Richa SalwanAnanya Sharma2024-10-052024-10-052024-09-28https://krishikosh.egranth.ac.in/handle/1/5810215401The present study involves the development of probiotic based mango and carrot blended beverage to ensure consistency, quality and health benefits. Lactic acid bacteria (LAB) were isolated from home-made curd samples on deMan Ragosa and Sharpe agar (MRSA). Based on morphological characteristics, 3 different isolates were purified and maintained at 4 ℃ and -20 ℃ in skim milk and 30% glycerol, respectively. LAB isolates were found Gram positive, catalase negative and non-motile and were able to grow between 10-40 ℃, 2-8 pH, and 0.5 to 2% NaCl. Screening for probiotic attributes showed survival of LAB isolates under simulated gastrointestinal conditions and bile salt tolerance, antimicrobial activity, Galactosidase activity and exopolysaccharide production. Among all, promising isolate 3A was identified as Lactobacilus delbrueckii based on 16S rRNA gene sequencing. Lactobacilus delbrueckii 3A containing 1011-1012 CFU/ml was introduced in the best formulation containing a blend of 4 parts of mango and 2 parts of carrot with 40% of water and incubated at 37 ℃ for 24 h which was maintained as pre-inoculum. Central composite design based on response surface methodology was applied to optimize temperature, incubation time and inoculum concentration to obtain enhanced flavour, and nutritional properties of the beverage. Optimization revealed 25 ℃, 24 h incubation period and 0.75% inoculum as best conditions for maintaining sensory and nutritional properties viz., antioxidants, ascorbic acid, carotenoids, and total phenolics in juice. Sensory evaluation revealed overall acceptability with appealing taste, flavour and colour of probiotic based mango and carrot blended beverage. FTIR based absorption spectra revealed spectra bands corresponding to carboxylic acid, aromatic compounds, C=O acid stretching, and C-O and CC bonds in probiotic beverage compared to control. GC-MS results revealed the occurrence of compounds contributing as flavour volatiles, also impacting overall aroma. The shelf life of probiotic based beverage was studied in glass and PET bottles under refrigeration and room temperature. The results revealed significant changes in physico-chemical in pH, acidity and TSS, indicating successful fermentation in the beverage. Although changes occurred in nutritional parameters including antioxidants, carotenoids, phenolics and ascorbic acid during storage, but remained consistent in glass bottles under refrigeration till 60 days. Quality analysis showed maintenance of 7 log CFU/ml which meets FSSAI Specification, 2022 for probiotic products. No yeasts and moulds and coliform count was detected in probiotic beverage, hence indicating safe for human consumption. The production cost for 200 ml of probiotic juice remained Rs 83.29/- in glass bottles and Rs. 80.89 in PET bottles. The findings contribute to growing field of functional foods, offering a tasty and nutritious option for improving gut health and overall wellbeing.EnglishThesis