Thermophilic Starter Research Articles

ВЛИЯНИЕ НАТУРАЛЬНЫХ РАСТИТЕЛЬНЫХ ПОРОШКОВ НА КАЧЕСТВО ЙОГУРТА

The prospects for the enrichment of yoghurts with vegetable powders have been studied. The purpose of research is to study the possibility of enriching yogurt with biologically active substances of plant powders, to develop the formulation of the product and to study microbiological, organoleptic and physico-chemical parameters. Tasks: to develop recipes for yogurt with vegetable powders; to conduct a comparative assessment of the quality of yoghurts with different dosages of the introduced components; to investigate organoleptic, physico-chemical indicators of quality and safety. The objects of the study were samples of yogurt made by the tank method with thermophilic starters YF-L812, with the addition of dry powders ((Solanum lycopersicum), (Ocimum basilicum), (T. caerulea (L.) Ser.)). Samples were produced at Yurginsky Gormolzavod LLC, Yurga, Kemerovo Region. Yogurt quality indicators were determined according to GOST 31981-2013, organoleptic indicators – according to GOST R ISO 22935-2-2011. A sensory scoring scale were developed. Statistical evaluation was carried out for three replications, at a significance level of 95 % (p < 0.05). Fortified yogurt formulations were developed. The data on organoleptic and physico-chemical parameters are presented. It was found that enrichment (from 2.51 to 5.0 g per 1 kg of product) with a mixture of powders changes the flavor composition and improves organoleptic evaluations. Samples with a mixture of tomato and fenugreek powders had the best results. It was found that when using the product with tomato additives in 400 g, the proportion of the physiological norm of the daily requirement for vitamins was the largest (C – 70 %, A – 11.52, B1 (thiamine) – 25.3 %). No significant difference (p > 0.05) in terms of physicochemical parameters (proportion of protein, fat, dry matter, dry skimmed milk residue) was found between the enriched samples and the control. Compliance of the samples with the safety requirements, TR TS 021/2011, 033/2013 and GOST 31981 for microbiological indicators was established. The developed samples of yoghurts are recommended to dairy industry enterprises as enriched products with natural herbal supplements.

INVESTIGATION OF THERMOPHILIC MICROFLORA FOR THE SELECTION OF STARTER CULTURE COMPOSITION FOR A FUNCTIONAL PRODUCT

Fermented dairy products have valuable nutrients and contain a large number of living cells of lactic acid bacteria strains of lactic acid bacteria. The selection of microorganisms according to their technological and microbiological properties and their ability to develop in a dairy base, as well as organoleptic and rheological parameters of the finished fermented milk product, is an important stage in the development of new types of products. Therefore, special attention was paid to the selection of starter cultures for the production of a functional product. The authors conducted research on the selection of starter culture microflora for the production of functional products. The microbiological and organoleptic properties of selected microorganisms have been studied. When selecting microorganisms, the intensity and direction of the microbiological and biochemical processes occurring during fermentation were taken into account, which is determined by the development of the starter microflora. Thermophilic starter culture by species Lactobacillus acidophilus, Streptococcus thermophiles, Lactobacillus bulgaricus was used in the work.

Development of camel milk cheese technology and research of qualitative characteristics

Recently, interest in the production of camel milk and products from it has increased due to its nutritional and medicinal properties, including camel milk cheeses.In this study, the technology of cheese from non-pasteurized camel milk using mesophilic and thermophilic starter cultures was developed. The composition of camel milk and its microbiological safety indicators were studied. Next, three experimental types of camel milk cheese were prepared, where the physico-chemical composition, cheese yield, mineral composition and organoleptic parameters were determined. Thus, the content of the mass fraction of fat in the studied samples ranged from 25.45 to 22.13%. The mass fraction of solids for all samples was in the range of 50.50-62.30%; ash content was 3.05-3.65%; and the mass fraction of proteins was 17.49, 22.19%, respectively, in the control sample, cheese using mesophilic and thermophilic starter cultures. The cheese yield ranged from 115.20g/l to 137.98 g/l. The mineral composition of camel milk cheese showed that macronutrients such as Na, Mg, Ca, K, P. predominate in all samples. Also, all experimental samples of camel milk cheese had high organoleptic characteristics.

