Invited review: Bioactive compounds produced during cheese ripening and health effects associated with aged cheese consumption

Metabolomic profiling of Fiore Sardo cheese: Investigation of the influence of thermal treatment and ripening time using univariate and multivariate classification techniques

The effect of different sub-pasteurization heat treatments and different ripening times was investigated in this work. The metabolite profiles of 95 cheese samples were analyzed using GC-MS in order to determine the effects of thermal treatment (raw milk, 57 °C and 68 °C milk thermization) and ripening time (105 and 180 days). ANOVA test on GC-MS peaks complemented with false discovery rate correction was employed to identify the compounds whose levels significantly varied over different ripening times and thermal treatments. The univariate t-test classifier and Partial Least Square Discriminant Analysis (PLS-DA) provided acceptable classification results, with an overall accuracy in cross-validation of 76% for the univariate model and 72% from the PLS-DA. The metabolites that mostly changed with ripening time were amino acids and one endocannabinoid (i.e., arachidonoyl amide), while compounds belonging to the classes of biogenic amines and saccharides resulted in being strongly affected by the thermization process.

Effect of supercritical carbon dioxide on protein structure modification and antimicrobial peptides production of Mongolian cheese and its in vitro digestion

The aim of this research was to investigate the effects of supercritical carbon dioxide (SC-CO2) treatment on protein structure in Mongolian cheese. The peptides during the digestive process of the SC-CO2 treated cheese were also studied. SC-CO2 technology was utilized to treat Mongolian cheese at three temperatures (45, 55 and 65 °C) and three pressures (7.5, 12.5 and 17.5 MPa). The results of fluorescence, ultraviolet-visible, Fourier transform infrared spectroscopy and free sulfhydryl groups showed that SC-CO2, particularly at 65 °C and 17.5 MPa, modified the protein structure in Mongolian cheese effectively. The data of LC-MS/MS-based peptidomics showed that the content of antimicrobial peptides found in the SC-CO2 treated Mongolian cheese was 1.55 times that of the untreated Mongolian cheese; the content of unique antimicrobial peptides in the digested SC-CO2 treated Mongolian cheese was 1.46 times that of the digested untreated Mongolian cheese, which proved that SC-CO2 could help produce antimicrobial peptides in cheese not only during the process of SC-CO2 treatment but during subsequent simulated gastrointestinal digestion as well. In conclusion, SC-CO2 could be considered a promising method to develop cheese products with potential health benefits.

Effect of ripening time on the content of bioactive peptides and fatty acids profile of Artisanal Coalho cheese

The present study aimed to investigate the influence of ripening on the physicochemical, microbiological aspects, and fatty acid profile of Artisanal Coalho Cheeses and to detect if there are peptides with bioactive potential in their composition. Artisanal Coalho Cheese samples were kindly provided by a dairy farm located in Brazil in the Rio Grande do Norte state. A completely randomized design was adopted, with four maturation periods (0, 30, 45, and 60 days). Physicochemical traits (pH, total solids, moisture, non-fat solids, fat in total solids, protein, ash, fatty acid profile) and microbiological characterization (Salmonella sp, Listeria monocytogenes, total and thermotolerant coliforms, Staphylococcus aureus) were analyzed on cheese samples. Additionally, assays were performed for antioxidant and antihypertensive bioactivity through ACE and antimicrobial inhibition of the peptides extracted from the samples. There was a linear increase in total solids and ash content and a decrease in moisture content with increasing maturation time. The matured cheese samples had a lower pH than fresh Artisanal Coalho Cheese. Twenty-seven fatty acids were identified in the cheeses: 15 saturated, 07 monounsaturated, and 05 polyunsaturated, with a linear reduction of essential fatty acids (n6 and n3) during maturation. The microbiological quality of the cheeses was satisfactory, with an absence of undesirable bacteria in 92% of the cheese samples. Water-soluble peptide fractions from all periods tested showed antioxidant and antihypertensive potential with ACE control, and the maturation process potentiated these capacities, with a decline in these activities observed at 60 days. The antimicrobial activity against Gram-positive and Gram-negative bacteria increased with maturation, reaching better results until 60 days. The maturation process on wooden planks in the periods of 30, 45, and 60 days allows the production of Artisanal Coalho Cheese of an innovative character, safe to consumers from the microbiological point of view, with differentiated physicochemical and functional characteristics and good quality of lipid fraction compared to fresh cheese, enabling the addition of value to the dairy chain.

Exploring the Impact of French Raw-Milk Cheeses on Oxidative Process Using Caenorhabditis elegans and Human Leukocyte Models

Fermented foods, including cheeses, have garnered increased interest in recent years for their potential health benefits. This study explores the biological properties of eight French raw-milk cheeses-goat cheese, Saint-Nectaire, Cantal, Bleu d'Auvergne, Roquefort, Comté, Brie de Meaux, and Epoisses-on oxidative processes using both in vivo (Caenorhabditis elegans) and in vitro (human leukocytes) models. A cheese fractionation protocol was adapted to study four fractions for each cheese: a freeze-dried fraction (FDC) corresponding to whole cheese, an apolar (ApE), and two polar extracts (W40 and W70). We showed that all cheese fractions significantly improved Caenorhabditis elegans (C. elegans) survival rates when exposed to oxidative conditions by up to five times compared to the control, regardless of the fractionation protocol and the cheese type. They were also all able to reduce the in vivo accumulation of reactive oxygen species (ROS) by up to 70% under oxidative conditions, thereby safeguarding C. elegans from oxidative damage. These beneficial effects were explained by a reduction in ROS production up to 50% in vitro in human leukocytes and overexpression of antioxidant factor-encoding genes (daf-16, skn-1, ctl-2, and sod-3) in C. elegans.

Occurrence, Risk Implications, Prevention and Control of CIT in Monascus Cheese: A Review

Monascus is a filamentous fungus that has been used in the food and pharmaceutical industries. When used as an auxiliary fermenting agent in the manufacturing of cheese, Monascus cheese is obtained. Citrinin (CIT) is a well-known hepatorenal toxin produced by Monascus that can harm the kidneys structurally and functionally and is frequently found in foods. However, CIT contamination in Monascus cheese is exacerbated by the metabolic ability of Monascus to product CIT, which is not lost during fermentation, and by the threat of contamination by Penicillium spp. that may be introduced during production and processing. Considering the safety of consumption and subsequent industrial development, the CIT contamination of Monascus cheese products needs to be addressed. This review aimed to examine its occurrence in Monascus cheese, risk implications, traditional control strategies, and new research advances in prevention and control to guide the application of biotechnology in the control of CIT contamination, providing more possibilities for the application of Monascus in the cheese industry.

