Fresh Cheese Research Articles

The Influence of Bioactive Compounds in Food Products

Demand for healthy and nutritious food is growing worldwide. The aim is to produce food products that not only satisfy the need for food but also provide many nutritional benefits to the health of the consumer. The current study aims to produce a food product with high nutritional value. For this purpose, a fresh cow's milk cheese was fortified with grape powder. The amount of powder added was different, with 3 samples plus a control sample in which no powder was added. The resulting products were sensory analysed to determine consumer acceptability. The samples were also analysed physico-chemically and enzymatically, measuring pH, lactose and lactic acid content over a storage period of 14 days. Fresh cow's cheese samples with added grape powder obtained superior results compared to the control sample during the whole storage period. The grape powder added to fresh cow's cheese positively influenced the sensory and enzymatic characteristics of the finished product.

Assessment of the Functional Potential of Two Autochthonous Lactic Strains of Lactobacilli Isolated from Algerian Dairy Products

Background: In cheese-making technology, lactic coagulation of milk is an essential stage in which the use of a ferment may be a selected strain or a mixture of strains that do not all have the same performance and technological properties, resulting in a wide variation in the quality of the cheese product. Methods: The aim of this study was to highlight the technological aptitudes of two strains of lactic acid bacteria, LAB, indigenous to our Algerian dairy products, Lactobacillus acidophilus and Lactobacillus brevis. The study monitored their growth kinetics, hydrogen ion concentration, fermentation profile and proteolytic activity on cheese milk. Result: Both strains gave good results, with very good growth kinetics, a good hydrogen ion concentration for cheese processing and an excellent proteolytic profile (proteolytic activity at 1, 2 and 3%). These 02 LAB revealed good technological performance in terms of cheese application, for lactic fermentation, lactic coagulation and also through their noted proteolytic activity can lead to good cheese maturation during ripening. This assessment leads us to conclude that these strains could be used for cheese applications in single or mixed cultures and with the possibility of being used in a cheese processing technology with lactic dominance for fresh cheeses or mixed enzymatic and lactic dominance for soft and pressed cheeses.

Cross-sectional, commercial testing, and chromatographic study of the occurrence of antibiotic residues throughout an artisanal raw milk cheese production chain

This study investigated antibiotic utilization in artisanal dairies and residue occurrence throughout the raw milk cheese production chain using commercial testing (Charm KIS and Eclipse Farm3G) and UHPLC-QqQ-MS/MS and LC-QqQ-MS/MS. The cross-sectional survey results revealed gaps in the producers’ knowledge of antibiotic use. Commercial testing detected antibiotic levels close to the LOD in 12.5 % of the samples, mainly in raw milk and whey, with 10.0 % testing positive, specifically in fresh and ripened cheeses, indicating that antibiotics are concentrated during cheese-making. Chromatographically, several antibiotics were identified in the faeces of healthy animals, with chlortetracycline (15.7 ± 34.5 µg/kg) and sulfamethazine (7.69 ± 16.5 µg/kg) predominating. However, only tylosin was identified in raw milk (3.28 ± 7.44 µg/kg) and whey (2.91 ± 6.55 µg/kg), and none were found in fresh or ripened cheeses. The discrepancy between commercial and analytical approaches is attributed to compounds or metabolites not covered chromatographically.

Produção de queijo fresco usando papaína liofilizada como coagulante vegetal

Abstract The study examined the efficacy of freeze-dried papain enzyme obtained from three Vasconcellea species (V. pubescens, V. chachapoyensis, V. heilbornii) as a natural coagulant in cheese making. Notably, the enzyme V. pubescens demonstrated the most promising results when concentrations of 2 g/L, 4 g/L, and 6 g/L were used to produce fresh cheese, while other enzyme species exhibited lower efficacy. The optimal yield of fresh cheese with minimal residual enzyme was achieved when a 2 g/L dose of papain enzyme was employed at a coagulation temperature of 30 °C, resulting in physicochemical and organoleptic characteristics comparable to those produced with commercial Hansen’s rennet. Nevertheless, an increase in the coagulation temperature (42 °C) and a higher dose of papain enzyme (4 g/L) resulted in a reduction in the yield of fresh cheese and; consequently, the residual enzyme increased. Further studies are required to determine the purity of freeze-dried papain and the most effective dosage to increase profitability for producers and consumers. Such findings could facilitate the ecological application of this alternative in producing of fresh cheese.

