviewed. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Raw ewe's milk, as used to manufacture Serra da Estrela Protected Designation of Origin cheese, was pre‐treated by high pressure processing (HPP), using previously optimized conditions (121 MPa for 30 min), aiming to evaluate its effect on milk technological properties for subsequent cheese production, namely the impact on resulting curd, whey and cheese throughout ripening. RESULTS: The cheese yield increased 10.4% as a result of milk pre‐treated by HPP, which also yielded inactivation of beneficial microbial groups. After 60 days of ripening, both treated and control cheeses showed no significant differences (P ≥ 0.05) with respect to quantified microbial load or basic physicochemical quality parameters. CONCLUSION: HPP appears to be a promising non‐thermal treatment for ewes' milk to inactivate contaminant bacteria but with no negative effect on lactic acid bacteria, which is very important for the unique characteristics of Serra da Estrela cheese. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The International Journal of Dairy Technology has announced the appointment of two new Editorial Board members: Prof Ammar Mohammed Hamood Al‐Farga from the University of Jeddah, Saudi Arabia, and Dr Norah O'Shea from Teagasc Food Research Centre, Ireland. The journal will also be publishing a Special Issue on the digitalization of processing in the dairy industry, based on articles presented at the SDT 80th Anniversary Conference. In addition, the journal will introduce new article submission categories in 2024, including invited reviews, mini‐reviews, invited mini‐reviews, and case studies. The Editor's Choice Article for the February 2024 issue is titled "Consumption of mite‐ripened cheese did not impair the physiological status of both the non‐immunosuppressed and immunosuppressed mice." The study, conducted by Michelle Carvalho and colleagues from Brazil, evaluated the effects of feeding cheeses ripened with Tyrophagus putrescentiae mites on the physiological status of mice. While the study found that consuming cheese ripened with these mites is potentially safe, it could not rule out the possibility of mite-induced allergenic reactions in sensitive individuals. [Extracted from the article]

The fatty acid (FA) composition of milk from six European areas, as well as the alteration in the FA profile during cheese production, was studied using both a targeted GC‐FID and an untargeted GC‐MS approach. By applying principal component, partial least square discriminant and chemical similarity enrichment analysis, a discrimination of the geographical areas could be achieved highlighting important FA classes such as odd‐ and branched‐chain FAs for the differentiation. The FA profile remained constant during cheese production, and aroma compounds have been identified as biomarkers for the ripening methods used, namely foil and smear ripening. [ABSTRACT FROM AUTHOR]

This study aimed to compare the three strains of Listeria monocytogenes survival in raw milk cheese and pasteurized milk cheese and to suggest the effect of milk microbiota on survival. L. monocytogenes cell counts decreased in all cheese as ripening time increased, and the survival rate was different for the strains of L. monocytogenes. Furthermore, L. monocytogenes survived longer in raw milk cheese than in pasteurized milk cheese. The difference of bacterial survival in each cheese was independent of Aw or the Lactobacillus spp. populations in cheeses; there was no difference in Aw or Lactobacillus spp. populations in all cheeses. The richness of microbiota in raw milk was little higher than in pasteurized milk, and five phyla (Chloroflexi, Cyanobacteria, Deinococcus–Thermus, Lentisphaerae, and Verrucomicrobia) were present only in raw milk. Also, organic acid‐producing bacteria were presented more in pasteurized milk compared with raw milk; thus, the growth of L. monocytogenes was slower in pasteurized milk. In conclusion, differences in the microbial community of milk can affect the growth of L. monocytogenes. Making cheese using raw milk is a risk of L. monocytogenes infection; thus, efforts to prevent growth of L. monocytogenes such as the use of appropriate food additives are required. [ABSTRACT FROM AUTHOR]

