Assessment of Different Levels of Blackcurrant Juice and Furcellaran on the Quality of Fermented Whey-Based Beverages Using Rheological and Mechanical Vibration Damping Techniques.

In the current study, fermented whey-based beverage models with different levels of blackcurrant juice (0; 10; 20; 100% (w/w)) and furcellaran (0.25% and 0.50% (w/w)) were produced and evaluated. Physicochemical, rheological, mechanical vibration damping, and sensory analyses were performed. During fermentation (48 h), the values of pH, density, and total soluble solids decreased. On the other hand, the ethanol content during fermentation increased up to a final content in the range of 0.92-4.86% (v/v). The addition of furcellaran was effective in terms of sediment content decrease to a level of 0.25% (w/w). In general, the samples exhibited non-Newtonian pseudoplastic behaviour. The sensory analysis revealed that the sample with a composition of 20% (w/w) blackcurrant juice and 0.50% (w/w) furcellaran received the highest score.

Effect of Inoculation with Autochthonous Lactic Acid Bacteria on Flavor, Texture, and Color Formation of Dry Sausages with NaCl Partly Substituted by KCl.

The effects of inoculating lactic acid bacteria (LAB), specifically Lactiplantibacillus plantarum, Latilactobacillus sakei, Latilactobacillus curvatus, and Weissella hellenica on the flavor, texture, and color formation of dry sausages in which NaCl was partially substituted by 40% KCl, were explored in this study. It was found that LAB inoculation increased the presence of ketones, alcohols, acids, esters, and terpenes. It also reduced the pH, moisture, protein, and fat content, improving the b*-value, flavor, and texture of the sausages. Notably, L. sakei inoculation showed the most significant improvement in dry sausages with NaCl substitutes, especially on the reduction of bitterness. Meanwhile, there was a close positive correlation between the LAB count with the alcohols and esters formation of dry sausage with NaCl substitution (p < 0.05). These findings offer insight into improving the product characteristics of dry sausages using NaCl substitutes.

Genomic exploration of the fermented meat isolate Staphylococcus shinii IMDO-S216 with a focus on competitiveness-enhancing secondary metabolites.

BACKGROUND: Staphylococcus shinii appears as an umbrella species encompassing several strains of Staphylococcus pseudoxylosus and Staphylococcus xylosus. Given its phylogenetic closeness to S. xylosus, S. shinii can be found in similar ecological niches, including the microbiota of fermented meats where the species may contribute to colour and flavour development. In addition to these conventional functionalities, a biopreservation potential based on the production of antagonistic compounds may be available. Such potential, however, remains largely unexplored in contrast to the large body of research that is available on the biopreservative properties of lactic acid bacteria. The present study outlines the exploration of the genetic basis of competitiveness and antimicrobial activity of a fermented meat isolate, S. shinii IMDO-S216. To this end, its genome was sequenced, de novo assembled, and annotated. RESULTS: The genome contained a single circular chromosome and eight plasmid replicons. Focus of the genomic exploration was on secondary metabolite biosynthetic gene clusters coding for ribosomally synthesized and posttranslationally modified peptides. One complete cluster was coding for a bacteriocin, namely lactococcin 972; the genes coding for the pre-bacteriocin, the ATP-binding cassette transporter, and the immunity protein were also identified. Five other complete clusters were identified, possibly functioning as competitiveness factors. These clusters were found to be involved in various responses such as membrane fluidity, iron intake from the medium, a quorum sensing system, and decreased sensitivity to antimicrobial peptides and competing microorganisms. The presence of these clusters was equally studied among a selection of multiple Staphylococcus species to assess their prevalence in closely-related organisms. CONCLUSIONS: Such factors possibly translate in an improved adaptation and competitiveness of S. shinii IMDO-S216 which are, in turn, likely to improve its fitness in a fermented meat matrix.

Amino acid profile behavior during the fermentation of Criollo cocoa beans.

