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Subject: Dairy Microbiology × End date: 2021 ×
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    ThesisItemOpen Access
    EVALUATION OF INCORPORATED SOLID STATE FERMENTED (SSF) CULTURES FOR PANEER WHEY BASED IDLI BATTER
    (KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR – 585 401, 2021-07-01) VISWANATHA ANGADI; PRABHA, R.
    The present study was undertaken to improve the nutritional quality of idli by incorporation of paneer whey as well isolated lactic cultures through fermented solid substrate, black gram dhal (SSFC). Soaking time of black gram dhal, rice rava were optimised to 4 h and 1 h, respectively in paneer whey at 70:30 (whey: water). The whey-based batter was fermented at 30℃ for 12 h that showed predomination of lactobacilli that ranged from 5.42 to 8.74 log10 cfu/g on MRS agar medium. Among eighteen lactic isolates, four showed better activities were identified as Leuconostoc sp. strain Leu2, Enterococcus sp. strain E1, Lactobacillus brevis strain Lb1 and Lactobacillus casei strain Lb2 based on 16S rRNA sequence. These four cultures were grown on sterile black gram dhal having skim milk powder and tomato juice and inoculated in the dried form as SSFC at 5% rate during batter preparation. As a result, the fermentation time at 30℃ was reduced (by 25%) to 9 h, compared to control (12 h). The idlis made from 5% SSFC with 70 % whey based batter were most accepted with highest overall acceptability score (8.53) compared to control (7.43). SSFC incorporated whey based idli batter showed 0.36% higher total protein, 13.3% lower phytate content and 28% increase in calcium content in comparison with control. Sensory evaluation of idlis from the optimised 5% SSFC batter stored in LDPE pouches at 4℃ for 4days were accepted and considered safe with no coliforms. The SSF cultures showed the viability of 7.04 log10 cfu/g when stored at 4℃ for 4 months.
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    ThesisItemOpen Access
    FORMULATION AND VALIDATION OF SELECTIVE MEDIA FOR THE ENUMERATION OF LACTIC ACID BACTERIA IN FERMENTED MILK PRODUCTS
    (KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR – 585 401, 2021-07-01) SABHAVAT GOPAL; PRABHA R.
    Market samples of curd, yoghurt probiotic drink and domestic curd samples were enumerated using formulated and readymade media like M17 for lactococci as well as Streptococcus thermophilus and MRS media for lactobacilli incubated in candle jar at 30ºC and 37ºC respectively for 48 h the readymade media gave better recovery of viable cells of lactic acid bacteria. Reduction in lactic counts of fermented milk products was noticed in both M17 and MRS agar after incorporation of calcium propionate and sodium benzoate at 1.5 and 2 per cent each, respectively helped in control of both aerobic spore formers and yeasts. Yeast glucose agar with Bromocresol Purple (BCP) with 0.05 per cent was used which showed better viable counts of lactic acid bacteria than Elliker agar with BCP. In order to reduce aerobic spore forming bacteria and yeasts, calcium propionate of 0.8 per cent and sodium benzoate of 1.2 per cent incorporation to yeast glucose agar with 0.05 per cent BCP led to formation of more than 8 log counts of both yellow and purple colonies. Yellow and purple colonies when subjected for colony morphology demonstrated rods (lactobacilli) and cocci (lactococci), respectively indicating the lactic acid bacteria present in fermented milk products, when inoculated to sterile skim milk set the curd in 8 h with 0.65per cent lactic acid on an average. The correlation coefficient, r was 0.78 between selective M17 of lactococci and selective yeast glucose agar for purple colony of lactic cocci while r was 0.67 when MRS lactobacilli count was compared with yellow colonies of lactobacilli on selective yeast glucose agar indicating good relationship between both the types of selective agar media.
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    ThesisItemOpen Access
    OPTIMIZATION OF BULK CULTURE PROPAGATION FOR THE PRODCTION OF MISTI DAHI
    (KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR – 585 401, 2021-07-01) PALEPU PAVAN KUMAR; RAMACHANDRA, B.
