Production of Vinegar from Pear Juice and Comparative Analysis of its Quality with Apple Juice Vinegar

Abstract

Vinegars are the product of scalar fermentations carried out by several groups of microorganisms acting at different moments in time. Apple vinegar is made with apple juice or concentrated Apple juice (CAJ) through a double fermentation: alcoholic and acetic. Vinegar was successfully produced from the juice extracted from pear using yeast and acetic acid bacteria. This study presents a summary of research concerning the quality of vinegar made from pear and apples by using double distillation method. Juice is extracted from both the apple and pear and was analysed for several parameters like pH, brix, specific gravity, Total Reducing Sugars (TRS), Reducing Sugars (RS), titratable acidity, alcohol percentage and Total Dissolved Solids (TDS). pH of pear and apple juice was found to be 4.82 and 4.35 respectively. pear and apple juice had the Brix of 8.5° and 12° respectively. The TRS of pear and apple juice was found to be 10.2%and 11.87 % respectively. Quality characteristics between pear vinegar and apple vinegar were investigated which includes pH, titratable acidity and alcohol percentage. The alcohol percentage of pear vinegar is slightly less than apple vinegar but the titratable acidity of pear vinegar was slightly more as compared to apple vinegar. Also pH of pear vinegar and apple vinegar are found to be 3.60 was 3.58 respectively. Acetic acid bacteria were isolated from Pear and apple vinegar prepared, using Frateur medium and Glucose Yeast Peptone (GYP) agar medium. Aceto Acetic Bacteria (AAB) isolated was confirmed to be Gram negative rods through Grams staining. The study reveals that pears being a seasonal fruit and cheaper compared to apples can be used to prepare healthy vinegar of best quality by a simple double fermentation method.