The study investigated the behavior of seventeen amino acids during spontaneous (SF) and starter culture (SC) fermentation of Criollo cocoa beans from Copallín, Guadalupe and Tolopampa, Amazonas-Peru. For this purpose, liquid chromatography (UHPLC) was used to quantify amino acids. Multivariate analysis was used to differentiate the phases of the fermentation process. The percentage of essential amino acids during SC fermentation (63.4%) was higher than SF (61.8%); it was observed that the starter culture accelerated their presence and increased their concentration during the fermentation process. The multivariate analysis identified a first stage (day 0 to day 2), characterized by a low content of amino acids that increased due to protein hydrolysis. The study showed that adding the starter culture (Saccharomyces cerevisiae) to the fermentation mass increased the concentration of essential amino acids (63.0%) compared to the spontaneous process (61.8%). Moreover, this addition reduced the fermentation time (3-4 days less), demonstrating that the fermentation process with a starter culture allows obtaining a better profile of amino acids precursors of flavor and aroma.

Date Vinegar: First Isolation of Acetobacter and Formulation of a Starter Culture.

There is a lack of scientific analysis and control over the production of date vinegar in Oman, despite its growing demand in the worldwide market. Traditional production of date vinegar may lead to elevated amounts of ethanol (≥0.5%) and reduced content of acetic acid (<4%) compared to the standard acceptable levels. This study aimed to isolate non-Gluconobacter species from date vinegar produced by spontaneous fermentation and formulate starter cultures for quick and efficient production of date vinegar. In spontaneous fermentation date vinegar samples, the highest concentration of acetic acid was 10.42% on day 50. Acetobacter malorum (5 isolates), A. persici (3 isolates), and A. tropicalis (3 isolates) were identified based on 16S rRNA gene sequences for the first time in date vinegar. For date vinegar prepared with a starter culture of Acetobacter and yeast, the highest concentration of acetic acid was 4.67%. In conclusion, spontaneous fermentation resulted in the production of date vinegar with a high concentration of acetic acid, acceptable concentrations of ethanol and methanol, and the first isolation of three Acetobacter species. The formulated starter culture produced acceptable amounts of acetic acid and the time of fermentation was reduced 10 times (from 40 days to 4 days). This can provide the basis for producing a personalized or commercial product that ensures the production of good-quality date vinegar in an easier, faster, safer, and more efficient way from low-quality and surplus dates.

Two Debaryomyces hansenii strains as starter cultures for improving the nutritional and sensory quality of dry-cured pork belly.

Dry-cured meat products are gaining attention owing to their distinctive sensory characteristics and health benefits. In this study, two Debaryomyces hansenii strains were investigated for their potential as starter cultures for dry-cured pork belly products. After preliminary screening, these D. hansenii strains, namely, S20 and S26, both exhibiting with excellent aroma-producing capacity in a dry-cured meat model, were selected as single-strain starter cultures. For comparison, a non-inoculated control was also evaluated. In S20- and S26-inoculated pork belly, yeast dominated the microbiota and improved microbiological safety by suppressing Enterobacteriaceae growth. Compared with the non-inoculated control, the inoculated pork belly yielded higher hardness and redness (a*) values. Starter culture inoculation accelerated proteolysis in pork belly, improving the content of total free amino acids (TFFAs) and several essential free amino acids (Thr, Val, Met, Ile, Leu, and Phe) at the end of processing. Moreover, the inoculated samples exhibited higher levels of fat oxidation-derived aldehydes as well as esters, acids, alcohols and other compounds than the non-inoculated control at the end of the 95-day ripening period. Overall, these findings provide new insights into the application of D. hansenii isolated from dry-cured ham to dry-cured pork belly.

Development of a defined mixed starter culture for the improvement of Tej, Ethiopian honey wine.