    The misti dahi prepared was studied for the effect of sugar, total solids, inoculum levels and caramel flavours on the performance of cultures of Lactococcus lactis ssp. cremoris, Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus alone and in combination. Sugar at 12.0 per cent got highest overall acceptability score of 8.58, 8.00 and 8.75 using Lactococcus lactis ssp. cremoris, Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus alone and in combination at 1.0 and 2.0 per cent respectively. The misti dahi made with total solids of 31.0 per cent got highest over acceptability score of 8.08, 8.58 and 8.25 using Lactococcus lactis ssp. cremoris, Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus alone and in combination at 1.0 and 2.0 per cent respectively. The misti dahi made with 12.0 and 31.0 per cent sugar and total solids at different levels of inoculum 0.5, 1.0, 1.5 and 2.0 per cent of Lactococcus lactis ssp. cremoris scored highest of 8.00 at 1.0 per cent inoculated culture compared to the other inoculum levels, while misti dahi prepared form 2.0 per cent yoghurt culture got overall highest score of 8.16 when compared to the other levels. In case of misti dahi produced from the mixed cultures of Lactococcus lactis ssp. cremoris and yoghurt culture, misti dahi made with yoghurt culture alone scored highest of 8.00. The misti dahi prepared using natural and artificial flavours, the overall acceptability scores of 8.25 misti dahi made using natural was best. The storage stability of misti dahi was analysed at room and refrigeration temperatures. The misti dahi losts its quality in a single day and 15th days at room temperature (27±1 °C) and refrigeration temperature (5 °C) respectively.
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    ThesisItemOpen Access
    PHYLOGENETIC STUDY OF LISTERIA SPECIES ISOLATED FROM DAIRY ENVIRONMENTAL SAMPLES
    (KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR – 585 401, 2021-07-01) P. SUSHMITHA; PRABHA R.
    In the present study, Listeria count in dairy environmental samples collected from university dairy farm ranged from 0.10 to 4.56 log10cfu/g, out of which soil, dung and udder swab of milch animal showed more Listeria. The pheno and genotypic identity of Listeria revealed as Listeria ivanovii (6 nos; 50.0%), followed by Listeria grayi (5 nos; 41.6 %) and Listeria seeligeri (1 no; 8.40%). Phylogenetic analysis through Neighbour joining method revealed that L. ivanovii L18, L8, L16 and L. grayi L9, L10, L12 were having relatedness about 87% while L. ivanovii L15, L7, L17, L. grayi L11, L13 and Listeria seeligeri L14 had about 92% homology. Non-pathogenic Listeria grayi L13 and pathogenic Listeria seeligeri L14 showed highest DMC of 8.69 and 8.20 log10/ml among 12 isolates and used in further studies. Initial 6 log viable count of Listeria grayi L13 and Listeria seeligeri L14 in sterile skim milk reached to 8.00 and 8.58 log10cfu/ml with 0.64 and 0.62 %LA; protein of 1.00 and 1.62 respectively whereas L14 produced haemolysin of 9mm diameter at 24h of incubation at 37ºC. The viable cells of L13 and L14 were killed when the contaminated milk was subjected to pasteurization, boiling and sterilization. L13 and L14 when inoculated at 6 log counts into sterile whole milk and stored at 5°C, the raise in viable log count was 8.50 and 8.35 whereas titratable acidity reached to 0.19% and oleic acid to 1.28 and 1.24% while protein content declined to 1.00 and 1.36% respectively with storage period of 9 days.
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    ThesisItemOpen Access
    STUDY ON THE EFFICACY OF NISIN AS AN ANTIMICROBIAL AGENT IN PANEER PACKAGING MATERIAL
    (KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR –, 2021-07-01) MANU T. V.; RAMACHANDRA, B.
    The present study was aimed in increasing the shelf life of paneer by incorporating antibacterial agent nisin to the packaging material. TBC, Coliform, E. coli and Aerobic spores counts from packaging material were 1.01, 0.80, 0.81 and 0.87 log10 cfu/cm2 and in paneer samples TBC, Coliforms, Staph. aureus and Aerobic spores counts of 5.19, 3.60, 2.75 and 1.14 log10 cfu/g respectively. Packaging material isolates were identified as Klebsiella ozaenae, Citrobacter intermedius, E. coli and Bacillus cereus and Paneer isolates were identified as Micrococcus varians, Citrobacter intermedius, E. coli, Salmonella sp., Staph. aureus, and Bacillus cereus respectively. Micrococcus varians, Staph. aureus and Bacillus cereus showed maximum inhibitory area of 374.66, 184.00, 273.66 sq. mm at 200 ppm nisin. The inhibitory area obtained against Micrococcus varians we're 413.96, 454.45, 341.63 and 56.56 sq.mm; 188.52, 138.48, 74.63 and nil for Staph. aureus; 245.08, 188.52, 124.14 and 25.14 Sq.mm for Bacillus cereus at 200 ppm nisin of pH 2.6, 4.6, 6.6 and 8.6. Heat treated nisin for 85 ℃/30 min showed maximum inhibitory area of 274.25, 93.16, 138.83 sq. mm against Micrococcus varians, Staph. aureus and Bacillus cereus. Effect of nisin coated films with 50, 100, 150, 200 ppm soaking time on the survivability of the test organisms revealed that at 200 ppm, the percentage reduction was more which was about 86.2, 83.5, 83.0 percent for Micrococcus varians, Staph. aureus and Bacillus cereus. The 200 ppm nisin coated film packed paneer stored at refrigeration temperature (7±1 ˚C) found acceptable till 12th day during storage.
