Traditional Cheese Research Articles

Effect of vegetable coagulant and lamb rennet on physicochemical composition, fatty acid profile and lipid quality indices of a traditional fresh cheese (Jben)

Jben is a popular traditional cheese in Algeria and North Africa, usually made from raw ruminant's milk, especially cow. Artisanal production methods are still used in many regions, especially during the abundant milk production season. This study aimed to evaluate and compare the effect of various coagulants (of animal and plant origin) on physicochemical parameters, fatty acids (FAs) profile and lipid quality indices in the traditional fresh cheese "Jben". These parameters were analyzed in Jben samples made with vegetable rennet (CVR) from Cynara cardunculus, which were compared with Jben cheeses made using lamb rennet (CLR). The physicochemical characterization showed that pH, titratable acidity, dry matter, fat, and protein contents were 6.19, 92.5 °D, 43.7 g/100 g, 23.4 g/100 g and 15.2 g/100 g cheese, respectively for CVR; and 5.21, 80.3 °D, 50.1 g/100 g, 20.6 g/100 g and 13.8 g/100 g cheese, respectively for CLR. The FAs composition was determined using gas chromatography-mass spectrometry (GC-MS) method. For CLR, FAs comprised 0.09–28.8% saturated fatty acids (SFAs), 0.85–27.68% monounsaturated fatty acids (MUFAs), and 3.22% of polyunsaturated fatty acids (PUFAs); whereas FAs of CVR included 0.22–27.81% SFAs, 1.10–28.16% MUFAs, and 3.07% PUFAs. The predominant FAs identified in all cheeses were C16:0, C18:0 and C18:1(9), with 28.80%, 13.37%, and 27.68% of total FAs, respectively for CLR, and 27.81%, 13.07%, and 28.16%, respectively for CVR. The lowest level of SFAs was observed in CVR, which had the most beneficial health indices with atherogenicity index (2.19), thrombogenicity index (2.91), desirable fatty acid ratio (49.40%) and high hypocholesterolemic/hypercholesterolemic fatty acid ratio (0.72).

Multi-mycotoxin production of cheese-derived fungal strains in vitro and in cheese models

With regards to the cheese industry, fungal growth is a widespread problem and usually producers make effort to avoid fungal development due to mycotoxin formation which adversely affects human health, reduces product quality, and causes economic losses. However, some fungal strains are also used as secondary cultures to obtain developed sensory properties in cheese as a result of the enzymatic activities of these strains. Non-commercial strains isolated from mould-ripened cheeses and/or autochthonous strains that spontaneously grown on cheese have much greater effect on the acquisition of appreciated sensory and textural characteristics in cheese. Autochthon strains particularly ensure a characteristic aroma of traditional cheeses that are not commercially produced and can be a potential adjunct providing not produce mycotoxins. In this study, 14 different Penicillium species previously isolated from traditional mould-ripened cheeses in cave were investigated for their mycotoxin production in both in vitro culture medium and in situ in cheese model. The results revealed that although individual strains produced various and higher amounts of mycotoxins in the culture medium, the number of produced mycotoxins and the obtained values were determined quite low in the cheese medium. The outcomes of this study highlight the mycotoxin production of strains depends on the composition and structure of the food matrix that they integrated and many different factors, such as presence of free fatty acids, antimicrobial and antifungal compounds of lactic acid bacteria, lack of carbohydrate sources, and sulfhydryl-containing compounds, such as cysteine and glutathione. Therefore, the method used in this study has a potential to be a new solution in the industry to produce mould-ripened cheeses under controlled conditions without any potential health risk.