Comparison of Fig Juice Fruitghurt with Variations in Sucrose and Length of Fermentation

Fruitghurt is a fermented product made from fruit juice and milk, which is an important food source of protein to meet nutritional needs. Therefore, researchers added figs containing glucose, fructose, dietary fiber, and antibacterial properties to get the best fruit yoghurt. This study aims to determine the effect of sucrose concentration and the length of fermentation time for fig juice fruitghurt using Lactobacillus bulgaricus and Streptococcus thermophilus starters and to determine the antibacterial activity of fruit juice and fruitghurt through testing against Escherichia coli. Concentration was 0, 14, and 18%, and fermentation was carried out for 0, 18, and 24 hours, The parameters of this research were based on microbiological, chemical, and physical properties. The research showed that sucrose concentration and fermentation time affected Lactic Acid Bacteria (LAB), pH, , pH decreased from 4.5 to 4.0Total Titrated Acid (TAT), viscosity, total dissolved solids, color, aroma, texture, and taste. Total BAL had the highest value of CFU/mL, and TAT increased from 0.50% to 0.65%. The viscosity with the highest value is 12.33 cP. Total dissolved solids decreased from 13% to 11%. All parameters meet the requirements of SNI 2981:2009. The antibacterial activity test showed an inhibition zone with a value of 7.4 mm. The average value of the researcher's preference for color, taste, and aroma in the 0-hour formula with 0% sucrose, the 24-hour formula with 14% sucrose, and the 24-hour formula with 18% sucrose. The best fermentation time and sucrose concentration was 24 hours and 18% sucrose.

COMPARATIVE STUDY OF FERMENTATION PROCESSES OF YAK AND COW MILK

Yak milk is a valuable raw material for the production of functional food. Investigation of the fermentation process with commercial starter cultures is conducted to find suitable starters for producing fermented yak milk products on an industrial scale using modern rheological, microbiological, and sensorial methods. According to the acidification curve and rheological measurement, the gel-forming time of yak milk with mesophilic, thermophilic and mixed (meso-thermophilic) starter cultures was not significantly different from cow milk; but, yak milk had a significantly higher gel strength in all cases. The viable bacteria count of fermented samples with thermophilic starters was 8.23 log CFU∙mL-1 for cow milk and 9.12 log CFU∙mL-1 for yak milk. During cold storage (72 h), the CFU in yak milk remained higher (98.48% – 101.22%) during the storage period than that of cow milk (90.33% – 95.06%). The sensorial property scores of yak milk fermented with mixed starters were the highest, followed by those of milk fermented with mesophilic and thermophilic starter cultures. The obtained parameters show that mesophilic and mixed cultures are advantageous in terms of sensorial and probiotic properties, and thermophilic culture - in terms of gel strength. All this information is useful for the development of new dairy products.

Effect of Probiotic Lactobacillus helveticus on Various Health Disorders

Abstract: The gut microbiota has been linked to the pathogenesis of stress-related illnesses in a growing number of research. Chronic stress may alter behaviour, cognition, biochemistry, and gut flora. Gut bacteria may impact the brain and body by communicating with the host through the microbiota-gut-brain axis (mostly immunological, neuroendocrine, and neurological pathways). It is thought that taking probiotics might help with persistent stress-induced depression. Lactobacillus helveticus is a commonly used industrial thermophilic starter in manufacturing a variety of cheeses by fermenting milk. An increasing amount of scientific data suggests that strains of L. helveticus exhibit health-promoting qualities and their technical significance. In this review, we summarize the findings of several main literature publications on the capacity of L. helveticus strains to affect human health favourably

Storage related changes in short-set cream cheese manufactured using thermophilicstarter culture and direct acidification technique

Cream cheese is a fresh acid curd variety with semi-soft body, manufactured by the gradual, quiescent acid gelation of milk. The typical flavour profile of cream cheese is cultured diacetyl with little bit lactic acid flavour as well as aroma. It is envisaged that demand of cream cheese will increase in upcoming years due to its application as spread and it having higher nutritional value compared to similar products available in the market. The purpose of the study was to observe changes in sensory, physicochemical and microbial quality during storage in short-set cream cheese samples manufactured by using thermophilic starter culture and direct acidification technique and was compared with control cream cheese manufactured using mesophilic starter culture. All the three samples i.e., control cream cheese made using mesophilic culture (MC), cream cheese made using thermophilic culture (TC) and cream cheese made using laboratory grade lactic acid (SLA) were stored in re-closable polypropylene tubs at 7 ± 2°C. During storage study, flavour score, FFA, tyrosine value were significantly affected by storage period (P), treatment (T) and the interaction of T × P. Moisture, pH, titratable acidity, sensory parameters (except flavour) were significantly affected only by storage period (P) and treatment(T). All the three samples had storage stability up to 15 days at 7± 2°C.