Ethiopian honey wine, Tej, is the most popular traditionally fermented alcoholic beverage in Ethiopia. Owing to the spontaneous fermentation process, the final product is neither predictable nor consistent in quality. Attempts have not been made before to solve this problem. Thus, the aim of this study was to develop a potential mixed starter culture of yeast and lactic acid bacteria isolated from Tej samples for the production of Tej with consistent quality. One hundred seventy-seven lactic acid bacteria and 194 yeasts were isolated from 30 Tej samples collected from southwest Ethiopia. After sequentially testing the isolates towards physiological stress tolerance and desired metabolic products, 10 lactic acid bacteria and 10 yeast isolates were screened. Later, four lactic acid bacteria and four yeast isolates were found to be compatible in co-culture tests. Finally, the combination of lactic acid bacteria and yeast isolates was formulated using the design of expert version 7.0.0 software, and six formulates (F #1-6) were designed. Controlled Tej fermentation was performed under laboratory conditions using six lactic acid bacteria-yeast starter culture formulations. The sensory attributes, in terms of color, flavor, odor, turbidity, and overall acceptance analysis scored 4.8/5.0 (F #2) and 4.7/5.0 (F #6), with mean significant variations (p < 0.05) among the other formulates. These two formulates were considered the best-mixed starter cultures compared to the control and other formulates. Matrix-assisted laser desorption ionization-time of flight analysis revealed that the lactic acid bacteria starters (AAUL7 and AAUL10) belonged to Lactobacillus paracasei. While the yeast starters (AAUY2 and AAUY8) belonged to Saccharomyces cerevisiae. These mixed lactic acid bacteria-yeast starter cultures could be used as the best starter culture for the fermentation of Ethiopian honey wine, Tej, with consistent quality.

Effect of Starter Culture and Temperature on the Flavor and Sensory Characteristics of Dry-Cured Ham.

This study focused on understanding the effects of yeast and mold on the sensory properties of dry-cured ham aged at 20°C and 25°C. Debaryomyces hansenii isolated from Doenjang and fermented sausages, and Penicillium nalgiovense isolated from fermented sausages were utilized. The CIE a* tended to increase in all treatments as the aging period increased. At 6 weeks of aging, DFD25 showed a significantly higher CIE a* value than other treatments. The shear force tended to increase in all treatments as the aging period increased. At 6 weeks of aging, among the treatments aged at 25°C, DFD25 showed a low tendency to shear force. The PC1 of the electronic nose was 42.872%. At 25°C, the hexane content was higher and levels of ethanol, propan-2-one, 2,4,5-trimethylthiazole, and limonene were lower than that at 20°C. DFD25 showed significantly higher hexane content and significantly lower limonene content than other treatments. The PC1 of the electronic tongue was 84.529%. All treatments, except for the C starter, exhibited higher salt and lower sour levels at 25°C compared to 20°C when the same starter was used. The DFD25 showed the lowest sour taste and a higher tendency of umami than the other treatments. Sensory evaluation revealed that DFD25 had significantly higher scores for texture than C25, whereas no significant differences were observed in other aspects. Therefore, the used starters are considered suitable for aging at 25°C; among them, the DFD starter demonstrates superior qualities and enhanced commercial potential compared to the control.

Draft genome sequences of 53 Lactococcus and Leuconostoc strains isolated from two undefined DL-starter cultures.

This study presents the complete genomes of 53 strains of Lactococcus and Leuconostoc isolated from two undefined DL-starter cultures originating from Denmark, Tistrup, and P. The genomes were reconstructed using long-read, nanopore-based DNA sequencing, delivering comprehensive data set for comparative genomics and taxonomic classification, with potential utility in dairy fermentation processes.

A review on fermented vegetables: Microbial community and potential upgrading strategy via inoculated fermentation.

