Yogurt Starter Research Articles

Selection of Tempoyak Lactic Acid Bacteria As Candidate Strain for Yoghurt Starter Culture

Selection of bacteria in yoghurt fermentation is important to produce yoghurt with good quality. Tempoyak lactic acid bacteria is potential to be yoghurt starter culture becouse tempoyak fermentation has similarities in producing lactic acid such as yoghurt. This study aimed to isolate and identify the lactic acid bacteria (LAB) from tempoyak which will be used as a yoghurt starter culture. The methods used in this study included isolation and selection of acid-producing bacteria, lactase and protease activity test, identification of morphology and biochemistry as well as testing the quality of the yoghurt. The results of the study obtained 32 isolates of the LAB with the same characteristic colony, include the round shape, cream-coloured with convex elevation and, smooth surface and entire edge. Selection of acid-producing bacteria obtained 12 isolates with the ability to produce clear zones on MRSA + CaCO3 media ≥ 0.7 cm. Selection of lactase-producing LAB obtained six strains and the protease test obtained two superior strains. Two superior strains namely Tp 12 and Tp 28 have characteristics of coccus, gram-positive, negative catalase, non-endospore and non-motile forms. The organoleptic and several quality tests showed yoghurt using Tp 12 as starter has higher acceptability, the highest levels of lactic acid and lactose levels with values respectively 4.25, 0.84% and 24.53%. This study obtained the LAB strain which can be used as yoghurt starter culture. Tp 12 strain can be used to improve the quality of yoghurt and become a commercial starter that can be applied to various fermented products.

The Combined Effect of Phytosterols and Lactulose Supplementation on Yoghurt Quality

This study aimed to evaluate the physicochemical, microbiological, rheological and sensorial properties of yoghurt enriched with phytosterols (1.6%) and /or lactulose (6%), during refrigerated storage. Compared with the control yoghurt, postacidification and syneresis were reduced in all enriched samples. Besides, yoghurt starter counts were affected neither by phytosterols nor by lactulose addition, during storage. Otherwise, yoghurt samples enriched with both phytosterols and lactulose had a lower oxidationand better rheological properties. Also, their sensory characteristics were appreciated by consumers.

Associations of Probiotic Fermented Milk (PFM) and Yogurt Consumption with Bifidobacterium and Lactobacillus Components of the Gut Microbiota in Healthy Adults

The current study investigates whether probiotic fermented milk (PFM) and yogurt consumption (YC) are related to both the ingested bacteria taxa and the overall gut microbiota (GM) composition in healthy adults. PFM and YC habits were analyzed in 260 subjects (51% male) by specific questionnaires, and the following groups were considered: (1) PFM groups: nonconsumers (PFM-NC, n = 175) and consumers (PFM, n = 85), divided as follows: Bifidobacterium-containing PFM (Bif-PFM; n = 33), Lactobacillus-containing PFM (Lb-PFM; n = 14), and mixed Bifidobacterium and Lactobacillus-containing PFM (Mixed-PFM; n = 38); (2) PFM-NC were classified as: yogurt nonconsumers (Y-NC; n = 40) and yogurt consumers (n = 135). GM was analyzed through 16S rRNA sequencing. PFM consumers showed higher Bifidobacteria taxa levels compared to NC, from phylum through to species. Specifically, Bif-PFM consumption was related to higher B. animalis levels (p < 0.001), whereas Lb-PFM consumption was associated to higher levels of Bifidobacterium (p < 0.045) and B. longum (p = 0.011). YC was related to higher levels of the yogurt starter Streptococcus thermophilus (p < 0.001). Lactobacilli and the overall GM were not related either to YC or PFM consumption. According to these results, healthy adults might benefit from PFM intake by increasing Bifidobacterium levels.

Screening of aroma-producing lactic acid bacteria and their application in improving the aromatic profile of yogurt.