Microbiological Characterization of Greek Galotyri Cheese PDO Products Relative to Whether They Are Marketed Fresh or Ripened

Galotyri is the most popular traditional Greek PDO soft acid-curd cheese. This study compared the microbial numbers and types and characterized the lactic acid bacteria (LAB) biota of two artisan-type Galotyri PDO cheese varieties, one marketed fresh (Brand-K) and the other ripened (Brand-Z). Two retail batches of each cheese variety were analyzed, and a total of 102 LAB isolates were biochemically identified. LAB (7.2–9.3 log CFU/g) prevailed in all cheeses, followed by yeasts (5.8–6.8 log CFU/g). Typical starter strains of Streptococcus thermophilus and Lactobacillus delbrueckii were the most abundant species in all batches. However, the fresh Brand-K cheeses had 1–3 log units higher thermophilic starter LAB counts than the ripened Brand-Z cheeses, which contained a more diverse viable LAB biota comprising Lacticaseibacillus paracasei, Leuconostoc mesenteroides, Lentilactobacillus (L. diolivorans, L. kefiri, L. hilgardii), Pediococcus inopinatus/parvulus, few spontaneous nonstarter thermophilic streptococci and lactobacilli, and Enterococcus faecium and E. faecalis at higher subdominant levels.Conversely, the fresh Brand-K cheeses were enriched in members of the Lactiplantibacillus plantarum group; other LAB species were sporadically isolated, including Lactococcus lactis. All retail cheeses were safe (pH 3.9–4.0). No Salmonella spp. or Listeria monocytogenes were detected in 25-g samples by culture enrichment; however, Listeria innocua and coagulase-positive staphylococci (850 CFU/g) survived in one ripened batch. Gram-negative bacteria were <100 CFU/g in all cheeses. In conclusion, ripening reduced the starter LAB viability but increased the nonstarter LAB species diversity in the present Galotyri PDO market cheeses.

Revealing the microbial heritage of traditional Brazilian cheeses through metagenomics

Brazilian artisanal cheeses date from the first Portuguese settlers and evolved via local factors, resulting in unique products that are now part of the patrimony and identity of different Brazilian regions. In this study, we combined several culture-independent approaches, including 16S/ITS metagenetics, assembly- and deep profiling-metagenomics to characterize the originality of the microbiota of five varieties of Brazilian artisanal cheeses from the South and Southeast regions of Brazil. Their core microbiota contained mainly lactic acid bacteria (LAB), of which Lactococcus lactis subsp. lactis was the most frequent, followed by Streptococcus thermophilus in the South region. Moreover, several samples from the Southeast region contained, as dominant LAB, two other food Streptococci belonging to a new species of the salivarius group and S. infantarius. Rinds of samples from the Southeast region were dominated by the halotolerant bacterium Corynebacterium variabile, and the yeasts Diutina catenulata, followed by Debaryomyces hansenii and Kodamaea ohmeri. Rinds from the South region contained mainly LAB due to their short ripening time, and the predominant yeast was D. hansenii. Phylogenomic analysis based on L. lactis metagenome-assembled genomes (MAGs) showed that most Brazilian strains are closely related and form a different clade from those whose genomes are available at this time, indicating that they belong to a specific group. Lastly, functional analysis showed that S. infantarius acquired a ∼ 26 kb DNA fragment from S. thermophilus starter strains that carry the LacSZ system, allowing fast lactose assimilation, an adaptation advantage for growth in milk. Finally, our study identified several areas of concern, such as the presence of somatic cell DNA and high levels of antibiotic resistance genes in several cheese microbiota, suggesting that milk from diseased animals may still be used occasionally. Overall, the data from this study highlight the potential value of the traditional and artisanal cheese production network in Brazil, and provide a metagenomic-based scheme to help manage this resource safely.

