EFFECTS OF JUICE CONTENT AND pH OF MUST ON THE QUALITY OF YACON (SMALLANTHUS SOCNCHIFOLIUS) WINE

Abstract

Yacon brought from Phaksib, Dhankuta was used for the preparation of yacon wine. The fruit was sorted, washed, disinfected peeled for juice extraction. Yacon juice was analyzed for TSS, acidity, reducing sugar, and pH. Yacon wines were prepared from nine musts using different proportion of juice content (100%, 50% and 25%) and pH (3, 3.5 and 4) maintaining constant TSS (25ºBx) with addition of sugar and pH of must were maintained with the help of citric acid. Fermentation was carried out at ambient temperature ranging 23-27ºC using baker yeast and aged for 3 months. Effect of juice content and pH on sensory attributes of the wines were evaluated using seven point Hedonic scale rating test to identify the best product. The data were analyzed by one-way and two-way ANOVA using Genstat (Genstat Discovery Edition 12, 2009) at 5% significance level. Sensory analysis showed that there was significant difference among all the products with respect to appearance, odor, in-mouth sensation, finish and overall acceptance. Variation in juice content and pH of must significantly (p<0.05) affected wine quality. From sensory evaluation wine prepared from 100% juice and pH of 3.5 was found to be superior and had 12.50 % (v/v) alcohol content, 9.2ºBx TSS, 3.40 pH, 0.376% (as % lactic acid) total acidity, 0.012% (as acetic acid) volatile acidity, 367 ppm ester and 317 ppm aldehyde. Alcohol content, volatile acidity and other parameters of wine were within the range of a good quality wine. The cost of wine prepared using 100% juice and pH of 3.5 was NRs.121 per 750 ml) and hence this wine had great potential for commercialization.