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    ThesisItemOpen Access
    INCIDENCE OF LISTERIA SPECIES FROM DAIRY ENVIRONMENTAL SAMPLES
    (KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2020-08-01) CHAITHRA S.; PRABHA R.
    In present study, Listeria count in soil, fodder, dung and feed samples collected from university dairy farm ranged from 2.30 to 3.14 log10cfu/g. Udder swab, pail rinse, pail milk and can milk had Listeria count of 0.30 log count while 0.60 log count observed in chilled milk whereas water, swabs of hand, udder and equipment, pail and can rinses, aseptic milk and pasteurized milk did not show the presence of Listeria. Among 23 isolates of Listeria obtained from dairy environmental samples, Listeria monocytogenes predominated (56.50) followed by Listeria innocua (17.39), Listeria ivanovii (8.70); Listeria seeligeri (4.35) and 13.06 per cent of unidentified Listeria sp. All the 23 Listeria isolates, except L. monocytogenes L16 grew well at 5 C indicating psychrotrophic nature of the isolates. At deep freeze temperature (-18 C), only 9 out of 23 Listeria isolates showed growth indicating the psychrophilic nature of isolates. Among 23 Listeria isolates, 14 numbers of Listeria spp. showed haemolysis, phospholipase and coagulase activities indicating pathogenic nature. Listeria monocytogenes L10 showed highest DMC of 8.95 log10/ml among 23 isolates and used in further studies. Initial viable log count of Listeria monocytogenes L10 in sterile milk 5.95 reached to 8.98 with per cents of 0.30 LA; protein of 1.00, oleic acid of 1.86 and haemolysin of 10 mm diameter at 24 h of incubation at 37 C. L. monocytognes L10 at 3, 4, 5 and 6 viable log counts inoculated into sterile whole milk and stored at 5 C the raise on an average viable log count was by 4, 3, 2 and 1.5 with storage period of 30, 20, 12 and 9 days, respectively based on the curdling of milk. During storage, the percent mean acidity of 0.23, protein reduction by 1.25, developed oleic acid was 1.40. Haemolysin production in L. monocytognes L10 started on half of storage period that reached peak on last day of storage at 5 C.
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    ThesisItemOpen Access
    ANTIBACTERIAL AND ANTIOXIDANT PROPERTIES OF CHAKKA WHEY BASED BEVERAGE
    (KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2019-08-01) THUPAKULA SARASWATHI; RAMACHADRA, B.
    The present study was aimed to utilization of chakka whey obtained from chakka using Lactococcus lactis ssp. lactis, yoghurt culture Streptococcus thermophilus and Lactobacillus delbreuckii ssp. bulgaricus, Befidobacterium sp. These cultures were used separately and in combination for the preparation of chakka. The chakka whey beverages added with different levels of sugar at 5, 7.5 and 10 per cent. At the 7.5 per cent sugar level, the chakka whey beverage prepared from chakka whey obtained from chakka using yoghurt culture was found to be best among the other cultures. In case of antibacterial activity of chakka whey and its beverage, there was no antibacterial activity against E.coli and Salmonella sp. But, the antibacterial activity against the test organism Stap.aureus were 11.78 , 12.10, 13.0 and 12.5 sq.mm for chakka whey beverage prepared from chakka whey obtained from chakka using Lactococcus lactis ssp. lactis, yoghurt culture, Bifidobacterium sp. and in the combined cultures respectively. The antioxidant activity (% DPPH) of chakka whey, beverage and their fractions of supernatant and CFE obtained using Lactococcus lactis ssp. lactis were 18.03, 24.03, and 43.8. Similarly chakka whey beverage, their fractions of supernatant and CFE obtained using yoghurt culture, Bifidobacterium sp. were 61.72, 47.36, 70.49 and 61.41, 53.06, 61.40 respectively, whereas in case of chakka whey beverage prepared from chakka whey obtained from chakka using combined cultures it was 35.2, 35, 54.30. The effect of heating on antioxidant activity (% DPPH) of chakka whey beverages at control, pasteurization, 85oC/30 min, boiling and sterilization temperatures showed 70.49, 49.33, 32.85, 19.1 and negative values respectively. The altered pH values of chakka whey beverages at control 2, 3, 4, 5, 6, 8 and 9 had 70.49, 84.5, 80.5, 60.5, 58, 20, 13, 11 and 8.0 (% DPPH) antioxidant activity respectively. The characterized crude whey protein obtained on dialysis of whey beverage had 4.9 pH, 0.20 acidity (Lactic acid) per cent, Further, heating of whey proteins at 80oC for 5 min had lost 20 per cent whey proteins. And the antioxidant activity of dialysed whey proteins at 1:10 dilution was 36.8 (% DPPH), 12.5 Sq.mm antibacterial activity against the Stap.aureus. The optimized chakka whey beverages prepared from whey obtained from chakka using yoghurt culture was stored at refrigeration temperature (7±1oC) and was found acceptable till 12th day at refrigeration temperature respectively.