Impact of different starter cultures and Lactobacillus helveticus on volatile components, chemical and sensory properties of pasta filata cheese

L.helveticus is known to follow mainly similar metabolic pathways to contribute to cheese flavor with S. thermophilus and L. delbrueckii subsp. bulgaricus. In this study, the flavor contributions of commercial S. thermophilus starter cultures of different brands and L. helveticus adjunct culture to pasta filata type fresh Kashar cheese were investigated. L. helveticus affected the buttery aroma components of fresh Kashar cheese and resulted in low diacetyl content. In addition, acetaldehyde and other aroma components of L. helveticus added cheese was found to be higher than control and modified control cheeses. On the other hand, the modified control sample containing S. thermophilus from Danisco instead of Chr-Hansen in the control was closer to the control sample in terms of volatile profile. As the shelf-life progressed, the contribution of alcohols and hydrocarbons to volatile components decreased, while the contribution of ketones, which was the dominant group, increased in all products. When the proteolysis and lipolysis levels were examined, the control sample differed from the other two cheese samples with its high proteolysis and lipolysis rate. In summary, the rates of increase in water-soluble nitrogen and free fatty acid contents in 8 weeks of storage (from 18 to 72 days) were determined as 61% and 47%, respectively, in the control Kashar cheese, while it was 39% and 27% in the L. helveticus added sample, and 37% and 28% in the modified control sample. Finally, the sensory scores revealed that cheese flavor and texture preferences could be increased with the addition of L. helveticus.

Recreating pink defect in cheese with different strains of Thermus bacteria

Pink discoloration defects in cheese manifests as the appearance of pink patches within cheese blocks and has recently been associated with Thermus thermophilus. Swiss‐type cheeses were prepared at pilot scale using thermophilic starter cultures, Propionibacterium freudenreichii, and one of Thermus thermophilus HB27, Thermus scotoductus SE1 or Thermus thermophilus DPC6866 or a control without Thermus. Significantly, a higher level of redness was observed in cheeses with Thermus thermophilus HB27 relative to the other cheeses and suggests that the development of the pink defect is dependent on the strain of Thermus present and on other, as yet unknown, factors that require further study.

Unravelling the Potential of Lactococcus lactis Strains to Be Used in Cheesemaking Production as Biocontrol Agents.

This research, developed within an exchange program between Italy and Canada, represents the first step of a three-year project intended to evaluate the potential of nisin-producing Lactococcus lactis strains isolated from Italian and Canadian dairy products to select a consortium of strains to be used as biocontrol agents in Crescenza and Cheddar cheese production. In this framework, the acidification and the production of nisin in milk, and the volatile molecule profiles of the fermented milk, were recorded. The strains were further tested for their anti-Listeria monocytogenes activity in milk. The data obtained highlighted good potential for some of the tested strains, which showed production of nisin beginning within 12 h after the inoculation and reaching maximum levels between 24 and 48 h. The highest inactivation levels of L. monocytogenes in milk was reached in the presence of the strains 101877/1, LBG2, 9FS16, 11FS16, 3LC39, FBG1P, UL36, UL720, UL35. The strains generated in milk-specific volatile profiles and differences in the presence of fundamental aromatic molecules of dairy products, such as 2-butanone and diacetyl. The results highlight the interesting potential of some L. lactis strains, the producer of nisin, to be further used as biocontrol agents, although the strains need to be tested for interaction with traditional thermophilic starters and tested in real cheesemaking conditions.

Physicochemical and textural characteristics and volatile compounds of semihard goat cheese as affected by starter cultures

Today, cheese is valued because of its high nutritional value and unique characteristics. Improving the texture and flavor of cheese by selecting suitable starter cultures is an important way to promote the development of cheese industry. The effect of starter cultures on the physicochemical and textural properties and volatile compounds during the ripening of semihard goat cheese were investigated in this work. Different starter cultures-mesophilic (M) and thermophilic starters (T), Lactobacillus plantarum ssp. plantarum ATCC 14917 (Lp), a mix of the M and T starters (M1), and mix of the M, T, and Lp starters (M2)-were used in the production of the goat cheeses. Volatile compounds were determined by a solid-phase microextraction/gas chromatography-mass spectrometric (SPME/GC-MS) method. The results showed that the moisture content of cheeses produced with the 5 kinds of starter cultures decreased after maturation, whereas ash content increased. The pH values of goat cheeses decreased first and then increased during maturity, and the pH value of M2 cheese was the lowest among the cheeses. The hardness and chewiness of the cheeses increased with increasing maturity, whereas cohesiveness, springiness, and resilience showed the opposite tendency. The 60-d-old cheese made with Lp had the highest chewiness, cohesiveness, springiness, and resilience, whereas the 60-d-old cheese made with M2 had the highest hardness. A total of 53 volatile components were identified by SPME/GC-MS, and carboxylic acids, alcohols, ketones, and esters were the 4 major contributors to the characteristic flavors of the cheeses. Volatile components and their contents differed greatly among the produced cheeses. The M2 cheese contained the highest relative content of the main volatile compounds (90.10%), especially butanoic acid and acetoin. Through a comprehensive comparison of the results, we concluded that M2 cheese had a dense texture and milky flavor, and M2 is a potential starter culture candidate for the production of goat cheese.