The Effect of Phycocyanin on the Microbial, Antioxidant, and Nutritional Properties of Iranian Cheese

The prevailing conditions for the production, storage, and sale of traditional cheese seem to increase the probability of microbial contamination. <i>Escherichia coli</i> and <i>Staphylococcus aureus</i> are among the bacteria that may cause major complications such as diarrhea, hemolytic uremic syndrome (HUS), food poisoning, and gastrointestinal infections in cheese consumers. The use of food coloring to enhance the microbial load of food products, as an innovative and cost-effective biological control, is one of the most efficient methods in managing the production, storage, and quality of food. Extracted naturally from <i>Spirulina</i> sp., phycocyanin is widely used in various pharmaceutical, food, cosmetic and health industries. This is the first attempt to investigate the possible effect of adding phycocyanin pigment into traditional cheese, in order to improve-the nutritional value, quality and shelf life of traditional cheese. This study collected five different types of traditional cheese from different localities in Iran. The researcher immersed the samples in concentrations of 1%, 1.5% and 2% phycocyanin pigment. After identifying the existing bacteria, the possible effect of the pigment on the total number of bacteria, as well as the number of<i> E. coli</i> and <i>S. aureus</i>, were evaluated within 15 days. The study used Ferric ion reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and nitric oxide trapping with the sensory testing in order to determine the amount of protein, fat, ash, moisture, and antioxidant properties. Statistical analyses showed that, compared to the control group, the concentration of phycocyanin rose when the number of bacteria decreased and antioxidant activity increased in all types of cheese. The results revealed a significant increase in the amount of protein (93%), fat (80%), moisture (100%), and ash (67%). In addition, the highest consumer satisfaction was observed on day 1 and days 7 and 15; cheese with a concentrations of 1.5% and 2% pigments were preferred.

Identification and Technological Characterisation of Lactic Acid Bacteria Iso-lated From Traditional Algerian Cheese “J ben”

Lactic acid bacteria have long been utilized in fermented foods and dairy products such as cheese, these bacteria play an important role in food bio-preservation, organoleptic properties development, and quality improvement. The purpose of this research was to determine and assess the biotechnological characteristics of lactic acid bacteria isolated from traditional Algerian cheese "J'ben". Fifteen lactic acid bacteria (gram positive, catalase negative) were molecularly identified according to their 16S rDNA sequences, six belonged to Enterococcus durans, three to Enterococcus faecium, three to Lactococcus lactis, and three to Leuconostoc mesenteroide. The strains were evaluated for proteolysis, lipolysis, antibacterial activity, exopolysaccharide synthesis, and safety (hemolytic activity). All studied strains had considerable proteolytic activity but no lipolysis potential, they were also all γ-hemolytic. The antimicrobial activity of the stains against three pathogenic bacteria (Staphylococcus warneri, Serratia plymuthica, and Enterobacter aerogenes) revealed that they were active against at least one of them. Finally, only three organisms produced exopolysaccharide in our study Enterococcus durans (KC1); Leuconos-toc mesenteroide (KC6); and Lactococcus lactis (KC15). These findings suggest that the lactic acid bacteria isolated from traditional cheese "J'ben" have significant technological propereties, making them suitable for use as starter culture in fermented dairy products.

Determination and evaluation of whey protein content in matured cheese via liquid chromatography

To date, there is no valid analytical method available to determine the total whey protein (TWP) content in cheese. Therefore, the aim of this study was to develop HPLC methods for whey protein determination in mature cheese. For that purpose, foil-ripened whey protein-enriched model cheese and traditional Edam-type cheese were produced and analyzed. Suitable protein extraction methods and subsequent analytical methods to determine the acid-soluble whey protein (ASWP) and TWP content in cheese were developed. To characterize the influence of proteolysis on native and denatured whey proteins, the ASWP and TWP contents were determined throughout the ripening process. Both chromatographic methods showed that the individual whey proteins (α-lactalbumin and β-lactoglobulin) were not degraded during ripening. However, the analyzed ASWP content increased by up to 25% throughout ripening. Compared to traditional Edam-type cheese, the β-lactoglobulin content in whey protein-enriched cheese (containing 30% high-heat milk) increased by a factor of 3.5. To evaluate the chromatographic results, two different calculation models were used to estimate a reference value for the TWP content in the manufactured cheese. Further studies are required to optimize the quantification of TWP content in hard, semihard, soft, and cream cheeses.