Summary: The aim of this study was to determine the survival kinetics of Salmonella enterica subsp. enterica in ripened raw milk cheese. Cheese samples inoculated with S. enterica subsp. enterica were stored at 5, 15 and 25 °C and analysed in terms of physico‐chemical and microbiological characteristics. Three primary models were used to estimate the kinetic parameters of S. enterica subsp. enterica. The secondary Arrhenius model was used to establish the relationship between temperature and parameter α of the Weibull model. Additionally, prediction of S. enterica subsp. enterica survival as a function of storage temperature was made. S. enterica subsp. enterica growth was inhibited during storage, and bacteria survived for an extensive period of time at high number (60 day at 5 °C, 26 day at 25 °C). The storage temperature significantly influenced the inactivation rate of Salmonella in raw milk ripened cheese and proceeded faster at 25 °C compared to remaining storage temperature. Obtained results suggest that contamination by Salmonella in raw milk cheese might result in residual risk. [ABSTRACT FROM AUTHOR]

A time‐domain 1H nuclear magnetic resonance relaxometry method was elaborated for the rapid microstructural characterization of mozzarella cheese. For this purpose, there is a strong need to know how the experimentally determined T2 relaxation time distribution can be related to specific constituents in mozzarella. In this study, a detailed investigation is offered for fresh and aged low‐moisture mozzarella cheese, often applied as a pizza cheese, by application of both a conventional Carr–Purcell–Meiboom–Gill (CPMG) sequence and a free‐induction decay CPMG (FID‐CPMG) sequence. The relaxation behavior was further elucidated by addition of deuterium oxide and by mild heat treatment of samples. The relaxation times of water protons in mozzarella were found to range from a few microseconds to some tens of milliseconds (in aged mozzarella) or to about hundred milliseconds (in fresh mozzarella). The upper limit of the T2 distribution can even be extended to the seconds range upon releasing water protons from the mozzarella matrix using a mild heat treatment or upon addition of deuterated water. Both stimuli also provided evidence for the absorption of water into the cheese matrix. The potential release and uptake of water demonstrated that mozzarella acts as a very dynamic system during production and storage. The detected differences in the behavior of the water fraction between fresh and aged low‐moisture mozzarella might be utilized to study the influence of either production and/or storage conditions on the cheese ripening process. [ABSTRACT FROM AUTHOR]

A large variety of cheeses exist in Brazil, reflecting historical and cultural aspects. Brazilian artisanal cheeses present differences in the processing, ripening time (when applied), type of milk used, texture, size, shape, color, moisture content, flavor, the use or not of starter cultures, among others. This review describes the main artisanal cheeses produced in Brazil, focusing on general and particular characteristics associated with their making process and geographical identity. Overall, the high variability of the physicochemical data and deficiency of information on sensorial properties of Brazilian artisanal cheeses were noticed. On the other hand, culture‐dependent methods were mostly used to expand the knowledge into the microbiology of these cheeses, whereas their microbial diversity has been recently discovered through the use of 16S rRNA gene sequencing‐based methods. The certification of a geographical indication for Brazilian artisanal cheeses may encompass an essential milestone for adding value to these products. Regardless of their significance in the diet, culture, and economy of producing regions, taken together, the reviewed literature discloses the need of insightful studies to generate scientific data to support the expansion of the market, while ensuring the protection of historic aspects related to the production of Brazilian artisanal cheeses. [ABSTRACT FROM AUTHOR]

BACKGROUND: Cheese ripening involves a complex series of metabolic reactions and numerous concomitant secondary transformations. Alcohol dehydrogenase (ADH) converts aldehydes into their corresponding alcohols, which enrich cheese aroma. RESULTS: In this study, we identified five ADH genes in Proteus mirabilis JN458, and these genes were overexpressed and characterized in Escherichia coli BL21 (DE3). The optimum pH was 7.0 for the purified recombinant ADH‐1, ADH‐2, and ADH‐3 and 8.0 for ADH‐4 and ADH‐5. The optimum temperature was 40 °C for ADH‐1, ADH‐3, and ADH‐5 and 45 °C for ADH‐2 and ADH‐4. The Km value of ADH‐1, ADH‐2, and ADH‐3 was 34.45, 16.90, and 10.01 µmol L−1 for phenylacetaldehyde, respectively. The Km value of ADH‐4 and ADH‐5 was 14.81 and 24.62 µmol L−1 for 2‐methylbutanal, respectively. CONCLUSION: Proteus species play important roles during cheese ripening. The results of our study are important for further research on cheese flavor and for quality control during cheese production. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Summary: Cheese ripening is an important step in cheese making for modifying surface and curd properties. Due to physical, chemical and biological changes, mass loss usually occurs during the process. Although these changes are essential for developing the texture and flavour of cheese, mass loss decreases product yields. A reliable mathematical model is used to quantify mass loss during cheese ripening so that the processing conditions can be fine‐tuned to achieve the desirable throughput. In this study, for the first time, the reaction engineering approach (REA)‐based model is applied to model the cheese ripening. The study shows that the REA‐based model is accurate to model cheese ripening of Camembert and French smear cheese. In addition, the REA is able to model the cheese ripening under time‐varying environmental conditions. For this purpose, the equilibrium activation energy is evaluated according to the corresponding humidity and temperature in each period, while the same relative activation energy for ripening under constant environmental conditions is implemented. The REA is a simple yet effective approach to model the simultaneous heat and mass transfer process accompanied by chemical and biological reactions. Considering its effectiveness, the REA can be applied in industrial settings for predicting mass loss during cheese ripening. [ABSTRACT FROM AUTHOR]