Feeding Dairy Goats Dehydrated Orange Pulp Improves Cheese Antioxidant Content

Agroindustrial by-products constitute an alternative source of feed livestock, and their use contributes to the sustainability of livestock systems and the circular bioeconomy. The effects of replacing cereal (0%, 40%, and 80%) with dehydrated orange pulp (DOP) in the diet of goats on the antioxidant and fatty acid (FA) contents of cheeses were evaluated. For a more suitable understanding of the role of coagulant enzymes in establishing the properties of the cheese, the effect of milk-clotting with animal and vegetable rennet was also analysed. The rennet did not substantially affect the FA or the antioxidant compounds, and the use of DOP did not affect the FA contents. However, the α-tocopherol levels, total phenolic compounds (TPC), and total antioxidant capacity (TAC) in cheeses increased as the percentage of DOP replacing cereals increased. Moreover, the high correlation obtained between the TAC and the TPC (r = 0.73) and α-tocopherol (r = 0.62) contents indicated the important role played by these compounds in improving the antioxidant capacity of the cheese. In conclusion, DOP is a suitable alternative to cereals in the diet of goats and improves the antioxidant status of the cheese produced.

Milk-based culture of Penicillium camemberti and its component oleamide affect cognitive function in healthy elderly Japanese individuals: a multi-arm randomized, double-blind, placebo-controlled study

Dairy products and fermented foods have a reported association with maintained cognitive function. Camembert cheese, a dairy product fermented by the white mold Penicillium camemberti, has also been shown to enhance cognitive function in vivo. Oleamide, derived from the fermentation of the white mold, is a candidate for an active component, and expected to improve both cognitive function and sleep conditions. Thus, this study investigated whether the milk-based culture of white mold (MCW), and oleamide, could improve cognitive function and sleep state clinically. A multi-arm randomized, double-blind, placebo-controlled trial was conducted in Tokyo, Japan. 60 healthy Japanese individuals aged 50-75 who were aware of their cognitive decline were randomly and equally divided into three groups of 20 participants using computer-generated random numbers. Participants took either MCW (equivalent to 60 μg/day of oleamide), 60 μg/day of oleamide, or placebo capsules for 12 weeks. Serum BDNF, cognitive function by Cognitrax as primary and MCI Screen as secondary outcome, and sleep status using the Japanese version of the Pittsburgh Sleep Quality Index (PSQI-J) were assessed before and after intervention. The participants, outcome assessors and analysts, and research assistants were blinded to the group assignment. Of the 60 participants, 58 completed the study and were analyzed. No adverse events related to test foods were observed. The placebo group showed a negative rate of change in serum BDNF (-10.5% ± 19.7%), whereas the MCW and oleamide groups showed positive changes (2.0% ± 27.1% and 1.3% ± 13.5%, respectively). Cognitrax scores increased after 12 weeks in all groups. Conversely, the MPI score of the MCI Screen demonstrated a significant improvement in the MCW and oleamide groups compared to the placebo group (p = 0.013 and p < 0.001, respectively). The subscales, immediate free recall and delayed free recall, also significantly increased in them compared to the placebo group. Although PSQI-J revealed no significant differences among groups, the MCW and oleamide groups showed significant improvement after intervention in overall score, subjective sleep quality, and sleep latency. Our results suggest that MCW and its component, oleamide, are safe and contribute to maintaining cognitive functions, particularly short-term and working memory, and improving sleep state. Clinical trial registration: https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000054792, identifier UMIN-CTR UMIN000048084.

Dairy Matrix Effects: Physicochemical Properties Underlying a Multifaceted Paradigm

When food products are often considered only as a source of individual nutrients or a collection of nutrients, this overlooks the importance of interactions between nutrients, but also interactions between nutrients and other constituents of food, i.e., the product matrix. This product matrix, which can be defined as 'The components of the product, their interactions, their structural organization within the product and the resultant physicochemical properties of the product', plays a critical role in determining important product properties, such as product stability, sensory properties and nutritional and health outcomes. Such matrix effects can be defined as 'the functional outcome of specific component(s) as part of a specific product matrix'. In this article, dairy matrix effects are reviewed, with particular emphasis on the nutrition and health impact of dairy products. Such matrix effects are critical in explaining many effects of milk and dairy products on human nutrition and health that cannot be explained solely based on nutrient composition. Examples hereof include the low glycemic responses of milk and dairy products, the positive impact on dental health, the controlled amino acid absorption and the absence of CVD risk despite the presence of saturated fatty acids. Particularly, the changes occurring in the stomach, including, e.g., coagulation of casein micelles and creaming of aggregated fat globules, play a critical role in determining the kinetics of nutrient release and absorption.

Fermented foods: Harnessing their potential to modulate the microbiota-gut-brain axis for mental health

Over the past two decades, whole food supplementation strategies have been leveraged to target mental health. In addition, there has been increasing attention on the ability of gut microbes, so called psychobiotics, to positively impact behaviour though the microbiota-gut-brain axis. Fermented foods offer themselves as a combined whole food microbiota modulating intervention. Indeed, they contain potentially beneficial microbes, microbial metabolites and other bioactives, which are being harnessed to target the microbiota-gut-brain axis for positive benefits. This review highlights the diverse nature of fermented foods in terms of the raw materials used and type of fermentation employed, and summarises their potential to shape composition of the gut microbiota, the gut to brain communication pathways including the immune system and, ultimately, modulate the microbiota-gut-brain axis. Throughout, we identify knowledge gaps and challenges faced in designing human studies for investigating the mental health-promoting potential of individual fermented foods or components thereof. Importantly, we also suggest solutions that can advance understanding of the therapeutic merit of fermented foods to modulate the microbiota-gut-brain axis.