Design of prebiotic cheese spreads enriched with biologically active compounds

The development of functional foods providing health benefits above the basic nutritional needs is of growing interest to the food industry. This research aimed to: design fresh prebiotic cheese spreads enriched with agave inulin (AI), thyme (Thymus callieri Borbás ex Velen.) and hawthorn fruit (Crataegus monogyna Jacq.) as plant sources of biologically active compounds; observe the physicochemical and microbiological changes in the cheese during storage at 4°C for 35 days; evaluate the sensory characteristics of the new functional products. Therefore, five experimental groups of fresh cheese spreads were prepared – a control; 1% AI + 0.2% thyme; 2% AI + 0.2% thyme; 1% AI + 0.4% hawthorn fruit and 2% AI + 0.4% hawthorn fruit. During the storage, pH in all experimental groups gradually decreased (reaching values between 4.17 and 4.25 on the 35th day), which corresponded to the increasing titratable acidity (reaching values from 146.30°T to 152.51°T on the 35th day). The application of thyme and hawthorn fruit did not reduce the total plate count (mesophilic aerobic and facultative anaerobic microorganisms) and yeasts; however, during the storage period the addition of agave inulin stimulated the growth of lactic acid bacteria in the treated samples compared to the control.

Novel formulations for developing fresh hybrid cheese analogues utilizing fungal-fermented brewery side-stream flours

This study investigated the development of hybrid cheese analogues (HCA) made with fermented brewery side-stream ingredients (spent yeast and malt rootlets) and dairy milk. Different percentages of side-stream flours (3.5%, 5%, and 7.5%) were mixed with pasteurized milk, and the developed HCA were evaluated for their biochemical and textural properties. The addition of a fermentation step improved nutrient availability and led to pH (range 4.79–5.60) and moisture content (range 45.86%–61.29%) similar to traditional animal-based fresh cheeses (control). The inclusion of side-stream flours led to coagulation, even without rennet addition. The higher the concentration of the flour used, the faster the coagulation time, suggesting synergistic effect between the enzymes of the rennet and the enzymes present in the fermented side-stream flours. Nevertheless, textural properties were inferior compared to the control. Selected HCA formulations with added 3.5% flour exhibited increased counts of enterococci and enterobacteria cell densities, ranging from 7.28 ± 0.03 to 7.72 ± 0.09 log CFU/g and 4.90 ± 0.16 to 5.41 ± 0.01 log CFU/g, respectively. Compared to the control sample, HCA formulations exhibited higher concentrations of organic acids, peptides, and free amino acids (FAAs). Lactic acid reached up to 23.78 ± 0.94 g/kg of dry matter (DM), while the peptide area reached up to 22918.50 ± 2370.93 mL⋅AU. Additionally, the total concentration of individual FAAs reached up to 2809.74 ± 104.85 mg/kg of DM, contrasted with the control, which resulted in lower concentrations (847.65 ± 0.02 mg/kg of DM). The overall findings suggested that despite challenges in microbiological quality and textural properties, HCA produced with the inclusion of up to 3.5% brewery side-stream flours could be a sustainable solution to produce nutritious dairy alternatives.

