Acids In Milk Research Articles

Mechanistic modeling of the dynamics of phage attack during milk acidification in the cheese-making process

Bacteriophage attacks represent a major threat in the dairy industry. Here, an unstructured mechanistic model predicting the dynamics of milk acidification in case of phage attack was developed and experimentally validated. Multiple acidification experiments were run with different combinations of initial phage titers and bacterial concentrations and the resulting pH dynamics were recorded. The model could successfully predict the success or failure of milk acidification. Using the model, important biological parameters were deduced from simple, low-cost acidification measurements. These parameters included bacteria’s maximum growth and lysis rates, phages’ burst size, etc. Sensitivity analysis helped identify biologically relevant aspects of phage-host interactions. Growth and lysis kinetics were shown to have the most important impacts. This knowledge can be used to develop easy routine strategies to fight phage attack in the dairy industry. The model can be used to raise awareness amongst cheese makers on the importance of cleaning to avoid food and material waste.

The impact of calcium sequestration on the material and structural properties of acid milk gels and corresponding cream cheeses

SummaryWe report on the role of ethylenediaminetetraacetic acid (EDTA) in addition to the structural and material properties of acid milk gels formed via addition of glucono‐delta‐lactone (GDL) and these properties of corresponding analogue cream cheeses prepared from these gels. Increasing addition of EDTA to cheese milks prior to acidulation reduced the concentration of insoluble calcium in the milks. Acid gelation of milks, as measured by small deformation rheology, showed a decreased rate of gelation and lower relative elastic modulus of gels with increasing EDTA concentration. The sequestration of colloidal calcium phosphate from the casein micelle by the addition of EDTA led to the lower gelation rate and elastic modulus. The lower extent of ionic binding is considered the causative mechanism for formation of weaker gel structures. Cream cheeses prepared using acid gels with GDL acidulant were compositionally unaffected by EDTA concentration. However, variations in G′ observed in the acid gels containing increasing levels of EDTA correlated with large deformation material property changes in cream cheese analogues. In addition, the increasing inclusion of EDTA in cheese milks translated to reduced water‐holding capacity of the cream cheeses prepared from those milks. These results provide insights on the specific role of milk calcium on the structure, material and physical properties of acid milk gels and corresponding cream cheese analogues.

Microbial diversity, aflatoxin M1 contamination and potential lactic acid starters for commercially produced traditional fermented dairy beverages, a case of Bongo from Uganda

This was a cross sectional study that examined the microbial ecology and aflatoxin M1 contamination in commercially produced Bongo, a traditionally fermented dairy beverage from Uganda. It also involved isolation and preliminary evaluation of defined starter cultures for Bongo. Microbial analyses were done by agar plating. Microbial identification was initially done by biochemical testing and microscopy. Followed by 16S rRNA and Internal Transcribed Spacer (ITS) region sequencing for bacteria and yeasts, respectively. Community DNA was studied using Next Generation Sequencing (NGS). Aflatoxin M1 was determined using Ultra High Pressure Liquid Chromatography - Triple Quadrupole Mass Spectrometry. (GTG)5 Rep PCR fingerprinting was used to cluster candidates for starter culture evaluation. The rates of acidification of cow milk by candidate LAB coupled with sensory acceptability of the milk they fermented were the criteria for the selection of the starter cultures. Results indicated that lactic acid bacteria (LAB) and yeasts were the dominant groups. Molds, coliforms, enterococci and staphylococci were also detected. Aflatoxin M1 were insignificant. Based on agar plating technique, lactococci and lactobacilli were dominant, however, NGS showed Streptococci. Agar plating also showed Saccharomyces as dominant, but NGS showed Dipodascus. Cluster analysis identified 18 LAB, which were evaluated for starter culture properties. Three showed promise suggesting that they could be used for commercial production of cultured milks like Bongo.