Microbial and Physicochemical Quality of Kurdish Soft Cheese in Retail Markets in Erbil

Dairy products is considered the most complete foodstuff that provide human with most of their vital needs. The aim of this study to evaluate some chemical parameters and bacteriological quality of traditional white soft cheese. Our finding indicates that, the pH ranged between 5.72 to 7.25 with an average of 6.53, moisture percentage ranged between 37.76 % to 54.95 % with an average of 45.03%, fat percentage between 1.2 % to 4.3 % with an average of 2.36 %, protein percentage ranged between 16.3 % to 23.16 % with an average of 19.55 %. Ash percentage ranged between 1.7% to 2.8% with an average of 2.20. Total solid percentage ranged between 25 % to 37.7 %with an average of 31.26 %. Acidity ranged between 1.3 % to 2.5 % with an average of 1.70 %. Salt percentage ranged between 1.4 to 4.3 with an average of 2.89 %. The standard plate count of soft cheese was detected to be the interval of 1.2 x 104 - 4.7 x106 cfu/g. In the all cheese samples the coliform bacteria count was detected to be between 4.0 x103 to 8.6 x105 cfu/g. The yeast and mold count was found to be 9.6 x10 to 3.2 x105 cfu/g. The results found 20 % of Staphylococcus aureus contaminations, 13.33 % of Salmonella spp. contaminations. Cheese produced in Erbil are not agree with the Iraqi Standard.

Antimicrobial Edible Cellulose-Based (CB) Films and Coatings for Enhancing Microbial Safety of White Cheese During Storage

In this research, the antioxidant and antibacterial characteristics of edible cellulose-based film (CBEF) coating incorporated with β-carotene, Hesperedin and Propolis on the quality of the white cheese at 4°C were investigated. Samples evaluated were: Control, CBE films with 8 different contents containing natural or non-natural antimicrobial agents for 15 days at 5 day intervals. The antimicrobial effects of edible cellulosic films prepared with antimicrobial agents against Staphylococcus aureus and Escherichia coli, which are important food pathogens, were directly evaluated with artificially contaminated food samples under cold storage conditions. Fresh white cheese samples, which are one of the semi-hard traditional Turkish cheeses, were used for artificial contamination. The antimicrobial activity of the tested antimicrobial substances was measured by the paper disc method. The DPPH free radical scavenging activities, the total phenolic content, and the characteristics (FT-IR, DSC and TGA) of the CBEFs were investigated. All of the samples significantly reduced E. coli, S. aureus and total viable counts, as compared with control during the storage time. Specifically, it was determined that hesperidin sprayed films showed an antimicrobial effect on E.coli growth and carotene sprayed films showed an antimicrobial effect on S. aureus growth. Growth of both bacterial species was highly inhibited (>50%) in the presence of 20% propolis. It was concluded that β-carotene, hesperidin and propolis can be substituted as natural preservatives in white cheese. With this advanced packaging technology, food safety can be ensured, the shelf life of the product can be extended and food losses in this sector can be reduced.

Optimization, Partial Purification, and Characterization of Bioactive Peptides of Lactobacillus paracasei Isolated from Traditional Egyptian Cheese

Background: Bacteriocins are small peptides which are ribosomally synthesized and have been shown to have wide range of antimicrobial activity. The aim of this study was to optimize the production of L. paracasei MG847589 bacteriocin. Furthermore, the potential antibacterial properties of the novel bacteriocins were characterized and evaluated against Staphylococcus aureus. Methods: The present study optimized the growth media constituents of Lactobacillus paracasei MG847589 to improve bacteriocin yield by applying One-Factor-at-a-Time (OFAT) and Response Surface Methodology (RSM) methods. Results: At OFAT, two-fold activity increased against Staphylococcus aureus in the presence of whey (22.5 g/L) as nitrogen source and sucrose (30 g/L) as carbon source. RSM tool was performed with media compounds using design expert 12.0.1.0. Whey (22.5 g/L), sucrose (30 g/L), temperature (30 ºC), and pH (6.5) condition yielded 25,600 AU/ml of bacteriocin against S. aureus. Bacteriocin was stable at pH range of 2.0 to 8.0 for one h and at 60 ºC for 15 min. The produced antimicrobial peptide is a novel bacteriocin with molecular mass of 2,611.122 Da. Conclusion: Bacteriocin of L. paracasei MG847589 isolated from traditional Egyptian cheese (Kareish) showed great antimicrobial activity and could be applied as food preservative in food manufacturing.