Fermentation is a traditional method utilized for vegetable preservation, with microorganisms playing a crucial role in the process. Nowadays, traditional spontaneous fermentation methods are widely employed, which excessively depend on the microorganisms attached to the surface of raw materials, resulting in great difficulties in ideal control over the fermentation process. To achieve standardized production and improve product quality, it is essential to promote inoculated fermentation. In this way, starter cultures can dominate the fermentation processes successfully. Unfortunately, inoculated fermentation has not been thoroughly studied and applied. Therefore, this paper provides a systematic review of the potential upgrading strategy of vegetable fermentation technology. First, we disclose the microbial community structures and succession rules in some typical spontaneously fermented vegetables to comprehend the microbial fermentation processes well. Then, internal and external factors affecting microorganisms are explored to provide references for the selection of fermented materials and conditions. Besides, we widely summarize the potential starter candidates with various characteristics isolated from spontaneously fermented products. Subsequently, we exhibited the inoculated fermentation strategies with those isolations. To optimize the product quality, not only lactic acid bacteria that lead the fermentation, but also yeasts that contribute to aroma formation should be combined for inoculation. The inoculation order of the starter cultures also affects the microbial fermentation. It is equally important to choose a proper processing method to guarantee the activity and convenience of starter cultures. Only in this way can we achieve the transition from traditional spontaneous fermentation to modern inoculated fermentation.

Evaluation of stress tolerance and design of alternative culture media for the production of fermentation starter cultures in cacao.

Ecuador is one of the world's leading producers of cacao beans, and Nacional x Trinitario cacao represents one of the most distinctive varieties due to its flavor and aroma characteristics. This study aimed to evaluate the effect of the starter culture isolated from microbial diversity during the spontaneous fermentation of Nacional x Trinitario cacao. A total of 249 microbial isolates were obtained from spontaneous culture, with Lactiplantibacillus (45 %), Saccharomyces (17 %), and Acetobacter (2 %) being the most relevant genera for fermentation. Tolerance tests were conducted to select microorganisms for the starter culture. Lactiplantibacillus plantarum exhibited the highest tolerance at pH 5 and 6 % ethanol and tolerated concentrations up to 15 % for glucose and fructose. Acetobacter pasteurianus grew at pH 2 and 6 % ethanol, tolerating high sugar concentrations of up to 15 % for glucose and 30 % for fructose, with growth observed in concentrations up to 5 % for lactic and acetic acid. Subsequently, a laboratory-scale fermentation was conducted with the formulated starter culture (SC) comprising S. cerevisiae, L. plantarum, and A. pasteurianus, which exhibited high tolerance to various stress conditions. The fermentation increased alcoholic compounds, including citrusy, fruity aromas, and floral notes such as 2-heptanol and phenylethyl alcohol, respectively 1.6-fold and 5.6-fold compared to the control. Moreover, the abundance of ketones 2-heptanone and 2-nonanone increased significantly, providing sweet green herbs and fruity woody aromas. Cacao fermented with this SC significantly enhanced the favorable aroma-producing metabolites characteristic of Fine-aroma cacao. These findings underscore the potential of tailored fermentation strategies to improve cacao product quality and sensory attributes, emphasizing the importance of ongoing research in optimizing fermentation processes for the cacao industry.

Developing defined starter culture for reproducible profile of flavour compound in Chinese xiaoqu baijiu fermentation.

Defined starter cultures, containing selected microbes could reduce the complexity of natural starter, are beneficial for controllable food fermentations. However, there are challenges in identifying key microbiota and constructing synthetic microbiota for traditional food fermentations. Here, we aimed to develop a defined starter culture for reproducible profile of flavour compounds, using Chinese Xiaoqu Baijiu fermentation as a case. We classified all microbes into 4 modules using weighted correlation network analysis. Module 3 presented significant correlations with flavour compounds (P < 0.05) and the highest gene abundance related with flavour compound production. 13 dominant species in module 3 were selected for mixed culture fermentation, and each species was individually deleted to analyse the effect on flavour compound production. Ten species, presenting significant effects (P < 0.05) on flavour compound production, were selected for developing the starter culture, including Rhizopus oryzae, Rhizopus microsporus, Saccharomyces cerevisiae, Pichia kudriavzevii, Wickerhamomyces anomalus, Lactobacillus acetotolerans, Levilactobacillus brevis, Weissella paramesenteroides, Pediococcus acidilactici, and Leuconostoc pseudomesenteroides. After optimising the structure of the starter culture, the profile similarity of flavour compounds produced by the starter culture reached 81.88% with that by the natural starter. This work indicated feasibility of reproducible profile of flavour compounds with defined starter culture for food fermentations.