Extraction of water-soluble polysaccharides from lupin beans and their function of protein dispersion and stabilization under acidic conditions

In the current environment whereby new sources of proteins are extracted from plant material, it is also important to study the potential use of the resulting side streams. Although a number of studies have been conducted on various polysaccharides extracted from plant raw material, a polysaccharide fraction extracted from lupin bean is yet to be explored, in spite of the emerging interest in this crop as a source of food ingredients. In this work lupin soluble polysaccharide (LuPS) was obtained with a recovery as high as 46 % by extraction at pH 8, 120 °C, for 90 min. This fraction, named LuPS-8, was composed of a mostly linear pectic polysaccharide with a weight average molecular mass of 6608 kg/mol, and containing 71.0 % galactose, with minor amounts of arabinose (16.0 %), glucuronic acid 4.6 %, and galacturonic acid 4.1 %. When added to an acid milk dispersion, LuPS-8 improved its dispersibility, providing storage stability against sedimentation over a wider pH range than a HM-pectin reference, between 3.6–4.4. This research demonstrated the potential for upcycling of a side stream of lupin protein production, by the creation of value-added novel functional polysaccharide.

Steady-state modeling of water-splitting and multi-ionic transport of skim milk electro-acidification by bipolar membrane electrodialysis

Electrodialysis has become a relevant technology in promoting sustainability within the food industry. Bipolar membrane electrodialysis offers an efficient and eco-friendly alternative for skim milk acidification, eliminating the need for added acids that affect milk composition and properties. For the first time, this study presents a comprehensive 2-D computational model to investigate the multi-ionic transport and dynamics of skim milk electro-acidification using bipolar membrane electrodialysis. The model is based on conservation equations for mass-charge transport, coupled with the description of water-splitting through the second Wien effect. The primary focus of the analysis was on the skim milk pH evolution and the concentration profiles of the major ions. The results showed that ion concentration values varied due to concentration polarization and differences in ion mobilities. The simulations were compared with experimental data, showing reasonable agreement, particularly for Ca2+ ion concentration. Despite excluding organic components in its analysis, this model offers a novel and valuable approach to the study of skim milk electro-acidification using bipolar membrane electrodialysis, providing essential insights for process understanding and optimization.

Understand and characterize draining of acid milk gels using Magnetic Resonance Imaging and Time Domain-Nuclear Magnetic Resonance

A novel dedicated device is introduced to enable investigation of the filtration draining process of different acid-induced milk gels using Magnetic Resonance Imaging (MRI). This approach allows the spatio-temporal resolution of serum content and distribution in gels throughout draining. Its application for the characterization of five acid gels formulated using reconstituted or fresh milk and using different thermal treatments and/or lactic starters indicates its large potential for a better understanding of acid-induced gel draining in dairy industry. Self-diffusion and relaxation measurements using Time Domain-Nuclear Magnetic Resonance (TD-NMR) were performed on the gels following filtration draining to validate and supplement the MRI results, while gels obtained through centrifugation were examined in view of correlating T2 relaxation times to the water content of gels. The presence of lipids in reconstituted milk or the substitution of a casein fraction by microparticulated denatured whey proteins were shown to impact the structure of gels and their serum holding capacity.

Effect of Shelf Life on Physicochemical and Biochemical Parameters of Camel Milk

Background: Animal feed, environmental conditions and the lactation period are the main factors affecting the composition of camel milk. Methods: In this study, samples from eight (8) camels were collected according to hygiene standards to determine the physico-chemical and biochemical parameters of milk during storage at ambient temperature. pH, titratable acidity, density, total dry matter, ash, fat, protein and vitamin C were determined. Result: The results of the physico-chemical analyses indicate a pH of 5.98±0.30, a titratable acidity of 17.51±1.35°D and a density of 1.01±0.02 after 24 hours of storage at ambient temperature. At the same time, biochemical analyses show an ash content of 7±0.58 g/l, a fat content of 50.09±5.97 g/l and a protein content of 2.31±0.21%. The total dry matter content of camel milk is 129.27±11.31 g/l. The vitamin C content is 41.89±4.51 mg/l. Monitoring of the pH changes of camel milk during storage at room temperature (22±6°C) showed low acidification of camel milk after 24 storage, confirmed by the statistical study which revealed a non-significant difference in pH (p greater than 0.41). While after 24 hours, the differences are significant for pH, dornic acidity and vitamin C content (p less than 0.0001). The remaining ingredients (dry matter, fat, ash) experienced a non-significant progressive decrease (p greater than 0.05). A still non-significant decrease in protein content occurred during the first two days of storage. From the second day, the difference became significant (p less than 0.001). The study of density variation showed a slight non-significant increase (p greater than 0.15) over time. These results have allowed us to confirm that the analyzed camel milk, has a number of particularities in its chemical and physical composition, which prolongs its shelf life.

Novel Probiotic Candidates in Artisanal Feta-Type Kefalonian Cheese: Unveiling a Still-Undisclosed Biodiversity.

