Studies on microwave drying and packaging of curry leaves

Abstract

The curry leaves (Murraya koenigii) a green leafy vegetable, is also been used as spice. Leaves are especially good sources of vitamin A, vitamin C, and folic acid vitamins most likely to be lacking in the diet. They impart health benefit by providing the much needed dietary essential minerals and vitamins to the human diet .The demand for fresh and dried curry leaves has considerably increased over the last two decades. Fresh green curry leaves contains about 75% water. They wilt and become inedible in a day or two without refrigeration. However, the post harvest and nutritional losses occur during handling, transportation, processing and storage, which have gone up to 40 per cent annually. When they are dried to less than 10 % water they remain good to eat for several months. Based on the above facts, an investigation was undertaken to study the effect of microwave drying of curry leaves and also to study its packaging. Fresh and mature curry leaves procured from market were subjected to three different drying methods namely;. sun drying, hot air oven drying and MW drying. The study involves mainly three steps: 1) drying studies and, 2) post drying analysis curry leaves, 3) packaging of dried curry leaves. The first major step involved is giving pre-treatments such as washing and blanching to the leaves. After that samples were by above stated methods. MW dried curry leaves reached the desired moisture content faster as expected. The second step involved the quality analysis of dried leaves in terms of moisture content, oil content, ascorbic acid, calcium and fibre content and also cooking quality through sensory evaluation. The oil content in the microwave dried samples were close to that of the fresh. Fibre content of the curry leaves were not affected by drying process, MW drying retain the vitamin c and calcium content without significant losses. It may be revealed from the results that the scores of the sambharam prepared by treatment P-40 and p-60 are superior. The MW oven dried curry leaves were filled and sealed in thee packaging materials such as Polypropylene(PP), Aluminium foil and LDPE. After quantitative analysis of the quality characteristics, it showed the curry leaves stored in LDPE packaging showed minimum loss of quality.