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The impacts of salt reduction by NaCl sprinkling and NaCl substitution with 25% calcium lactate on the quality of blue cheese were evaluated. Sprinkling reduced sodium content by 35% and substitution reduced sodium content by 47%. The salt‐reduced cheeses had a higher calcium content, vitamin B2, B6, and B12 levels, and a higher rate of proteolysis. Sensory and texture profile analysis found that the salt‐reduced cheeses had a less salty taste and were less firm. These methods enabled significant salt reduction but had negative effects on the cheese properties, and so further work is needed to diminish these effects. [ABSTRACT FROM AUTHOR]

Penicillium roqueforti is a fungal starter culture used for the production of blue-veined cheeses, such as Roquefort, Gorgonzola, Stilton, Cabrales, and Danablue. During ripening, this species grows in the veins of the cheese, forming the emblematic blue-green color and establishing the characteristic flavor owin to its biochemical activities. P. roqueforti synthesizes a diverse array of secondary metabolites, including the well-known compounds roquefortine C, clavine alkaloids, such as isofumigaclavine A and B, mycophenolic acid, andrastin A, and PR-toxin. This review provides an in-depth exploration of P. roqueforti's secondary metabolites, focusing on their biosynthetic pathways, the gene clusters responsible for their production, and their bioactivities. The presence of these compounds in blue cheeses is also reviewed. Furthermore, the silent clusters and the potential of P. roqueforti for producing secondary metabolites were discussed. The review highlights recently identified metabolites, including sesterterpenoids; tetrapeptides, D-Phe-L-Val-D-Val-L-Tyr, and D-Phe-L-Val-D-Val-L-Phe; cis-bis(methylthio)silvatin; and the 1,8-dihydroxynaphthalene (DHN)-melanin precursor, scytalone. Additionally, a gene cluster for DHN–melanin biosynthesis is presented. Finally, a revised cluster for roquefortine C biosynthesis comprising three rather than four genes is proposed. [ABSTRACT FROM AUTHOR]

Polyamine intake has been reported to help extend the lifespan of animals. Fermented foods contain high concentrations of polyamines, produced by fermenting bacteria. Therefore, the bacteria, isolated from fermented foods that produce large amounts of polyamines, are potentially used as a source of polyamines for humans. In this study, the strain Levilactobacillus brevis FB215, which has the ability to accumulate approximately 200 µM of putrescine in the culture supernatant, was isolated from fermented foods, specifically the Blue Stilton cheese. Furthermore, L. brevis FB215 synthesized putrescine from agmatine and ornithine, which are known polyamine precursors. When cultured in the extract of Sakekasu, a byproduct obtained during the brewing of Japanese rice wine containing high levels of both agmatine and ornithine, L. brevis FB215 grew to OD600 = 1.7 after 83 h of cultivation and accumulated high concentrations (~1 mM) of putrescine in the culture supernatant. The fermentation product also did not contain histamine or tyramine. The Sakekasu-derived ingredient fermented by the food-derived lactic acid bacteria developed in this study could contribute to increasing polyamine intake in humans. [ABSTRACT FROM AUTHOR]

Filamentous fungi are an important source of natural products. The mold Penicillium roqueforti, which is well-known for being responsible for the characteristic texture, blue-green spots, and aroma of the so-called blue-veined cheeses (French Bleu, Roquefort, Gorgonzola, Stilton, Cabrales, and Valdeón, among others), is able to synthesize different secondary metabolites, including andrastins and mycophenolic acid, as well as several mycotoxins, such as Roquefortines C and D, PR-toxin and eremofortins, Isofumigaclavines A and B, festuclavine, and Annullatins D and F. This review provides a detailed description of the biosynthetic gene clusters and pathways of the main secondary metabolites produced by P. roqueforti, as well as an overview of the regulatory mechanisms controlling secondary metabolism in this filamentous fungus. [ABSTRACT FROM AUTHOR]

Penicillium roqueforti is a fungal starter culture used for the production of blue-veined cheeses, such as Roquefort, Gorgonzola, Stilton, Cabrales, and Danablue. During ripening, this species grows in the veins of the cheese, forming the emblematic blue-green color and establishing the characteristic flavor owin to its biochemical activities. P. roqueforti synthesizes a diverse array of secondary metabolites, including the well-known compounds roquefortine C, clavine alkaloids, such as isofumigaclavine A and B, mycophenolic acid, andrastin A, and PR-toxin. This review provides an in-depth exploration of P. roqueforti’s secondary metabolites, focusing on their biosynthetic pathways, the gene clusters responsible for their production, and their bioactivities. The presence of these compounds in blue cheeses is also reviewed. Furthermore, the silent clusters and the potential of P. roqueforti for producing secondary metabolites were discussed. The review highlights recently identified metabolites, including sesterterpenoids; tetrapeptides, D-Phe-L-Val-D-Val-L-Tyr, and D-Phe-L-Val-D-Val-L-Phe; cis-bis(methylthio)silvatin; and the 1,8-dihydroxynaphthalene (DHN)-melanin precursor, scytalone. Additionally, a gene cluster for DHN–melanin biosynthesis is presented. Finally, a revised cluster for roquefortine C biosynthesis comprising three rather than four genes is proposed.

A heleomyzid fly Tephrochlamys rufiventris (Meigen, 1830), was reared from a form of blue cheese aging in a refrigerated, dark, aging room of a small northern California creamery. The third-instar larva is redescribed and the puparium is described for the first time.

Yeasts constitute an important part of cheeses, and especially the artisanal ones. The current study reviews the occurrence of yeasts in different cheese varieties and the role of yeasts in cheesemaking process. The use of molecular methods for identification and strain typing has extended the knowledge for yeast diversity in cheeses. For the study of the occurrence of yeasts in different cheese types, seven categories are used, that is: 1) hard, 2) semi-hard, 3) soft, which includes soft pasta-filata and whey cheeses, 4) white brined cheeses, 5) mould surface ripened, 6) bacterial surface ripened cheeses, and 7) blue cheeses. For some cheese types, yeasts are the main microbial group, at least for some part of their ripening process, while for some other types, yeasts are absent. Differences between industrially manufactured cheeses and artisanal cheeses have specified. Artisanal cheeses possess a diverse assortment of yeast species, mainly belonging to the genera Candida, Clavisporalus, Cryptococcus, Debaryomyces, Geotrichum, Issatchenkia, Kazachstania, Kluyveromyces, Kodemaea, Pichia, Rhodotorula, Saccharomyces, Saturnispora, Torulaspora, Trichosporon, Yarrowia and ZygoSaccharomyces. The role of the yeasts for selected cheeses from the seven cheese categories is discussed.