Design of a Fresh Cheese Processing Plant: Optimizing Operational Efficiency and Biosafety in the Post-COVID Era

Design of a Fresh Cheese Processing Plant: Optimizing Operational Efficiency and Biosafety in the Post-COVID Era

Impact of Socioeconomic and Demographic Factors on the Physicochemical and Microbiological Quality of Artisanal Cheeses from Northern Peru

Goat cheese offers significant nutritional benefits due to its enhanced digestibility and assimilation. In Peru, the province of Sullana stands out as the largest producer of this cheese. However, there is limited knowledge regarding the socioeconomic factors of its producers, as well as the physicochemical and microbiological characteristics of the cheese. The study was developed in 3 aspects, socio-economic based on a descriptive exploratory methodology, with a mixed approach, 14 presidents of producer associations participated. Fourteen samples of fresh artisanal cheese from goat producers' associations from Marcavelica, Lancones and Salitral were stored at 4°C under aseptic conditions for physico-chemical characterisation and microbiological analysis. In relation to socioeconomic factors, the findings of the survey indicate that 42.9% were aged 56 years or older and possess only primary education. Additionally, 57.1% received Good Manufacturing Practices (GMP) training, 86% reported a lack of water and drainage services, 21% reported having access to conventional electricity and 79% reported using solar panels. These make an improvement in the training of cheese producers imperative. Regarding the physicochemical properties (pH, acidity, humidity and ash content), the cheeses were within the parameters allowed in DS N° 007-2021-MINAGRI. However, it was observed that 29% and 50% of the samples exhibited a high count for aerophilic mesophiles at 24 (≥ 2.51 x 106 CFU/g) and 48 (≥ 2.34 x 106 CFU/g) hours, respectively (COVENIN 3338:1997). 79% of the samples tested positive for both total and fecal coliforms (DS N° 007-2021-MINAGRI) in which 43% exhibited a high count for E. coli (>3.6 MPN/g). Conversely, the presence of S. aureus (<10) was within the optimal parameters while Salmonella spp. and L. monocytogenes were not detected. The lack of adequate infrastructure for the milking process, the production, storage and transportation of cheese, is presented as the most significant aspect. These findings may pose a risk to consumers’ health, highlighting the necessity to establish projects that strengthen these aspects in order to enhance cheese production.

Utilization of Partially Purified Milk Clotting Protease from Ginger Rhizome in the Manufacturing of Fresh Cheese

This study was carried out to utilize the partially purified ginger rhizome protease in fresh cheesemaking. The crude ginger rhizome extract was partially purified by employing 30-80% (NH4)2SO4 saturations (w/v). The maximum milk clotting activity was achieved at 50% saturation, exhibiting the purification fold of 1.64 and activity recovery of 85.76%. The milk pH and temperature for optimum time of coagulation and milk clotting activity were optimized by using response surface methodology (RSM). A numerical optimization study revealed that the optimum milk pH and temperature for producing cheese were 6.5 and 50 C respectively. The cheese produced by ginger protease had significantly (p<0.05) higher moisture, ash and yield, but lower fat content than the rennet cheese. No significant difference (p>0.05) was found in the calcium and protein content of both cheeses. The prepared cheese using ginger protease had significantly (p<0.05) higher spreadability, but lower aftertaste than the rennet cheese. However, non-significant difference (p>0.05) was observed in the flavor and overall acceptance between the two cheeses. Hence, this study demonstrated that the ginger rhizome protease has the potential to be utilized as an effective milk coagulating enzyme in the manufacturing of fresh cheese.

Harnessing the potential of chestnut shell extract to enhance fresh cheese: a sustainable approach for nutritional enrichment and shelf-life extension

A novel approach for enhancing the nutritional benefits and shelf-life of fresh cheese, while reducing food industry waste, is adding chestnut shell extract to the cheese. Chestnut shells are a great source of bioactive substances including phenolic compounds, with anti-inflammatory, antibacterial, and antioxidant activities. The chestnut shell extract exhibited interesting antioxidant properties, resulting from the presence of catechin and gallic acid, 2.59 and 0.97 mgcompound∙gsample−1, respectively, in its composition. The incorporation of the phenolic extract did not influence the pH value of the cheese, with values within the range of 6.2–6.5. Additionally, the extract decreased the syneresis which is important in terms of stability. Regarding the antioxidant characteristics, incorporating the extract improved this biological property. The results proved that an increase in the extract concentration allows the inhibition of higher percentages of this radical. Cheese with extract exhibited higher acceptance, but visual components need improvement. Hence, incorporating chestnut shell extract into fresh cheese is a promising approach to adding value to dairy products and promoting sustainable food production. This study can be considered innovative and relevant because it allows the utilisation of agro-industrial by-products to increase the shelf life of fresh cheese, an extremely relevant parameter for the producer, promoting the circular economy.

