Quality evaluation in storage of aonla (Emblica officinalis Gaertn.) juice extracted from fruits preserved by steeping in water

Aonla (Emblica officinalis Gaertn.) fruits are preserved either in water or salt solution for a couple of weeks for the commercial preparation of products. In the present study, quality of aonla (cv. Chakaiya) juice prepared from fruits steep preserved in water for 30 days was assessed during storage up to 9 months under ambient conditions. The juice was prepared from fruits withdrawn at 0, 5, 10, 15, 20 and 30 days of steeping preservation in water, pasteurized at 90°C and preserved with 500 ppm SO2 in glass bottles under ambient conditions. A continuous decrease in TSS (6.7 to 2.6 °B), titratable acidity (1.52 to 0.48%), ascorbic acid (292.0 to 36.5 mg/100 g) and polyphenols (1.32 to 0.76%) were observed in fruits with the prolongation of steeping period. The retention of nutrients was better up to 10 days of fruit preservation, thereafter a sharp decline in nutrients was noticed. Subsequently, the quality of extracted juice was also deteriorated significantly as the steeping preservation of fruits in water prolonged. The contents of ascorbic acid and polyphenols in fresh juice decreased from 309 to 43 mg/100 ml and 3.09 to 0.57 per cent, respectively, when extracted from fruits after 30 days of steeping preservation. In juice, prepared from fruits steep preserved for more than 10 days, the decline in nutritional quality was more pronounced. The quality parameters in juice deteriorated further upon 9 months of storage. The retention of ascorbic acid in juice was found to be around 50 per cent after 4 months of storage when prepared from fresh and 10 days steep preserved fruits. Though polyphenols decreased significantly in juice during storage up to 9 months, the loss was minimum (less than 20%) up to 4 months. TSS and titratable acidity did not change significantly during storage of juice though found slightly reduced. Non-enzymatic browning (NEB) was also minimum (0.040 OD) during initial period of juice storage (up to 4 months). The study indicated that juice extracted from aonla fruits steep preserved in water up to 10 days could retain maximum quality up to 4 months of storage under ambient conditions.