Influence of starter culture on nitrogen fraction and volatile compounds in Beaten cow's milk cheese

The aim of this investigation was to characterize the influence of selected starters (Streptococcus thermophilus, Lb. casei, Lactobacillus delbrueckii subsp. bulgaricus, Lactococcus lactis subsp. lactis and Lc. lactis subsp. cremoris) on gross composition, the breakdown of proteins or peptides, and volatile compounds of the beaten cheese made from cow's milk. Results showed a low level of primary proteolysis, expressed by a low content of non-casein nitrogen (NCN), in raw cow's cheeses. Greater differences were observed in RP-HPLC peptide profiles between the cheeses manufactured with or without starter cultures during ripening. Volatile profiles including alcohols (17), ketones (33), esters (10), acids (7), and miscellaneous (4) were differed based on used starter culture. Variations on the chemical composition, peptides, and flavor profiles of beaten cheeses are due to the effect of important peptidase activity of each cell species of starter culture used in cheese production. Practical applications Lactic acid bacteria provide to beaten cheese flavor quality with their peptidase activity. Traditional cheese-making technology is made without the addition of lactic acid bacteria depending on the indigenous flora of the milk for ripening. Recently, mesophilic and/or thermophilic starter cultures were used in the manufacture of Beaten cheese. No previous investigation on using starter culture in Beaten cheese has been published and may ensure details to upgrade the technology and ripening by extending the flavor of the current product as its standard variety. Starter cultures can increase flavor evolution or contribute additional flavors to cheese as it matures and control off-flavors in matured cheeses that can considerably economize the cheese production.

Effect of commercial yogurt starter cultures on fermentation process, texture and sensoric parameters of white yogurt

In this work, we have compared and described the fermentation process of two commercial yogurt starter cultures during the white yogurt production. We used freeze-dried thermophilic starter culture YoFlex® YF - L812 and deep-frozen starter culture Delvo® Fresh YS – 241 for the production of white yogurts. We analysed titration acidity, active acidity, total viable counts, texture, and sensory parameters of white yogurts produced in laboratory conditions. This research was performed for dairy company Mliekareň Kopanice Selce, s.r.o., Slovakia. We did not found statistically significant differences (p >0.05) in titration acidity of both yogurts after 7 hours of fermentation. We did not found statistically significant differences (p >0.05) in the pH of both yogurts after 7 hours of fermentation. We found statistically significant differences (p <0.05) in all textural parameters (hardness, consistency, cohesion, and viscosity). The total viable count of microorganisms in yogurts after 24 hours of fermentation was 6.28 x 107 and 7.14 x 107 respectively.

Suitability of the Nisin Z-producer Lactococcus lactis subsp. lactis CBM 21 to be Used as an Adjunct Culture for Squacquerone Cheese Production.

Simple SummaryThis study investigates the potential of a nisin producer, i.e., Lactococcus lactis strain, in the making of Squacquerone cheese. The finding of this research indicates that the tested Lactococcus lactis strain represents a suitable candidate to be used as adjunct culture in Squacquerone cheesemaking since it improved the safety and sensory quality of the product without negatively affecting rheological characteristics and proteolysis.This research investigated the technological and safety effects of the nisin Z producer Lactococcus lactis subsp. lactis CBM 21, tested as an adjunct culture for the making of Squacquerone cheese in a pilot-scale plant. The biocontrol agent remained at a high level throughout the cheese refrigerated storage, without having a negative influence on the viability of the conventional Streptococcus thermophilus starter. The inclusion of CBM 21 in Squacquerone cheesemaking proved to be more effective compared to the traditional one, to reduce total coliforms and Pseudomonas spp. Moreover, the novel/innovative adjunct culture tested did not negatively modify the proteolytic patterns of Squacquerone cheese, but it gave rise to products with specific volatile and texture profiles. The cheese produced with CBM 21 was more appreciated by the panelists with respect to the traditional one.