Blue cheese flavour development derives from complex biochemical reactions that depend on numerous factors including milk source, culture/strain selection, processing, and ripening conditions. Understanding volatile compound development during blue cheese ripening will help reduce production costs and facilitate quality improvements. Volatile compounds contribute to the characteristic flavours of the cheeses but ripening time predictions based on chemical data have proven difficult. The present study employed untargeted fingerprinting combined with linear and non-linear chemometric approaches to identify key volatiles for the modelling of Shenley Station blue cheese ripening times. Self-organizing maps and entropy-based feature selection along with partial least squares regression and variable identification coefficients were used to parse the linear and non-linear development behaviours of volatiles. The blue cheese ripening times were accurately modelled by twenty-three discriminant volatiles. The present study demonstrated that volatile fingerprints can be used to effectively model blue cheese ripening times using a non-linear chemometric approach.

Polyamine intake has been reported to help extend the lifespan of animals. Fermented foods contain high concentrations of polyamines, produced by fermenting bacteria. Therefore, the bacteria, isolated from fermented foods that produce large amounts of polyamines, are potentially used as a source of polyamines for humans. In this study, the strain Levilactobacillus brevis FB215, which has the ability to accumulate approximately 200 µM of putrescine in the culture supernatant, was isolated from fermented foods, specifically the Blue Stilton cheese. Furthermore, L. brevis FB215 synthesized putrescine from agmatine and ornithine, which are known polyamine precursors. When cultured in the extract of Sakekasu, a byproduct obtained during the brewing of Japanese rice wine containing high levels of both agmatine and ornithine, L. brevis FB215 grew to OD600 = 1.7 after 83 h of cultivation and accumulated high concentrations (~1 mM) of putrescine in the culture supernatant. The fermentation product also did not contain histamine or tyramine. The Sakekasu-derived ingredient fermented by the food-derived lactic acid bacteria developed in this study could contribute to increasing polyamine intake in humans.

Filamentous fungi are an important source of natural products. The mold Penicillium roqueforti, which is well-known for being responsible for the characteristic texture, blue-green spots, and aroma of the so-called blue-veined cheeses (French Bleu, Roquefort, Gorgonzola, Stilton, Cabrales, and Valdeón, among others), is able to synthesize different secondary metabolites, including andrastins and mycophenolic acid, as well as several mycotoxins, such as Roquefortines C and D, PR-toxin and eremofortins, Isofumigaclavines A and B, festuclavine, and Annullatins D and F. This review provides a detailed description of the biosynthetic gene clusters and pathways of the main secondary metabolites produced by P. roqueforti, as well as an overview of the regulatory mechanisms controlling secondary metabolism in this filamentous fungus.

The presence of areas with growth mold and their distribution in cheese matter are significant factors for blue cheese quality. Traditionally these parameters are evaluated by sensory profiling using experts' knowledge. Thus the assessment is subjective and performance time variate depends on current providing of experts services. Previous researches proof that methods of computer vision could help for fast and accurate analysis of quantity of mold on the blue cheese cut surface. The methods of statistical analysis also could support mold analysis in blue cheese in order to be evaluated the evenness of their distribution. The main purpose of current research is to propose an approach for automatic mold analysis in blue cheese using CVS (Computer Vision System) and software tools included in NI LabVIEW environment in order to perform complex analysis of mold growth. The selected blue cheese trademarks were: Bergader, Dorblu with 50% fat, Dorblu with 55% fat, Paladin ReginaBlu, and Steffel Gran Bavarese. Every sample is cut on slices and these slices are evaluated by experts and captured with digital camera in CVS. An upgraded CVS is used for data acquisition and a specially developed application in NI LabVIEW environment processes cheese images and presents reports for quantity of mold and its distribution using different grid size. Assessment of blue cheese quality is performed by experts using Likert scale for two parameters- quantity of mold and evenness of their distribution. This scale assign points for naturally described scores about blue cheese quality. A correlation analysis is performed for assessments of blue cheese quality received through computer analysis and experts estimation in order to be evaluated effectiveness of proposed approach. The results show that experts' estimation about quantity of mold strongly corresponds with calculated value using developed application (Pearsons' coefficient is ≈ 0.96) and experts' estimation about evenness of mold distribution also corresponds with calculated values (Pearsons' coefficient is ≈ 0.99) using grid size 4 x 4 and thresholding methods Inter-class variance and Clustering. It is observed that when the quantity of mold is very small (mean value below 1%) and standard deviation about its value is also small (below 0.3), then the calculated factor of evenness has high value because more of ROIs have also very small quantity of mold. The samples with high quantity of mold (in the range from 3% to 4%) are presented with high standard deviation (in the range from 1.5 to 3.5) which could be explained with presence of areas (ROIs) with quantity of mold smaller than mean value. As a conclusion the automatically reported values for quantity of mold and factor of evenness distribution are enough to support the control of quality of blue cheese regarding the mold presence and distribution. [ABSTRACT FROM AUTHOR]

Certain fungi can produce secondary metabolites that are toxic, mycotoxins. Two groups of cheeses where fungi are used for ripening are the blue-veined cheeses (Penicillium roqueforti) and the "soft-ripened" cheeses (P. camemberti). An enzyme-linked immunosorbent assay was used to screen for the mycotoxin roquefortine C (ROQC) in 202 samples of cheeses sold in the United States. Of these 152 were blue-veined cheeses, 46 were soft-ripened cheeses and 4 were other varieties of mould-ripened cheeses. ROQC was not detected in any of the soft-ripened cheeses, at a limit of detection of 1.8 µg/kg. ROQC was found in 151 of 152 blue-veined cheeses. The maximum level found was 6,630 µg/kg (median 903 µg/kg, average of positives 1430 µg/kg, limit of quantitation 6.9 µg/kg). These levels are consistent with the levels found previously in blue-veined cheeses in the United Kingdom and Europe, which have generally been considered non-hazardous for human consumption. [ABSTRACT FROM AUTHOR]

