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Researcher Sukhvir
Advisor Kocher, Gurvinder Singh
Source KrishiKosh-Indian National Agricultural Research System
Content type Text
Educational Degree Master of Science (M.Sc.)
Publisher Punjab Agricultural University
File Format PDF
Language English
Subject Domain (in DDC) Natural sciences & mathematics ♦ Life sciences; biology ♦ Microorganisms, fungi & algae
Subject Keyword Cider ♦ Polyphenols ♦ Tannins ♦ Apple Wine ♦ Malolactic ♦ Evaluation of Apple Cultivars For Fermentative Production of Cider ♦ Microbiology ♦ Fermentative Production of Cider
Abstract Two apple cultivars (Red delicious and Golden delicious) were evaluated in terms of physicochemical characteristics were found to be optimum in terms of Brix, acidity, polyphenols, tannins for processing into cider production. Apple skin, a reservoir of diverse microflora, provided two morphologically distinct yeast isolates A2 and A3. Growth kinetics and fermentative performance evaluation of six yeast strains [S. cerevisiae MTCC 11815, S. cerevisiae NRRL Y-2034, apple isolates A2, A3, Candida ethanolica H3 (a grape isolate) and a commercial strain S. cerevisiae D7] led to selection of D7 and A2 for ethanolic fermentation optimization. Yeast isolate A2 showed maximum growth, sugar uptake rate (2.99 g/g) and ethanol yield [11.53% (v/v)] on chaptalized apple juice. A2 was molecularly identified on the basis of 18s rDNA sequencing that showed a 100% match with S. cerevisiae KU218475.1 and was named as S. cerevisiae strain KY069279. Ethanolic fermentation optimization opting Response Surface Methodology revealed a temperature of 20ËšC, an inoculum size of 7.08 and 6.74 (%v/v) of S. cerevisiae KY069279 and D7, respectively and DAHP supplementation at 154.4 and 113.7 mg/100ml (for respective yeast strains) as optimum for apple cider production. Optimized parameters were validated successfully with fermentation efficiencies of 99.65 and 95.83% in both yeast strains viz. S. cerevisiae D7 and S. cerevisiae KY069279, respectively. Different sugar concentrations (12.5, 15 and 17.5ËšB) were evaluated for apple cider production whereby 15ËšB produced an ethanol level of 7.75 and 7.33% (v/v) for D7 and KY069279 and was optimized for apple cider production. Apple cider and apple wine production were scaled upto 5L and 50L that led to ethanol production of 7.2-7.54 (%v/v) for apple cider 10.7-10.9 (%v/v). Fresh apple wine produced from two yeast strains S. cerevisiae D7 and S. cerevisiae KY069279 having malic acid content of 1.10 and 1.87 (g/L), respectively subjected to malolactic fermentation (MLF) at already optimized conditions showed a declined range of 0.4 and 0.6 g/L of malic acid content in 6 days of MLF. Shelf life studies revealed that apple cider and wine samples retained their quality parameters over a period of 180 days and sensory analysis by a panel of 10 semi-trained panelists categorized the ciders prepared from KY069279 and D7 as of superior quality with the mean scores of 69 and 67.5, respectively. Apple wine was also classified into superior wine category with sensory scores of 74.5 and 73.5 for KY069279 and D7, respectively.
Educational Use Research
Education Level UG and PG
Learning Resource Type Thesis
Publisher Place Ludhiana
Size (in Bytes) 4.02 MB
Page Count 86