Autochthonous dairy lactic acid bacteria (LAB) isolates encompass a natural source of starter, adjunct, or probiotic candidates. In this context, traditionally manufactured, using exclusively animal rennet, Feta-type cheeses were collected from five farms located in different regions of Kefalonia island (Greece). The primary objective of this study was to isolate and characterize novel LAB, thereby exploring the unmapped microbial communities of Kefalonian Feta-type cheese and identifying new potential probiotics. The initial screening, included a preliminary gastrointestinal (GI) tolerance assessment (acidic conditions and bile salts), followed by their safety evaluation (hemolytic activity and antibiotic susceptibility). Based on the preliminary screening, selected strains underwent molecular identification and were further investigated for their probiotic attributes (lysozyme and phenol resistance, antimicrobial traits, antidiabetic aspects, cholesterol reduction and adhesion, adhesion to Caco-2 cells, and milk acidification potential). The results showed that 49, out of the 93 retrieved isolates, exhibited resistance to GI conditions, whereas 18 met the safety criteria. The molecular identification revealed strains belonging to the species Lactiplantibacillus plantarum, Limosilactobacillus fermentum, Lacticaseibacillus rhamnosus, and Lacticaseibacillus paracasei. The selected rod-shaped 14 isolates displayed a potential probiotic character. The best-performing isolates concerning cholesterol assimilation and adhesion, α-glucosidase inhibition, and epithelial adherence were Lpb. plantarum F89, F162, and F254 and Lcb. paracasei F214 and F216, whereas Lcb. paracasei F70 showed potential as a defined strain starter. The present study explores for the first time the biodiversity of traditionally fermented microbial communities in Kefalonian Feta-type cheese, revealing novel potential probiotic strains that can contribute to the development of innovative functional food products.

A multifaceted investigation of lactococcal strain diversity in undefined mesophilic starter cultures.

This study reports on the development of a combined culture-based analysis and metagenomics approach to evaluate the composition of two undefined mesophilic starter cultures. In addition, a novel qPCR-based genotype detection assay, capable of discerning nine distinct lactococcal genotypes (based on lactococcal cell wall polysaccharide biosynthesis gene clusters), was used to monitor compositional changes in an undefined starter culture following phage attack. These analytical approaches facilitate a multifaceted assessment of starter culture compositional stability during milk fermentation, which has become an important QC aspect due to the increasing demand for consistent and high-quality dairy products.

The effect of seed germination and Bacillus spp. on the ripening of plant cheese analogs.

The development of novel plant-based fermented food products for which no traditional templates exist requires the development of starter cultures. Although the principles of microbial flavor formation in plant-based analogs partially overlap with dairy fermentations, the composition of the raw materials and thus likely the selective pressure on the activity of starter cultures differs. Experiments that are described in this study explored the use of seed germination, the use of lactic acid bacteria, and the use of bacilli to reduce hygienic risks, to acidify plant milk, and to generate taste-active compounds through proteolysis and fermentative conversion of carbohydrates. The characterization of fermentation microbiota by culture-dependent and culture-independent methods also confirmed that the starter cultures used were able to control microbial communities throughout 90 d of ripening. Taken together, the results provide novel tools for the development of plant-based analogs of fermented dairy products.

Functional properties of cream and butter oil from milk of Holstein cows abomasally infused with increasing amounts of high-oleic sunflower fatty acids.

This research paper addresses the hypothesis that there is an optimal amount of intestinally available oleic acid (provided via abomasal infusion) to produce higher-oleic acid milk fat with satisfactory functional characteristics of cream and butter oil. A control and four increasing doses of free fatty acids from high oleic sunflower oil (HOSFA) were infused into the abomasum of four lactating dairy cows in a crossover experimental design with 7-d periods. Treatments were: (1) control (no HOSFA infused), (2) HOSFA (250 g/d), (3) HOSFA (500 g/d), (4) HOSFA (750 g/d), and (5) HOSFA (1000 g/d). All treatments included meat solubles and Tween 80 as emulsifiers. Viscosity, overrun and whipping time as well as foam firmness and stability were evaluated in whipping creams (33% fat). Solid fat content (from 0 to 40°C), melting point and firmness were determined in butter oil. Whipping time of cream increased linearly and viscosity decreased linearly as infusion of HOSFA increased. Overrun displayed a quadratic response, decreasing when 500 g/d or more was infused. Foam firmness and stability were not affected significantly by HOSFA. For butter oil, melting point, firmness, and solid fat content decreased as HOSFA infusion increased. Changes in 21 TG fractions were statistically correlated to functional properties, with 6-10 fractions showing the highest correlations consistently. Decisions on the optimal amount of HOSFA were dependent on the dairy product to which milk fat is applied. For products handled at commercial refrigeration temperatures, such as whipping cream and butter oil, the 250 g/d level was the limit to maintain satisfactory functional qualities. Palmitic acid needed to be present in at least 20% in milk fat to keep the functional properties for the products.

