Viscosity of model yogurt systems enriched with barley β-glucan as influenced by starter cultures

The effect of barley β-glucan (BG) on the growth of two yogurt starter cultures (SCs) each consisting of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus was investigated. Model yogurt systems were prepared with or without the incorporation of barley BG and lactose to mimic natural levels in milk and allowed to ferment for 8 h at 42 °C. The fermentation efficacy of the SCs was monitored through pH measurements. Samples were collected and analyzed for pH and viscosity at 0, 2, 4, and 8 h. Viscosity was determined using a rotational viscometer at shear rates of 1.29–129 s⁻¹ and 20 °C. The pH measurements indicated no adverse effect on the growth of SCs as the acidification process was consistent with normal pH development, but viscosity measurements suggested that BG was depolymerized by SCs when lactose became a limiting nutrient during fermentation.     

Use of Galactose-Fermenting Streptococcus thermophilus in the Manufacture of Swiss,Mozzarella, and Short-Method Cheddar Cheese

Galactose-fermenting (galactose-positive) strains of Streptococcus thermophilus, alone and combined with galactose-positive and galactose-negative strains of Lactobacillus bulgaricus, were used as starter cultures in the manufacture of Swiss and Mozzarella cheese and were paired with Streptococcus lactis (also galactose-positive) in short-method Cheddar cheese manufacture. Experimental Swiss cheese made with the galactose-positive Streptococcus thermophilus starter alone contained a large amount of galactose (ca. 26 to 28 µmol/g of curd) 28 h after hooping compared with control Swiss (< 2 µmol/g) made with a nongalactose fermenting strain of Streptococcus thermophilus and a galactose-positive strain of Lactobacillus bulgaricus. Mozzarella and short-method Cheddar made with only galactose-positive Streptococcus thermophilus also contained large amounts of galactose. Swiss cheese made with a galactose-positive strain of Streptococcus thermophilus and a galactose-negative strain of Lactobacillus bulgaricus had little galactose remaining after 28 h, indicating that the Lactobacillus had a stimulatory effect on galactose metabolism in Streptococcus thermophilus. These results indicate that galactose-fermenting Streptococcus thermophilus may have limited potential when used as single strain starter cultures in Swiss cheese, but may be useful when combined with galactose-positive Lactobacillus in the manufacture of Mozzarella cheese.     

Effect of lactose hydrolysis on the milk-fermenting properties of Lactobacillus delbrueckii ssp. bulgaricus 2038 and Streptococcus thermophilus 1131

Yogurt is a well-known nutritious and probiotic food and is traditionally fermented from milk using the symbiotic starter culture of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. However, yogurt consumption may cause health problems in lactose-intolerant individuals, and the demand for lactose-free yogurt has been increasing. The standard method to prepare lactose-free yogurt is to hydrolyze milk by lactase; however, this process has been reported to influence the fermentation properties of starter strains. This study aimed to investigate the fermentation properties of an industrial starter culture of L. bulgaricus 2038 and S. thermophilus 1131 in lactose-hydrolyzed milk and to examine the metabolic changes induced by glucose utilization. We found that the cell number of L. bulgaricus 2038, exopolysaccharide concentration, and viscosity in the coculture of L. bulgaricus 2038 and S. thermophilus 1131 was significantly increased in lactose-hydrolyzed milk compared with that in unhydrolyzed milk. Although the cell number of S. thermophilus 1131 showed no difference, production of formic acid and reduction of dissolved oxygen were enhanced in lactose-hydrolyzed milk. Further, in lactose-hydrolyzed milk, S. thermophilus 1131 was found to have increased the expression of NADH oxidase, which is responsible for oxygen reduction. These results indicated that glucose utilization promoted S. thermophilus 1131 to rapidly reduce the dissolved oxygen amount and produce a high concentration of formic acid, presumably resulting in the increased cell number of L. bulgaricus 2038 in the coculture. Our study provides basic information on the metabolic changes in starter strains in lactose-hydrolyzed milk, and demonstrates that lactose-free yogurt with increased cell number of L. bulgaricus can be prepared without delay in fermentation and decrease in the cell number of S. thermophilus.     