The development of yogurt flavor is a complicated and dynamic biochemical process. In addition to traditional starter cultures, adjunct cultures could also make significant contributions to the flavor profiles of yogurt. In the current study, two Lactobacillus plantarum strains (1-33 and 1-34) were isolated based on their abilities to produce acetaldehyde and diacetyl. In co-fermentation with traditional starters, these isolated strains were able to maintain viability without affecting the yogurt's acidification profiles. Furthermore, they positively influenced the aroma quality of the yogurt samples. They promoted the formation of volatile metabolites, especially acetaldehyde, diacetyl, and acetoin, which are recognized as characteristic compounds. The results of this work provide novel knowledge about the contributions of isolated strains on the flavor profiles of yogurt, which will help to improve the organoleptic properties of the final products. PRACTICAL APPLICATIONS: Using lactic acid bacteria (LAB) as adjunct cultures co-fermented with traditional yogurt starter cultures can increase the quantities of flavor compounds in yogurt. This study enriches our understanding of the effects of adjunct cultures on yogurt flavor. Researchers and manufacturers that specialize in yogurt making can use the results of this study to improve the aromatic profile and organoleptic quality of yogurt.

Effects of Fermentative Factors on Biochemical, Microbiological and Sensory Characteristics of Probiotic Iranian Fermented Milk (Doogh)

Background: Doogh is a traditional Iranian fermented milk drink that is currently a very popular product in Iran. In the present study, the combined effects of incubation temperature, type of starter culture, and final pH of fermentation on the viability of two probiotic strains (Lactobacillus acidophilus La-5 (A) and Bifidobacterium lactis Bb-12 (B)) and biochemical and sensory characteristics of probiotic Doogh were investigated. &lt;/P&gt;&lt;P&gt; Method: Different treatments were prepared with yoghurt starter culture containing probiotics, using reconstituted skimmed milk with 6% of solid nonfat. They were incubated at 38°C or 44°C until pH 4.0 or pH 4.5 and were kept for 21 days at 4&amp;#176;C or 8&amp;#176;C storage temperature. The biochemical properties of treatments were evaluated during fermentation and refrigerated storage. The viable count and sensory attributes of treatments were studied at the end of fermentation and at the end of storage. &lt;/P&gt;&lt;P&gt; Results: Results showed that the greatest mean pH drop rate, mean acidity increase rate and mean redox potential increase rate and the shortest incubation time were observed in treatments incubated at 44&amp;#176;C with final pH of 4.5. The highest survival of both probiotic strains during storage was related to treatments with fermentation temperature of 38&amp;#176;C and final pH of 4.5. Treatments ABY1-38&amp;#176;C-4.0 had the highest sensorial total acceptance at the end of refrigerated storage. &lt;/P&gt;&lt;P&gt; Conclusion: It would be concluded that the best treatment was ABY3-38&amp;#176;C-4 stored at 8°C in regards of probiotics’ viability and sensory characteristics of Doogh. Thus, controlling the temperature of refrigerated storage is the most importance factor during storage and distribution.

STUDY OF THE INFLUENCE OF DAIRY BAKERY IN THE COMPOSITION OF THE READY PRODUCT FOR THE GROWTH OF THE BACTERIA OF THE BASKET FUEL GROUP

The qualityof bacterial starter cultures of lactic acid bacteria from different manufacturers is analyzed for the expediency of their use in the manufacture of a functional product. The effectiveness of the use of starter cultures brand VIVO-bifivit, yogurt starters, streptosan in preparation of milk products, inhibit the growth of bacteria of group of intestinal sticks isolated from the environment. To determine the effectiveness of the use of starter cultures of different types on the subject of suppressing the growth of coliforms complex ICD conducted coliforms sat down with Petri dishes with the characteristics of E. coli on the jamb with a nutrient Agar (cultivation time of 24 hours at a temperature of 37°C). At the end of the cultivation period, the distribution of BGCP in an amount of 1 cm3 was carried out to infect the prepared functional product with the use of ICD. The optimal time of cultivation OF lactic acid bacteria of vivo starter cultures was established, which is 5-6 hours, which corresponds to the optimal acidity of the product – 50T. The study proved the effectiveness of the use of bacterial starter cultures of various types of VIVO manufacturer to improve the therapeutic and preventive effect of the product by completely suppressing the growth of bgcp. Fermentation method in accordance with DSTU by replanting on elective environments Endo and Gisa was established that all the bacterial sourdough of the trade mark VIVO inhibit the growth of coliforms unlike pharmaceutical microbial drug brand Laktobakterin - Biopharma, as these bacteria are able to suppress the growth of coliforms in spite of the synthesis of lactic acid, as evidenced by a determination oxidase activity and color reactions for indole. The results of studies show: positive oxidase-blue color, indicating that the isolated colonies of Petri dishes with Endo environment to the pathogens of intestinal infections). positive reaction color reaction to indole, which is formed by the decomposition of tryptophan bacteria.