Determination of volatile compounds in white brine cheese and ultrafiltered cheese during ripening and shelf-life using nano-adsorbent fibers

In this study, determination of aromatic compounds in cheese samples was performed by headspace solid-phase microextraction (HS-SPME) using a new adsorbent as a novel coated fiber in combination with a gas chromatography/mass spectrometry or flame ionization detector to evaluate the changes during ripening. Brine and ultrafiltrated (UF) cheese were sampled via HS-SPME and analyzed by gas chromatography/mass spectrometry. Polysulfone and mesoporous carbon nitride were used as two types of fibers for coating. The results showed that the pH had significant decreased during the 120 days for brine cheese (p < 0.001), and during the 90 days (p < 0.001) for UF cheese. Acidity was relatively stable during the ripening period for both cheeses (p > 0.05). Protein content decreased during the ripening period for both cheeses (p < 0.001). Moisture content also significantly decreased during the ripening period for both cheeses (p < 0.001). 74 compounds were identified in brine cheese and 27 major components in UF cheese. Fatty acids were the predominant components, followed by aldehydes (n: 17, 22.9%), alcohol (n; 12, 16.2%), ester (n: 11, 14.8%), alkane (n: 7, 9.4%), and ketone (n: 6, 8.1%) for white brine cheese, while for UF cheese fatty acid (n: 12, 44.4%) and aldehyde (n: 5, 18.5%), alcohol (n: 3, 11.1%), ketone (n: 3, 11.1%), ester (n: 2, 7.4%) and alkane (n: 1, 3.7%).

Identification of key aroma compounds and core functional microorganisms associated with aroma formation for Monascus-fermented cheese

This study aimed to analyze the key aroma compounds and core functional microorganisms of Monascus-fermented cheese (MC). 36 key aroma compounds were identified according to gas chromatograph-mass spectrometer (GC-MS), aroma extract dilution analysis (AEDA), and odor activity values (OAV) analysis. And internal standard curves were used to clarify the changes in their concentration of them during cheese ripening. Furthermore, High-throughput sequencing was used to investigate the composition and dynamic changes of bacteria and fungi in MC, respectively. Lactococcus lactis was found to be the dominant bacterium while Monascus was confirmed to be the dominant fungus. In addition, Pearson correlation analysis showed that Lactococcus lactis, Staphylococcus, Trichococcus, and Monascus were strongly associated with the 36 key aroma compounds (r > 0.80, p < 0.05). Finally, a metabolic network containing biosynthetic pathways of the key aroma compounds was constructed. This study provides deeper insights into the unique aroma of MC and the contribution of cheese microbiota.

Determination of the effects of proteolysis-based changes by adjunct lactobacilli on the bioactivity (ACE-inhibitory and antioxidant activities) of cheese: a model cheese study

Bioactive properties, proteolysis and microbiology of model cheeses with and without adjunct lactobacilli (Lactobacillus helveticus, Lactiplantibacillus plantarum, Lactobacillus bulgaricus and L. casei) were studied during 120 days of storage at 8 or 16 °C. Bioactive properties were observed in peptide fractions (< 3 kDa, 3-10 kDa, < 10 kDa) separated using ultrafiltration membranes. Antioxidant activity of these fractions was determined by radical scavenging assays as ABTS [2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)]. Angiotensin-converting enzyme-inhibitory (ACE-i) activity (% and IC50) and peptide profiles of 70% ethanol-soluble and -insoluble fractions were determined by RP-HPLC. Use of lactobacilli as an adjunct culture significantly changed the RP-HPLC peptide profiles of the cheeses; however, slight changes were observed in the patterns of urea-polyacrylamide gel electrophoresis. Fractions smaller than 3 kDa had higher ACE-i and antioxidant activities for all cheese samples. In conclusion, this study indicates that the addition of lactobacilli as an adjunct culture contributed to the formation of bioactive compounds in the model cheeses and also changed the proteolysis levels.

Enhancing date seed phenolic bioaccessibility in soft cheese through a dehydrated liposome delivery system and its effect on testosterone-induced benign prostatic hyperplasia in rats

Introduction

The consumption of dairy products, including soft cheese, has been associated with numerous health benefits due to their high nutritional value. However, the phenolic compounds bioaccessibility present in soft cheese is limited due to their poor solubility and stability during digestion. So, this study aimed to develop an innovative soft cheese enriched with date seed phenolic compounds (DSP) extracted ultrasonically and incorporated into homogeneous liposomes and study its attenuation effect on testosterone-induced benign prostatic hyperplasia (BPH) in rats.

Methods

Date seed phenolic compounds were extracted using 98 and 50% ethanol along with water as solvents, employing ultrasonication at 10, 20, and 30-min intervals. The primary and secondary DSP-liposomes were prepared and dehydrated. The particle size, zeta potential, encapsulation efficiency, and morphology were measured. Incorporating dehydrated liposomes (1-3% w/w) into soft cheese and their impact on BPH using male Sprague-Dawley rats was assessed. After inducing BPH, rats were fed a cheese diet with dehydrated DSP-liposomes. Over 8 weeks, parameters including nutrition parameters, prostate enlargement analysis, biochemical parameters, hormones level, oxidative stress, and cytokines were analyzed.

Results and Discussion

The results showed that ultrasound-assisted extraction effectively reduced the extraction time and 30 min extraction EtOH 50% was enough to extract high yield of phenolic compounds (558 mg GA/g) and flavonoids (55 mg qu/g) with high antioxidant activity (74%). The biological results indicate that prostate weight and prostate index% were diminished in the treatment groups (1 and 2) compared to the BPH control group. The high antioxidant content present in the DSP-liposomes acted as the catalyst for suppressing the responses of the inflammatory cytokines, inhibiting the anti-inflammatory IL-10 production, and suppressing the elevated levels of lipid peroxidation products compared to the BPH group.

Conclusion

The treatment group (2) supplemented with dehydrated secondary DSP-liposomes exhibited the most significant variance (p < 0.05) as opposed to the BPH group. Liposomal encapsulation was proved to be a feasible approach for administering DSP in soft cheese, thereby establishing new functional food category possessing prophylactic properties against the advancement of BPH in rats.

