EFFECTS OF BLANCHING AND VACUUM IMPREGNATION ON PHYSICOCHEMICAL AND SENSORY PROPERTIES OF INDIAN GOOSEBERRY (PHYLLANTHUS EMBLICA L.)

Vacuum impregnation (VI) was employed for development of minimally processed Indian gooseberry. Blanching of the fruits at different temperatures (70–90C) and times (20–60 s) was studied, and the process combination of 90C and 60 s was chosen as the most suitable for inactivation of peroxidase (POD) and maintaining stability of the fruit's color. Also, increase in both blanching temperature and time could significantly (P ≤ 0.05) reduce POD activity and result in blanched samples with higher yellowness. When the blanched fruits were osmotically dehydrated under vacuum pressure (6.8–13.5 kPa) and with osmotic solution of sucrose (mixed with honey) of 30–50°Brix, the most suitable parameters for VI of Indian gooseberry were chosen as 13.5 kPa and 50°Brix. Substantial reduction of water but increased content of carbohydrate and total soluble solids were obtained for the VI fruits compared with the fresh ones. PRACTICAL APPLICATIONS This study is aiming as being a useful and practical guide for the development of a new minimally processed product that is not only economically feasible but also of a high nutritional and medicinal quality for Thai consumers. The Indian gooseberry, being very highly astringent, was preserved firstly by water blanching and followed by a combination of vacuum impregnation and osmotic dehydration in order to achieve a fast and slight sugar gain, thus excluding the requirements of thermal treatment (during drying) and the addition of chemical preservatives. Additionally, this gain of sugar (sucrose) together with honey improves the preservation conditions and the sensory characteristics of the final product and allows us to successfully develop a preserved fruit which is highly recognized for its health benefits.