Enhancement of flavour development in ras cheese made by direct acidification

An attempt has been made to enhance flavour development in Ras cheese made from directly acidified milk. Addition of a ripened cheese slurry, yoghurt culture (Streptococcus thermophilus + Lactobacillus bulgaricus) or cheese starter (S. lactis + L. casei + Leuconostoc citrovorum) to the chemically acidified curd enhanced flavour intensity, body characteristics, the formation of both soluble nitrogen compounds and Free Fatty Acids and stimulated bacterial growth. Sensory properties (or characteristics) of cheese from chemically acidified curd incorporating the above additives approached those of control cheese.     

Identification of cultivable lactic acid bacteria isolated from Algerian raw goat's milk and evaluation of their technological properties

One hundred and fifty-eight strains of lactic acid bacteria isolated from Algerian raw goat's milk were identified and technologically characterized. Five genera were found: Lactobacillus (50.63%), Lactococcus (25.94%), Streptococcus (14.56%), Leuconostoc (7.59%) and Pediococcus (1.26%). The predominant species were Lactococcus lactis (32 strains), Streptococcus thermophilus (23 strains), Lactobacillus bulgaricus (19 strains), Lb. helveticus (16 strains) and Lb. plantarum (14 strains).Approximately 39% of the lactic acid bacteria isolated produced more than 0.6% lactic acid (w/v) after 18 h of incubation, and belonged to the Lactococcus and Lactobacillus genera. The highest proteolytic activity was approximately 3 mg tyrosine l⁻¹ for mesophilic strains and nearly 5 mg tyrosine l⁻¹ for thermophilic lactobacilli after 72 h. High aromatic activity (more than 0.8 mg diacetyl l⁻¹ after 16 h) was detected in 14% of the strains.Nine strains were used to make dairy products (a yoghurt-like product and Edam-type cheese) on a pilot scale in the laboratory. The best-liked organoleptic characteristics were noted in a yoghurt produced with a mixed culture made up of S. thermophilus (strain 16TMC+) and Lb. helveticus (strain 20TMC) and in a cheese made with a starter composed of Lc. lactis subsp. lactis (strain 10MCM) and L. lactis subsp. lactis (V.P. +) (strain 19MCM).     

Production of volatile aroma compounds by kefir starter cultures

Production of carbonyl compounds by single-strain cultures, kefir starter (Lactobacillus delbrueckii subsp. bulgaricus HP1+Lb. helveticus MP12+Lactococcus lactis subsp. lactis C15+Streptococcus thermophilus T15+Saccharomyces cerevisiae A13) and kefir grains during fermentation and storage of kefir was studied. The content of carbonyl compounds produced by kefir starter was greater than that produced by kefir grains. The maximum acetaldehyde concentration (18.3 μg g⁻¹) in kefir with starter culture was mainly due to the metabolic activity of Lb. delbrueckii subsp. bulgaricus HP1 isolated from kefir grains. The highest diacetyl production activity was recorded in the starter culture (1.87 μg g⁻¹) and the single-strain culture St. thermophilus T15 (1.62 μg g⁻¹), followed by Lb. helveticus MP12 (0.85 μg g⁻¹) and Lc. lactis subsp. lactis C15 (0.42 μg g⁻¹). The lactobacilli Lb. delbrueckii subsp. bulgaricus HP1 and Lb. helveticus MP12 produced acetone, which was not found in the cocci cultures. The presence of 2-butanone was related to the production ability of Lb. helveticus MP12. In comparison, Lc. lactis subsp. lactis C15 synthesized ethyl acetate more actively than the other single-strain cultures included in the starter. S. cerevisiae A13 produced ethanol and CO₂ in amounts (3975 μg g⁻¹; 1.80 g L⁻¹) that lent cultured kefir distinctive flavour and aroma characteristic of authentic kefir.     