Sleep is a conserved and essential behavior, but its mechanistic and functional underpinnings remain poorly defined. Through unbiased genetic screening in Drosophila, we discovered a novel short-sleep mutant we named argus. Positional cloning and subsequent complementation, CRISPR/Cas9 knock-out, and RNAi studies identified Argus as a transmembrane protein that acts in adult peptidergic neurons to regulate sleep. argus mutants accumulate undigested Atg8a(+) autophagosomes, and genetic manipulations impeding autophagosome formation suppress argus sleep phenotypes, indicating that autophagosome accumulation drives argus short-sleep. Conversely, a blue cheese neurodegenerative mutant that impairs autophagosome formation was identified independently as a gain-of-sleep mutant, and targeted RNAi screens identified additional genes involved in autophagosome formation whose knockdown increases sleep. Finally, autophagosomes normally accumulate during the daytime and nighttime sleep deprivation extends this accumulation into the following morning, while daytime gaboxadol feeding promotes sleep and reduces autophagosome accumulation at nightfall. In sum, our results paradoxically demonstrate that wakefulness increases and sleep decreases autophagosome levels under unperturbed conditions, yet strong and sustained upregulation of autophagosomes decreases sleep, whereas strong and sustained downregulation of autophagosomes increases sleep. The complex relationship between sleep and autophagy suggested by our findings may have implications for pathological states including chronic sleep disorders and neurodegeneration, as well as for integration of sleep need with other homeostats, such as under conditions of starvation.

Quantity of mold Penicillium roqueforti in blue cheese is a significant factor for cheese quality. Therefore it is important to have abilities for fast and accurate assessment of molds’ quantity. Computer vision is popular as fast and not so expensive techniques for monitoring of cheese quality parameters. Segmentation algorithms are widely used for images analysis in order to extract specific objects from background. When the result of segmentation is binary image then the algorithms are known as thresholding algorithms. This paper presents an approach for evaluation the quantity of mold Penicillium roqueforti on cut surface of blue cheese, based on images processing with thresholding algorithms in HSI (Hue Saturation Intensity) color space. Four trademarks of blue cheese are used for experiments. The images of cut surfaces of examined blue cheese are processed with application developed in NI LabView environment. All images are processed also with algorithm for mold distribution analysis in RGB color space which uses manual thresholding. The results for mold Penicillium roqueforti quantity which are calculated using developed application and algorithm for mold distribution in RGB color space, are compared. It is performed a correlation analysis for quantity of mold Penicillium roqueforti calculated with developed application versus quantity calculated by algorithm for mold distribution analysis in RGB color space. The calculated correlation coefficients are high for intensity and hue components (about 0.9) which show that the results are statistically significant. Because of this, developed application could be used for automatic control of blue cheese quality. The results show that developed application could be used in blue cheese quality control. [ABSTRACT FROM AUTHOR]

Drosophila blue cheese (bchs) encodes a BEACH domain adaptor protein that, like its human homolog ALFY, promotes clearance of aggregated proteins through its interaction with Atg5 and p62. bchs mutations lead to age-dependent accumulation of ubiquitinated inclusions and progressive neurodegeneration in the fly brain, but neither the influence of autophagy on bchs-related degeneration, nor bchs’ placement in the autophagic hierarchy have been shown. We present epistatic evidence in a well-defined larval motor neuron paradigm that in bchs mutants, synaptic accumulation of ubiquitinated aggregates and neuronal death can be rescued by pharmacologically amplifying autophagic initiation. Further, pharmacological rescue requires at least one intact BEACH-containing isoform of the two identified in this study. Genetically augmenting a late step in autophagy, however, rescues even a strong mutation which retains only a third, non-BEACH containing isoform. Using living primary larval brain neurons, we elucidate the primary defect in bchs to be an excess of early autophagic compartments and a deficit in mature compartments. Conversely, rescuing the mutants by full-length Bchs over-expression induces mature compartment proliferation and rescues neuronal death. Surprisingly, only the longest Bchs isoform colocalizes well with autophagosomes, and shuttles between different vesicular locations depending on the type of autophagic impetus applied. Our results are consistent with Bchs promoting autophagic maturation, and the BEACH domain being required for this function.HIGHLIGHTSThe autophagic adaptor blue cheese is placed in an epistatic hierarchy, using pharmacological and genetic modulation of bchs- motor neuron degeneration. An intact BEACH isoform can promote autophagic proliferation, and in primary larval brain neurons Bchs shuttles to different components of the autophagy machinery, dependent on the stimulus.

The occurrence and dietary exposure assessment of 16 mycotoxins, 6 biogenic amines (BAs), and 13 metallic elements in blue-veined cheeses (n = 46) is reported. Co-occurrence of mycophenolic acid (≤599 µg·kg−1) with roquefortine C (≤5454 µg·kg−1) was observed in 63% of the tested cheeses, while BAs were frequently present at concentrations between 0.2 and 717 mg kg−1. The concentrations of heavy metals in cheeses were very low. Chronic/acute exposure assessment based on consumption data from different European populations indicated that the levels of mycotoxins and heavy metals are safe to consumers, whereas, rather high hazard indexes (HI up to 0.77) were determined for BAs according to the worst-case scenario based on high consumption and 95th percentile occurrence. A more detailed acute dietary intake study indicated that histamine and tyramine were predominant among these BAs, reaching 27 and 41% of the acute oral intake reference doses.

Abstract: Blue cheese is commonly aged for 60 days at 10°C after curing. However, some manufacturers store blue cheese at 4°C and the effect of lower storage temperature on blue cheese final properties is unknown. Thus, the objective of this study was to determine the effect of storage temperature and time on blue cheese mechanical behaviors. Blue cheeses were stored at 4 or 10°C for 77 days after production. Composition and small‐ and large‐strain rheological behaviors were evaluated every 2 weeks of storage. Storage time had significant impact on blue cheese rheological behaviors; storage temperature did not. Large‐strain compressive force and viscoelastic moduli decreased with storage time, and the extent of nonlinear viscoelastic behavior increased. These results indicated that sample microstructure likely weakened and was more easily deformed as storage time increased. Overall, blue cheese can be stored at 4–10°C without significant changes to its composition or mechanical behavior. Practical applications: The results of this work can be used by blue cheese manufacturers to better understand the impact of storage time and temperature on blue cheese end quality. Manufacturers can take advantage of the effects of storage time on blue cheese mechanical behaviors to determine how long to age blue cheese to achieve the desired texture. [ABSTRACT FROM AUTHOR]