Does a pickle a day keep Alzheimer's away? Fermented food in Alzheimer's disease: A review

Fermented food is commonly viewed as healthy, mostly due to its probiotic and digestion-enhancing properties and recently it has been examined with regard to the development of new therapeutic and preventive measures for Alzheimer's disease. Fermented food has been shown to have anti-inflammatory and antioxidant properties and to alter the gut microbiota. However, the exact pathogenesis of Alzheimer's disease is still unknown and its connections to systemic inflammation and gut dysbiosis, as potential targets of fermented food, require further investigation. Therefore, to sum up the current knowledge, this article reviews recent research on the pathogenesis of Alzheimer's disease with emphasis on the role of the gut-brain axis and studies examining the use of fermented foods. The analysis of the fermented food research includes clinical and preclinical in vivo and in vitro studies. The fermented food studies have shown promising effects on amyloid-β metabolism, inflammation, and cognitive impairment in animals and humans. Fermented food has great potential in developing new approaches to Alzheimer's disease treatment.

An Overview of the Occurrence of Bioactive Peptides in Different Types of Cheeses

The search for improvements in quality of life has increasingly involved changes in the diet, especially the consumption of foods which, in addition to having good nutritional value, are characterized by offering health benefits. Among the molecules that trigger several beneficial responses are peptides, which are specific fragments of proteins known to produce positive effects on the human body. This review aimed to discuss the bioactive potential of peptides from cheeses. Studies show that the protein composition of some cheese varieties exhibits a potential for the release of bioactive peptides. The production of these peptides can be promoted by some technological procedures that affect the milk structure and constituents. The cheese maturation process stands out for producing bioactive peptides due to the action of enzymes produced by lactic acid bacteria. Thus, in addition to being proteins with high biological value due to their excellent amino acid profile, peptides from some types of cheeses are endowed with functional properties such as anti-hypertensive, antimicrobial, antioxidant, anticarcinogenic, opioid, and zinc-binding activities.

Is diet related to osteoarthritis? A univariable and multivariable Mendelian randomization study that investigates 45 dietary habits and osteoarthritis

Background

Diet is a safe intervention for many chronic diseases as a modifiable lifestyle. However, the potential causal effect of many dietary intake habits on the risk of osteoarthritis has not been fully understood. The purpose of this study was to reveal the potential causal relationship of 45 genetically predicted dietary intakes with osteoarthritis and its subtypes.

Methods

Data on 45 dietary intakes were obtained from the UK Biobank study of approximately 500,000 participants, and data on six osteoarthritis-related phenotypes were obtained from the Genetics of Osteoarthritis Consortium study of 826,690 participants. We performed univariable Mendelian randomization (MR), multivariable MR and linkage disequilibrium score regression (LDSC) analyses.

Results

In univariate analyses, 59 potential associations between diet and osteoarthritis were found. After false discovery rate (FDR) correction and sensitivity analyses, 23 reliable causal evidence were identified. In multivariate analyses, controlling separately for the effects of body mass index, total body bone mineral density, and smoking status, eight robust causal relationships remained: Muesli intake was negatively associated with knee osteoarthritis, spine osteoarthritis and total knee replacement. Dried fruit intake had a negative association with osteoarthritis of knee and total knee replacement. Eating cheese may reduce the risk of osteoarthritis in the knee and spine. And alcohol usually taken with meals was associated with a reduced risk of total knee replacement. LDSC analyses showed significant genetic correlations between all exposures and their corresponding outcomes, respectively, in these eight causal relationships.

Conclusion

Evidence of dietary effects on osteoarthritis is provided in our study, which has important implications for the prevention, management, and intervention of osteoarthritis in common sites through rational dietary modification.

Characterizations and effects of pectin-coated nanoliposome loaded with Gijavash (Froriepia subpinnata) extract on the physicochemical properties of cheese

In this study, pectin-coated nanoliposomes containing Gijavash extract were used to formulate cheese and evaluate its shelf life, physicochemical, and sensory aspects. The study used a central composite design with three independent variables to prepare the cheese. The results showed that the optimal particle size, zeta potential, encapsulation efficiency, and DPPH radical antioxidant activity were 201.22 nm, -29.33 mV, 61.87%, and 57.54%, respectively. Adding nanoliposomes with varying extract amounts improved pH and lowered acidity in fortified cheeses. Moisture and lipolysis indices also improved after applying nanoliposomes. Sensory evaluation revealed that sensory acceptance was highest in the cheese with 15% extract. The study suggests that adding pectin-coated nanoliposomes containing Gijavash extract to cheese formulations may create novel products and improve their physicochemical properties.

Natural diversity of lactococci in γ-aminobutyric acid (GABA) production and genetic and phenotypic determinants

BACKGROUND

γ-aminobutyric acid (GABA) is a bioactive compound produced by lactic acid bacteria (LAB). The diversity of GABA production in the Lactococcus genus is poorly understood. Genotypic and phenotypic approaches were therefore combined in this study to shed light on this diversity. A comparative genomic study was performed on the GAD-system genes (gadR, gadC and gadB) involved in GABA production in 36 lactococci including L. lactis and L. cremoris species. In addition, 132 Lactococcus strains were screened for GABA production in culture medium supplemented with 34 mM L-glutamic acid with or without NaCl (0.3 M).

RESULTS

Comparative analysis of the nucleotide sequence alignments revealed the same genetic organization of the GAD system in all strains except one, which has an insertion sequence element (IS981) into the PgadCB promoter. This analysis also highlighted several deletions including a 3-bp deletion specific to the cremoris species located in the PgadR promoter, and a second 39-bp deletion specific to L. cremoris strains with a cremoris phenotype. Phenotypic analysis revealed that GABA production varied widely, but it was higher in L. lactis species than in L. cremoris, with an exceptional GABA production of up to 14 and 24 mM in two L. lactis strains. Moreover, adding chloride increased GABA production in some L. cremoris and L. lactis strains by a factor of up to 16 and GAD activity correlated well with GABA production.

CONCLUSIONS

This genomic analysis unambiguously characterized the cremoris phenotype of L. cremoris species and modified GadB and GadR proteins explain why the corresponding strains do not produce GABA. Finally, we found that glutamate decarboxylase activity revealing GadB protein amount, varied widely between the strains and correlated well with GABA production both with and without chloride. As this protein level is associated to gene expression, the regulation of GAD gene expression was identified as a major contributor to this diversity.

