Effect of Piper guineensees on physicochemical and organoleptic properties of watermelon (Citrulus lanatus) juice stored in refrigerator and ambient

Abstract

Extracted juice from watermelon containing 0.01gPiper guineensesstored in refrigerator (6±2 ^oC) and on the shelf (28±1^oC) usingpolyethylene bottles was evaluated for physicochemical and organoleptic changes. pH, total soluble sugars, titratable acidity and organolepticevaluation of the juice was carried out till deterioration sets in. Results showed that the sample stored in therefrigerator kept for 7 days while the sample on the shelf lasted for 3 days. pH value decreased from 5.40 to 4.80 and 5.70 for the samplestored in the refrigerator and on the shelf respectively while TSS increased from 0.064%Brix to 0.435% Brix and 0.578%Brix for sample stored in refrigerator and shelf respectively. Titratable acidity decreased from 2.90 % to 0.20% and 0.50% for samples for the juice stored in the refrigerator and on shelf respectively.All these changes were statistically significant (p<0.05).The sample stored on the shelf lost its organoleptic qualities on the third day with an average value less than 2 for taste, smell and colour. However, the juice stored in the fridge lost its organoleptic qualities at the 7^th day with an average value of 3.0, 2.90 and 2.80 for taste, smell andcolour respectively.  From the results, juice extracted from water meloncannot be kept at ambient temperature beyond 3 days without proper refrigeration and an additive. This calls for alternative way of extending its shelf life in the absence of electricity supply using local spice like P. guineenses and to make it available during off season.