Ripening of blue-veined cheeses, such as the French Bleu and Roquefort, the Italian Gorgonzola, the English Stilton, the Danish Danablu or the Spanish Cabrales, Picón Bejes-Tresviso, and Valdeón, requires the growth and enzymatic activity of the mold Penicillium roqueforti, which is responsible for the characteristic texture, blue-green spots, and aroma of these types of cheeses. This filamentous fungus is able to synthesize different secondary metabolites, including andrastins, mycophenolic acid, and several mycotoxins, such as roquefortines C and D, PR-toxin and eremofortins, isofumigaclavines A and B, and festuclavine. This review provides a detailed description of the main secondary metabolites produced by P. roqueforti in blue cheese, giving a special emphasis to roquefortine, PR-toxin and mycophenolic acid, and their biosynthetic gene clusters and pathways. The knowledge of these clusters and secondary metabolism pathways, together with the ability of P. roqueforti to produce beneficial secondary metabolites, is of interest for commercial purposes. [ABSTRACT FROM AUTHOR]

In the annual reports of the European Food Safety Authority (EFSA), Yersinia enterocolitica (YE) is enumerated as the third most common enteric pathogen responsible for food poisonings. The objective of the paper was to determine the potential for Yersinia enterocolitica growth in blue cheese and in blue cheese with a probiotic ( Lactobacillus acidophilus LA-5®) . The experiment was carried out with five different cheese batches. The potential of YE growth was determined at 3, 6, 9, 12 and 15 °C in ten time intervals up to 480 h of storage. The initial contamination level was set at ~10 cfu/g YE. The studies demonstrated that at lower temperatures there was a systematic increase in the number of cells throughout the storage period, whereas at higher temperatures stationary and die-off phases were observed. By comparing the increase in the number of YE cells in both cheese varieties, it may be observed that at 6, 9 and 12 °C the number of YE cells was lower in blue cheese with probiotic than in blue cheese at each stage of the experiment although it did not guarantee the microbiological safety of the product. [ABSTRACT FROM AUTHOR]

Brevibacterium linens is an important species in dairy products rendering a specific taste and aroma to numerous smear ripened and blue veined cheeses due to proteolysis. However, the presence of the species in South African blue veined cheeses is undesirable and consumers demand the product void of the species. Accordingly, numerous methods including microbial inhibition using fungi and bacterial probiotic cultures with possible inhibitory effects were applied in an attempt to inhibit the species. None of the fungi, however, proved to be successful, whereas Lactobacillus rhamnosus and Bifidobacterium lactis, two typical probiotic species applied in dairy products, showed inhibitory effects against B. linens when tested using the spot-on-lawn assay.

Varieties of blue veined cheese were analyzed regularly during different stages of manufacturing and ripening to determine the origin of contaminating the yeasts present in them, their population diversity and development until the end of the storage. Yeast diversity and development in the inner and outer core of the cheeses during ripening were also compared. Air samples revealed few if any yeasts whereas the samples in contact with the equipment and the surroundings revealed high number of yeasts, implicating it as the possible main source of post-pasteurization contamination, as very few yeasts were isolated from the milk and cheese making process itself. Samples from the inner and outer core of the maturing cheeses had typical survival curves. The number of yeasts on the outer core was about a 100-fold more than of those in the inner core. The most abundant yeasts isolated from the environment and ripening cheeses were identified as Debaryomyces hansenii, Saccharomyces cerevisiae, Torulaspora delbrueckii, Trichosporon beigelii, Candida versatilis and Cryptococcus albidus, while the yeasts Candida zeylanoides and Dekkera anomala were additionally isolated from the environment. Yeasts were present in high number, making their occurrence in blue-veined cheeses meaningful.

This paper examines the impact of Geographical Indications in cheese mountain areas, exploring their potential to contribute to landscape and environmental sustainability by drawing on field work and documental evidences from Cabrales (Asturias, NW Spain). The Cabrales mountain, nestled in the Picos de Europa National Park, embraces a millenary culture linked to the elaboration of an intense flavor blue cheese. The commercial success of this cheese motivated, 40 years ago, the creation of the Cabrales Protected Designation of Origin (PDO). From that moment on, the implementation of certain control measures that affect the production process, together with the increase in demand, led to the disappearance of small producers and to the intensification of livestock management practices. Cheese producers took the opportunity that the PDO label gave them, and the PDO provided the context in which cheese production became an effective barrier against the degradation of the rural system. However, nowadays the intensification of livestock management practices constitutes the main threat to landscape and environmental conservation. Therefore, Local administrators and stakeholders should consider the need to reinforce the idea of a product whose quality is linked to environmental and landscape sustainability through the maintenance of the traditional extensive management practices. • Cabrales cheese production acts as a barrier against the demotion of the rural system. • Increased demand caused the emergence of differences in cheese production. • Extensive production is linked to a superior cheese that increases brand prestige. • Intensification of livestock management practices hinders landscape conservation. [ABSTRACT FROM AUTHOR]

A new chromogenic array for the identification and classification of blue cheeses has been developed. It is based on the response of a chromogenic array composed of five sensing materials prepared by the incorporation of pH indicators to MCM-41 and alumina. Four blue cheeses were tested: Roquefort, Blue Stilton, blue cheese with leaves and blue cheese spread. The colour modulations of the chromogenic array were processed by the principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). The statistical PCA analysis showed different responses to each cheese. PLS-DA models were developed by incorporating the data measured at diverse times, and this approach allowed us to obtain a perfect classification of all five cheeses in 5.5 h. The results suggest that chromogenic arrays and optoelectronic noses can be a suitable approach to develop simple systems to classify blue cheeses and of potential use for the detection of food fraud. [ABSTRACT FROM AUTHOR]

