Fermented Dairy Products: Processing Technology, Microbiology and Health Benefits

Background: White brined cheese is one of the most frequently consumed cheeses that is accepted among a large group of consumers, which is largely related to its unique sensory properties, which are characterized by specific technological processes including ripening in the brine. Thus, white brined cheese contains a high amount of NaCl, and frequent consumption might lead to excessive sodium intake, which nowadays, presents a global problem. Consequently, food industries have developed reduced sodium products by substitutional salts. Furthermore, various studies have indicated that increased sodium intake via the diet can be associated with cardiovascular diseases, a risk of digestive system cancer, obesity, and other conditions. Calcium salts (citrate and lactate) are safe for human health and can be added to various foods according to the quantum satis rule. The present study aimed to partially replace NaCl with Ca-citrate and Ca-lactate in proportions of 25% and 50%. Additionally, the study presents the possibility of applying Artificial Neural Network (ANN) models for the prediction of some brine and cheese properties. Methods: White brined cheese with substitutional salts in brine (25% and 50% Ca-citrate and 25% and 50% Ca-lactate) were produced and compared to the control cheese ripened in conventionally applied NaCl brine. The acidity, total dissolved solids, salt amount, conductivity, color, and textural and sensory properties were determined over the 28 days of cold storage. Results: The substitution of NaCl with Ca-citrate and Ca-lactate is promising for sodium reduction in white brined cheese, whereby the physical and chemical properties remain acceptable. The best sensory score gain occurred with a substitution of 25% NaCl with Ca-citrate. Furthermore, ANN models can be employed to predict brine and cheese properties during storage. Full article

In this study, we used culture-independent analysis based on 16S rRNA gene amplicons and metagenomics to explore in depth the microbial communities and their metabolic capabilities of artisanal brine cheeses made in the North Caucasus. Additionally, analysis of organic acid profiles was carried out for cheese characterization. Twelve cheese samples (designated as 05SR–16SR) from various artisanal producers were taken from five different villages located in Northern Ossetia–Alania (Russia). These cheeses were made using methods based on cultural traditions inherited from previous generations and prepared using a relatively uncontrolled fermentation process. The microbial diversity of Caucasus artisanal cheeses was studied for the first time. The results showed a diverse composition in all cheeses, with Bacillota (synonym Firmicutes) (9.1–99.3%) or Pseudomonadota (synonym Proteobacteria) (0.2–89.2%) prevalence. The microbial communities of the majority of the studied cheeses were dominated by lactic acid bacteria (LAB) genera, like Lactococcus (10.3–77.1% in 07SR, 09SR, 10SR, 11SR, 13SR, 15SR, 16SR), Lactobacillus (54.6% in 09SR), Streptococcus (13.9–93.9% in 11SR, 13SR, 14SR, 15SR), Lactiplantibacillus (13.4–30.6% in 16SR and 07SR) and Lentilactobacillus (5.9–14.2% in 09SR, 10SR and 13SR). Halophilic lactic acid bacteria belonging to the Tetragenococcus genus accounted for 7.9–18.6% in 05SR and 06SR microbiomes. A distinctive feature of Ossetia cheese microbiomes was the large variety of halophilic proteobacteria, and in some cheeses they prevailed, e.g., Chromohalobacter (63–76.5% in 05SR and 06SR), Psychrobacter (10–47.1% in 08SR, 11SR, 12SR), Halomonas (2.9–33.5% in 06SR, 08SR, 11SR and 12SR), Marinobacter (41.9% in 12SR) or Idiomarina (2.9–14.4% in 06SR, 08SR and 11SR samples). Analysis of the genomes assembled from metagenomes of three cheeses with different bacterial composition revealed the presence of genes encoding a variety of enzymes, involved in milk sugar, proteins and lipid metabolism in genomes affiliated with LAB, as well as genes responsible for beneficial bioamine and bacteriocin synthesis. Also, most of the LAB did not contain antibiotic resistance genes, which makes them potential probiotics, so highly demanded nowadays. Analysis of the genomes related to halophilic proteobacteria revealed that they are not involved in milk fermentation; however, the search for “useful” genes responsible for the synthesis of beneficial products/metabolites was partially positive. In addition, it has been shown that some halophiles may be involved in the synthesis of inappropriate bioactive components. The results obtained by culture-independent analyses confirm the importance of using such techniques both to clarify the quality and health-promoting properties of the product, and to look for probiotic strains with specified unique properties. This study has shown that traditional dairy foods may be a source of such beneficial strains. Full article