The effect of ripening time on the microstructural, physicochemical and rheological characteristics of traditional Kope cheese ripened in clay pots was investigated. The moisture content, pH and total nitrogen (TN)/dry matter (DM) of the cheese decreased, and DM, fat in DM and water‐soluble nitrogen/TN increased during this period. Storage and loss moduli increased, while loss tangent decreased; as a result, the elasticity characteristics were greater than the viscous characteristics of the samples. Microstructure images showed that the size of pores and casein network density increased significantly during ripening and, after 90 days, the structure of many pores became very similar to each other. [ABSTRACT FROM AUTHOR]

Lactococcal and enterococcal adjuncts with verified anticlostridial activity were successfully applied in the technology process of Dutch‐type low‐scalded cheese. The microbial status of experimental cheeses, physicochemical parameters and late blowing defects were evaluated for batches inoculated with Clostridium tyrobutyricum, and compared with noninoculated controls and the application of nisin. Two strains (CCDM 731 and CCDM 71) belonging to the species Lactococcus lactis subsp. lactis had significant anticlostridial effects which were comparable to nisin. Regardless of the noneffective enterococci adjunct, both lactococcal strains effectively supported the fermentation and ripening process in combination with the commercial starter itself or in combination with nisin. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the proteolysis and lipolysis profiles of a raw ewes' milk cheese during production and ripening. The microbial community of this cheese was quantified, and their roles during proteolysis and lipolysis were studied. We observed an accumulation of substantial amounts of peptides during ripening, which might be attributed to the abundant presence of lactic acid bacteria, as well as to secondary microbiota including fungi, yeasts and actinobacteria. Similarly, high lipolysis levels were obtained, which can be explained by the indigenous lipase in milk and microbial lipases. These results should be of great interest to industrial manufacturers of this cheese. [ABSTRACT FROM AUTHOR]

The study aimed to assess the impact of ripening at elevated temperatures on the survival of probiotic micro-organisms and production of organic acids in Cheddar cheese. Cheese was manufactured from buffalo milk using lactococci starters along with different probiotic bacteria ( Lactobacillus acidophilus LA-5, Bifidobacterium bifidum Bb-11 and Bifidobacterium longum BB536) as adjunct cultures. The cheeses were ripened at 4-6 °C or 12-14 °C for 180 days and examined for composition, organic acids and microbial survival. The production of organic acids was accelerated at 12-14 °C when compared to normal ripening temperatures. The probiotic bacteria increased production of lactic and acetic acids, compared to cheese made with lactococci alone. The survival of the mesophilic starters was significantly ( P < 0.05) reduced in all the cheese samples ripened at the higher temperature. However, the probiotic bacteria remained viable (>7.0 log10 cfu/g) throughout the 180 days of ripening, irrespective of temperature. It was concluded that Cheddar containing additional probiotic cultures can effectively be ripened at elevated temperatures without any adverse effects. [ABSTRACT FROM AUTHOR]