Study of the Microbiome of the Cretan Sour Cream Staka Using Amplicon Sequencing and Shotgun Metagenomics and Isolation of Novel Strains with an Important Antimicrobial Potential.

Staka is a traditional Greek sour cream made mostly from spontaneously fermented sheep milk or a mixture of sheep and goat milk. At the industrial scale, cream separators and starter cultures may also be used. Staka is sometimes cooked with flour to absorb most of the fat. In this study, we employed culture-based techniques, amplicon sequencing, and shotgun metagenomics to analyze the Staka microbiome for the first time. The samples were dominated by Lactococcus or Leuconostoc spp. Most other bacteria were lactic acid bacteria (LAB) from the Streptococcus and Enterococcus genera or Gram-negative bacteria from the Buttiauxella, Pseudomonas, Enterobacter, Escherichia-Shigella, and Hafnia genera. Debaryomyces, Kluyveromyces, or Alternaria were the most prevalent genera in the samples, followed by other yeasts and molds like Saccharomyces, Penicillium, Aspergillus, Stemphylium, Coniospotium, or Cladosporium spp. Shotgun metagenomics allowed the species-level identification of Lactococcus lactis, Lactococcus raffinolactis, Streptococcus thermophilus, Streptococcus gallolyticus, Escherichia coli, Hafnia alvei, Streptococcus parauberis, and Enterococcus durans. Binning of assembled shotgun reads followed by recruitment plot analysis of single reads could determine near-complete metagenome assembled genomes (MAGs). Culture-dependent and culture-independent analyses were in overall agreement with some distinct differences. For example, lactococci could not be isolated, presumably because they had entered a viable but not culturable (VBNC) state or because they were dead. Finally, several LAB, Hafnia paralvei, and Pseudomonas spp. isolates exhibited antimicrobial activities against oral or other pathogenic streptococci, and certain spoilage and pathogenic bacteria establishing their potential role in food bio-protection or new biomedical applications. Our study may pave the way for additional studies concerning artisanal sour creams to better understand the factors affecting their production and the quality.

Meat Starter Culture Reduces Aspergillus parasiticus Production of Aflatoxins on Meat-Based and Salami Model Media.

There is great concern about the risk posed by the consumption of food contaminated with aflatoxins (AF), produced mostly by Aspergillus strains, that can also be found in dry-fermented meat products (DFMPs). The aim of this study was to investigate the inhibitory effect of meat starter culture (SC), frequently used for fermentation in the meat industry, on A. parasiticus growth and the production of aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2), and sterigmatocystin (STE) on different meat-based (CMA) and salami model (SM-G) media. Incubation was carried out under optimal conditions for fungal growth and under typical conditions for ripening of DFMPs for 21 days. Reversed-phase UPLC-MS/MS analysis was performed to determine mycotoxin production. SC reduced A. parasiticus growth more on CMA than on SM-G media. AFB1 formation was inhibited on both types of SC-containing media, although SC generally had a stronger inhibitory effect on AFB1 production on CMA than on SM-G. AFB1 and AFB2 were produced on CMA, while AFB1 dominated in SM-G, AFG1, and AFG2 were not detected in any media. The results show that SC inhibited AFB1 formation of A. parasiticus on SM-G media after 21 days of incubation under typical conditions for the production of DFMPs. These results indicate the necessity to investigate AF on natural matrices in an environment that is as similar as possible to real conditions in the production of DFMPs.