Cooperative combination of non-targeted metabolomics and targeted taste analysis for elucidating the taste metabolite profile and pathways of traditional fermented golden pompano

Fermentation plays a key role in taste formation in traditional fermented golden pompano and involves a series of complex metabolic reactions. Indeed, the taste profile of fermented golden pompano exhibits remarkable variation during early fermentation. Herein, nutritional fingerprinting (proteins, amino acids, lipids, etc.) was applied to discriminate the various biomolecular changes involved in golden pompano fermentation. Among the differential metabolites, amino acids, small peptides, lipids, and nucleotides were considered taste-related compounds. An increase in the amino acid content was observed during fermentation, while the peptide content decreased. Glutamic acid, alanine, and lysine had the highest taste activity values and were the main contributors to taste formation. Metabolic pathway enrichment analysis revealed that taste formation was primarily associated with alanine, aspartate, and glutamate metabolism. These findings provide a deeper understanding of taste mechanisms and establish a basis for the targeted regulation of taste formation in the fermented fish industry.

Acceleration of proteolysis, flavour development and enhanced bioactivity in a model cheese using Kuflu cheese slurry: An optimisation study

This study aimed to use Kuflu (a mould-ripened cheese) cheese slurry to accelerate ripening, improve biological activity and flavour development in a model cheese in terms of proteolysis and volatile compounds. Response surface methodology (RSM) was employed for the model cheese to determine higher proteolysis and volatile development level during ripening as a function of Kuflu cheese slurry addition level (0-5 %), salt concentration (1-3 %) and ripening temperature (5-15 °C). The highest aminopeptidase activities (0.140 and 0.187 OD/g per hour) were determined in 15-day-old samples containing 3 % and 5 % Kuflu cheese slurry, respectively. Also, the use of Kuflu cheese slurry, regardless of ripening, caused an increase in ABTS^*+ antioxidants, angiotensin-converting enzyme (ACE)-inhibition activity and volatile compounds in model cheeses. The sensory evaluation indicated that the use of 3 % (w/w) Kuflu cheese slurry, storage temperature 10 °C for 15 days provided better flavour, odour, texture, colour, appearance and overall acceptability. In conclusion, using Kuflu cheese slurry for model cheese production enhanced the level of proteolysis and volatile flavour composition with shortened ripening time.

Linoleic acid enrichment of cheese by okara flour and Geotrichum candidum overexpressing Δ12 fatty acid desaturase

BACKGROUND

Mold-ripened cheeses have low levels of unsaturated fatty acids (UFAs). Geotrichum candidum is an adjunct culture for the development of Geotrichum-ripened cheese but has a low ability to produce high levels of UFAs. Δ12 fatty acid desaturase (FADS12) is a pivotal enzyme that converts oleic acid (OA) to linoleic acid (LA) and plays a vital role in UFA biosynthesis. By investigating FADS12 catalytic activity from various species with OA substrates, we found that FADS12 from Mucor circinelloides (McFADS12) had the highest catalytic activity for OA.

RESULTS

In the current study, a plasmid harboring McFADS12 was constructed and overexpressed in G. candidum. Our results showed that LA production increased to 31.1 ± 1.4% in engineered G. candidum - three times higher than that in wild-type G. candidum. To enhance LA production, an exogenous substrate (OA) was supplemented, and the yield of LA was increased to 154 ± 6 mg L^-1 in engineered G. candidum. Engineered G. candidum was used as an adjunct culture for Geotrichum-ripened cheese production. The LA level reached 74.3 ± 5.4 g kg^-1 cheese, whereas the level of saturated fatty acids (SFAs) decreased by 9.9 ± 0.5%. In addition, the soybean byproduct (okara) was introduced into the engineered G. candidum growth and the level of LA increased to 126 ± 4 g kg^-1 cheese and the percentage of UFAs:SFAs increased from 0.8:1 to 1.3:1.

CONCLUSION

This study offers a suitable technology for converting SFAs to UFAs in Geotrichum-ripened cheeses and provides a novel trend for converting soybean waste into a value-added product. © 2022 Society of Chemical Industry.

Evaluation of gamma-aminobutyric acid content in Portuguese cheeses with protected designation of origin status

Health-conscious consumers are increasingly paying attention to healthy diets and focusing on natural bioactive compounds in foods and their effects on mental health. This opens new opportunities for the study of artisanal cheeses as biofunctional foods. In the work described in this Research Communication, the gamma-aminobutyric acid (GABA) content of seven different Portuguese cheeses produced from unpasteurized cow, sheep, and goat milk and granted with protected designation of origin (PDO) status was analysed. The PDO cheeses made from cow milk analysed in this study were São Jorge (3, 4, 7, 12 and 24 months of maturation) and Pico cheeses. PDO cheeses made from sheep milk were Serra da Estrela, Serpa, Nisa and Azeitão. Cheeses made from sheep and goat milk included Beira Baixa yellow cheese. The GABA content in the Azorean PDO cheeses (made from cow milk) ranged from 1.23 to 2.64 g/kg of cheese. Higher variations in GABA content were observed in cheeses made from sheep and goat milk (0.73-2.31 g/kg). This study provides information on the GABA content in different Portuguese PDO cheeses and shows that hard or semi-hard ripened cheeses are a suitable matrix for GABA production by lactic acid bacteria.

Peptidomics Profile, Bioactive Peptides Identification and Biological Activities of Six Different Cheese Varieties

Several recent published studies reported that cheese consumption may protect against the onset of cardiovascular diseases and type-2 diabetes due to the presence of bioactive peptides. In the present work, six cheese varieties (the Egyptian traditional cheeses Karish, Domiati and Ras as well as Feta-type, Gouda and Edam cheeses) were characterized for their peptidomics profiles with high-resolution mass spectrometry, biological activities and content in bioactive peptides. The highest ACE-inhibitory and DPP-IV-inhibitory activities were found in Gouda cheese, which also displayed the highest antioxidant activity. A total of 809 peptides originating from the major milk proteins were identified, and 82 of them were bioactive. Most of them showed ACE-inhibitory, antioxidant and DPP-IV-inhibitory activities. The highest amount of the in vivo anti-hypertensive tripeptides VPP and IPP was found in Gouda cheese (39.19 ± 1.26 and 17.72 ± 0.89 mg/100 g of cheese, respectively), whereas the highest amount of APFPE was detected in Edam cheese (509.13 ± 20.44 mg/100 g of cheese). These results suggest that the intake of Edam, Domiati and, especially, Gouda cheeses may result in a possible anti-hypertensive effect in hypertensive subjects.