Evaluation of bacterial consortia associated with dairy fermentation by ribosomal RNA (rrn) operon metabarcoding strategy using MinION device

The ability of the third generation sequencing technologies to provide longer sequence reads contributes to the use of the longest possible amplicons as specific bacterial markers for metabarcoding studies. Nanopore sequencing technologies are increasingly used worldwide to profile microbiomes in environmental and food samples. The identification of beneficial or pathogenic bacteria in dairy fermented foods is related to their valuable health properties and also contributes to food safety issues. Here we described and optimised a PCR-based methodology of almost the entire ribosomal operon sequences (16S-ITS-23S) and their subsequent sequencing by MinION device. We used three different sequencing data processing and analysis strategies. Two of those utilized user-friendly software without the need of being conversant with any programming language. We tested all workflows on a simple mock community composed of a mixture of 7 bacterial DNA. Our scripted bioinformatics pipeline denoted as “AEROS”, representing an approach based on taxonomic classification with our reference database called AEROS-DB (Almost Entire Ribosomal Operon Sequences), was applied to traditional Slovak sheep cheese made from unpasteurized milk. All bacterial genera included in the mock community were detected with relatively small differences compared to the expected relative abundance using each of the three approaches. The AEROS approach provided more accurate composition data on this community at the species level as well. The results suggested that the use of almost entire rrn operon sequences in metabarcoding studies is suitable to analyze the bacterial consortia in cheeses and related dairy fermented products.

Major Causes of Variation of External Appearance, Chemical Composition, Texture, and Color Traits of 37 Categories of Cheeses.

Cheeses are produced by many different procedures, giving rise to many types differing in ripening time, size, shape, chemical composition, color, texture, and sensory properties. As the first step in a large project, our aim was to characterize and quantify the major sources of variation in cheese characteristics by sampling 1050 different cheeses manufactured by over 100 producers and grouped into 37 categories (16 with protected designation of origin, 4 traditional cheese categories, 3 pasta filata cheese categories, 5 flavored cheese categories, 2 goat milk categories, and 7 other categories ranging from very fresh to very hard cheeses). We obtained 17 traits from each cheese (shape, height, diameter, weight, moisture, fat, protein, water soluble nitrogen, ash, pH, 5 color traits, firmness, and adhesiveness). The main groups of cheese categories were characterized and are discussed in terms of the effects of the prevalent area of origin/feeding system, species of lactating females, main cheese-making technologies, and additives used. The results will allow us to proceed with the further steps, which will address the interrelationships among the different traits characterizing cheeses, detailed analyses of the nutrients affecting human health and sensorial fingerprinting.

Determination of safety status and probiotic properties ofEnterococcusstrains isolated from traditional cheeses in Turkey

This study aimed to evaluate the probiotic properties of Enterococcus strains isolated from Turkish traditional cheeses. Fifty-two Enterococcus spp. were taxonomically determined as follows: Enterococcus faecium (26), Enterococcus faecalis (18), Enterococcus durans (6), and Enterococcus italicus (2). The ability of isolates/strains to survive the harsh conditions (acidity and in-vitro gastric solution) of the gastrointestinal tract was established. They also showed auto-aggregation, hydrophobicity, and co-aggregation ability. Hydrophobicities of the strains were found between 0.8%-21%, 0.7%-56%, and 2%-63% for xylene, chloroform, and ethyl acetate, respectively. Autoaggregation values of the Enterococcus strains were 4%-20%, 7%-30%, and 36%-98% after 2, 4, and 24-h incubation, respectively. In this study, the Enterococcus strains tested showed co-aggregation ability with the Escherichia coli ATCC 25922, Salmonella Typhimurium ATCC 14028, and Staphylococcus aureus ATCC 25923. The results of PCR amplification revealed that only five strains possess virulence factor genes (gelE,asa1,cyl A,esp). We determined antibiotic resistance, biofilm forming abilities, and hemolytic activity for safety evaluation of strains. In this large and comprehensive study, we found that only few of Enterococcus strains have promising probiotic potential, among which E. faecalis ES1 and E. faecium EM1 showed the best probiotic properties (are the most promising probiotic candidates).