Genomic Characterization of Wild Lactobacillus delbrueckii Strains Reveals Low Diversity but Strong Typicity.

Investigating the diversity of a given species could give clues for the development of autochthonous starter cultures. However, few studies have focused on the intraspecies diversity of Lactobacillus delbrueckii strains, a technologically important lactic acid bacterium for the dairy industry. For this reason, Lactobacillus delbrueckii strains from the Saint-Nectaire Protected Designation of Origin (PDO) area were isolated and characterized. Genetic diversity was determined based on core genome phylogenetic reconstruction and pangenome analysis, while phenotypic assessments encompassed proteolysis and volatile compound production potential. A total of 15 L. delbrueckii ssp. lactis unique new strains were obtained. The genetic analysis and further proteolytic activities measurement revealed low variability among these Saint-Nectaire strains, while substantial genetic variability was observed within the L. delbrueckii ssp. lactis subspecies as a whole. The volatile compound profiles slightly differed among strains, and some strains produced volatile compounds that could be of particular interest for cheese flavor development. While the genetic diversity among Saint-Nectaire strains was relatively modest compared to overall subspecies diversity, their distinct characteristics and pronounced differentiation from publicly available genomes position them as promising candidates for developing autochthonous starter cultures for cheese production.

Fermentation of coffee fruit with sequential inoculation of Lactiplantibacillus plantarum and Saccharomyces cerevisiae: effect on sensory attributes and chemical composition of the beans.

This study has innovative aspects related to the use of sequential inoculation technique in the coffee bean fermentation process: the inoculation of Lactiplantibacillus plantarum followed by Saccharomyces cerevisiae, in the fermentation of coffee fruit for the production of specialty natural coffees. The objective was to evaluate the effect of this technique and of the total fermentation time on the sensory attributes of the coffee beverage and on the organic acid profile, bioactive compounds, and fatty acid profile of the beans. The fermentation of coffee fruit with sequential inoculation resulted in greater acidity of the beverage and contributed to increases of up to 2 points in coffee fermented. The total fermentation time was directly related to the organic acid content, and the longer the total fermentation time was, the greater the organic acid content. The fatty acid content and bioactive compound content showed little variation among treatments.

Characterization of yeast mutant strains for starter culture in Arabica coffee fermentation.

Arabica coffee is the most popular and best-selling type of coffee. During coffee fermentation, microorganisms are essential for the production of metabolites and volatile compounds that affect coffee flavor quality. This work aimed to study the mutation, selection, and characterization of the Wickerhamomyces anomalus strain YWP1-3 as a starter culture to enhance the flavor quality of Arabica coffee. The results revealed that six mutants could produce relatively high levels of the pectinase enzyme on pectin agar media and exhibited high activity levels, ranging from 332.35 to 415.88 U/ml in mucilage broth. Strains UV22-2, UV22-3, UV41-1 and UV32-1 displayed higher levels of amylase activity than did the wild type. The UV22-2 and UV22-3 mutants exhibited the highest pectin degradation indices of 49.22% and 45.97%, respectively, and displayed significantly enhanced growth rates in nitrogen yeast base media supplemented with various sugars; thus, these mutants were evaluated for their ability to serve as a starter for fermentation of Arabica coffee. The cupping scores of coffees derived from UV22-2 and UV22-3 were 83.5 ± 1.5 and 82.0 ± 2.14, respectively. The volatile compounds in the roasted coffee fermented by UV22-2 were analyzed by GC‒MS, which revealed higher levels of furfuryl alcohol and furfuryl acetate than did the other samples. These findings suggested that UV22-2 could be an influential starter culture for Arabica coffee fermentation.

Fermentation of coffee fruit with sequential inoculation of Lactiplantibacillus plantarum and Saccharomyces cerevisiae: Effects on volatile composition and sensory characteristics.