In this study, four different types of mould-ripened Civil cheese were manufactured. A defined (nontoxigenic) strain of a Penicillium roqueforti ( SC 509) was used as secondary starter for the manufacture of mould-ripened Civil cheese with and without addition of the whey cheese Lor; in parallel, secondary starter-free counterparts were manufactured. A total of 83 compounds were identified. Ketones, alcohols and esters were the principal classes of volatile components. Principal component analysis of the headspace volatiles grouped cheeses by age and type. P. roqueforti inoculated cheese was clearly separated from the other cheeses at 180 days of ripening, and these cheeses were characterised with high levels of ketones (e.g., 2-butanone, 2-heptanone). Differences in the panel scores between the cheese samples were not significant during the first stage of ripening (up to 60 days); as ripening proceeded, these differences were become evident and P. roqueforti inoculated cheeses received higher scores than others. Addition of Lor in the manufacture of mould-ripened Civil cheese caused lower points by the sensory panel, and the cheese inoculated with P. roqueforti and Lor-free was the best type of mould-ripened Civil cheese. The results showed that the use of P. roqueforti in the manufacture of mould-ripened Civil cheese has significant impact on the volatile profiles and sensory attributes. [ABSTRACT FROM AUTHOR]

A study concerning the lipidic fraction in relation to esterified fatty acids composition, free fatty acids contents, triglyceride analysis and gross composition characteristics from artisanal blue cheeses made in the Principado de Asturias was carried out. Gas chromatography with capilar column and flow splitter was used for the esterified and free fatty acids analysis and flow splitter with programmed temperature vaporation (PTV) for the triglyceridic study. The results obtained for the esterified fatty acids, free fatty acids and triglycerides showed differences in each variety of cheese studied. In Cabrales and Gamonedo cheese were more deepen. Those differences found it could be to the milk and rennet used and the manufacture method of the curd and metabolic activity of the Penicillum roqueforti which it influenced by the ripening conditions (temperature and moisture) of the cheeses.

Blue cheese is a semi-soft ripened cheese that involves the growth of Penicillium roqueforti in the ripening process. Cheese has a longer shelf life compared to raw milk and the production of cheese will give added value to the finished product, which, therefore, can benefit local dairy farmers in Indonesia. The objective of this study was to produce a new variant of blue cheese which was made from a mixture of fresh cow's milk (Frisian Holstein cow) and skimmed milk powder and which had a high vitamin B12, folic acid, and iron content. Blue cheeses for this study were made by milk fermentation with the addition of a nonpathogenic strain of Klebsiella pneumoniae in the cheese preparation and fortification of folic acid and iron. This study showed that blue cheeses had been successfully made from a mixture of fresh cow's milk and skimmed milk at a ratio of 1:1 and acceptable by 42 untrained panelists. Compared to the commercial blue cheese, the addition of K. pneumoniae (0.8% v/v) and fortification (0.08 g L-1 of premix) had positive effects in increasing the amount of vitamin B12, folic acid, and iron up to 2.7, 13.64, and 102.86 ppm on dry-weight basis, respectively. However, blue cheese made without K. pneumoniae was the most preferred and had the highest scores for texture, taste and aroma.

Penicillium roqueforti plays an important role in the ripening of blue-veined cheeses, mostly due to lactic acid consumption and to its extracellular enzymes. The strong activity of P. roqueforti proteinases may bring about cheese over-ripening. Also, free amino acids at high concentrations serve as substrates for biogenic amine formation. Both facts result in shorter product shelf-life. To prevent over-ripening and buildup of biogenic amines, blue-veined cheeses made from pasteurized ovine milk were high-pressure treated at 400 or 600 MPa after 3, 6, or 9 wk of ripening. Primary and secondary proteolysis, biogenic amines, and sensory characteristics of pressurized and control cheeses were monitored for a 90-d ripening period, followed by a 270- d refrigerated storage period. On d 90, treatments at 400 MPa had lowered counts of lactic acid bacteria and P. roqueforti by less than 2 log units, whereas treatments at 600 MPa had reduced lactic acid bacteria counts by more than 4 log units and P. roqueforti counts by more than 6 log units. No residual α-casein (CN) or κ-CN were detected in control cheese on d 90. Concentrations of β-CN, para-κ-CN, and γ-CN were generally higher in 600 MPa cheeses than in the rest. From d 90 onwards, hydrophilic peptides were at similar levels in pressurized and control cheeses, but hydrophobic peptides and the hydrophobic-to-hydrophilic peptide ratio were at higher levels in pressurized cheeses than in control cheese. Aminopeptidase activity, overall proteolysis, and free amino acid contents were generally higher in control cheese than in pressurized cheeses, particularly if treated at 600 MPa. Tyramine concentration was lower in pressurized cheeses, but tryptamine, phenylethylamine, and putrescine contents were higher in some of the pressurized cheeses than in control cheese. Differences in sensory characteristics between pressurized and control cheeses were generally negligible, with the only exception of treatment at high pressure level (600 MPa) at an early ripening stage (3 wk), which affected biochemical changes and sensory characteristics. [ABSTRACT FROM AUTHOR]

The aim of this work was quality analyse of cheese samples with mould Penicilium requeforti inside dough. The samples of cheese were evaluated in day of production and day of packaging after 22 days of maturation during 10 months. From the physico-chemical properties were monitored mainly changes of dry matter, fat content, active acidity, fat content in dry matter and content of NaCl. From microbiological properties were monitored especially coliform bacteria. Process of maturation influenced from the physico-chemical properties mainly fat content and dry matter of cheese, which increased to the desired value. The active acidity, fat in dry matter and content of NaCl were changed during maturation of at least. Presence of coliform bacteria as indicator of hygiene during production was not detected in any samples of evaluated cheese. [ABSTRACT FROM AUTHOR]

Abstract: A total of 52 Italian and French commercial cheeses were analysed for fatty acid composition and conjugated linoleic acid (CLA) concentration. The cheeses were first grouped according to the ruminant species of the milk used in manufacturing, then according to the following criteria: (1) cheeses obtained from milk of the same ruminant species but using different production technologies; (2) cheeses produced from milk of different ruminant species but through similar cheesemaking processes. Comparative studies of fatty acid composition and CLA levels in the different cheese classes were carried out. In our study, the arrangement of the ruminant species according to the increasing CLA concentration in cheese was: goat=cow

The definition of a blue cheese technology manufactured with cow milk was carried out in a cheese factory. With this purpose, 6 trails tests and 12 experiment tests of 300 L each one, were elaborated in order to know the fundamental process parameters and to extract the indispensable information for the preparation of the process standard and its characterization were also determined. [ABSTRACT FROM AUTHOR]