Brucellar Epididymo-Orchitis in a Brucellosis Hyperendemic Region in Türkiye.

Brucellosis is one of the most prevalent zoonoses worldwide and is endemic in Türkiye. It is a multisystemic infection that can affect various organ systems. Epididymo-orchitis is the most common form of genitourinary involvement. This study aimed to evaluate the incidence, clinical characteristics, laboratory values, and treatment outcomes of brucellar epididymo-orchitis (BEO) in the East Anatolian region, where brucellosis is hyperendemic. This study was conducted between January 1, 2018, and April 30, 2019. All male patients diagnosed with brucellosis at the infectious disease clinic were evaluated for epididymo-orchitis according to clinical findings (testicular pain, swelling, erythema). In addition, to identify BEO patients, all epididymo-orchitis cases admitted to the urology outpatient clinic according to the study protocol were referred to the infectious diseases clinic for Brucella infection. Patients were enrolled prospectively, and data were analyzed retrospectively. Brucella infection was diagnosed in 326 patients during the study period, of whom 208 (63.8%) were male. Brucellar epididymo-orchitis was diagnosed in 18 patients at the end of sixteen months. The incidence of epididymo-orchitis in patients with Brucella infection was 8.7%. The mean age of the patients was 36.9±11.5 years. The majority of patients had occupational animal contact (83.3%) and consumption of fresh cheese made from raw milk (55.5%). Acute brucellosis was diagnosed in 17 (94.4%) patients; all patients presented with scrotal pain and swelling. Unilateral epididymo-orchitis was observed in 16 (88.8%) patients. Most patients (88.3%) applied to outpatient clinics other than infectious diseases, especially the urology clinic (77.7%).Double or triple combined treatments with aminoglycoside/doxycycline/rifampicin were given to the patients. Hydrocelectomy was performed in three patients, orchiectomy in one patient, and relapse was seen in one patient. Brucella infection should be considered in patients presenting with epididymo-orchitis in endemic regions. Awareness of brucellosis by urologists will ensure that the disease is diagnosed without complications.

Influence of Somatic Cell Removal on Milk Quality and Yield

This investigation aimed to assess how the somatic cell count (SCC) impacts milk production and the physicochemical quality of milk, including the effects of centrifugation and microfiltration on SCCs and the yield of fresh cheese. Milk production was analysed at different somatic cell counts (SCCs) to observe how centrifugation and microfiltration affected the removal of SCs from the milk and the yield of fresh cheese. Tukey’s test was employed at a 5% significance level to compare the chemical composition of the milk, milk production, and fresh cheese yield when using microfiltered and/or centrifuged milk. Milk with an SCC of ≤200,000 somatic cells (SCs) per mL exhibited higher yields. Although centrifugation and microfiltration influenced milk fat content, total dry extract and SCC, they did not impact fresh cheese yield. It is important to note that these processes reduced the fat content and SCC, making skim milk a potential option for future research studies.