Potential growth of Listeria monocytogenes in Italian mozzarella cheese as affected by microbiological and chemical-physical environment

In the present study, 33 brands of mozzarella cheese (pasteurized cow milk mozzarella obtained by direct acidification through the addition of food-grade citric acid or obtained by natural acidification through the addition of thermophilic starter cultures, mozzarella for pizza mainly obtained by addition of citric acid, and pasteurized buffalo milk mozzarella obtained by adding microbial rennet) were characterized for the factors potentially influencing the growth of Listeria monocytogenes (microbial populations, moisture, pH, and organic acids). Then, the growth potential of L. monocytogenes in mozzarella was investigated by challenge tests performed at different temperatures. The presence of heterogeneous microflora (lactobacilli, streptococci, Pseudomonas spp., and, for buffalo mozzarella, yeasts) was evidenced. Almost all the product typologies were classified as high-moisture mozzarella cheese because moisture was >52%. Moreover, pH varied from 5.32 to 6.43 depending on the manufacturing methodology applied. Organic acid concentrations too showed great variability depending on the mozzarella production method, with values ranging from less than limit of detection (LOD; 16 mg/kg) to 14,709 mg/kg, less than LOD (216 mg/kg) to 29,195 mg/kg, and less than LOD (47 mg/kg) to 1,725 mg/kg in the water phase of lactic, citric, and acetic acids, respectively. Despite this presence, the concentration of undissociated acids was lower compared with the minimum inhibitory concentrations estimated for L. monocytogenes by other authors. This was confirmed by the results of the challenge tests conducted inoculating the pathogen in mozzarella produced with the addition of citric acid, as the microorganism grew fast at each temperature considered (4, 9, 15, and 20°C). Good hygiene practices should be strictly applied, especially with the aim of avoiding postproduction contamination of mozzarella, as the presence of organic acids and microflora is insufficient to prevent L. monocytogenes growth.

Chemical analysis and flavor properties of blended orange, carrot, apple and Chinese jujube juice fermented by selenium-enriched probiotics

Preparation of selenium-enriched probiotics and Se-enrichment of probiotic-fermented blended juices were performed and optimized using orthogonal test. Se content had a significant 13.0-fold increase by the addition of 1% Se-enriched Streptococcus thermophilus starters in juice fermentation. Chemical properties of fermented blended juices were determined. Reducing sugar content decreased significantly after fermentation, and the same downtrend was observed for free amino acids and organic acids, with lactic acid being an exception. Meanwhile, dynamic variation analysis of flavor components during the fermentation, and characteristic aroma-active compounds before and after fermentation were demonstrated by GC–MS and GC–O. Eleven aroma-active substances were identified from juices without fermentation, while 7 characteristic compounds were detected in fermented juices. Furthermore, potential correlations between chemical and flavor characteristics were explored based on multivariate statistical analysis. These results indicate that a potential Se-enriched fermented beverage was established, and the fermentation process led to differences in the chemical substrates and impact odorants.

Novel isolates of Streptococcus thermophilus bacteriophages from group 5093 identified with an improved multiplex PCR typing method

Bacteriophages are a persistent problem in dairy plants. Streptococcus thermophilus is a component of thermophilic starter cultures used for cheese and yoghurt production. In this study, a multiplex PCR method was adapted to identify, in a single reaction, all known S. thermophilus phage groups. The method was compared with the previously published multiplex PCR typing method and showed higher specificity for classifying purified phage isolates. Three new representatives of phage group 5093, which were discovered with the developed PCR method, were genome sequenced and the genomes were compared with those available in GenBank. A validation of the two typing methods performed with whey revealed limitations of multiplex PCR assays when applied for the detection of phages in dairy samples. This study established an improved multiplex PCR method for classifying purified S. thermophilus phages, and expanded the genetic information of group 5093, both important steps to control phage infections in dairies.

Effect of levels of starter culture and varients of packaging materials on the quality characteristics of enriched misti dahi

The research was undertaken to access the effect of starter culture on the qualitative characteristics of whey protein enriched misti dahi through incorporation of whey protein concentrate @ 2.0 % whey protein concentrate and fruit juice (apple and orange - 1:1) @ 15.0 % by weight. The thermophilic starter cultures were added @ 1.0, 2.0 and 3.0 % level. Incorporation of starter culture @ 2.0 % rate yielded product having acceptable sensory attributes. Misti dahi packaged in polyethylene teraphthalate (PET) cups could be stored for longer period (i.e. 15 days) as compared to use of polystyrene, polypropylene cups or even earthen pots, when stored under refrigerated (4±2 oC) condition.