Nipple fruit (Solanum mammosum) has been considered to have great pharmaceutical potential because of its high amounts of solamargine and solasonine. This study aimed to examine the effect of nipple fruit at different concentrations (0.5%, 1%, and 2% (w/v)) on the viability, acid, bile, lysozyme, and gastric juice tolerance, and protease activity of Lactobacillus acidophilus LA K. The viability was studied in MRS broth. Acid tolerance was determined by adjusting the pH to 2, whereas bile tolerance was examined with oxgall 0.3% (w/v) in MRS broth. Lysozyme resistance was investigated in an electrolyte solution with lysozyme (100 mg/L), while gastric juice tolerance was analyzed with pepsin and NaCl. Protease activity was determined spectrophotometrically at 340 nm in skim milk with o-phthaldialdehyde reagent. L. acidophilus LA K was incubated anaerobically (37 °C). Microbial growth was determined every 2 h for 10 h of incubation. Acid tolerance was determined at 0, 5, and 15 min, whereas bile tolerance was analyzed at 0, 4, and 8 h of incubation. Lysozyme tolerance was determined at 0, 1, and 2 h of incubation, while gastric juice tolerance was determined at pH 2, 3, 4, 5, and 7. Protease activity was evaluated at 0, 12, and 24 h incubation. Nipple fruit’s chemical and bioactive compounds were also examined to discuss their impact on the survival of L. acidophilus LA K. Nipple fruit did not affect microbial growth, bile, and acid tolerance. Nipple fruit at 2% had higher survivability on the simulated gastric juice and lysozyme resistance and increased protease activity. Full article

This research aimed to evaluate the effect of the inclusion of Codonopsis pilosula (CP), Illicium verum (IV), Lycium barbarum (LB), and Psidium guajava (PG) water extracts in yogurt (Y) on phenolic antioxidant-linked α-amylase and α -glucosidase inhibitory activities. Four types of herbal yogurt (CP-Y, IV-Y, LB-Y, and PG-Y) and plain-Y (control) were prepared and stored in disposable plastic containers at 4 °C for 28 days. All samples were analysed for peptide concentration using O-phthaldialdehyde, total phenolic content (TPC), 1,1-Diphenyl-2-Picrylhydrazyl radical scavenging activity, and α-amylase and α-glucosidase inhibitory activities (IC₅₀). LB-Y showed the highest peptide concentration and TPC (p < 0.05) among all the yogurts during storage. IV-Y showed the highest (p < 0.05) radical scavenging activity among all herbal yogurts. The best α-amylase and α-glucosidase inhibitory activity (IC₅₀) for all herbal yogurt was on days 7 and 14 of storage. In conclusion, all herbal yogurts could be considered as a potential functional food with antioxidant and anti-diabetic properties. Full article