THE STUDY ON THE MANUFACTURE OF GOAT CHEESE IN THE SOUTH OF OLTENIA

The acidity of milk in batch I was the best of 18.66°T, in batches II and III the acidity had higher values ​​compared to the first batch and with the maximum requirements in force. The fat content in all the lots examined was satisfactory, having values ​​higher by 1.23 - 1.33% compared to the minimum requirements in force. In the examined batches, the protein content was in batch II of 3.5% or the minimum level according to the requirements in force and slightly higher in batch I - 3.66% and batch III - 3.67%. Among the components of milk, casein it is the component that ensures its coagulation under the action of enzymes. The casein content was the highest in batch III of 3.23%, followed by batch I - 2.97% and batch II - 2.73%. According to the requirements in force, the acidity of fresh goat cheese must not be higher than 40°T. The goat cheese from batch I falls within the requirements in force, while the goat cheese from batches II and III was obtained with a higher acidity than the requirements in force by 2.3°T, therefore it is more acidic. Comparing the data obtained with the requirements in force for goat cheese, we can mention that the water content of the cheese obtained by us was higher in all batches compared to the requirements in force (50%)

Cows’ and buffalo milk for cooked fresh cheese: preliminary comparison of the cheese-making efficiency and quality of griddled acid/heat-coagulated Paneer and rennet-coagulated Tosella/Schiz

Milk from cows and buffaloes represents the major source of dairy products worldwide. Cheese is consumed fresh, ripened, cooked, or as recipe ingredient in many different types. Using Paneer and Tosella/Schiz model cheeses as a case study of cooked cheeses, in this short communication we evaluated the cheese yield and quality of fresh cheese before and after cooking comparing the two major dairy species (cows and buffaloes). A total of 75 model cheeses (37 Paneer and 38 Tosella/Schiz) were made. Slices of all the cheeses were cooked on a griddle at 130 °C. Milk, whey, and cheese composition traits, cheese-making efficiency traits, and cooked cheese quality traits were evaluated using a mixed model that included the fixed effects of cheese type and animal species, and their interaction, and the random effects of session, animal within species, and the residual. Higher cheese yields are obtained from the buffalo milk not only because more concentrated in nutrients, but also for the greater recovery of nutrients in cheese. There was a greater recovery of protein with the acid/heat Paneer procedure than the rennet Tosella/Schiz procedure, but we found a species × cheese type interaction for fresh cheese yield. The interaction was related mainly to the higher water retained in the Tosella/Schiz curd rather than to total solids. This led also to greater cooking weight-loss compared with Paneer. The qualitative traits of cheese were highly affected by griddling. Future research on the sensorial perception of cooked cheeses from the two major dairy species is needed to predict consumer response.

Listeria monocytogenes, a silent foodborne pathogen in Ecuador.

Listeria monocytogenes is a foodborne pathogen that can produce serious, even fatal, infections. Among other foods, it can be found in unpasteurized dairy and ready-to-eat products. Surveillance of L. monocytogenes is of great interest since sources of infection are difficult to determine due to the long incubation period, and because the symptoms of listeriosis are similar to other diseases. We performed a genomic study of L. monocytogenes isolated from fresh cheeses and clinical samples from Ecuador. Sixty-five isolates were evaluated and sequenced, 14 isolates from cheese samples and 20 from clinical listeriosis cases from the National Institute of National Institute of Public Health Research, and 31 isolates from artisanal cheese samples from 8 provinces. All isolates exhibited heterogeneous patterns of the presence of pathogenicity islands. All isolates exhibited at least 4 genes from LIPI-1, but all references (26 L. monocytogenes closed genomes available in the NCBI database) showed the complete island, which encompasses 5 genes but is present in only two Ecuadorian isolates. Most isolates lacked gene actA. Genes from LIPI-2 were absent in all isolates. LIPI-3 and LIPI-4 were present in only a few references and isolates. With respect to the stress survival islets, our samples either presented SSI-1 or SSI-F2365, except for one isolate that presented SSI-F2365 and also one gene from SSI-1. None of the samples presented SSI-2. The predominant ST (sequence type) was ST2 (84.62% 55/65), and the only ST found in food (93.33% 42/45) and clinical samples (65% 13/20). Isolates were not grouped according to their sampling origin, date, or place in a phylogenetic tree obtained from the core alignment. The presence of ST2 in food and clinical samples, with high genomic similarity, suggests a foodborne infection risk linked to the consumption of fresh cheeses in Ecuador.