High hydrostatic pressure processing on microstructure of probiotic low-fat yogurt

The effect of milk processing on the microstructure of probiotic low-fat yogurt was studied. Skim milk fortified with skim milk powder was subjected to three treatments prior to innoculation: thermal treatment at 85 °C for 30 min, high hydrostatic pressure at 676 MPa for 5 min, and combined treatments of high hydrostatic pressure (HHP) and heat. The processed milk was then fermented by using two different starter cultures containing Streptococcus thermophilus, Lactobacillus delbrueckii ssp. bulgaricus, Lactobacillus acidophilus, and Bifidobacterium longum. The microstructure of heat-treated milk yogurt had fewer interconnected chains of irregularly shaped casein micelles, forming a network that enclosed the void spaces. On the other hand, microstructure of HHP yogurt had more interconnected clusters of densely aggregated protein of reduced particle size, with an appearance more spherical in shape, exhibiting a smoother more regular surface and presenting more uniform size distribution. The combined HHP and heat milk treatments led to compact yogurt gels with increasingly larger casein micelle clusters interspaced by void spaces, and exhibited a high degree of cross-linking. The rounded micelles tended to fuse and form small irregular aggregates in association with clumps of dense amorphous material, which resulted in improved gel texture and viscosity.     

Quantitative Changes in Oligosaccharides During Fermentation and Storage of Yogurt Inoculated Simultaneously with Starter Culture and β-Galactosidase Preparation

Low lactose yogurt was manufactured by simultaneous inoculation with β-galactosidase of Aspergillus oryzae from two commercial sources and yogurt starter culture. Addition of 4.7 units enzyme/100 ml resulted in 64 and 58% depletion of the lactose by the two enzyme preparations compared with 35% in control yogurt at 8 h. Lactose was completely hydrolyzed with 93 units enzyme/100 ml in the same period. With 4.7 units/100 ml from our preparation, the oligosaccharide percentage reached its maximum value of 15% of the total sugar in 2 h, slightly decreased to 12% after 8 h, and was 7% after 10 d storage at 5°C. The oligosaccharide percentage with 4.7 units/100 ml from the other preparation was 4 to 8% of the total sugar during fermentation and storage. The oligosaccharide content in low lactose yogurt was 4 to 19 times higher than that obtained with the control yogurt (.3 to 1.7%).     

Short communication: Lactose enhances bile tolerance of yogurt culture bacteria

Lactose is an energy source for culture bacteria. Bile tolerance is an important probiotic property. Our aim was to elucidate the effect of lactose on bile tolerance of yogurt starter culture Lactobacillus bulgaricus LB-12 and Streptococcus thermophilus ST-M5. Bile tolerance of pure cultures was determined using 0.3% oxgall in MRS THIO broth (Difco, Becton Dickinson, Sparks, MD) for L. bulgaricus and 0.3% oxgall in M17 broth (Oxoid, Basingstoke, UK) for Strep. thermophilus. Lactose was added to both broths at 0 (control), 1, 3, and 5% (wt/vol) broth. Dilutions were plated hourly for 12 h. Experiments were replicated 3 times. At 2, 4, and 12 h of incubation, lactose incorporated at all amounts, 1, 3, and 5% (wt/vol), showed higher counts of Strep. thermophilus ST-M5 compared with the control. Lactose use at 5% (wt/vol) significantly enhanced bile tolerance of both L. bulgaricus and Strep. thermophilus compared with control.     

Immunomodulatory effects of polysaccharides produced by Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1

The extracellular polysaccharides (EPS) produced by lactic acid bacteria (LAB) are associated with the rheology, texture, and mouthfeel of fermented milk products, including yogurt. This study investigated the immunomodulatory effects of EPS purified from the culture supernatant of Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) OLL1073R-1. The crude EPS were prepared from the culture supernatant of L. bulgaricus OLL1073R-1 by standard chromatographic methods, and were fractionated into neutral EPS and acidic EPS (APS). Acidic EPS were further fractionated into high molecular weight APS (H-APS) and low molecular weight APS (L-APS). High molecular weight APS were shown to be phosphopolysaccharides containing D-glucose, D-galactose, and phosphorus. Stimulation of mouse splenocytes by H-APS significantly increased interferon-γ production, and, moreover, orally administered H-APS augmented natural killer cell activity. Oral administration of yogurt fermented with L. bulgaricus OLL1073R-1 and Streptococcus thermophilus OLS3059 to mice showed a similar level of immunomodulation as H-APS. However, these effects were not detected following administration of yogurt fermented with the starter combination of L. bulgaricus OLL1256 and S. thermophilus OLS3295. We conclude from these findings that yogurt fermented with L. bulgaricus OLL1073R-1, containing immunostimulative EPS, would have an immunomodulatory effect on the human body.     