Complete Genome Sequences of Three Lactiplantibacillus plantarum Strains Isolated from Traditional Iranian Raw Milk Motal Cheese.

The complete genome sequences, as determined by a combination of short- and long-read sequencing, of three Lactiplantibacillus plantarum strains (M8, M17, and M19) that were isolated from Iranian motal cheese are reported. The genome sizes were estimated to be 3.3, 3.3, and 3.5 Mbp, respectively, with GC contents of approximately 44.5%.

Microbiological Quality and Safety of Traditional Raw Milk Cheeses Manufactured on a Small Scale by Polish Dairy Farms.

Polish raw milk artisanal cheese may pose a threat to consumer safety due to pathogen presence. The aim of this study was to assess the microbiological safety, quality and physicochemical composition of cow’s and goat’s milk fresh cheeses produced by farmers on a small scale. A total of 62 samples of six cheese types were analyzed for Listeria monocytogenes, Salmonella spp., lactic acid bacteria and coliform presence and concentration levels. The physicochemical analysis estimated energy, water, protein, fat, carbohydrate, ash and salt content. The cheeses were also tested for heavy metal contamination. Listeria monocytogenes and Salmonella spp. were not detected in any of the samples. Coliforms were present in all the goat’s milk cheeses and only in two of the cow’s milk cheeses. Low levels of cadmium, below 0.008 ppm, were detected in three of the cows’ milk samples. The raw milk cheeses studied were free of the pathogens examined and were of high nutritional value.

SCREENING OF ANTIBIOTIC RESISTANCE AND VIRULENCE GENES OF ENTEROCOCCUS SPP. STRAINS ISOLATED FROM URFA CHEESE

Enterococcus faecium, E. durans and E. faecalis species were isolated and identified from traditional Urfa cheese samples which were produced from unpasteurized raw milk. The enterococcal load of the cheese samples was between 4.4-5.6 log cfu g−1. High-level tetracycline, streptomycin, erythromycin, gentamycin, and penicillin resistance was determined in the enterococcal isolates. Multiple antibiotic resistance was also determined in E. faecalis (20.4%) and E. faecium (16.3%) strains. 36.7% of the enterococcal isolates were greater than 0.2 MAR index ratio in this study. The gelE and agg2 genes were found in 40 (81.63%) of the enterococcal isolates, whereas the vanB gene was found in 3 (6.12%) of the enterococcal isolates. The results indicate that the consumption of Urfa cheese, which is produced using raw milk, may have public health risk because of its antibiotic resistance characteristics and virulence genes of enterococcal biota.

Presence of Certain Foodborne Pathogens in Traditional Balearic Islands' Meat, Pastry, and Cheese Specialties Supported by European Union Quality Schemes, from 2018 to 2021.

The cuisine of the Balearic Islands (Spain, southern Europe) has several products of a great tradition, recognized worldwide and covered by European Union quality schemes, such as Protected Designation of Origin (PDO) and Protected Geographical Indication (PGI). Among them, the most emblematic products are sobrasada de Mallorca (a type of raw curated pork meat), ensaimada de Mallorca (pastry product), and Mahón-Menorca cheese (cow's milk cheese). During 4 consecutive years (2018-2021), the presence/absence of Escherichia coli β-glucuronidase positive (henceforth as E. coli), Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus in these products has been monitored, as well as the total yeast and mold count in ensaimada de Mallorca. The results of the microbiological analysis showed that sobrasada presented similar microbiological patterns to those of other raw curated meat products (some presence of E. coli and L. monocytogenes). Furthermore, the sobrasada de Mallorca made with white pork tended to be positive in E. coli compared to other sobrasada subtypes. In the case of ensaimada, only a reduced number of cases within filled ensaimadas (with higher moisture content) presented unacceptable mold and yeast counts (>500 colony-forming unit [CFU]/g). Finally, the Mahón-Menorca cheese presented a surprising microbiology pattern: higher E. coli contamination in the pasteurized milk cheese compared to its raw counterpart. This pattern was observed for all the years, being statistically significant in 2020. This study has detected good microbiological status in the three traditional products studied. However, worrisome issues in Good Hygienic Practices have been detected for some companies that produce pasteurized milk Mahón-Menorca cheese under the PDO quality label. The companies involved and even the competent authorities should address these problems to correct this deviation in food security.