Enterotoxigenic and Antimicrobic Susceptibility Profile of Staphylococcus aureus Isolates from Fresh Cheese in Croatia.

Certain Staphylococcus aureus strains harbour staphylococcal enterotoxin genes and hence can produce enterotoxin during their growth in food. Therefore, food can be a source of staphylococcal food poisoning, one of the most common food-borne diseases worldwide. Epidemiological data show that S. aureus is often present in raw milk cheeses, and consequently, cheeses are often the source of staphylococcal food poisoning outbreaks. The aim of this study was to determine the phenotypic characteristics of S. aureus isolates from fresh cheese, including antibiotic susceptibility; the presence of classical sea-see enterotoxin genes through molecular methods; and the isolate's ability to produce SEA-SEE enterotoxins in vitro through reversed passive latex agglutination. A total of 180 coagulase-positive staphylococci were isolated from 18 out of 30 cheese samples, and 175 were confirmed as S. aureus through latex agglutination and API STAPH tests. All isolates possessed phenotypic characteristics typical for S. aureus, with certain variations in the egg yolk reaction (18.3% of the isolates showed a weak reaction and 28% no reaction at all) and haemolysis pattern (36.6% of the isolates produced double-haemolysis and 4.6% were non-haemolytic). Antibiotic resistance was observed in 1.1% of the isolates and to mupirocin only. Real-time PCR detected the sec gene in 34 (19.4%) isolates, but most isolates (80.6%) were not enterotoxigenic. For all 34 (19.4%) strains that carried the sec gene, the RPLA method detected the production of the SEC enterotoxin in vitro. For those enterotoxigenic strains, the possibility of enterotoxin production in fresh cheese could not be ruled out.

ANALYTICAL STUDY TO DETERMINE THE USE OF ANIMAL RENNET IN THE MANUFACTURE OF ANCIENT EGYPTIAN FOSSIL CHEESE

The recently discovered fossil cheese was carefully analyzed under the current study by using multiple analyzes such as, digital microscopy assessment, FTIR, XRD & SEM in a serious attempt to discover dairy products of Ancient Egyptians furthermore; knowing the type of rennet that was used to coagulate the milk, is it vegetable or animal? To make the results more accurate, fresh cheese samples were prepared from the pastures of the rich Saqqara region according to the old inherited recipes to make a revealing comparison with the archaeological sample then the fresh sample was subjected to accelerated heat- light ageing;the results revealed a striking similarity between the archaeological and the aged fresh cheese where the digital microscope revealed that both samples have the same structure but archeological sample was more fossilized which may be attributed to the survival of Ptahmes's cheese for thousands of years under the burning sands. It should be noted that the analysis of the infrared spectrum revealed accurate and important information about the technology of dairy products in the ancient Egyptians, especially that the authors compared the Ptahmes sample with the aged modern sample and a dried calf rennet sample, to prove or deny the Egyptian's use of calf rennet to coagulate milk, and it was a resounding surprise a presence of a band associated with N-H stretching vibration and hydrogen bands presented in collagen were detected which suggests the existence of helical arrangements of chymosin -solubilized collagen from casein furthermore a matching between the archaeological sample and the dried rennet in the region from 2000 to 4000 cm-¹ was detected which suggests using the calf rennet in curdling of milk in the ancient Egyptian civilization, the infrared spectraalso confirmed a presence of crystalline residues of fenugreek and red pepper, which are still used until now in storing cheese in upper Egypt.

