MSc

Jackfruit, a tropical composite fruit with delicious, succulent bulbs, is rich in carbohydrates, protein, potassium, calcium, iron, vitamin A, B, and C. The huge size and high perishability are major bottlenecks in its post harvest handling. As a result of the recognition that jackfruit is under-utilised but has considerable potential for alleviating malnutrition and income generation, appropriate methods for post harvest handling, processing and product diversification are to be developed.
In this circumstance, a study on “Development, packaging and storage of intermediate moisture jackfruit (Artocarpus heterophyllus L.) was conducted in the Department of Processing Technology, College of Horticulture, Vellanikkara. Intermediate Moisture (IM) foods are semi moist foods having ideal water activity between 0.65-0.90 and some of their water is bound by glycerol, sorbitol, salt or certain organic acids, thus preventing the growth of many micro organisms. As the intermediate moisture products are characterized by semi moist consistency, these foods have enough moisture content to permit easy chewing but low enough water to prevent spoilage.
Firm, ripe bulbs of variety Muttam Varikka were subjected to additive infusion by steeping in a solution containing a binding agent (2%) in combination with a humectant (sucrose-60%), an antioxidant (ascorbic acid-0.2%) and a preservative (potassium metabisulphite-0.2%), for 12 hours. The binding agents used were calcium lactate, sodium alginate, corn starch and cassava starch. After additive infusion, the bulbs were dehydrated in a drier developed by the NIST, Thiruvananthapuram at three different temperatures viz 40±5, 50±5 and 60±5°C.
Moisture content and water activity were found to be in the range of 16.20 to 22.54 per cent and 0.76 to 0.80, respectively. Moisture content, water activity, pH, vitamin C, total carotenoids, total flavanoids and microbial count showed a
declining trend with increase in dehydration temperature. TSS, titratable acidity and sugar content increased with increase in dehydration temperature. Observations on physico chemical characteristics revealed significant differences only in pH and vitamin C content of the product. Therefore, the treatment possessing maximum organoleptic quality and minimum microbial load was selected as the best one. Thus intermediate moisture jackfruit containing corn starch as the matrix binding agent in combiantion with other additives was selected for storage studies
The intermediate moisture jackfruit thus developed was enclosed in seven types of packaging materials (LDPE 200 gauge, plastic trays over wrapped with cling film, high impact polystyrene boxes (HIPS), laminated aluminium foil pouches, rigid plastic boxes and glass containers) followed by storage under two conditions (ambient and low temperature).
Samples stored under ambient conditions became unmarketable after two months of storage, whereas the ones stored under refrigerated condition was marketable upto six months. LDPE pouches (100 gauge) and glass containers showed minimum changes in physico-chemical characteristics of the product as compared to other packaging materials.
A declining trend in moisture, water activity, pH, non reducing sugar, vitamin C, total carotenoids and total flavanoids was observed during storage, whereas TSS, acidity, total ash, reducing sugar, total sugar and non enzymatic browning showed an increasing trend. Organoleptic quality declined gradually during storage, but the scores were within the acceptable range in refrigerated samples.