Nonenzymatic Browning of Mozzarella Cheese

Mozzarella cheese was made with combinations of Streptococcus thermophilus nongalactose (Gal^?) and galactose fermenting (Gal⁺) strains and Lactobacillus helveticus (Gal⁺) and L. bulgaricus (Gal^?). Galactose was found in all Mozzarella cheese regardless of the culture used. The highest concentration was in cheese made with Streptococcus thermophilus Gal^?L. bulgaricus Gal^? combination with Streptococcus thermophilus Gal⁺Lactobacillus helveticus Gal⁺ having the least. Little if any lactose was found in any of the cheeses. The temperature and time during stretching of the curd inhibited fermentation of the residual galactose.Galactose accumulated in Mozzarella when either strain of Streptococcus thermophilus was used. The fermentation of accumulated galactose was the result of metabolism by Lactobacillus helveticus. There was a positive correlation between galactose content and brown color intensity when Mozzarella cheese was heated. A predictive test was effective in evaluating the browning tendency of cheese.     

Probiotic stability of yoghurts containing Jerusalem artichoke inulins during refrigerated storage

Experimentally prepared Jerusalem artichoke inulins (JAI) were compared with two commercial chicory root inulins for their prebiotic potentials in media broth model and growth-sustaining ability in non-fat yoghurts. Experimental yoghurts were made with 12% reconstituted skim milk (RSM) supplemented with 4% inulin powders, inoculated with mixed cultures of Lactobacillus casei LC-01, Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus (1:0.5:0.5 based on supplier’s recommendation) and incubated overnight at 37 °C. Non-supplemented yoghurt was prepared from 16% RSM and used as control. The survival and acidifying activity of lactic and probiotic cultures in all yoghurts were investigated on weekly intervals during the shelf life of 28 days at 4 °C. Incorporation of JAI resulted in improved viability of LC-01, maintaining >7.0 log CFU/g during cold storage but did not affect the viability of yoghurt bacteria in comparison with the control.     

Growth of Lactobacillus bulgaricus in Milk. 1. Cell Elongation and the Role of Formic Acid in Boiled Milk

An abnormal elongation of cells occurred when Lactobacillus bulgaricus B5b was cultivated in milk heated at 100°C for 15 min. Nuclear staining revealed that the elongated cells were multinucleate, and septum staining indicated that the septum had not yet formed. Similar cell elongation was confirmed using other strains of L. bulgaricus.Extent of cell elongation varied with strains and heating conditions of milk; severe heating shortened the cell length. This cell elongation was not observed in autoclaved milk (121°C, 15 min), milk containing added formic acid and heated to 100°C for 15 min, and in mixed culture with Streptococcus thermophilus. The formate added to the milk was incorporated into purines of ribonucleic acid and deoxyribonucleic acid of the cells. Addition of formic acid or adenine stimulated ribonucleic acid synthesis in the cells cultivated in milk heated to 100°C for 15 min. The cell elongation was always accompanied by a remarkable depression of ribonucleic acid synthesis.Lactobacillus bulgaricus cells grown in milk heated to 100°C for 15 min are not able to produce adequate amounts of formic acid required for synthesis of purines de novo.     

Identification and technological properties of lactic acid bacteria isolated from raw goat milk of four Algerian races

The characteristics of 725 lactic acid bacteria isolated from raw goat milk of four Algerian races were studied. They were phenotypically classified as Lactobacillus (31.6%), Lactococcus (28.4%), Leuconostoc (22.2%), Streptococcus (13.7%) and Pediococcus (4.1%). No major differences were observed as to the distribution of genus isolates in the milk of three races (Makatia, Makatia-Chamia and Kabyle). However, the number of isolates of both Leuconostoc and Lactococcus predominated in Arabia milk while the samples collected from the other races mostly contained lactobacilli isolates.The phenotypic and biochemical analyses gave a diversity of species (28 presumptive species). The most abundant species were Streptococcus thermophilus (46 isolates), Lactobacillus helveticus (45 isolates), Lactobacillus plantarum (30 isolates), Lactobacillus delbruecki subsp. bulgaricus (26 isolates), Lactobacillus brevis (25 isolates) and Lactococcus lactis subsp. lactis (25 isolates).The technological properties of the isolates were as follows: 38.6% of isolates showed a fast acidifying rate (more than 60°D during 18 h of incubation); 25.9% of isolates had a high proteolytic capacity (more than 6 ppm leucine/72 h) and 14.1% of isolates had a high diacetyl production (more than 0.8 ppm diacetyl/16 h).Nine isolates were selected to prepare yoghurt and cheese. Sensory tests performed by a trained panel revealed a pleasant yoghurt prepared with mixed culture St. thermophilus 16 TMC+L. helveticus 20TMC. Cheese prepared with isolates L. lactis subsp. lactis biovar diacetylactis 19 MCA and L. lactis subsp. lactis 10 MCM had a very good sensory quality and a pleasant taste.     

