Process optimization for the preparation of apple tea wine with analysis of its sensory and physico-chemical characteristics and antimicrobial activity against food-borne pathogens

DOI 10.17470/NF-016-1030-2

Vikas Kumar, Vinod K Joshi, Gitanjali Vyas, N.S. Thakur, Nivedita Sharma

Method for preparing apple tea wine using different types of tea at different concentrations were optimized and the physico-chemical, antimicrobial and sensory characteristics of the wine analysed. All characteristics were found to be directly proportional to the concentration of tea fermented naturally or with Saccharomyces cerevisiae var. ellipsoideus. In both types of fermentation, CTC (crush, tear and curl) tea-based apple tea wine received significantly higher quality scores (p≤0.05). Better results in terms of ethanol, higher alcohol concentrations and antimicrobial activity were found with 4 g tea/100 ml apple juice than with other concentrations, particularly 5 g tea/100 ml apple juice. All apple tea wines showed antimicrobial activity (inhibition zone >7 mm) against Escherichia coli (IGMC), Enterococcus faecalis (MTCC 2729), Listeria monocytogenes (MTCC 839), Staphylococcus aureus (MRSA 252) and Bacillus cereus (CRI). Apple tea wine fermented with S. cerevisiae var. ellipsoideus had higher sensory scores for most attributes than naturally fermented apple tea wine. Different treatments were clustered based on tea concentration as a function of fermentation with S. cerevisiae var. ellipsoideus unlike the natural fermentation where no clear clustering trend was observed. The type of fermentation influenced the quality of the wine as separate clusters for the different fermentations were observed during combined cluster analysis of the different types of wine. Our results demonstrated that the best apple tea wine was made with 4 g CTC tea/100 ml apple juice and fermented with S. cerevisiae var. ellipsoideus, and showed potential as a functional product which also demonstrates the medicinal properties of tea.