Pico cheese is a traditional variety manufactured on the eponymous Azorean Island (Portugal). In total, 153 cheeses were analysed. The average total solids (TS) content by the end of maturation was 63.3 ± 0.3 g/100 g, Aw 0.943-0.966, salt-in-moisture 2.12-4.17 g/100 g and pH 4.89-5.11 ± 0.02. Proteolysis was similar to that of other Iberian raw milk cheeses, but the free fatty acid content was generally higher. Lactococci were the predominant bacteria. Coagulase-positive staphylococci constituted the most severe hygiene problem. Positive correlations were found between maturation time and TS, titratable acidity, Aw, proteolysis indices and Enterobacteriaceae and coagulase-positive staphylococcus viable numbers. [ABSTRACT FROM AUTHOR]

The efficacy of donkey milk as an alternative to hen's egg white lysozyme in preventing cheese blowing during ripening of Italian Grana cheeses was tested. Indices of proteolysis and lipolysis did not differ between the different cheesemaking processes. All tested products showed good microbiological and sensorial quality. [ABSTRACT FROM AUTHOR]

This study investigated the behaviour and fate of Listeria monocytogenes at different ripening temperatures and NaCl concentrations in traditional Lighvan cheese. L. monocytogenes was added to raw sheep's milk. After producing the cheese, they were stored in 8%, 12% and 15% NaCl at 4, 9 and 14 °C. Sampling was performed for 150 days. Different temperature and NaCl concentrations had a significant effect on the survival of L. monocytogenes ( P < 0.001). The lowest growth and survival rates of L. monocytogenes were in 15% NaCl at 14 °C and 12% NaCl at 14 °C, respectively. Also, the highest growth and survival rates of the bacterium were in 8% NaCl at 4 °C. [ABSTRACT FROM AUTHOR]

The cheesemaking suitability of the milk of native cow breeds [Polish Red ( RP) and White-Backed ( BG)] raised on low-input farms was assessed. The milk of Polish Holstein-Friesian cows raised in an intensive system constituted the reference group. Chemical composition, pH, rennet coagulation time, fat dispersion and curd texture were determined. The cows on the low-input farms produced over 40% less milk, but with higher ( P ≤ 0.01) fat content, shorter coagulation time by over 2 min and lower ( P ≤ 0.05) fat dispersion. The curds from this milk were significantly springier, more cohesive and harder. The best milk indices were obtained for the RP cows. [ABSTRACT FROM AUTHOR]

BACKGROUND White mold-ripened cheeses were investigated with the objective of proposing a colorimetric method to monitor the surface growth of Penicillium candidum and to evaluate the influence of the mesophilic (homofermentative ( QMO) and heterofermentative ( QMLD)) and thermophilic ( QT) starter cultures on the physicochemical composition and sensory description. RESULTS The whiteness index was effective in proving the appearance of superficial mycelium and the stability of white mold growth. The lactic cultures showed significant influence on most of the physicochemical analyses. The cheese made with thermophilic lactic culture had a 1 day gain in the growth of mycelium on the surface; nevertheless, the appearance of this product was potentially not acceptable for consumers. The heterofermentative mesophilic cheese had a better appearance and texture profile. However, the homofermentative mesophilic cheese showed aspects of fresh cheese and was acceptable for a wide range of consumers. CONCLUSION The whiteness index was efficient to monitor the surface growth of P. candidum. The highest proteolytic effect was found in the QMLD and QT cultures. However, the cheese elaborated with the QMLD culture showed the best sensory acceptance. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The effect of 0.02% gum tragacanth, sodium caseinate or milk protein concentrate ( MPC70) on the physiochemical, microstructural and textural properties of Lighvan cheese produced from bovine milk was investigated. The microstructure of cheese samples was studied by scanning electron microscopy ( SEM), and the SEM micrographs were analysed using 3 D images, surface plots and binarised SEM images. The texture parameters of bovine Lighvan cheese containing sodium caseinate were similar to those of ovine Lighvan cheese, and the microstructure of the MPC-containing bovine Lighvan cheese was closest to that of ovine Lighvan cheese. [ABSTRACT FROM AUTHOR]