Dual-enzymatic synthesis of lactulose in organic-aqueous two-phase media

Lactulose has been successfully synthesized by dual-enzymatic method in organic-aqueous two-phase media using lactose and fructose as the raw materials. Cyclohexane–buffer system C₆H₁₂:buffer = 95:5 (v/v) was employed as the organic-aqueous media for the reaction. The dual-enzymatic system was consisted of immobilized lactase (IL) and immobilized glucose isomerase (IGI). Immobilized lactase was prepared by cross-linking the free lactase into Fe₃O₄-chitosan magnetic microspheres. The main enzymatic reaction parameters were investigated, including reaction temperature (T), pH value and reaction time (t). Under the optimum reaction conditions, i.e., lactose 0.8 g mL^?1, fructose 0.1 g mL^?1, IL 0.1 g mL^?1, IGI 0.05 g mL^?1, T = 30 °C, pH = 8.0 and t = 2 h, the obtained highest lactulose yield was approximately 151 g L^?1 and the corresponding productivity was 75.5 g L^?1 h^?1. Experimental results indicated that the organic-aqueous media can significantly promoted the transglycosidation activity of lactase and therefore improve the lactulose yield. The possible reaction mechanism of the synthesis of lactulose using IL and IGI in two-phase system was also proposed.     

Short communication: Influence of an aqueous myrrh suspension on yogurt culture bacteria over yogurt shelf life

Myrrh is an essential oil and natural flavoring approved by the US Food and Drug Administration, and it has antibacterial and antifungal activity against pathogens. Our objective was to determine the effect of an aqueous myrrh suspension on Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus counts in peptone solution and yogurt, as well as pH and titratable acidity of yogurt during 5 wk of storage at 1 to 4°C. The myrrh suspension (10% wt/vol) was prepared and incorporated into a pure culture dilution in peptone and into yogurt mix at a 1% (vol/vol) level. A control with no myrrh was also prepared, and 3 replications were conducted. Streptococcus thermophilus were enumerated using Streptococcus thermophilus agar with aerobic incubation at 37°C for 24 h, and Lactobacillus delbrueckii ssp. bulgaricus were enumerated using de Man, Rogosa, and Sharpe agar adjusted to pH 5.2, with anaerobic incubation at 43°C for 72 h. During the 8-h period after inoculation, S. thermophilus and L. delbrueckii ssp. bulgaricus counts in peptone solution at 37°C and 43°C, respectively, were not significantly different in the presence or absence of the aqueous myrrh suspension. Counts of S. thermophilus in yogurt containing myrrh (mean ± SD; 4.96 ± 0.58 log cfu/mL) were not significantly different from those in the control yogurt (4.87 ± 0.39 log cfu/mL). The log counts for L. delbrueckii ssp. bulgaricus in yogurt containing myrrh (5.04 ± 1.44 log cfu/mL) and those of the control (5.52 ± 1.81 log cfu/mL) did not differ, and the counts remained within 1 log of each other throughout 5 wk of storage. The pH of the yogurts containing the aqueous myrrh suspension was not significantly different from that of the control yogurts, and their pH values were within 0.1 pH unit of each other in any given week. Titratable acidity values remained steady around 1.1 to 1.2% lactic acid for both yogurt types throughout the storage period, with no significant differences between them. Yogurt culture bacteria can survive in the presence of a myrrh suspension in yogurt with no significant change in pH or titratable acidity. Therefore, it may be beneficial to add an aqueous myrrh suspension to yogurt.     