Microbiological and chemical evaluation of dairy products commercialized in the Lebanese market.

Cheese is considered an essential component of the Lebanese table, however, several foodborne illnesses have been reported due to cheese consumption. This study aimed to assess the microbiological quality and the occurrence of antibiotic and pesticide residues in two traditional Lebanese cheeses, Akkawi and Baladiyeh. In addition, drug resistance of isolated pathogens from the cheese samples was evaluated. Fifty Akkawi and Baladiyeh cheese samples were obtained in duplicate from 37 different commercial brands in supermarkets and shops from various regions of Lebanon. Samples of different weights were either individually vacuum packed or soaked in brine unpacked where it was placed in plastic bag after being purchased. Samples were homogenized to determine antibiotic and pesticide residues using liquid and gas chromatography coupled to mass spectrometry, and microbiological evaluation was performed according to the International Organization for Standardization reference analytical methods. The disk diffusion method was used to determine the susceptibility of these isolates to antibiotics. Microbiologically, 17% of Akkawi and 14% of Baladiyeh samples were found to be non-conforming. The bacterial isolates (n = 29) were tested for their susceptibility to 11 different antibiotics commonly prescribed in the Lebanese community or used for treating infections caused by Gram-negative bacteria and listeriosis. Each isolate was found to be resistant to at least three antibiotics. Liquid and gas chromatography coupled to mass spectroscopy analysis showed the absence of pesticide residues in all samples. However, sulfamethazine antibiotic residue was found in 14% of the samples. The results suggest that the cheese samples tested could cause foodborne illnesses due to the detection of pathogenic bacteria and are a public health concern due to the presence of antibiotic residues and the transmission of multidrug-resistant organisms.

Isolation, identification, and antimicrobial activity of lactic acid bacteria associated with two traditional Colombian types of cheese: Quesillo and double-cream cheese

The Quesillo and Double-Cream, two traditional pasta filata fresh cheeses from the Colombian Andean region, were studied for their microbiological composition including lactic acid bacteria (LAB), volatile diacetyl and acetoin compounds, fatty acid profile, and antimicrobial activity against Listeria monocytogenes ATCC-7644 and Salmonella enterica subsp. enterica serovar Typhimurium ATCC-13311. The counts of indicator microorganisms were consistent with those found in this product. The fatty acid composition varied, with oleic and palmitic acids having the largest concentrations. The aroma precursor compound acetoin was detected in both kinds of cheese. The most prevalent species in both products was Lactococcus lactis, which was followed by Enterococcus faecium and Limosilactobacillus fermentum. The inhibition against the pathogens under study was seen in the cell-free supernatants of L. lactis (Quesillo 37–41), L. fermentum (Quesillo 40–74; Double-Cream 104) and Lacticaseibacillus paracasei (Double-Cream 101) with good activity at pH 7.0 and 60 °C. The antimicrobial activity of L. paracasei (Double-Cream 101) and L. fermentum (Double-Cream 104) against Listeria monocytogenes at all temperatures and times analyzed was highlighted. These findings suggest that the LAB used in this study, which was derived from artisanal cheeses, has bioprospecting potential for application in the elaboration of these traditional products and new dairy products.

Screening of Wild Lactic Acid Bacteria from Algerian Traditional Cheeses and Goat Butter to Develop a New Probiotic Starter Culture.