This study deals with proteolysis and total antioxidant capacity of proteins of white brined cheese prepared from overheated goat milk and ripened for fifty days. Proteolytic changes were reflected through the relatively low level of soluble nitrogen (50 days ripened cheese had 15.32 g/100 g of water-soluble nitrogen, 8.1 g/100 g of TCA-soluble nitrogen and 2.69 g/100 g of PTA-SN), intensive proteolysis of αs2-CN during initial 10 days of ripening (up to 50.70% of initial content) and its much slower degradation through further 40 days, slow but continual decrease of β-CN content (up to 85.14% of residual content) and high level of proteolytic products tightly bounded into gel network. Total antioxidant capacity of water-soluble and water-insoluble fractions increased after cheese ripening. These findings could be useful for better understanding and control over the production of white brined goat cheese as highly valuable functional product. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ripened cheese is among fermented food the most often associated with food poisoning from biogenic amines. The influence of ripening time, heat treatment of milk and the effect of using milk from a different ewe breed on the biogenic amine (BA) content of Zamorano cheese was studied by high-performance liquid chromatography. Physicochemical, proteolytic andmicrobiological parameters were also studied. RESULTS: BA content increased significantly during ripening and their final values were around 400mg kg-1. Cheeses elaborated with raw milk duplicated the concentration of BA relative to those elaborated with pasteurized milk (72 °C for 20 s). The average levels of putrescine, spermine and tyramine were higher in cheeses made with a greater proportion of milk from Churra breed. Significant differences in microbial counts and nitrogen soluble in 5% phosphotungstic acid were observed between the different batches. CONCLUSION: Ripening time and heat treatment applied to milk were the factors that exercised the greatest influence upon the concentration of BA in Zamorano cheese. [ABSTRACT FROM AUTHOR]

Saffron spice has been successfully used as an ingredient in dairy products as a means of diversification. The objective of this work was to determine the influence of saffron on the volatiles' profile of a pressed ewes' milk cheese. This was performed by means of a modern extraction technique based on headspace sorptive extraction. Results showed that safranal was the only volatile that could be identified and quantified from saffron spice. Most volatile compounds were present in all cheeses but at different concentrations. Differences between control and saffron cheeses were observed, but as ripening time increased, these differences were less evident. [ABSTRACT FROM AUTHOR]

São João cheeses with varying curd dry salting treatments were made with decreasing levels of salt (sodium chloride): 4 (control), 3, 2 and 1% (w/w), along with the salt-free version. The cheeses were ripened at 11 ° C over a 40-day period, and the effect of lowering salt on the physicochemical, microbiological and sensory properties of the cheese was studied. Reduced salt resulted in a concomitant moisture decrease with protein increase, ash and sodium reduction among experimental cheeses at the same ripening day, but there were no significant differences in p H, acidity and fat, or in the microbiological quality. Triangle tests indicated perceptible differences between test and control cheeses at the level of 2% Na Cl (w/w) or less, but not with the cheese salted with 3 g Na Cl/100 g. Considering the sensory, the physicochemical and the microbiological results, the cheese formulated at 3% Na Cl (w/w) (presenting a reduction of 25% in salt) is feasible on an industrial scale, being indistinguishable by the regular consumer. [ABSTRACT FROM AUTHOR]

The aim of this study was to characterise industrial Tetilla and Cebreiro Protected Designation of Origin (PDO) Spanish cheeses from a biochemical point of view and to relate some of the biochemical parameters to the cheesemaking process. Some differences in the amounts of organic acids and free amino acids between the two types of cheese were attributed to milk characteristics and the processing technology. The most abundant volatile compounds in both types of cheese were ethanol, isopropanol and diacetyl. The simple and nonspecific volatile profiles of the cheeses appear to be related to the commercial mesophilic DL-starters used in the manufacturing process. [ABSTRACT FROM AUTHOR]