Application of bipolar membrane electrodialysis for acidification of skim milk. A comprehensive study on process performance and effects on ion-exchange membranes

Bipolar membrane electrodialysis (EDBM) can be applied for the electro-acidification of skim milk (SM) using a water-splitting effect. A new method of SM acidification gives opportunities and perspectives to the development of alternative and novel products in the dairy industry. The present study assessed the effect of temperatures from 5 °C to 30 °C of EDBM on the electro-acidification of SM in terms of the mineral composition of the side streams. The mechanisms of ion transport during electro-acidification by bipolar membranes (BMs) coupled with cation-exchange membranes (CMs) were investigated. The results showed that the pH of the SM was decreased by ∼14.3% through the proton ions generated due to a water-splitting reaction in the bipolar interface region. Since the BMs and CMs are suspected to change their properties at different temperatures in the high protein solution, their properties and characteristics were investigated. The EDBM performance parameters were calculated. Furthermore, performance efficiency coefficients of the EDBM process as mass flux (J), capacity (CF), specific energy consumption (E) and the current efficiency (η) were calculated.

Role of Clay Substrate Molecular Interactions in Some Dairy Technology Applications.

The use of clay materials in dairy technology requires a multidisciplinary approach that allows correlating clay efficiency in the targeted application to its interactions with milk components. For profitability reasons, natural clays and clay minerals can be used as low-cost and harmless food-compatible materials for improving key processes such as fermentation and coagulation. Under chemical stability conditions, clay materials can act as adsorbents, since anionic clay minerals such as hydrotalcite already showed effectiveness in the continuous removal of lactic acid via in situ anion exchange during fermentation and ex situ regeneration by ozone. Raw and modified bentonites and smectites have also been used as adsorbents in aflatoxin retention and as acidic species in milk acidification and coagulation. Aflatoxins and organophilic milk components, particularly non-charged caseins around their isoelectric points, are expected to display high affinity towards high silica regions on the clay surface. Here, clay interactions with milk components are key factors that govern adsorption and surface physicochemical processes. Knowledge about these interactions and changes in clay behavior according to the pH and chemical composition of the liquid media and, more importantly, clay chemical stability is an essential requirement for understanding process improvements in dairy technology, both upstream and downstream of milk production. The present paper provides a comprehensive review with deep analysis and synthesis of the main findings of studies in this area. This may be greatly useful for mastering milk processing efficiency and envisaging new prospects in dairy technology.

Treatment of milk with various chemicals differentially affects the physicochemical and functional characteristics of extracellular vesicles

Isolation of high-purity milk-derived extracellular vesicles (miEV) is complicated by protein impurities, such as casein. The focus of this study was to investigate whether the treatment of milk with acetic acid (AA), ethylenediaminetetraacetic acid (EDTA), and sodium citrate (SC), which are known chemicals to deplete caseins from miEV, alters their physicochemical and functional characteristics differently. For this purpose, following the treatment of milk with AA, EDTA, and SC, various subpopulations (12 K, 35 K, 70 K, and 100 K) of miEV were isolated by differential ultracentrifugation and characterized by protein quantification assay, gel electrophoresis, western blotting, dynamic light scattering, and scanning electron microscopy. In addition, the cellular uptake and immunomodulatory potential of miEV were also assessed. The results indicated that protein impurities, including caseins, were differentially depleted from miEV subpopulations by AA, EDTA, and SC. However, the acidification of milk induced partial protein aggregation. Additionally, miEV from both AA- and EDTA-treated milk exhibited a less smooth surface and higher uptake compared to those from SC-treated milk. Although all miEV significantly reduced T cell proliferation, a higher immunomodulatory potential was found in miEV from AA-treated milk. In conclusion, AA, SC, and EDTA have different efficiencies in improving the purity of miEV and can affect their physicochemical and functional characteristics differently. This issue may be critical for the efficient isolation of pure subpopulations of miEV for biomedical research.