Antagonist action of Lactobacillus acidophilus against pathogenic strains in goat milk yogurt

Contamination by pathogenic bacteria is the major cause of foodborne diseases, which is an international public health issue. Probiotics added to fermented milk can fight against these pathogens. This research aimed to evaluate, by mathematical models, the behaviour of Lactobacillus acidophilus against pathogenic strains inoculated in goat milk yogurt. The Baranyi and Roberts' model was adjusted to data and statistically evaluated. A greater pathogens reduction occurred in the samples supplemented with probiotics, which exhibited antimicrobial activity against Pseudomonas aeruginosa. The reduction was less efficient against Escherichia coli. The primary models adjustment indicated that the Baranyi and Roberts fitted the reduction of P. aeruginosa, Salmonella typhimurium, E. coli and Staphylococcus aureus inactivation. The addition of L. acidophilus proved to be an effective alternative for the safer production of goat milk yogurt.

Influence of salt concentration on microbial growth in Kashkaval cheese

The aim of the present study was to evaluate the influence of NaCl concentration on the microflora in Kashkaval cheese produced from cow’s milk. Three cheese samples were obtained - with low (0.7%), medium (1.5%), and standard (3.1%) content of NaCl. Microbiological analyses were performed on the 1st, 15th, 30th, and 45th d of cheese ripening. It was established that the NaCl content has a significant (p < 0.05) influence on the growth and activity of the microflora in studied samples. It has been observed that the total Lactic acid bacteria (LAB) increased up to 30 d during ripening, after which their concentration decreased. A higher LABs count of samples with 0.7% NaCl and 1.5% NaCl in comparison with those containing 3.1% NaCl was found. At the same time, the variations in the salt content do not have a significant (p > 0.05) impact on the growth of Psychrotrophic bacteria, while in samples with a low salt content, the growth of Yeast and Molds was more intense. The data obtained in the present study showed that the concentration of NaCl is important for the regulation of activity of microbiological processes during the ripening of the Kashkaval cheese samples.

The Functional Characteristics of Goat Cheese Microbiota from a One-Health Perspective

Goat cheese is an important element of the Mediterranean diet, appreciated for its health-promoting features and unique taste. A pivotal role in the development of these characteristics is attributed to the microbiota and its continuous remodeling over space and time. Nevertheless, no thorough study of the cheese-associated microbiota using two metaomics approaches has previously been conducted. Here, we employed 16S rRNA gene sequencing and metaproteomics to explore the microbiota of a typical raw goat milk cheese at various ripening timepoints and depths of the cheese wheel. The 16S rRNA gene-sequencing and metaproteomics results described a stable microbiota ecology across the selected ripening timepoints, providing evidence for the microbiologically driven fermentation of goat milk products. The important features of the microbiota harbored on the surface and in the core of the cheese mass were highlighted in both compositional and functional terms. We observed the rind microbiota struggling to maintain the biosafety of the cheese through competition mechanisms and/or by preventing the colonization of the cheese by pathobionts of animal or environmental origin. The core microbiota was focused on other biochemical processes, supporting its role in the development of both the health benefits and the pleasant gustatory nuances of goat cheese.

Peptide profile of Parmigiano Reggiano cheese after simulated gastrointestinal digestion: From quality drivers to functional compounds

Time of ripening has a strong impact on shaping the valuable and recognizable characteristics of long-ripened types of cheese such as Parmigiano Reggiano (PR) due to the interrelationship between microbiota and proteolysis that occurs during ripening. The derived peptide profile is linked to cheese quality and represents the canvas for enzymes upon digestion, which could be responsible for the release of potentially bioactive peptides (BPs). In this study, we aimed at investigating the presence of BP in 72 PR cheese samples of different ripening times, from curd to 24 months of ripening, produced in six different dairies, and following their fate after simulated gastrointestinal digestion. A small number of peptide sequences sharing 100% similarity with known antimicrobial, antioxidant, and ACE-inhibitor sequences were found in PR cheeses, while a higher number of potential BPs were found after their simulated gastrointestinal digestion, in different amounts according to ripening time. Taking advantage of the complex organization of the sampling plan, we were able to follow the fate of peptides considered quality drivers during cheese ripening to their release as functional compounds upon digestion.

An integrated approach to the analysis of antioxidative peptides derived from Gouda cheese with a modified β-casein content

This study is the first to present an integrated approach involving in silico and in vitro protocols that was pursued to analyse an antioxidative potency of Gouda cheese with modified content of β-casein. Firstly, the predictions of the presence of antioxidant peptides in the casein sequences were computed using the BIOPEP-UWM database. Then, the antioxidative bioactivity of six variants of Gouda cheese (with reduced, normative, and increased content of β-casein at the initial and final stage of ripening) was assessed. Finally, the RP-HPLC–MS/MS was applied to identify antioxidative peptides in Gouda-derived water-soluble extracts (WSEs). Analyses were supported with the heatmaps and the computation of parameters describing the efficiency of proteolysis of caseins in the modified Gouda cheeses, i.e., the frequency and the relative frequency of the release of antioxidative fragments during cheese ripening (A_Eexp and W_exp., respectively). All Gouda cheese variants exhibited the antioxidative potential which differed depending on the assay employed. The highest antioxidative activity (ABTS^·+ radical scavenging effect, FRAP, and Fe-chelating) was observed for WSEs derived from Gouda cheese with increased content of β-casein after the 60th day of ripening. The results obtained suggest the potential of Gouda cheese as the antioxidant-promoting food.