Effect of acidification on the activity of probiotics in yoghurt during cold storage

The viability of Lactobacillus acidophilus LAFTI^® L10, Bifidobacterium lactis LAFTI^® B94, and L. paracasei LAFTI^® L26 and their proteolytic activities were assessed in yoghurt at different termination pH of 4.45, 4.50, 4.55, and 4.60 in the presence of L. delbrueckii ssp. bulgaricus Lb1466 and Streptococcus thermophilus St1342 during 28 days of storage at 4 °C. All strains achieved the recommended level of 6.00 log cfu g⁻¹ of the product with L. acidophilus LAFTI^® L10 and L. paracasei LAFTI^® L26 exceeding the number to 8.00 and 7.00 log cfu g⁻¹, respectively. Lactobacilli strains showed a good cellular stability maintaining constant concentration throughout storage period regardless of termination pH. On the other hand, the cell counts of B. lactis LAFTI^® B94 decreased by one log cycle at the end of storage. The presence of probiotic organisms enhanced proteolysis significantly in comparison with the control batch containing L. delbrueckii ssp. bulgaricus Lb1466 and S. thermophilus St1342 only. The proteolytic activity varied due to termination pH, but also appeared to be strain related. The increased proteolysis improved survival of L. delbrueckii ssp. bulgaricus Lb1466 during storage resulting in lowering of pH and production of higher levels of organic acids, which might have caused the low cell counts for B. lactis LAFTI^® B94.     

Improving Acid Production in Soy-Based Yogurt by Adding Cheese Whey Proteins and Mineral Salts

Studies were conducted to further elucidate factors responsible for inability of S. thermophilus and L. bulgaricus yogurt culture to produce lactic acid and flavor in soy-based yogurt made with isolated soy protein and soymilk. Partial replacement of ISP with fresh cheese whey or whey protein isolate, or addition of phosphate and citrate ions resulted in physical stability defects in soy-based yogurt. They also failed to improve acid and flavor development or provide a 1:1 number concentration ratio of the two culture bacteria types. SM-based yogurt had lower acid development than ISP-based yogurt. Addition of commercial sodium caseinate stimulated acid development in SM-based yogurt.     

Influence of bacteria used as adjunct culture and sunflower oil addition on conjugated linoleic acid content in buffalo cheese

The influence of bacteria and sunflower oil addition on conjugated linoleic acid content (CLA) in buffalo cheese was determined. Fresh and short-ripened cheeses were manufactured using the same starter culture and four different adjunct strains previously selected by their CLA production rate. Lactobacillus casei, Lactobacillus rhamnosus, Bifidobacterium bifidum and Streptococcus thermophilus were individually used as adjunct culture. Sunflower oil (SO) was added to obtain a final concentration of 200 μg/ml of linoleic acid. CLA levels in cheese were higher than raw milk, especially after ripening time. SO supplementation increase CLA concentrations in fresh cheeses, except in those manufactured with S. thermophilus as adjunct culture. Both, ripening and SO supplementation showed a positive influence on CLA concentration. Similar texture, acidity and colour were determined in cheeses with or without SO supplementation. Buffalo cheeses manufactured with appropriate adjunct cultures may be a natural source of CLA for human consumption.     

Production of novel dairy products using actinidin and high pressure as enzyme activity regulator

Milk clotting for the production of novel dairy products, alternative or complementary to cheese and yogurt type products can be achieved using plant sulfhydryl proteases. The objective was to apply the protease actinidin, from Actinidia chinensis, as the milk clotting agent, and High pressure (HP) technology to control excessive proteolysis. The effect of the dairy substrate and the process parameters on the coagulation rate and the texture and sensory properties of the end product, were studied. Selected values of design parameters were 25% total solids, 6.49 adjusted pH, 0.35 U activity of the clotting agent actinidin, 40 ºC process temperature and 2 h time. The selected pressure-temperature conditions, 600 MPa at 40 ºC, were applied to stop the potentially detrimental further proteolytic action of the enzyme. Results indicated that use of actinidin for milk clotting and HP to stop the enzyme activity in the final product, leads to a “fresh cheese” type dairy product.Industrial relevance: Alternative clotting methods for novel dairy products, complementary to cheese and yogurt type products, are of interest to the industry. Plant proteases can be a viable approach, provided that excessive proteolysis after structure formation is regulated. High hydrostatic pressure can be used for controlling proteolytic activity in the final products without affecting their texture and sensory characteristics.