Abstract: High quality local varieties of blue-veined cheese are made in the villages of the valleys of Cabrales, Valdeón and Bejes–Tresviso in North Spain. Penicillium roqueforti strains have been isolated from each of those blue cheeses and compared with the collection strain P. roqueforti CECT 2905 (ATCC 10110) and a strain ‘Valdeón-industrial’ used for large scale production of Valdeón cheese. Using molecular genetics techniques and 5.8S and 18S rRNAs and the D1–D2 regions of 28S rRNA all strains were identified as authentic P. roqueforti. These strains from local varieties of blue cheese could be distinguished from the Valdeón-industrial strain and the control strain CECT 2905 by the mitochondrial DNA restriction pattern. The industrial strain showed high levels of aspartylprotease AspA, whereas the culture collection strain showed barely detectable levels of this enzyme, as shown by proteolysis tests and by immunodetection with anti-AspA antibodies. The lipolytic activity was similar in the strains isolated from the three types of local blue cheeses. The strains isolated from the local varieties of the blue cheese produced moderate levels of PR toxin, whereas the Valdeón-industrial strains showed a higher content of this mycotoxin. All strains (except the control strain CECT 2905) showed similar levels of roquefortine C. The antitumoral compound andrastin A was produced by all strains at different levels. P. roqueforti CECT 2905 showed high ability to synthesize this compound. Andrastin A was present in all industrial and local varieties of blue cheese. The content of andrastin A was similar to that of other well-known blue cheeses from France and Denmark. [Copyright &y& Elsevier]

Changes in the concentrations of free fatty acids in Niva cheese were monitored over the ripening period. Fatty acids were analyzed as methyl esters using gas chromatography with flame ionization detection. Identification has been carried out by comparison of the retention times with those of standard substances. Methanol esterification method using potassium hydroxide catalysis was used for preparing the sample of the fatty acids. The method is simple in respect to instrumentation and chemicals. It can be applied directly to the cheese matrix, which significantly decreases the time for sample preparation. There were total of 30 fatty acids identified in the cheese. Capric, myristic, palmitic, stearic and oleic acids represented the largest proportion of acid content and the most significant changes during ripening.

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Abstract: Evidence for the occurrence of ochratoxin A in blue cheeses is reported for the first time. The development of an accurate and reliable procedure for the extraction of OTA from cheese, as well as the availability of a new sensitive HPLC-FLD method, has allowed us to determine ochratoxin A in complex matrices such as cheeses, even at very low levels (LOD in cheese: 0.02μg/kg). A good linearity for the OTA concentration, between 0.2 and 2.5μg/kg, was obtained and no matrix effect was observed in the same concentration range. The mean recovery for OTA was 97%, while the average RSD was 3%, within a spiking range of 0.5–2.0μg/kg. Although the OTA contamination levels found in blue cheeses were very low, occurrence of ochratoxin A in such products opens a new issue for risk assessment and quality control, as far as finding the origin of the OTA contamination and ways to prevent it. [Copyright &y& Elsevier]

Were used four strains of Penicillium camemberti, named as R1, R2, R3 and R4, previously obtained and screening. Spore suspension were prepared with each one, evaluated in the laboratory for viability, bacterial contamination, total coliform, proteolytic and lipolytic capacity. Spore suspension from the different strains presented good viability, proteolytic and lipolytic activity. Gorgonzola cheese were manufactured in industry scal with the suspensions and evaluated for fat content in dry basis, moisture and sensory evaluation. In all cases were covered the quality requirements for the product. Sensory evaluation of cheese manufactured with strains R1 y R2 show excellent qualification. In the case of strains R3 y R4 the cheese were classified as aceptable. [ABSTRACT FROM AUTHOR]

In the present study, a fast and sensitive method for the quantification of ochratoxin A in two lipidicproteic food matrices has been developed. In particular, the sample preparation procedure has been optimized for dry-cured meat products and blue cheeses and tested for several validation parameters (LOD, LOQ, recovery, repeatability and within-laboratory precision). The procedure has been then applied to several dry-cured meat products and blue cheeses from the market. Ochratoxin A has been occasionally found in dry-cured and smoked ham from the market and the contamination occurred both in the outer and in the inner part of the products. Concerning the blue cheese, the occurrence of ochratoxin A is reported for the first time: OTA was occasionally found at low levels (0.1–3 μg/kg) in commercial samples of Roquefort from France and Gorgonzola from Italy, opening a new issue for risk assessment and quality control. [ABSTRACT FROM AUTHOR]

Abstract: The chemical and microbial qualities, including fungal flora, of 30 samples of Kuflu cheese randomly purchased from different markets in Turkey were investigated. The gross composition of the cheese samples ranged between 37.65–53.65% moisture, 6.21–40.09% fat-in-dry matter, 4.70–10.07% salt-in-moisture and 26.18–44.85% protein. The mean pH value of the cheeses was 6.29±0.28 and pH values ranged from 5.52 to 7.22. Variations between the samples in terms of their gross composition suggested a lack of quality standards in cheesemilk, cheesemaking procedure and ripening conditions. The levels of main microbial groups including total mesophilic and coliform bacteria, yeasts and moulds and the presence of some potentially pathogenic microorganisms (E. coli, Salmonella spp. and Staphylococcus aureus) were determined. The high numbers of all microbial groups and presence of potentially pathogenic organisms in the cheese samples suggested that the production and maturation of Kuflu cheese should be improved by better hygiene. Moulds at the cheese surface were isolated and identified. A total of 24 different mould species were detected and the genus most frequently isolated was Penicillium spp. which represented 70.25% of total isolates. Penicillium commune, P. roqueforti and P. verrucosum were the most abundant species in the cheeses sampled. The other dominant fungal groups were Geotrichum candidum, Penicillium expansum and P. chrysogenum. Other genera isolated from the cheese were Acremonium, Alternaria, Aspergillus, Cladosporium, Geotrichum, Mucor, Rhizopus and Trichoderma. The potentially toxigenic species, including some Penicillum spp. and Aspergillus flavus, were also detected. [Copyright &y& Elsevier]