A review of fermented milks: potential beneficial effects on human nutrition and health.

Fermented dairy products are formed during the acidification of milk through fermentation by suitable microorganisms; it contains different microorganisms in sufficient numbers and in an active state. A wide range of fermented milk products are produced and consumed around the world, including yogurt, kefir, koumiss, and yogurt beverages. There are various health benefits associated with the consumption of fermented dairy. Many studies reported that some fermented milk products have antimicrobial, antimutagenic, anticarcinogenic, and antihypertensive properties as well as provide benefits on mineral metabolism, reduce lactose intolerance symptoms and cholesterol levels. In addition to these effects, it has many other beneficial effects such as positive effects on type 2 diabetes and hypertension, antimutagen and antioxidant effects, and reduction of allergic symptoms. Dairy products including fermented milk are known to be the main carrier of probiotic microorganisms, and many clinical studies show the effects of probiotic strains on health. In this study, the effects of fermented milks on human nutrition and health are mentioned.

The impact of Kakadu Plum (Terminalia ferdinandiana) fruit powder and its pectic oligosaccharides on the growth, survival and antimicrobial activity of probiotic bacteria in milk.

Prebiotics are essential for improving the growth and survival of probiotics in products, which leads to maintaining the balance of the gut microbiome for overall health. Therefore, the aim of this study was to develop a novel source of prebiotic from an Australian native fruit Terminalia ferdinandiana (Kakadu plum [KP]) and its pectic oligosaccharide (POS) extract by studying their prebiotic effect on growth, survival and milk acidification of six probiotic bacteria. Lactococcus lactis 537, Lactobacillus acidophilus ATCC 4356, Lactobacillus plantarum 299v, Lactobacillus rhamnosus GG, Lactobacillus reuteri ATCC 55730 and Lactobacillus casei ATCC 393 were cultured in skim milk containing 1% and 3% of KP, or 1% of POS derived from KP pectin or apple pectin. Based on the results, the stimulation effect of KP and KP POS on bacteria growth and acidification of milk was found to be species-dependent. A higher prebiotic potential was shown by 1% KP for most strains, while 3% KP significantly enhanced the antimicrobial activity of nisin-producing Lc. lactis 537 supernatant against Staphylococcus aureus. KP POS was more effective than KP in assisting probiotic survival during storage over 14 days at 4 °C and maintaining the pH value of milk of 6 or above during fermentation. Analysis of the monosaccharides and uronic acids of POS from KP revealed mostly glucose, fructose, galactose, arabinose and galacturonic acid. The KP and its POS could be classified as novel prebiotics which support improved growth, survival and antimicrobial activity of specific probiotic bacteria, and areas for future research are recommended.

Technological potential of native lactic acid bacteria isolated from Swiss-type artisanal cheese (Ancash, Peru) for their application in food

Swiss-type artisanal cheese is highly appreciated sensorially, its flavor is often associated with the lactic acid bacteria involved in its production, which in many cases are indigenous. Three artisanal Swiss-type cheeses of greatest preference in the market of Huaraz (Ancash) were selected. The main LAB were isolated and identified and their safety properties and technological potential for their application in new cheeses were verified in vitro and evaluated by consumers. Eleven strains were confirmed as LAB by Gram-positive and catalase-negative biochemical tests; according to 16S rDNA, seven strains belonged to Lacticaseibacillus paracasei (KQ3, EQ1, CQ1, YQ1, LQ2, GQ2 and TQ1), three strains to Lentilactobacillus parabuchneri (BQ2, OQ2 and RQ3), and one to Lactiplantibacillus sp. (QQ3). In safety assays, LAB did not exhibit gelatinase or hemolytic activities. In addition, L. paracasei KQ3, GQ2 and L. parabuchneri BQ2 effectively inhibited pathogens such as S. aureus, E. coli and L. monocytogenes. Antibiotic susceptibility was variable among strains. L. paracasei CQ1, EQ1, KQ3, TQ1 and Lactiplantibacillus sp. QQ3 showed high milk acidification capacity (0.16-1.44%) and reduced pH from 6.6 to 3.5 after 72 h of incubation. L. paracasei CQ1, Lactiplantibacillus sp. QQ3 and L. paracasei KQ3 showed the highest casein degradation zones (20.8-11.5 mm). All strains showed lipolytic activity, with Lactiplantibacillus sp. QQ3, L. paracasei CQ1 and L. parabuchneri BQ2 standing out with halos of 30.8-36.3 mm. Lactiplantibacillus sp. QQ3 and L. paracasei TQ1 showed ability to produce diacetyl. The best strains were tested in cheese production where L. paracasei CQ1 showed the best sensory qualities. Finally, the native BAL strains showed a high potential for the production of natural, safe and sensorially acceptable dairy products.