BACKGROUND Physicochemical characteristics, proteolysis and lipolysis were studied throughout the ripening of eight batches of a traditional Spanish variety made from raw cow's milk, in order to establish a basis for its industrial production. RESULTS The main compositional characteristics of this cheese after 60 days of ripening were its high proportion of total solids ( TS; 752 g kg−1 of cheese), an average content of protein (452.8 g kg−1 TS) and fat (475.1 g kg−1 TS) and the presence of residual lactose (12.5 g kg−1 TS). Its pH value (4.04) was extremely low. Phosphorus (5.13 g kg−1 TS) and sodium (8.29 g kg−1 TS) were the most abundant mineral elements in cheese, whereas calcium levels (1.92 g kg−1 TS) were very low. Proteolysis extension and depth were very low, which resulted in almost zero degradation of αs1- and β-casein. Fat acidity increased during ripening, reaching final values of 50.1 mg KOH kg−1 of fat. The main free fatty acid was C16:0, followed by C18:1 and C14:0. CONCLUSION These results suggest that this variety undergoes a limited proteolysis and moderate lipolysis during ripening. The low pH, low calcium content and limited proteolysis led to a crumbly texture in this cheese variety. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Among microencapsulation techniques used in food production, nanoliposomes are known to be one of the most interesting methods for the encapsulation of flavours, essential oils, amino acids, vitamins, minerals, enzymes, micro-organisms, redox agents, colourants, antioxidants and antimicrobials. Research has also been conducted on possible applications of nanoliposomes in cheese production by the encapsulation of ferrous glycinate, ferrous sulphate, antioxidants, nisin, β-galactosidase and cheese-ripening enzymes. In this article, nanoliposome application in cheese production has been reviewed under three main themes, namely (i) acceleration of cheese ripening, (ii) fortification of cheese with vitamins and minerals and (iii) increasing shelf life of cheese products. Various aspects of nanoliposome application in cheese technology including currently available preparation methods, efficiency of nanoliposomal enzymes, their effects on the acceleration of cheese ripening as well as rheological and chemical properties of the cheese curd are discussed. [ABSTRACT FROM AUTHOR]

UF-Feta cheese was analyzed among three plants for total microorganisms, aerobic spores and B acillus cereus in three parts (core, rind and brine) during ripening and shelf life. Then, hemolysin BL, cereolysin A and cereolysin B genes as virulence factors were investigated in the B . cereus isolates. The results show that in spite of significant decrease of the total count, the variation of B . cereus spores and aerobic spores was not meaningful during shelf life. It may be due to the sporelation of B . cereus in severe condition of UF-Feta cheese. The results also show that B . cereus is well adapted to Feta cheese condition with low pH, and can present up to the end of shelf life. Moreover, in the detection of toxin-producing genes, 30% of isolates were found to carry three genes. In conclusion, B . cereus isolated from UF-Feta cheese should be considered as potential enterotoxin producers. Therefore, new efforts should be undertaken to restrict these organisms during manufacturing for food safety. Practical Applications B acillus cereus is a foodborne pathogen found in dairy products. However, some studies were reported that this microorganism cannot survive at low pH like UF-Feta cheese. The results of the present study indicate that B . cereus can tolerate the acidity and storage temperature. In addition, occurrences of toxin-producing genes which include diarrheal toxins provide useful information in risk assessment of food poisoning caused by B . cereus. Thus, the presence of it in UF-Feta cheese may be potential risk factors for consumer health and should be considered a serious public health hazard. [ABSTRACT FROM AUTHOR]

Raw milk and its products play a considerable role in spreading B rucella infection. The purpose of this study was to determine the growth and survival abilities of B rucella abortus (NCTC - National Collection of Type Cultures 10863) and B rucella melitensis ( NCTC 10094) during the production and the ripening of Afyon Tulum cheese. B . abortus was inhibited in group inoculated at 4 log cfu/g, at the 15th day of ripening. In the group inoculated at 6 log cfu/g, B . abortus was inhibited at the 45th day of ripening. B . melitensis was inhibited in groups inoculated at 4 and 6 log cfu/g, at the 30th day of ripening. The growth and survival of B . abortus and B . melitensis were influenced by the type of strains and numbers inoculated in the Afyon Tulum cheese samples. It is important to produce Afyon Tulum cheese from B rucella spp.-free milk and to mature Afyon Tulum cheese for the correct minimum time period. Practical Applications B rucella spp. are zoonotic infections for humans. Raw milk and especially cheese are potential sources for the transmission of B rucella spp. Afyon Tulum cheese must be produced from pathogen-free raw milk for public health and characteristic properties. [ABSTRACT FROM AUTHOR]