Degradation of dextran beads was observed when the water-soluble fraction of a blue cheese extract was applied to the top of a Sephadex G-150 or G-200 column. This phenomenon suggests the presence of a specific enzyme that can hydrolyze dextran. After removal of casein components from the blue cheese fraction, ammonium sulfate treatment and gel filtration chromatography were performed to isolate the enzyme fraction. The enzymatic products were analyzed by thin-layer chromatography and gel filtration chromatography and identified as isomaltooligosaccharides. The isoelectric point of this enzyme fraction was approximately 4.9, as determined by isoelectric focusing using Rotofor, and the molecular weight of the fraction was 65 kDa, as estimated by sodium dodecyl sulfate (SDS)-PAGE. Optimum pH for enzymatic activity was 5.0 to 5.3. A partial N-terminal amino acid sequence of 20 residues was determined to be ATPDEWRSRSIYFMLTDRGA from an enzyme fraction further purified by ion-exchange chromatography and native PAGE. This sequence showed a maximum homology of 80% with α-amylase or Taka amylase that originated from various microorganisms. [ABSTRACT FROM AUTHOR]

Relationships between odour and flavour attributes of six blue-type cheeses and their volatile compounds, free amino acids (FAA), free fatty acids (FFA) and gross compositional constituents were determined. Relationships were also determined between texture attributes and gross compositional constituents. Fifteen assessors described the odour, flavour, appearance and texture profile of cheeses. Volatile compounds were isolated using a model-mouth apparatus. FAA, FFA and gross compositional constituents were determined using standard methods. Using Partial Least Squares Regression two odour and five flavour attributes were found to correlate with subsets of volatile compounds, FAA, FFA and gross compositional constituents. For example, “mouldy” flavour was positively correlated with the concentrations of pH 4.6-soluble nitrogen and 2-pentanone, 2-heptanone, 2-octanone and 2-nonanone. Three texture attributes were found to correlate with subsets of gross compositional constituents. For example, “crumbly” texture was positively correlated with concentration of fat and protein and negatively correlated with levels of moisture in the non-fat substance and moisture. [Copyright &y& Elsevier]

Profiles of oxygen in Danablu cheese at the age of 1–19 weeks were measured by using an oxygen microsensor. In a cheese ripened for 1 week, the percentage oxygen saturation decreased to 70% at 0.25-mm depth and further to 50% at 4-mm depth.In a more extended determination of oxygen profiles, the spatial and temporal development in the oxygen level was investigated at 5-mm resolution at the center and 5 mm from the edge of the cylindrical cheeses at a depth of 45 mm. Average oxygen saturation decreased from 63% to 0.1% at the centre and from 69% to 0.1% at the edge in cheeses from 1 to 19 weeks. In the cheeses ripened for more than 3 weeks, oxygen was not detectable, except for a surface layer of 0.25 mm and in apparent small air pockets within the cheese containing about 3% saturated oxygen. [ABSTRACT FROM AUTHOR]

The graphical abstract will be provided in case the paper is accepted for publication. [Display omitted] • Feeding chitosan or peptidoglycan significantly increased adult bee survivorship. • They also reduced N. ceranae infection. • Chitosan lowered immune/stress-related gene expression early and late infection. • Peptidoglycan raised immune/stress-related gene expression early and late infection. • Reduced infection may be due to the compounds altering honey bee gene expression. Nosema ceranae is a microsporidian parasite that causes nosema disease, an infection of the honey bee (Apis mellifera) midgut. Two pathogen-associated molecular patterns (PAMPs), chitosan and peptidoglycan, and N. ceranae spores were fed to worker bees in sucrose syrup and compared to non-inoculated and N. ceranae -inoculated bees without PAMPs. Both chitosan and peptidoglycan significantly increased bee survivorship and reduced spore numbers due to N. ceranae infection. To determine if these results were related to changes in health status, expression of the immune-related genes, hymenoptaecin and defensin2, and the stress tolerance-related gene, blue cheese, was compared to that of control bees. Compared to the inoculated control, bees with the dose of chitosan that significantly reduced N. ceranae spore numbers showed lower expression of hymenoptaecin and defensin2 early after infection, higher expression mid-infection of defensin2 and lower expression of all three genes late in infection. In contrast, higher expression of defensin2 early in the infection and all three genes late in the infection was observed with peptidoglycan treatment. Changes late in the parasite multiplication stage when mature spores would be released from ruptured host cells are less likely to have contributed to reduced spore production. Based on these results, it is concluded that feeding bees chitosan or peptidoglycan can reduce N. ceranae infection, which is at least partially related to altering the health of the bee by inducing immune and stress-related gene expression. [ABSTRACT FROM AUTHOR]

Yeasts constitute an important part of cheeses, and especially the artisanal ones. The current study reviews the occurrence of yeasts in different cheese varieties and the role of yeasts in cheesemaking process. The use of molecular methods for identification and strain typing has extended the knowledge for yeast diversity in cheeses. For the study of the occurrence of yeasts in different cheese types, seven categories are used, that is: 1) hard, 2) semi-hard, 3) soft, which includes soft pasta-filata and whey cheeses, 4) white brined cheeses, 5) mould surface ripened, 6) bacterial surface ripened cheeses, and 7) blue cheeses. For some cheese types, yeasts are the main microbial group, at least for some part of their ripening process, while for some other types, yeasts are absent. Differences between industrially manufactured cheeses and artisanal cheeses have specified. Artisanal cheeses possess a diverse assortment of yeast species, mainly belonging to the genera Candida , Clavisporalus , Cryptococcus , Debaryomyces , Geotrichum , Issatchenkia , Kazachstania , Kluyveromyces , Kodemaea , Pichia , Rhodotorula , Saccharomyces , Saturnispora , Torulaspora , Trichosporon , Yarrowia and ZygoSaccharomyces . The role of the yeasts for selected cheeses from the seven cheese categories is discussed., Competing Interests: Conflict of interest: The author hereby declares that there is no conflict of interest that could arise., (© 2021 the Author(s), licensee AIMS Press.)