Twenty-five lactic acid bacterial (LAB) strains have been isolated from traditional goat butter and three types of cheese (dry Klila, frech Klila, and Bouhezza) and evaluated for technological abilities, probiotic properties, and potentials as starter cultures. The twenty-five LAB strains comprised eight strains belonging to Lactobacillus, four strains belonging to Lactococcus, eleven strains belonging to Enterococcus, and two strains belonging to Leuconostoc. A non-hierarchical cluster analysis was performed in order to select the performing strains. After carrying out the preliminary phenotypic characterizations and the probiotic potential, three strains designated as BM10, B15, and C30 belonging to the genus Lactobacillus and Enterococcus with good tolerance to acidity were selected. The strains showed a significant resistance to 0.5% bile salts and 0.4% phenol. Hemolytic activity was not detected; in addition, good hydrophobicity and autoaggregation was obtained. A significant antimicrobial activity was exhibited by all selected strains against Listeria innocua. Genotypic identification by 16S rRNA allowed the identification of B15, BM10, and C30 as Lactobacillus plantarum, Lactobacillus casei, and Enterococcus durans, respectively. The results of the current study suggest that the strains isolated from Algerian fermented dairy products have high potential as probiotic starter cultures in the goat butter and cheese industry.

Acceptability of a sustainable technological innovation applied to traditional soft cheese: Information concerning the benefits for health and the environment can compensate for a lower hedonic appreciation

The objective of this work was to study the reaction of consumers to a technological innovation (a radically new manufacturing process) applied to a traditional product (cheese). A traditional cheese and two cheeses resulting from a new sustainable process were evaluated by 142 consumers. These cheeses were first evaluated blind, giving rise to liking score and willingness to pay (WTP). Following a message concerning the nature of the processes used for the three cheeses, the consumers gave their WTP once again. The last two stages of the protocol consisted of successively revealing two pieces of information concerning the benefits of the new process for health and the environment and in measuring, at each of these two stages, the WTP of the consumers. Blind tasting showed that the two new cheeses were less appreciated than the traditional cheese. The information concerning the nature of the processes used did not significantly influence the WTP of the new cheeses but caused a revaluation of the traditional cheese. Information on the benefits of the new process has reduced the gap between the WTP of the three cheeses by decreasing the WTP for the traditional cheese and increasing the WTP for the new cheeses. This information made it possible to compensate for differences in liking of 1 to 2 points on a scale of 10. However, there is heterogeneity in consumer reactions. Indeed, some consumers (23%) did not appreciate the sensory properties of the new cheeses, and despite the assimilation of the information concerning the benefits of the new process, their WTP remained lower than those of traditional cheese. These results show that there is no major opposition to the application of technological innovations to traditional products such as cheese and that information concerning health and environmental benefits is positively accepted.

Evaluation of technological properties and selection of wild lactic acid bacteria for starter culture development

Sixty-six lactic acid bacteria strains, isolated from traditional cheeses, were identified by MALDI-TOF technology, characterised through the evaluation of their enzymatic activities (acidifying and proteolytic capacities and carboxypeptidase, aminopeptidase, dipeptidase and esterase activities) and selected through a scoring system based on activity results in order to select wild strains of technological interest for cheese manufacturing. The strains were identified as Lactococcus lactis (9), Leuconostoc citreum (3), Leuconostoc mesenteroides (2), Leuconostoc pseudomesenteroides (1), Levilactobacillus brevis (7), Lactiplantibacillus plantarum (32), Lactiplantibacillus paraplantarum (7) and Lacticaseibacillus paracasei (5). In general, Lactococcus lactis strains showed the highest degree of acidifying activity, especially in the first hours of fermentation, and extracellular proteolytic activity. In contrast, intracellular activities, assayed from cell-free extracts, were higher in the lactobacilli strains. L. paracasei strains showed the highest level of aminopeptidase activity, while some L. plantarum strains obtained high values of dipeptidase activity. Carboxypeptidase activity was very low or undetectable in many strains, although in others the activity values were exceptionally high. Esterolytic activity was generally low, although L. paracasei strains showed higher activity on short-chain substrates. Finally, 11 strains were selected using the scoring system that could be used in the design of starter cultures and co-cultures.