The identification of antioxidant and ACE-I peptides in different turkish ripened cheeses

The principal purpose of this study was to determine antioxidant and ACE-inhibitory (angiotensin converting enzyme) activities of 5 ripened Turkish cheese varieties (Kashar, Erzincan Tulum, Izmir Tulum Gruyere, Mihalic). Among the water-soluble extracts with a molecular weight smaller than 3 kDa Gruyere and Erzincan Tulum exhibited the highest free radical scavenger activity in FRAP (Ferric Reducing Ability of Plasma) and ABTS [2,20-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid)] assays, respectively. For the inhibition of ACE, Mihalic was more effective than others. The water-soluble extracts of five cheese were analyzed with liquid chromatography-tandem mass spectrometry to identify the peptide sequences. Totally 394 peptides were sequenced; of these, 134 from αs1-casein, 44 from αs2-casein, 198 from β-casein, and 18 from κ-casein. Among these sequences, 48 peptides were reported as bioactive with the activities including ACE-inhibitory, antioxidant, antimicrobial, DPP-IV inhibitory, antidiabetic, immunomodulating, antithrombotic, anti-inflammatory, and inhibition of cholesterol solubility. These results showed that Turkish cheeses are good sources of bioactive peptides.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13197-022-05414-3.

Lactic Acid Bacteria in Raw-Milk Cheeses: From Starter Cultures to Probiotic Functions

Traditional cheeses produced from raw milk exhibit a complex microbiota, characterized by a sequence of different microorganisms from milk coagulation and throughout maturation. Lactic acid bacteria (LAB) play an essential role in traditional cheese making, either as starter cultures that cause the rapid acidification of milk or as secondary microbiota that play an important role during cheese ripening. The enzymes produced by such dynamic LAB communities in raw milk are crucial, since they support proteolysis and lipolysis as chief drivers of flavor and texture of cheese. Recently, several LAB species have been characterized and used as probiotics that successfully promote human health. This review highlights the latest trends encompassing LAB acting in traditional raw milk cheeses (from cow, sheep, and goat milk), and their potential as probiotics and producers of bioactive compounds with health-promoting effects.

Cynara cardunculus as a potential source of milk coagulating protease: Effects on physical properties of cow's milk

In the present research study, Cynara cardunculus (wild cardoon) flowers were blended and extracted using different types of buffers (phosphate buffer; citrate buffer and distilled water) for different maceration times. The most reliable, quick and efficient buffer was found to be phosphate (pH = 6.5) with a 6‐h maceration time, which was used throughout this study. C. cardunculus extract (CE) was found to have high clotting and proteolytic activities. The extracted enzyme was found to be very stable against a wide range of pH values as well as of temperature. The formation of milk gels prepared in the presence of CE with different types of milk was evaluated using dynamic rheology and Turbiscan. The evolution of both elastic (G′) and viscous (G″) moduli was monitored with time. The values of the whole milk enriched with milk powder gels were higher. Coagulum stability was evaluated using Turbiscan. The textural properties and the curd‐firming rate of coagulum were also determined. In conclusion, the prepared CE could be an efficient milk‐clotting agent in the production of dairy products.

Antioxidant capacity and identification of radical scavenging peptides from Crema de Chiapas, Fresco and Cocido cheeses

Bioactive peptides may positively impact bodily functions. One of these are the antioxidant peptides which are well documented for a wide variety of food matrices, mostly from plant sources. Nevertheless, information of antioxidant milk-derived peptides is still a little-known field. The present study was aimed to evaluating the antioxidant capacity (AC) in vitro of water soluble extracts < 3 kDa (WSE) from three artisanal Mexican cheeses: Crema de Chiapas (CrC), Fresco (FC) and Cocido (CC). This study was carried out for cheeses of different days of storage (0, 5, 10, 15, and 20) at 4 °C. AC was assayed to the respective WSE by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diamoniun salt (ABTS) and oxygen radical absorbance capacity (ORAC) methods and those WSE that showed the most antioxidant capacity from each cheese were analyzed by using RP-HPLC/MS to identify and characterize the novel specific peptides. All the WSE analyzed show antioxidant capacity, especially those from CrC and CC which display the highest AC at 15 days of storage. Regarding to WSE from FC, the AC was constant during storage. Identified structures reveal that these novel peptides possess high content of specific amino acids, mainly proline, valine, leucine and phenylalanine, of which it has already been shown antioxidant properties. This study demonstrate that these artisanal Mexican cheeses are sources of potential antioxidant peptides.

Fermented Foods and Their Role in Respiratory Health: A Mini-Review

Fermented foods (FFs) hold global attention because of their huge advantages. Their health benefits, palatability, preserved, tasteful, and aromatic properties impart potential importance in the comprehensive evaluation of FFs. The bioactive components, such as minerals, vitamins, fatty acids, amino acids, and other phytochemicals synthesized during fermentation, provide consumers with several health benefits. Fermentation of food is an ancient process that has met with many remarkable changes owing to the development of scientific technologies over the years. Initially, fermentation relied on back-slapping. Nowadays, starter cultures strains are specifically chosen for the type of fermentation process. Modern biotechnological methods are being implemented in the fermentation process to achieve the desired product in high quality. Respiratory and gastrointestinal tract infections are the most severe health issues affecting human beings of all age groups, especially children and older adults, during this COVID-19 pandemic period. Studies suggest that the consumption of probiotic Lactobacillus strains containing fermented foods protects the subjects from common infectious diseases (CIDs, which is classified as upper respiratory tract infections, lower respiratory tract infections and gastrointestinal infections) by improving the host’s immune system. Further studies are obligatory to develop probiotic-based functional FFs that are effective against CIDs. Presently, we are urged to find alternative, safe, and cost-effective prevention measures against CIDs. The current manuscript briefs the production of FFs, functional properties of FFs, and their beneficial effects against respiratory tract infections. It summarizes the outcomes of clinical trials using human subjects on the effects of supplementation of FFs.

Cow and Ewe Cheeses Made with Saffron: Characterization of Bioactive Compounds and Their Antiproliferative Effect in Cervical Adenocarcinoma (HeLa) and Breast Cancer (MDA-MB-231) Cells

Saffron is a widespread consumed spice containing many phytochemicals. It is often used in dairy technologies to enhance color and flavor of cheeses, but it is also known for its several therapeutic effects, as well as its antiproliferative and anticancer properties. In this study High Performance Liquid Chromatography was used to characterize saffron bioactive compounds in cow and ewe cheeses made with saffron, and the antiproliferative effect of the crocin-rich extracts from cheeses was investigated on different cellular lines (CaCo2, MDA-MB-231 and HeLa) by MTT assay. Crocins were observed in all cheese samples, with the total content ranging between 0.54 and 30.57 mg trans-4-GG/100 g cheese, according to the different cheese making process. Picrocrocin was detected in no cheese (probably due to its degradation during cheese making), while safranal was detected only in one ewe cheese (mainly due to its high volatility). HeLa and MDA-MB-231 cells were sensitive to treatment with crocin-rich extracts from cheeses, while no effect was observed on CaCo2 cells. The chemical environment of the food matrix seems to have a great influence on the crocin antiproliferative effect: the crocin-rich extracts from cheese with both high residual N/protein and fat contents showed increased antiproliferative effect compared to pure crocin (trans-4-GG), but cheeses from different milk species (type of fats and proteins) could also play an important role in modulating crocin’s antiproliferative effects.