Effects of inulin and lactic acid bacteria strains on aflatoxin M1 detoxification in yoghurt

The aim of this study was to determine the binding ability of three lactic acid bacteria strains (LABs) (L. plantarum ATCC 10697, B. animalis ATCC 27672, and B. bifidum ATCC 35914) to aflatoxin M1 (AFM1) from contaminated yoghurt and phosphate-buffered saline (PBS) either alone or in binary combination for different periods of cold storage (one or ten days) and to investigate the effect of inulin supplementation at 4% concentration on the AFM1 binding ability of LABs. The AFM1 binding capacities of cultures varied, ranging between 49.8 ± 2.53% to 60.8 ± 3.58% and 49.5 ± 2.00% to 55.1 ± 1.67%; the best AFM1 binding was observed with yoghurt starter (YS) + B. bifidum-B. animalis (60.8%) (p < 0.001) and YS + L. plantarum-B. bifidum mixtures (55.1%) (p < 0.01) after one day and ten days cold storage periods, respectively. Inulin supplementation led to increased AFM1 binding capacity of YS + B. bifidum (p < 0.01), YS + B. animalis (p < 0.01), and YS + L. plantarum-B. bifidum (p < 0.001) mixtures at the end of the one-day storage period. Furthermore, the binding capacity of YS + B. bifidum-B. animalis, YS + L. plantarum-B. bifidum, YS + L. plantarum-B. animalis increased with statistical significance at the end of the ten-day storage period by inulin addition (p < 0.05, p < 0.001 and p < 0.001, respectively). The results of this study showed that the use of LABs and inulin in yoghurt manufacture might provide an effective method for AFM1 detoxification and reducing the exposure.

Iron fortification of reduced‐fat bioyoghurt containing either short‐ or long‐chain inulin

This study aimed to evaluate the effect of adding inulin, iron salts and/or their combinations on the physicochemical, microbiological and sensory characteristics of reduced‐fat bioyoghurt. Results revealed that iron and inulin supplementation did not affect the viable counts of the yoghurt starter microorganisms but slightly increased counts of Bifidobacterium animalis subsp. lactis. Iron and inulin significantly affected the textural attributes of the yoghurt, but did not modify the yoghurt flavour significantly. Also, in vitro assessments on the availability of calcium and iron were conducted and revealed that the supplementation of yoghurt with iron and inulin resulted in significant reduction in calcium and iron availability.

The impact of bacterial cultures on changes in contents of PCB congeners in yoghurt and bioyoghurt

Persistent organic pollutants, including polychlorinated biphenyls, may pose serious health hazard to consumers due to their lipophilic character as well as their high stability and toxicity. They are common in milk and also in dairy products. Therefore, to provide consumers with food of the lowest possible level of pollutants, it is important to estimate the influence of technological processes in milk and dairy products manufacture on changes in the contents of toxic PCB congeners. The PCB congeners content was determined using gas chromatography with mass spectrometry. Our study showed that yoghurt starter cultures turned out to be an effective tool in decreasing the toxicity equivalent of yoghurts. The presence of additional two starter cultures of bacteria Lactobacillus acidophilus and Bifidobacterium sp. In the A.B.T. bioyoghurt starter culture was most likely the reason of the highest efficiency of this culture to reduce the value of toxicity equivalent (TEQPCB) in bioyoghurts (reduction by nearly 50 %). However, none of the four tested starter cultures of yoghurts and bioyoghurts ensured complete biodegradation of any of the tested PCB congeners. These cultures contributed to a distinct reduction in contents of the PCB congeners in the finished products and, simultaneously, to a significant increase in PCB 28 and PCB 77, which may result from the degradation of more chlorinated congeners. In consequence it can improve the quality of fermented dairy products.