Lactic acid bacteria from artisanal raw goat milk cheeses: technological properties and antimicrobial potential.

In cheese-making, a starter culture composed of adequately chosen lactic acid bacteria (LAB) may be suitable to ensure the rapid acidification of milk, improve textural and sensory characteristics, and avoid pathogen proliferation. In this work, 232 LAB isolates collected from artisanal goat's raw milk cheeses produced in Portugal were evaluated for their antimicrobial capacity (at 10 and 37°C), as well as their acidifying and proteolytic properties. Among the 232 isolates, at least 98% of those isolated in De Man- Rogosa-Sharpe (MRS) agar presented antagonism against Listeria monocytogenes, Salmonella Typhimurium, or Staphylococcus aureus, whereas less than 28.1% of M17-isolated LAB showed antagonism against these pathogens. M17-isolated LAB displayed better results than MRS ones in terms of acidifying capacity. As for the proteolytic assay, only 2 MRS isolates showed casein hydrolysis capacity. Principal component analyses and molecular characterization of a subset of selected isolates were conducted to identify those with promising capacities and to correlate the identified LAB genera and species with their antimicrobial, acidifying, and/or proteolytic properties. Lactococcus strains were associated with the highest acidifying capacity, whereas Leuconostoc and Lacticaseibacillus strains were more related to antimicrobial capacities. Leuconostoc mesenteroides, Lactococcus lactis, and Lacticaseibacillus paracasei were the predominant organisms found. The results of this work highlight various strains with pathogen inhibition capacity and suitable technological properties to be included in a customized starter culture. In future work, it is necessary to appropriately define the starter culture and implement it in the cheese-making process to evaluate if the in-vitro capacities are observable in a real food system.

Impact of ultrasound-assisted fermentation on buffalo yogurt production: Effect on fermentation kinetic and on physicochemical, rheological, and structural characteristics

This work evaluated the buffalo milk acidification kinetics using partially or fully ultrasound-assisted fermentation and yogurt characteristics without or with sugar (5%). The results showed that assisted fermentation in an ultrasonic bath (25 kHz, 38 W/L) accelerates the fermentation rate (up to 41% increase), reducing the fermentation time (up to 2 h), and, in some conditions, improved the yogurt quality. Samples produced by US-assisted fermentation under 1 or 2 h had higher water holding capacity (up to 35%), consistency index (up to 423%), and apparent viscosity (up to 246%), explained by the formation of a stronger gel, as elucidated by microscopy images. In contrast, no differences in pH, acidity, and lactic acid bacteria viability were observed. Additionally, sucrose contributed positively to the yogurt quality, improving gel formation. Therefore, buffalo milk fermentation under US (up to 2 h) is an interesting strategy that accelerates fermentation and improves the buffalo yogurt quality.

Exploring the Possibility of Enriching Fermented Milks with Young Barley Leaves Powder Preparation

Barley (Hordeum vulgare L.) is one of the first cereals that humans began to cultivate. This study aimed to investigate the possibility of enriching fermented dairy products, using fermented milk as an example, with young barley leaves powder (YBLP) preparation including different starter cultures of lactic acid bacteria (LAB). The addition of YBLP did not affect the maximum rate of acidification and the time at which the maximum acidification rate was achieved. However, it did impact the time required to reach the desired pH level (4.6) for specific starter cultures. Over a 28-day storage period, gradual acidification of the fermented milk was observed. The addition of YBLP has a limited effect on the pH of the fermented milk, with the pH value primarily dependent on the type of starter culture and storage time. The addition of YBLP may have a positive effect on the survival of bacterial cells during the storage of the fermented milk; however, a gradual decrease in the number of LAB cells was observed during refrigerated storage. Furthermore, the addition of YBLP had a significant effect on the hardness, adhesion, and water-holding capacity of some fermented milk immediately after fermentation, depending on the specific starter culture used.