Kashar cheeses were manufactured from pure ovine ( OV), bovine ( BV) and caprine ( CP) milk, and the chemical composition, cheese yield, proteolysis, hardness, meltability and volatile composition were studied during 90 days. Gross chemical composition, cheese yield and level of proteolysis were higher in OV cheeses than those of BV or CP cheeses. Glu, Val, Leu, Phe and Lys were the most abundant free amino acids ( FAA) in the samples, and the concentrations of individual FAA were at the highest levels in OV cheeses with following BV and CP cheeses. Urea- PAGE patterns and RP- HPLC peptide profiles of the BV cheeses were completely different from the small ruminants' milk cheeses ( OV or CP). Higher and lower hardness and meltability values were observed in CP cheeses, respectively. OV cheeses resulted in higher levels of the major volatile compounds. In conclusion, the Kashar cheese made using OV milk can be recommended due to high meltability, proteolysis and volatiles. [ABSTRACT FROM AUTHOR]

A new device named a cell sonicated substrate membrane system ( CSSMS), consisting of a tissue culture insert that supplies nutrients, in the form of starter lactic acid bacteria ( SLAB) lysate extract, through a polycarbonate membrane which isolates it from the nonstarter lactic acid bacteria ( NSLAB) inoculum and serves as a support for bacterial growth, was developed. The CSSMS was used to demonstrate that the Lactobacillus helveticus SLAB lysate provides sufficient nutrients to allow the growth of L. casei and L. rhamnosus NSLAB in vitro. The results support the hypothesis that NSLAB could grow in aged cheese using only SLAB cell lysate as nutrients. [ABSTRACT FROM AUTHOR]

Important fungi growing on cheese include Penicillium, Aspergillus, Cladosporium, Geotrichum, Mucor, and Trichoderma. For some cheeses, such as Camembert, Roquefort, molds are intentionally added. However, some contaminating or technological fungal species have the potential to produce undesirable metabolites such as mycotoxins. The most hazardous mycotoxins found in cheese, ochratoxin A and aflatoxin M1, are produced by unwanted fungal species either via direct cheese contamination or indirect milk contamination (animal feed contamination), respectively. To date, no human food poisoning cases have been associated with contaminated cheese consumption. However, although some studies state that cheese is an unfavorable matrix for mycotoxin production; these metabolites are actually detected in cheeses at various concentrations. In this context, questions can be raised concerning mycotoxin production in cheese, the biotic and abiotic factors influence their production, mycotoxin relative toxicity as well as the methods used for detection and quantification. This review emphasizes future challenges that need to be addressed by the scientific community, fungal culture manufacturers, and artisanal and industrial cheese producers. [ABSTRACT FROM AUTHOR]

Croatian traditional cheese, which ripens in a lamb skin sack, was studied to determine compositional, biochemical and sensory changes over 60 days of ripening. The ripening time had a significant effect on the chemical, biochemical and sensory parameters, particularly on the medium- and long-chain free fatty acids ( P < 0.05) and total FFAs ( P < 0.001). At the end of ripening palmitic, oleic and stearic acids were the predominant FFAs. Cheese ripened for more than 45 days was less acceptable to consumers as a consequence of extensive proteolysis and lipolysis. Therefore, ripening for more than 45 days, which is commonly practised by cheesemakers, is not recommended. [ABSTRACT FROM AUTHOR]

Milk contains a complex mixture of proteins that undergo several qualitative and quantitative changes during processing and storage. Elucidation of these changes is important to optimise milk processing and storage parameters. Proteomics has become widely used in the field of research on milk proteins due to improvements in the tools and diversified ways in which the methodologies of protein analysis have been developed. This review describes the use of proteomics in studies on milk proteins in relation to species-species differences, post-translational modification, effect of lactation, mastitis, changes in heated milk and during cheese ripening, and the detection of milk adulteration. [ABSTRACT FROM AUTHOR]