Survival of &amp;lt;i&amp;gt;Staphylococcus aureus&amp;lt;/i&amp;gt; in Bio-Yoghurt

Introduction: Due to the increasing demand for natural probiotic products, yogurt is the most popular type of fermented dairy products. Aim: Yoghurt produced using probiotic bacteria and its effect on Staphylococcus aureus as a pathogenic microorganism is discussed as compared with traditional yoghurt. Material and method: The influence of yoghurt using starter culture on S. aureus during manufacture and storage for three brands of Lab. made yoghurt (A, B and C) was judged as excellent concerning the total acceptability. Result: The inoculated S. aureus decreases in number by the end of the storage period. In addition, the best effect of inhibition was observed in brand (B) using yoghurt starter with Lactobacillus acidophilus, followed by brand (C) using yoghurt starter L. acidophilus together with Bifidobacterium bifidum and the least effect was belonging to brand (A) using yoghurt starter only. This inhibitory effect may be attributed either to the probiotic bacteria itself or to the antibacterial substances secreted by them. Conclusion: The authors recommended the consumption of bio-yoghurt as it is not only palatable but also, safe due to improved hygienic quality.

The effect of non-conventional starter culture on lipid nutritional quality of fermented dairy products

In this study, the effects of kombucha inoculum as non-conventional starter culture on fatty acids composition of fermented milk, compared to a commercial probiotic (ABT-7) and yoghurt (YF-L812) starter cultures, during 21 days of storage was investigated. Fatty acids composition was determined by gas chromatography-mass spectrometry after the previous extraction of lipids and derivatization. The atherogenic (AI) and thrombogenic (TI) indices determined on the basis of fatty acids composition have been used for evaluation of the nutritive lipid quality of the fermented dairy products. The most significant levels of fatty acids in fermented milk products were palmitic, followed by oleic, stearic and myristic fatty acids. Fermented milk products were characterized by low atherogenic (2.14-2.39) and thrombogenic (2.91-3.18) indices, suggesting their consumption could have a favorable effect on human health. The AI and TI were comparable during the storage of fermented milk samples. Starter culture did not affect the health-related fatty acid composition of fermented milk products during storage.

Physico-Chemical, Microbiological and Sensory Characteristics of Yogurt as Affected by Added Lactose

Enrichment of yogurt with lactose addition may increase the growth of the yogurt starter culture (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus) and enhance yogurt physico-chemical and sensory attributes. The objectives of this study were to determine the influence of added lactose on the 1) physico-chemical characteristics, including the final lactose content of yogurt, during its shelf life; 2) growth of the yogurt starter culture over yogurt shelf life and 3) the sensory attributes of yogurt. Fat free plain set-type yogurt was manufactured using 0%, 1%, 3% and 5% w/w added lactose to accomplish objectives 1 and 2. For objective 3, a blueberry yogurt was manufactured using the same lactose levels. Analyses for plain set-type yogurt were conducted at 7 days intervals during 35 days of storage. Sensory evaluation was conducted on flavored yogurt three days after its manufacture. Data were analyzed using Proc Mixed model of SAS® 9.3 program. Significant differences between means were analyzed at α = 0.05 using Tukey adjustment. Lactose addition influenced some of the yogurt characteristics in a positive manner. Lactose contents of yogurts with lactose added at 1%, 3% and 5% stayed higher in that proportion than control throughout the 35 days of storage. Yogurts containing 5% w/w added lactose had the lowest pH. Yogurts containing 5% w/w added lactose had significantly the highest syneresis values compared to 0%, 1% and 3% w/w added lactose during storage period at day 7 and from day 21 onwards. Use of 5% w/w added lactose resulted in significantly higher counts of Streptococcus thermophilus compared to control and this bacterial survival was the highest for 1% w/w added lactose compared to the rest. The overall liking scores indicated that yogurts containing added lactose were preferred over control. For taste, sourness and sweetness samples containing added lactose had higher scores than control. The consumer acceptability of yogurts increased as lactose addition increased. The acceptability of yogurts and purchase intent frequency scores markedly increased with the addition of lactose.