Impact of an Omega-3-Enriched Sheep Diet on the Microbiota and Chemical Composition of Kefalograviera Cheese

Kefalograviera is a well-known hard Greek cheese. The aim of this study was to determine how milk produced from ewes fed omega-3-enriched diets could influence the microbiota as well as the chemical composition of Kefalograviera cheese. At the start of the trial, 30 dairy ewes (Lesvos and Chios crossbreed) were selected and fed a conventional diet, based on alfalfa hay, straw and concentrate feed that contained soybean meal for a period of thirty days. Then, for a period of sixty days the same ewes were fed an omega-3-enriched concentrate feed with a lower level of soybean meal that contained 10% flaxseed and 10% lupins. Milk yield was collected individually on Days 30, 60 and 90 and used to produce three different batches of Kefalograviera cheeses, at the same cheese factory, by using a traditional recipe and identical preparation conditions (pasteurization of milk, salt, rennet and culture). Sample analysis was done after six months of Kefalograviera cheese ripening. MALDI-TOF-MS (matrix-assisted laser desorption/ionization time of flight mass spectrometry) identification was performed by contrasting the samples’ mass spectra with the corresponding reference database. The correlation between the different Kefalograviera cheeses revealed the predominant species being Lactococcus lactis, Lactobacillus rhamnosus, Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus paracasei, Enterococcus faecium and Enterococcus faecalis, with significant quantitative differences between the experimental groups and the controls. Pediococcus spp. was isolated only from the experimental groups’ cheeses and Staphylococcus spp. only from the controls’ cheese, suggesting—among other differences—a bacterial microbiota distinction between the groups. Moreover, increased levels of alpha-linolenic acid and total polyunsaturated omega-3 fatty acids were noted in the enriched Kefalograviera cheeses. These promising findings suggest that enriched Kefalograviera cheese could be manufactured via enriching the ewes’ diets, with potential benefits for the consumers’ health.

Milk-clotting properties on bovine caseins of a novel cysteine peptidase from germinated Moringa oleifera seeds

A cysteine peptidase was previously identified from germinated Moringa oleifera seeds, but its milk-clotting properties on bovine caseins was still unclear. In this study, this novel cysteine peptidase (MoCP) showed preferential activity on κ-casein (κ-CN), with greater hydrolytic activity compared with calf rennet, whereas weak hydrolysis of α-casein and β-casein made MoCP suitable for application in cheesemaking and may yield various functional peptides. All 3 evaluated caseins were hydrolyzed to form relatively stable peptide bands within 3 h of proteolysis with MoCP. Cleavage sites were determined by gel electrophoresis, liquid chromatography mass spectrometry/mass spectrometry, and peptide sequencing, which revealed that cleavage of κ-CN by MoCP occurred at residue Ile129-Pro130 and generated a 14,895.37-Da peptide. The flocculation reaction between MoCP and κ-CN determined by 3-dimensional microscopy with super-depth of field revealed that the initial 30 min of reaction were key for milk coagulation, which may affect curd yield. Overall, the findings presented herein suggest that the cysteine peptidase from germinated M. oleifera seeds can be considered a promising plant-derived rennet alternative for use in cheese manufacture.

Serbian Traditional Goat Cheese: Physico-Chemical, Sensory, Hygienic and Safety Characteristics

This research project aimed to investigate the physico-chemical, sensory, hygienic and safety characteristics of raw goat milk, whey, brine and traditional goat cheese during the ripening period of 28 days. Physico-chemical parameters included the determination of dry matter, fat, ash, protein, pH, water activity and NaCl content. The presence of Enterobacteriaceae and fungi was estimated on milk and cheese samples, and a sensory panel evaluated the products' features and acceptability during ripening. The results show that the cheese under study belongs to the acid full-fat cheese group. A consumer panel attributed high scores to the goat cheese, until the 21st day of ripening. After this period, the overall features altered significantly, including augmented bitterness, odor intensification and the development of molds on the surface. The presence of fungi, associated with Enterobacteriaceae, suggests that the hygiene of the production processes needs to be improved. Regarding microbial safety, the detection of putative pathogens and antibiotic resistances recommend an active surveillance of traditional foods to avoid foodborne infections and/or the dissemination of resistant microorganisms along the food chain.

Sheep’s milk cheeses as a source of bioactive compounds

Since ancient times, sheep`s milk cheeses have been a part of a human diet. Currently, their consumption is of great interest due to its nutritional and health values. The aim of the article was to review the chemical composition of sheep’s milk cheeses and its main bioactive ingredients in the context of nutritional and health values. Sheep’s milk cheeses are rich in functionally and physiologically active compounds such as: vitamins, minerals, fatty acids, terpenes, sialic acid, orotic acid and L-carnitine, which are largely originate from milk. Fermentation and maturation process additionally enrich them in other bioactive substances as: bioactive peptides, γ-aminobutyric acid (GABA) or biogenic amines. Studies show that sheep’s milk cheese consumption may be helpful in the prevention of civilization diseases, i.e. hypertension, obesity or cancer. However, due to the presence of biogenic amines, people with metabolic disorders should be careful of their intake.

Eating Fermented: Health Benefits of LAB-Fermented Foods

Lactic acid bacteria (LAB) are involved in producing a considerable number of fermented products consumed worldwide. Many of those LAB fermented foods are recognized as beneficial for human health due to probiotic LAB or their metabolites produced during food fermentation or after food digestion. In this review, we aim to gather and discuss available information on the health-related effects of LAB-fermented foods. In particular, we focused on the most widely consumed LAB-fermented foods such as yoghurt, kefir, cheese, and plant-based products such as sauerkrauts and kimchi.