Preparation and evaluation of goat cream cheese analogue for phenylketonuria

The primary treatment for individuals with phenylketonuria (PKU) is a lifetime diet with low phenylalanine (Phe) to achieve neurological health. The objective of this study was to make a highly nutritious and palatable low‐Phe cream cheese analogue based on the partial replacement of fresh goat cream cheese with two levels of glycomacropeptide (GMP; 7 or 10%), GUM (0.6 or 0.8), nondairy creamer (0.5 or 2%) and whey protein concentrate (WPC; 0 or 2%). The chemical composition, texture, viscosity, protein digestibility and sensory attributes of the resulting cheeses were evaluated. Incorporation of the GMP at different levels significantly changed the chemical properties of the cheese. With increased levels of GMP and GUM, viscosity and firmness significantly increased as the protein–protein and protein–gum interaction produced stronger gels in comparison with the systems containing nondairy creamer and WPC due to their inactive filler, whereas adhesiveness decreased. Sensory characteristics of cheese indicated that formula made with high concentration of variables seems to be superior for PKU patients, which contained 12.44 mg Phe per gram of protein, and 82.4% protein digestibility after 6 h of enzymatic hydrolysis. According to the results, the method used in this study can be employed in achieving cream cheese analogue with reduced Phe content, appropriate for PKU patients.

The biopreservative properties of Metschnikowia pulcherrima LMA 2038 and Trichosporon asahii LMA 810 in a model fresh cheese, are presented

The diversity of microorganisms present in cheeses contributes to their typicity and organoleptic properties. Inhibitory strains found in these ecosystems could be used as biopreservative agents in order to replace chemicals, which are increasingly decried by consumers. Here, we isolated from cheese two yeasts named, Metschnikowia pulcherrima LMA 2038 and Trichosporon asahii LMA 810, which are active against fungi, such as Yarrowia lipolytica LMA 800, Rhodotorula mucilaginosa LMA 808, Cladosporium cladosporioides LMA 31, and Penicillium commune LMA 72, as well as against bacteria, such as Listeria innocua ATCC 33090 and Clostridium tyrobutyricum LMG 1285. When cultivated on model fresh cheese, these antagonistic yeasts significantly reduced the number of Y. lipolytica LMA 800 and R. mucilaginosa LMA 808. Preliminary data enabled us to establish a snapshot of the molecules responsible for these antifungal and antibacterial inhibitions. The molecules presumed to be present in the culture supernatant were subjected to various treatments, including heat, pH variations and enzymatic treatments. Thus, we hypothesize that different antimicrobial compounds were produced by the aforementioned antagonistic yeasts, and these molecules act in a target strain-specific manner. In summary, our findings demonstrate that cheeses possess an innumerable supply of antagonistic microbial strains, which can be exploited in the field of biopreservation to substitute chemicals and extend the shell-life of food products, including cheese.

Profile of lactic acid bacteria (MALDI-TOF-MS) and physico-chemical and microbiological characteristics of the raw milk and fresh artisanal cheese from Serra Geral, Minas Gerais, Brazil

Artisanal cheese from Serra Geral, Minas Gerais, Brazil, stands out for its cultural asset and socio-economic relevance. However, standards of identity and quality and the peculiar terroir associated with the edaphoclimatic conditions have not been established. Therefore, the production flow diagram and the physico-chemical and microbiological quality of the raw milk, pingo (natural starter culture), production benches, water and fresh cheese were investigated for the first time. In addition, lactic acid bacteria (LAB) from cheese and its production environment were identified by MALDI-TOF. For that, 12 cheese making facilities were selected. The raw milk and pingo showed adequate physico-chemical characteristics for cheesemaking; however, high microbial counts were found. In the water, total and thermotolerant coliforms were also identified. The fresh cheeses were classified as ‘high moisture and fat’ and ‘soft mass’. Most physico-chemical parameters were satisfactory; however, there were high counts of total coliforms, Staphylococcus spp. and coagulase-positive staphylococci. There were high counts of LAB in the raw milk, pingo, bench surface and fresh cheese. A total of 84 microbial biotypes from MRS agar were isolated. Lactococcus lactis was the predominant LAB, followed by Lactococcus garvieae. Leuconostoc mesenteroides (benches), Leuconostoc pseudomesenteroides (fresh cheese), and Enterococcus faecium (pingo) were identified sporadically. These results indicate the risks to public health associated with the consumption of the fresh cheese, and measures to improve its safety are needed.