Effect of Salting Technique on Shreddability, Texture Profile and Microstructure of the Pre-Acidified Cowâ??s Mozzarella Cheese

The aim is to investigate the effect of salting technique together with type of pre-acidification used acid on shreddability, texture profile and microstructure of the full fat cow’s Mozzarella cheese. Mozzarella cheeses were made conventionally from standardized full fat cow’s milk; pre-acidified with either citric, lactic or acetic acid drop-wise to pH of 6.3, using 2.5% activated Yoghurt starter culture and rennet (1.5 g/100 Kg). The milled curds were salted either by the brining technique or by dry salting. The obtained results indicated that, the brine salted cheeses were associated with significant increments in the values of dry matter, protein, fat, calcium, cohesiveness, springiness and adhesiveness. While the application of dry salting led to increase the values of ash, lactose, salt, sodium, hardness, cohesiveness, gumminess and shredding efficiency. Moreover, the microstructure of the brine salted cheeses was more porous, whereas the dry salted cheeses appeared with more homogeneous and continuous protein matrix as well as less pockets. The lactic pre-acidified cheeses were the most shreddable cheeses and distinguished with the highest dry matter, protein, ash, sodium, pH, hardness and cohesiveness, as well as reflected the densest protein network with narrow fat voids. The application of acetic acid was associated with significant increments in the values of fat, lactose, springiness and adhesiveness. Moreover, the citric pre-acidified cheese showed a combination of many larger channels and smaller pores giving an increased porous structure with more sharpened protein fibers.

Physicochemical and Organoleptic Characteristics of Manufactured Buffalo Milk Yoghurt Incorporated Soy and Corn Milks

Soy-corn-yoghurt is a fermented product that obtained from inoculation of yoghurt starter to soy corn milk. The present study was conducted to study the use of different ratios of soy corn milk and corn milk only with buffalo milk in the manufacture of yoghurt. Two experiments were carried out , the first experiment was 100 ml buffalo milk :soy corn milk ratios 90:10, 80:20, 70:30, 60:40 and 50:50 (w/w), the second was buffalo milk with Corn milk 90:10, 80:20, 70:30, 60:40, 50:50 and 40:60 respectively and 100% buffalo milk as control. Treatments were coded B1, C1, D1, E1 and F1 in the first experiment, while B2, C2, D2, E2, F2 and G2 for the second respectively. All treatments subjected to chemical and organoleptic assessment. It was found those pH, total protein, fat content were decreased with increasing the ratio of soy corn milk in the product. Also, increasing the ratio of corn milk led to decrease all the previously mentioned characteristics. Curd firmness values for yoghurt made from (70:30) coded D2 and (60:40) coded E1 were higher than that of other treatments. Results indicated that mixes of (50:50) coded F1, (60:40) coded E1 and mixes (90:10) coded B2, (80:20) coded C2 and (70:30) coded D2 had the highest sensory scores and chemical quality.

Product Optimization of Yogurt Ice Cream flavored with Fermented Cacao Butter (Theobroma cacao L.)

Cacao yogurt ice cream was subjected to optimization study using Box-Behnken design. This study aims to determine the optimum levels of cacao butter as flavorant, yogurt starter and sugar. A total of 15 runs were conducted, following the Box-Behnken design. It was prepared by pasteurization of fresh cow’s milk, addition of yogurt, incubation and freezing. The 15 runs were subjected to physico-chemical, microbiological and sensory analyses. The statistical analysis revealed that high levels of sugar and yogurt starter significantly affect the sensory qualities and physico-chemical properties of the yogurt ice cream. Moreover, the levels of sugar and cocoa butter significantly affect the growth of lactic acid bacteria in the ice cream. The optimized level is composed of 5.23-9.3% cacao, 14-19% sugar and 16-25% yogurt.