Mixed starter cultures of lactic acid bacteria and yeasts used in the production of fermented foods, including coffee, can improve the sensory quality and food safety. The objective of this study was to evaluate the effects of fermentation of coffee with inoculation of Lactiplantibacillus plantarum followed by Saccharomyces cerevisiae and the effects of fermentation time on the aroma and flavor of the coffee beverage and on the volatile composition of the roasted coffee beans. The coffee was fermented for 48 h or 96 h after inoculation of Lactiplantibacillus plantarum followed by inoculation of Saccharomyces cerevisiae or the respective controls. The aroma and flavor of the coffee beverage fermented with sequential inoculation showed complexity, with a predominance of fruity and fermented sensory notes. Forty-seven volatile compounds were identified. In addition, the sequentially inoculated coffees had greater formation of volatiles and led to greater perception of fruity and fermented flavor and aroma.

Enhancement of fermented sausage quality driven by mixed starter cultures: Elucidating the perspective of flavor profile and microbial communities.

The metabolic activities of microorganisms play a crucial role in the quality development of fermented sausage. This study investigated the effect of inoculation with different combinations of starter cultures (Lactiplantibacillus plantarum YR07, Latilactobacillus sakei L.48, Staphylococcus xylosus S.14, and Mammaliicoccus sciuri S.18) on the quality of sausages. Inoculation with mixed starter cultures promoted protein degradation to generate amino acids and the conversion to volatile compounds, which enhanced the flavor development in fermented sausages. The bacterial community analyses demonstrated that the inoculation of mixed starter cultures could inhibit the growth of spoilage and pathogenic bacteria, thereby reducing the total content of biogenic amines. The correlation analysis between the core bacteria and characteristic volatile compounds revealed that fermented sausages inoculated with Lactobacillus and coagulase negative staphylococci exhibited significant positive correlations with the majority of key characteristic volatile compounds. In four treatments, inoculation with L. plantarum YR07 and M. sciuri S.18 greatly promoted the formation of characteristic volatile compounds (3-hydroxy-2-butanone, hexanal, and 1- octen-3ol). Therefore, the combined inoculation of L. plantarum YR07 and M. sciuri S.18 is promising to enhance fermented sausage's flavor profile and safety.

The Role of Autochthonous Levilactobacillus brevis B1 Starter Culture in Improving the Technological and Nutritional Quality of Cow's Milk Acid-Rennet Cheeses-Industrial Model Study.

In the study, an attempt was made to develop an innovative technology for cheese manufacturing. It was hypothesized that selected autochthonous lactic acid bacteria as a starter culture are more suitable for the production of acid-rennet cheeses of good technological and sensory quality. The study aimed to assess the possibility of using the strain Levilactobacillus brevis B1 (L. brevis B1) as a starter culture to produce acid-rennet cheeses using raw cow's milk. Two variants of cheese were manufactured. The control variant (R) was coagulated with microbial rennet and buttermilk, and the other variant (B1) was inoculated with rennet and L. brevis B1 starter culture. The effect of the addition of these autochthonous lactic acid bacteria on selected physicochemical characteristics, durability, the composition of fatty acids, cholesterol, Iipid Quality Indices, and microbiological and sensory quality of acid-rennet cheeses was determined during a 3-month period of storage. The dominant fatty acids observed in the tested cheeses were saturated fatty acids (SFA) (68.43-69.70%) and monounsaturated fatty acids (MUFA) (25.85-26.55%). Significantly higher polyunsaturated fatty acid (PUFA) content during storage was observed for B1 cheeses. The B1 cheeses were characterized by lower cholesterol content compared to cheese R and showed better indexes, including the Index of atherogenicity, Index of thrombogenicity, DFA, OFA, H/H, and HPI indexes, than the R cheese. No effect of the tested L. brevis B1 on sensory quality was observed in relation to the control cheeses during 3 months of storage. The results of the research indicate the possibility of using the L. brevis B1 strain for the production of high-quality, potentially probiotic acid-rennet cheeses.