Bifidobacteria, a major bacterial group, have several beneficial impacts on health, such as enhancing the intestinal flora by limiting the colonization of pathogenic microorganisms and stimulating the immune system. As a result, bifidobacteria have been extensively included in various food products. In this study, Bifidobacterium breve TISTR 2130 was microencapsulated using an emulsion technique with sodium alginate and calcium lactate in green soybean milk as wall materials. This study found that microbeads prepared with 2.0% (w/v) sodium alginate and 2.0% (w/v) calcium lactate had the highest microencapsulation efficiency (MEE) of 99.8% ± 0.07%. In addition, the viability of microencapsulated B. breve TISTR 2130 and free cells was evaluated following a simulated gastrointestinal treatment. Microencapsulated B. breve TISTR 2130 showed higher cell viability than free cells under the simulated gastrointestinal conditions. The viability reduction of free cells dropped substantially to zero after 1 h of incubation in simulated gastrointestinal juice (SIJ), while the viable cell count of microencapsulated B. breve TISTR 2130 remained greater than 5 log CFU/mL and the survival rate was greater than 64% at the end of the sequential digestion. During refrigerated storage of green soybean yogurt (GSY) fortified with microencapsulated B. breve, the viability of B. breve TISTR 2130, syneresis, and acidity decreased, while the pH and viscosity increased. Microencapsulated B. breve TISTR 2130 has the potential to be used as a probiotic fortification in GSY since the viability remained above the recommended minimal limit of 6 log CFU/mL for 10 days during refrigerated storage. The present study demonstrated that the optimized microencapsulated B. breve TISTR 2130 sodium alginate matrix could survive the human gastrointestinal tract to provide health benefits and the possibility of incorporation into functional foods. Full article

In addition to the production of albumin cheese, biogas and whey powder, whey has also been used as a raw material for the production of alcoholic beverages. The aim of this research was to investigate the potential of using Istrian albumin cheese whey in the production of whey distillate. Three batches of Istrian albumin cheese were produced in a small-scale cheese plant. The remaining whey after the production of albumin cheese was fermented using Kluyveromyces marxianus subsp. marxianus for 5 days and then distilled. In the whey samples before and after fermentation, the content of total solids, protein, milk fat and lactose was determined. The ethanol content and the composition of volatile compounds in the distillate was determined. The content of all components of the chemical composition of whey, except for the content of fat, decreased during fermentation. In the whey distillate with an alcohol content of 35%, the following compounds were determined: acetaldehyde, methanol, n-propanol, i-butanol, n-butanol, 3-methyl-1-ol, 2-methylbutan-1-ol and ethyl-lactate. The distillate obtained confirmed the potential of using whey for the production of spirits. However, further research is needed due to the potential presence of the harmful effects of certain volatile compounds on human health. Full article

Soybean has good nutritional and functional properties, which are essential for human physiology. Okara, a residue from soybean processing industries has a distinct profile of nutrients and phytochemicals. Therefore, the current study was planned to investigate the functional importance of okara. In the first phase of this study, okara was isolated from soybean and characterized in terms of protein, fat, ash, soluble dietary fiber, and insoluble dietary fiber. Furthermore, the okara flour was characterized using FT-IR (Fourier transform infrared spectroscopy), and micrograph images were obtained using SEM (scanning electron microscope). In the second phase of study, synbiotic (prebiotics + probiotics) yogurt was prepared with 3% concentrations of okara. Treatments were named as OFY_o (control), OFY₁ (probiotics), and OFY₂ (3% okara + probiotics). Yogurt was subjected to physicochemical, antioxidant, microbiological, and sensory analysis. The addition of okara significantly affected nutritional and antioxidant attributes of yogurt (p < 0.05). The results indicated that adding 3% okara affected the protein, fat, water holding capacity, and color. Total phenolic contents, DPPH (2,2-diphenyl-1-picrylhydrazyl) activity and ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) activity increased due to the addition of okara. Likewise, the highest total viable count (8.25 log CFU/mL) and probiotic count (8.98 log CFU/mL) were noted in yogurt with 3% okara. Okara has dietary fibers; this dietary fiber acts as a prebiotic source for probiotic L. Rhamnosus. This shows that okara has a different prebiotic potential. The addition of okara has promising potential for the development of functional food. Full article

Milk and dairy products are among the most important foods in the human diet. They are natural and culturally accepted and supply the human body with microorganisms that modulate the intestinal microflora. Improper lifestyles, highly processed diets, and certain drugs may contribute to adverse changes in the composition of the gut microflora. These changes may lead to dysbiosis, which is associated with the pathogenesis of many gastrointestinal diseases. This review aims to determine the effect of fermented milk products on the composition of the gut microbiota and their possible support in the treatment of dysbiosis and gastrointestinal diseases. While most research concerns isolated strains of bacteria and their effects on the human body, our research focuses on whole fermented products that contain complex mixtures of bacterial strains. Full article