Production of Novel Functional Yoghurt Fortified with Bovine Colostrum and Date Syrup for Children

The aim of this work was to study the effect of adding bovine colostrum and date syrup as natural ingredients on the nutritional value of yoghurt and it's quality during cold storage period. Functional yoghurt was prepared by using buffalo milk 3% fat, date syrup 5% for all treatments except the control and bovine colostrum was added at different ratios 5% (T2), 10% (T3) and 15% (T4). Then, all treatments were inoculated with 2% of yoghurt starter andstored at 5°C for 12 days. Samples of yoghurt were chemically, organoleptically, and microbiologically analyzed at 1st, 4th, 8th and 12th days of cold storage. It was observed that addition of date syrup and bovine colostrum for yoghurt were found to enhance significantly the content of total Solids (TS), total protein, immunoglobulin G (IgG), lactoferrin and minerals compared to the control. Also, most nutrients hade a slight increment during advanced storage period. The titratable acidity% of yoghurt samples slightly increased during storage periods, while the pH values decreased significantly.Yoghurt fortified with 10% (T3) and 15% (T4) of bovine colostrum had significantly higher viscosity values than that in the other treatments. Also, T4 had significantly lower syneresis than the other yoghurt treatments on 12th day of storage.No significant differences could be traced in flavour, appearance, body and texture and overall acceptability scores among all yoghurt treatments.The grams consumed of yoghurt to meet the daily requirement (GDR) for children aged 1-3 years of protein and (calcium, phosphorus, iron and zinc) significantly decreased by fortification of yoghurt with date syrup and bovine colostrum, while percent satisfaction (P.S.%/100g) of the daily needs in these nutrients significantly increased. In conclusion, fortification of yoghurt by adding date syrup and bovine colostrum enhanced nutritional value and quality of yoghurt.

Yogurt and other fermented foods as sources of health-promoting bacteria.

Increased consumption of yogurt, kefir, and other fermented foods has been driven, in part, by the health benefits these products may confer. Epidemiological studies have shown that the consumption of fermented foods is associated with reduced risks of type 2 diabetes, metabolic syndrome, and heart disease, along with improved weight management. The microorganisms present in these foods are suggested to contribute to these health benefits. Among these are the yogurt starter culture organisms Streptococcus thermophilus and Lactobacillus delbrueckii subsp bulgaricus as well as Bifidobacterium and Lactobacillus strains that are added for their probiotic properties. In contrast, for other fermented foods, such as sauerkraut, kimchi, and miso, fermentation is initiated by autochthonous microbes present in the raw material. In both cases, for these fermentation-associated microbes to influence the gut microbiome and contribute to host health, they must overcome, at least transiently, colonization resistance and other host defense factors. Culture and culture-independent methods have now clearly established that many of these microbes present in fermented dairy and nondairy foods do reach the gastrointestinal tract. Several studies have shown that consumption of yogurt and other fermented foods may improve intestinal and extraintestinal health and might be useful in improving lactose malabsorption, treating infectious diarrhea, reducing the duration and incidence of respiratory infections, and enhancing immune and anti-inflammatory responses.

Antioxidant, physicochemical, microbiological, and sensory properties of probiotic yoghurt incorporated with various Annona species pulp

In this study, antioxidant, chemical, microbiological, and sensory attributes changes taking place during the production of probiotic yoghurt using pulp of soursop (Annona muricata), sweetsop (Annona squamosa), and custard apple (Annona reticulata) were evaluated. The products were stored at 4 °C for 28 d, during which time physicochemical properties and viability of probiotic bacteria and yoghurt starter cultures were evaluated weekly. Yoghurts prepared with fruit pulps displayed higher antioxidant activities on the first day of storage compared to the control. During the storage, the addition of fruit pulps influenced (p < 0.05) pH, titratable acidity, syneresis and counts of B. animalis ssp. lactis BB-12 of yoghurts, whereas counts of Streptococcus thermophiles and Lactobacillus delbrueckii ssp. bulgaricus were found to be insignificant. Sensory evaluation results showed that yoghurt containing soursop fruit pulp had better sensory scores than other treatments. Therefore, these results proved that soursop can be used to produce probiotic yoghurt with enhanced physicochemical, microbiological and sensory properties.