Kurdish cheese has been traditionally prepared from raw milk in the northeast of Iran. It is ripened in goat's skin bags. This study was conducted on microbiological diversity and physicochemical properties of Kurdish cheese during ripening (1, 20, 40 and 60 days). The results indicated that the type and counts of microorganisms were mainly influenced by ripening time. Lactic acid bacteria and Enterobacteriaceae were predominant during the first 20 days of ripening, and lactobacilli were the most common microorganisms found during ripening. The initial numbers of coliforms and E . coli decreased rapidly, whereas a gradual increase in counts of moulds and yeasts was noticed in the early days of ripening. Coliforms, S almonella and coagulase-positive S taphylococcus spp. were undetectable in ripened cheese. The optimal time for consuming is after 60 days because the undesired biota decreased below dangerous limits. pH, moisture content and aw decreased during ripening. No significant variations were observed in protein values during ripening. The textural parameters such as hardness, chewiness and gumminess increased as ripening progressed, but springiness decreased. The level of microelements in cheese samples during maturation were in the following order Na > Ca > K > Zn > Cu. Practical Applications Kurdish cheeses have been traditionally prepared, and the market for them has existed in many parts of Iran for many years. Its microbial diversity originates from natural microbiota present in the raw milk, and environmental exposures are important points to consider for public health. There is an increased demand from consumers for high-quality natural food, free from contaminating microorganisms. Hence, indigenous lactic acid bacteria were identified successfully for production of fermented milk products with increased safety. Given the significant economic importance of Kurdish cheeses to a number of small domestic and industrial producers, particularly in the northeast of Iran, this study can be used to help implement strategies designed to enhance the product's microbiological and physicochemical quality. [ABSTRACT FROM AUTHOR]

The objective of the study was to determine the effects of exopolysaccharide ( EPS)-producing or non- EPS-producing starters on proteolysis, physical and microstructural characteristics of full-fat or low-fat Tulum cheeses during ripening. For this purpose, Tulum cheese was manufactured using full- or low-fat milk with EPS-producing and non- EPS-producing starter cultures. Chemical composition, proteolysis, texture profiles and microstructure of the cheeses were studied during 90 days of ripening. Urea- PAGE of water-insoluble and RP-HPLC peptide profiles of water-soluble fractions of the cheeses showed that the use of starters resulted in different degradation patterns in all cheeses during ripening. Although β-casein exhibited similar degradation patterns in all cheeses, small differences are present in αs1-casein degradation during ripening. Reducing fat in Tulum cheese changed the RP- HPLC peptide profile of the cheeses. The use of EPS-producing cultures improved the textural characteristics and changed the microstructure and proteolysis of low-fat Tulum cheese. [ABSTRACT FROM AUTHOR]

The effect of (+)-catechin on total phenolic content (TPC) and antioxidant properties in low-fat hard cheese were examined over a 90-day ripening period at 8 °C. Antioxidant activity ( AA) in cheese was measured by ferric reducing antioxidant power, oxygen radical absorbance capacity ( ORAC) and 2,2-diphenyl-1-picrylhydrazyl assays and compared with TPC. Catechin retention coefficients in cheese curds were in the range of 0.63-0.75 and decreased the pH of cheese without affecting protein, fat or moisture content. Both TPC and AA increased during the 90-day ripening period. Oxygen radical absorbance capacity was the most suitable technique for evaluating AA in cheese due to the high correlation with TPC and suitability in both lipophilic and hydrophilic systems. [ABSTRACT FROM AUTHOR]

The effect of Lactococcus lactis nisin-producing strains, isolated from Italian fermented foods, on the survival of two foodborne pathogens namely Listeria monocytogenes and Staphylococcus aureus was investigated in experimental cheese production. One of the three Lactobacillus lactis nisin innoculated as starters, Lactobacillus lactis 41 FL1 lowered S. aureus count by 1.73 log colony-forming units (cfu)/g within the first 3 days, reaching the highest reduction, 3.54 log cfu/g, by the end of ripening period of 60 days. There was no effect on L. monocytogenes. The application of L. lactis 41 FL1 as bioprotective culture in controlling S. aureus shows considerable promise. [ABSTRACT FROM AUTHOR]