• Self-organizing maps with entropy-based features outperformed linear PLS-DA. • Alcohols were found to be highly effective discriminant compounds for blue cheeses. • Esters, hydrocarbons, and ketones also discriminated blue cheese varieties. • 2,6-dimethylpyridine and 1-nonene were newly reported in blue cheese. • Danablu and Roquefort volatiles were most different among blue cheese varieties. Understanding which volatile compounds discriminate between products can be useful for quality, innovation or product authenticity purposes. As dataset size and dimensionality increase, linear chemometric techniques like partial least squares discriminant analysis and variable identification (PLS-DA-VID) may not identify the most discriminant compounds. This research compared the performance of self-organizing maps and entropy-based feature selection (SOM-EFS) and PLS-DA-VID to identify discriminant compounds in 17 blue cheese varieties. A total of 172 volatiles were detected using headspace solid phase microextraction, gas chromatography and mass spectrometry, including 1-nonene and 2,6-dimethylpyridine, which were newly identified in blue cheese. Despite SOM-EFS selecting only 14 volatiles compared to 78 for PLS-DA-VID, SOM-EFS proved more effectively discriminant and improved the median five-fold cross-validated prediction accuracy of the model to 0.94 compared to 0.82 for PLS-DA-VID. These findings introduce SOM-EFS as a powerful non-linear exploratory data analysis approach in the field of volatile analytical chemistry. [ABSTRACT FROM AUTHOR]

Sleep is a conserved and essential behavior, but its mechanistic and functional underpinnings remain poorly defined. Through unbiased genetic screening in Drosophila , we discovered a novel short-sleep mutant we named argus . Positional cloning and subsequent complementation, CRISPR/Cas9 knock-out, and RNAi studies identified Argus as a transmembrane protein that acts in adult peptidergic neurons to regulate sleep. argus mutants accumulate undigested Atg8a(+) autophagosomes, and genetic manipulations impeding autophagosome formation suppress argus sleep phenotypes, indicating that autophagosome accumulation drives argus short-sleep. Conversely, a blue cheese neurodegenerative mutant that impairs autophagosome formation was identified independently as a gain-of-sleep mutant, and targeted RNAi screens identified additional genes involved in autophagosome formation whose knockdown increases sleep. Finally, autophagosomes normally accumulate during the daytime and nighttime sleep deprivation extends this accumulation into the following morning, while daytime gaboxadol feeding promotes sleep and reduces autophagosome accumulation at nightfall. In sum, our results paradoxically demonstrate that wakefulness increases and sleep decreases autophagosome levels under unperturbed conditions, yet strong and sustained upregulation of autophagosomes decreases sleep, whereas strong and sustained downregulation of autophagosomes increases sleep. The complex relationship between sleep and autophagy suggested by our findings may have implications for pathological states including chronic sleep disorders and neurodegeneration, as well as for integration of sleep need with other homeostats, such as under conditions of starvation., Competing Interests: JB, MS, CP, CQ, CS, AK No competing interests declared, AS Reviewing editor, eLife, (© 2021, Bedont et al.)

The occurrence and dietary exposure assessment of 16 mycotoxins, 6 biogenic amines (BAs), and 13 metallic elements in blue-veined cheeses (n = 46) is reported. Co-occurrence of mycophenolic acid (≤599 µg·kg−1) with roquefortine C (≤5454 µg·kg−1) was observed in 63% of the tested cheeses, while BAs were frequently present at concentrations between 0.2 and 717 mg kg−1. The concentrations of heavy metals in cheeses were very low. Chronic/acute exposure assessment based on consumption data from different European populations indicated that the levels of mycotoxins and heavy metals are safe to consumers, whereas, rather high hazard indexes (HI up to 0.77) were determined for BAs according to the worst-case scenario based on high consumption and 95th percentile occurrence. A more detailed acute dietary intake study indicated that histamine and tyramine were predominant among these BAs, reaching 27 and 41% of the acute oral intake reference doses. [ABSTRACT FROM AUTHOR]

Drosophila blue cheese ( bchs ) encodes a BEACH domain adaptor protein that, like its human homolog ALFY, promotes clearance of aggregated proteins through its interaction with Atg5 and p62. bchs mutations lead to age-dependent accumulation of ubiquitinated inclusions and progressive neurodegeneration in the fly brain, but neither the influence of autophagy on bchs -related degeneration, nor bchs' placement in the autophagic hierarchy have been shown. We present epistatic evidence in a well-defined larval motor neuron paradigm that in bchs mutants, synaptic accumulation of ubiquitinated aggregates and neuronal death can be rescued by pharmacologically amplifying autophagic initiation. Further, pharmacological rescue requires at least one intact BEACH-containing isoform of the two identified in this study. Genetically augmenting a late step in autophagy, however, rescues even a strong mutation which retains only a third, non-BEACH containing isoform. Using living primary larval brain neurons, we elucidate the primary defect in bchs to be an excess of early autophagic compartments and a deficit in mature compartments. Conversely, rescuing the mutants by full-length Bchs over-expression induces mature compartment proliferation and rescues neuronal death. Surprisingly, only the longest Bchs isoform colocalizes well with autophagosomes, and shuttles between different vesicular locations depending on the type of autophagic impetus applied. Our results are consistent with Bchs promoting autophagic maturation, and the BEACH domain being required for this function., Highlights: The autophagic adaptor blue cheese is placed in an epistatic hierarchy, using pharmacological and genetic modulation of bchs - motor neuron degeneration. An intact BEACH isoform can promote autophagic proliferation, and in primary larval brain neurons Bchs shuttles to different components of the autophagy machinery, dependent on the stimulus.

This study was carried out to determine the cholesterol removal rate and resulting changes in sensory aspects and fatty acid and amino acid productions in reduced-cholesterol Blue cheese, made by cream separation followed by 10% crosslinked β-cyclodextrin (β-CD) treatment, ripened for 8 weeks at 10°C, and stored for 4 weeks at 4°C. The cholesterol removal from the cheese was 92.8%. The TBA value was significantly increased up to 6 week ripening and maintained thereafter in both treatments. The production of short-chain fatty acids (FFAs) significantly increased during the ripening and storage periods up to 10 weeks and slightly decreased thereafter in both control and β-CD-treated cheeses. During ripening and storage periods, the production of total amino acids increased significantly. The quantity of short-chain FFAs and total amino acids released between treatments during ripening was not different. In rheological properties, brittleness score was significantly different between control and cholesterolreduced cheese at 8 and 12 week ripening and storage. In sensory analysis, appearance, flavor, taste and texture properties were not significantly different between control and cholesterol-reduced Blue cheese after 8 week ripening and 4 week storage periods. In addition, overall acceptability in the cholesterol-reduced cheese was closely similar to that in control. On the basis of our results, we conclude that the crosslinked β-CD-treated cream Blue cheese showed a sufficient cholesterol removal rate and no adverse changes in sensory characteristics. [ABSTRACT FROM AUTHOR]