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    ThesisItemOpen Access
    MICROBIOLOGICAL CHARACTERISTICS OF KUMISS PRODUCED FROM COW’S MILK
    (KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 0007-07-01) SHIVARAJ SHIVASHIMPAR; RAMACHANDRA, B.
    Kumiss is an effervescent acidic, alcoholic fermented, milky white or greyish liquid made primarily from mare’s milk. Kumiss has health benefits as it contains prebiotics like inulin. It is limited to the places like central Asia, Russia, Eastern Europe etc. due to its limited technological information and unavailability of mare’s milk and Kumiss as a product itself in certain parts of the world. In the present study an attempt was made to prepare Kumiss from cow’s milk. The lactic isolates like lactococcus lactis ssp. lactis, Leuconostoc mesenteroides ssp. mesenteroides, Lactobacillus delbreuckii ssp. bulgaricus, Streptococcus thermophilus and yeast Kluveromyces lactis were isolated from the domestic dahi samples. During the preparation of Kumiss parameters like types of milk, lactose content of cow’s milk, heat treatments, inoculum levels and incubation periods were studied. Finally, cow’s milk was made enriched with lactose to the level of 6.1% to simulate mare’s milk lactose composition as lactose is a crucial component for the acid and alcohol production. The milk was heated to 900 C/5 min and inoculated with 10% LAB + 20% LFY separately for a period of 48 h. at 300C in an orbital shaking incubator for better alcohol production. A final cow’s milk Kumiss was produced with 0.89% alcohol and 0.85% LA. The stored cow’s milk Kumiss had 4 days shelf-life at room temperature (27±10C) with the acidity of (1.35% LA), alcohol (0.70%), viable count (6.72 log10cfu/ml) and 9 days shelf life at refrigeration temperature (6±10C) with the acidity (0.94%LA), alcohol (0.74%), viable count (6.1 log10cfu/ml) respectively.
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    ThesisItemOpen Access
    INCIDENCE OF LISTERIA SPECIES FROM DAIRY ENVIRONMENTAL SAMPLES
    (KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2020-08) CHAITHRA S.; Dr. PRABHA R.
    In present study, Listeria count in soil, fodder, dung and feed samples collected from university dairy farm ranged from 2.30 to 3.14 log10cfu/g. Udder swab, pail rinse, pail milk and can milk had Listeria count of 0.30 log count while 0.60 log count observed in chilled milk whereas water, swabs of hand, udder and equipment, pail and can rinses, aseptic milk and pasteurized milk did not show the presence of Listeria. Among 23 isolates of Listeria obtained from dairy environmental samples, Listeria monocytogenes predominated (56.50) followed by Listeria innocua (17.39), Listeria ivanovii (8.70); Listeria seeligeri (4.35) and 13.06 per cent of unidentified Listeria sp. All the 23 Listeria isolates, except L. monocytogenes L16 grew well at 5 °C indicating psychrotrophic nature of the isolates. At deep freeze temperature (-18 °C), only 9 out of 23 Listeria isolates showed growth indicating the psychrophilic nature of isolates. Among 23 Listeria isolates, 14 numbers of Listeria spp. showed haemolysis, phospholipase and coagulase activities indicating pathogenic nature. Listeria monocytogenes L10 showed highest DMC of 8.95 log10/ml among 23 isolates and used in further studies. Initial viable log count of Listeria monocytogenes L10 in sterile milk 5.95 reached to 8.98 with per cents of 0.30 LA; protein of 1.00, oleic acid of 1.86 and haemolysin of 10 mm diameter at 24 h of incubation at 37 °C. L. monocytognes L10 at 3, 4, 5 and 6 viable log counts inoculated into sterile whole milk and stored at 5 °C the raise on an average viable log count was by 4, 3, 2 and 1.5 with storage period of 30, 20, 12 and 9 days, respectively based on the curdling of milk. During storage, the percent mean acidity of 0.23, protein reduction by 1.25, developed oleic acid was 1.40. Haemolysin production in L. monocytognes L10 started on half of storage period that reached peak on last day of storage at 5 °C