INKUBATOR PRODUKSI YOGHURT SKALA RUMAH TANGGA UNTUK PERBAIKAN PROSES PRODUKSI DI KABUPATEN KUNINGAN

The quality of yoghurt produced in District of Cipari, Cigugur Kuningan Regency failed to meet the required standard despite the fact that socialization of yoghurt GMP program, facilitation and delivery of inkubator for yoghurt production had been implemented. Therefore, this study reported the performance of the incubators which had been produced and granted to two cooperatives in the District of Cipari, Kuningan, namely Laras Ati and Lembah Kamoning. The method used was to directly test the incubators for the production of yoghurt in a laboratory Institut Teknologi Indonesia and in Kuningan. Five litres of cow's milk that had been heated to a temperature of 90° C for 15 minutes and cooled down to a temperature of 40° C were directly inoculated with a 10% volume of fresh commercial yoghurt starter, culture consisting of Lactobacillus acidophilus, Streptococcus thermophilus and Bifidobacterium. The measured parameters were incubator temperature stability, product's pH value, total acid and organoleptic of product. The results showed that the performance of the two incubators were in good condition. It was proved by stable temperature in the range of 44.1±0.6°C during evaluation within 7 hours of incubation. During fermentation, pH of the product has decreased and reached a pH value of 4.6 ± 0:02 within 7 hours of incubation, total acid reached 0.84±0.052%. The organoleptic product of yoghurt showed the percentage of product acceptance reached 85%, 83%, 86% and 82% in colour/appearance, texture, odour/flavour and taste respectively. The two delivered incubators met the required standard, thereby making the household-scale production process of yoghurt safe for public consumption. Yoghurt ready for sale and kept at the room temperature remains fresh and does not suffer damage because the packaging is not inflated as before.Yoghurt that is ready to be sold and even kept at room temperature remains fresh and does not suffer damage ie. the packaging is not inflated as before.

Yogurt starter cultures of Streptococcus thermophilus and Lactobacillus bulgaricus ameliorate symptoms and modulate the immune response in a mouse model of dextran sulfate sodium-induced colitis

We investigated the yogurt starter cultures of Lactobacillus bulgaricus 151 and Streptococcus thermophilus MK-10 for their effect on the severity of experimental colitis, lymphocyte profile, and regulatory T-cell response. Colitis was induced in BALB/c mice via the administration of 3.5% dextran sulfate sodium salt (DSS) in drinking water for 6 d. Next, the mice were gavaged intragastrically with an active yogurt cultures (YC) mixture (∼5 × 109 cfu/mouse per day) or saline (vehicle) for 8 d. Mice receiving DSS or saline alone served as positive and negative controls, respectively. The length of the colon, disease activity index, histological scores, myeloperoxidase activity, epithelium-associated microbes, short-chain fatty acid profile, total IgA antibody-forming cells, CD3+CD8+, CD3+CD4+, CD3+CD4+CD25+, CD3+CD4+CD25+Foxp3+ T-cell subsets, and cytokine profiles (IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-γ, and tumor necrosis factor) were examined after termination of the mice. Feeding mice with YC mixture reduced disease symptoms and modified intestinal microbiota and host inflammatory responsiveness to DSS. We observed limited weight loss and a decreased disease activity index score, lowered myeloperoxidase activity, and somewhat reduced damage of the intestine. The YC mixture upregulated the colon length, increased the amount and diversity of mucosa-associated microbes (enterobacteria, enterococci, and yeast), and decreased the concentration of putrefactive short-chain fatty acids in the cecal contents. It downregulated the input of cytotoxic CD3+CD8+ T cells and CD3+CD4+CD25+FoxP3+ regulatory T cells in Peyer's patches and enhanced CD3+CD4+CD25+ T cells in spleens and CD3+CD4+CD25+FoxP3+ cells in peripheral blood mononuclear cells. Simultaneously, IgA antibody-forming cells were downregulated in mesenteric lymph nodes (MLN) and enhanced in spleens (SPL). The cultures mostly enhanced the production of cytokines tested in MLN and SPL, except for IL-6, which was downregulated in MLN. Interleukin-2 and IL-4 were the most upregulated in MLN, whereas IL-10, IL-4, IL-2, IFN-γ, and tumor necrosis factor were most upregulated in SPL. In serum, the YC mixture downregulated IFN-γ and clearly increased IL-2. Based on these results, we recognize the high anti-inflammatory and immunomodulatory potential of the L. bulgaricus 151 and S. thermophilus MK-10 set. The strains possess the ability to modulate the intestinal mucosal and systemic immune system toward both IgA production and induction of regulatory T cells, shifting Th1/Th2 balance.