Quality Evaluation of Enzyme Liquefied Papaya Juice Concentrate (PJC) Stored at Various Temperatures

Abstract

This paper aims to study the effect of storage on enzyme liquefied papaya juice concentrate. Papaya pulp was liquefied using pectinase enzyme for juice extraction. The enzyme liquefied juice was subjected to concentration process by adopting Single Effect Tubular Evaporator (SETE) at 50°C with 24 inches vacuum. The Papaya Juice Concentrate (PJC), 68°brix was packed in high density polyethylene (HDPE) jars (200 g capacity) by leaving one inch head space and packed PJC jars were stored at various temperatures such as room temperature (RT, 29±1°C), low temperature (LT, 4°C) and frozen storage temperature (FT, -18°C). The PJC samples were analyzed for physicochemical characteristics and microbial load at 15 days intervals using methods reported in the literature. During storage, the PJC samples stored at RT showed significant increase in L, a and b values and browning as compared to LT and FT, while slight change in carotenoid content was observed. At the end of one month storage, the microbial counts (colony-forming unit/g) like total plate counts, yeast and molds counts and Staphylococcus counts in the PJC samples were low and Escherichia coli was absent. The study showed that enzymatic liquefaction can be used for better juice extraction from papaya and PJC prepared from this juice was physicochemically and microbiologically stable at various temperatures for one month.