PhD

The jackfruit (Artocarpus hetrophyllus Lam.) a member of the Moraceae family is an important fruit in India and is grown sporadically in other parts of the tropics mostly as a dooryard tree. Jackfruit indigenous to India is the single largest edible fruit and is a heavy yielder than other fruit trees. Among the fruits grown in Kerala, jackfruit tops the list in terms of production (28.9 lakh tonnes). Inspite of this huge production no serious efforts has been taken up so far to utilize this plentiful resource into effective commercial exploitation for the manufacture of value added food products. Hence the present investigation entitled “Utilization of jackfruit for product development and by-product recovery” was taken up to develop diversified food products applying innovative and indigenous technologies and to explore the possibility of by-product recovery from the waste generated after jackfruit processing.
The study comprises in depth analysis of the physico-chemical characteristics of the two varieties of jackfruit, product development utilizing fruit pulp and seed flour, chemical, nutritional, organoleptic and shelf life assessment of the products developed. Consumer acceptance and consumer preference of the products, economic viability and comparison with the food quality requirements were other aspects studied in order to ascertain commercial viability of the products developed.
Products developed under the present investigation are clarified juice, jackfruit nectar and jackfruit bars from the two varieties of jackfruit. Seed flour products such as health drink mixes, bakery and confectionary products are the other products standardized. By-products, viz., pectin and starch were extracted from jackfruit waste and its quality evaluation was ascertained.
Physico-chemical characteristics of jackfruit bulbs and seeds revealed that, varietal difference was reflected in weight and length of fruits and yield per plant and fruit per plant, which was in favour of koozha variety. Fruit bulbs and seeds were also heavier and more for koozha variety as compared to varikka. However, bulbs were more attractive in varikka fruits and was more suitable for product development. Chemical and nutritional characteristics analysed in the jackfruit bulbs of the two varieties revealed significant difference in total soluble solids, total sugars, reducing sugars, -carotene, pectin and polyphenols. Assessment of jackfruit seeds indicate higher moisture, acidity, total sugar and reducing sugar in koozha seeds.
Clarified juice extracted from varikka jackfruit pulp by enzymatic treatment gave 30 per cent higher juice yield, and was found to have pH 5.6, 2.05 per cent acidity with a total soluble solids of 15.03 Brix. The juice was sparkling clear with negligible browning.
Fruit nectars were standardized from two varieties of jackfruit individually and by blending with other fruit pulps. Four nectars of different taste and flavour were formulated from each variety of jackfruit. Chemical characteristics of nectars indicated that varikka nectars were found to have higher acidity, total soluble solids, total sugar, reducing sugar and -carotene compared to koozha nectars standardized. Pineapple blended and mango blended nectar adjudged to be the best for taste and flavour, while papaya blended nectars were preferred for appearance and colour. The chemical and organoleptic characteristics of the nectars were found to change with storage but remained stable till 45 days. Nectars stored under refrigerated condition depicted lesser changes with respect to chemical and organoleptic features as compared to nectars stored under non-refrigerated condition. Nectars formulated from varikka pulp were found to be more acceptable as compared to koozha nectars. The overall acceptability of jackfruit nectars was found to range between 77 to 79 per cent.
In the present investigation, jackfruit bars were standardized individually and also by blending with other fruit pulps. As observed in fruit nectars, blending with papaya pulp enhanced the appearance of the fruit bars while blending with mango pulp resulted in better flavour, taste and overall acceptability. Six different fruit bars standardized were highly acceptable with an excellent percentage acceptability (82.00 per cent). Significant difference was also observed with respect to all the chemical constituents between the variety and the treatments applied. chemical and sensory features declined gradually with storage. The shelf stability of jackfruit bars recommended is five months in sealed laminated pouches.
The two health drink mixes standardized from seed flour were nutritionally rich and high in mineral content. Malted health drink was preferred to spiced health drink mix in sensory features, though both the mixes scored above 80 per cent for overall acceptability. Mixes were stable for five months and was encouraging to note that negligible decline was observed in nutrient content with storage.
Bakery and confectionary products developed from jackfruit seed flour was the most preferred products. Both the products were found to be nutrient rich and could be relished by different categories of people. It is worth mentioning that seed flour biscuits were less susceptible to deteriorative changes with storage. Shelf life suggested for biscuit is two months, while confectionary product, laddu is of short life (10 days) as expected.
Microbial contamination of all the products standardized was monitored at periodic intervals and was found to be negligible. Consumer acceptance and preference of the products revealed highest acceptance and preference for bakery and confectionary products followed by mango blended fruit bars, plain varikka nectar and pineapple blended nectar. Products developed from jackfruit pulp and seeds were compared with the available FPO and ISI standards and were found to be in accordance with the standards prescribed.
Cost of production and product yield was worked out, for all the products standardized and were found to be reasonable and comparable to the proprietary products available in the market. Taking into account of the cost factor, the jackfruit seed flour biscuit formulated in the present study are ideal, nutrient dense and comparable with proprietary products available in the market. Jackfruit nectars and fruit bars were found to be the cheapest.
By-products recovered from jackfruit waste under the present investigation are pectin and starch. Varikka fruit was found to be more ideal for extraction of pectin and starch as compared to koozha fruit. Quality characteristics of the by-product recovered were also in favour of varikka fruit. However, cost of recovery of pectin was found to be high while that of starch is reasonable.
Based on research findings following recommendations and conclusions could be drawn.
Both the varieties of jackfruit could be utilized for product development.
Technologies developed need to be transferred to the interested entrepreneurs and popularized.
Processing of jackfruit should be taken up at commercial level in order to avoid wastage during the glut season.
Modern packaging techniques and upscaling of the products is needed in order to enhance the shelf life and appeal of the products.
Product diversification with respect to raw jackfruit is to be attempted.
Jackfruit waste generated could be utilized for byproduct recovery and also for compost production in an ecofriendly manner.
The starch extracted from jackfruit can be exploited for use in textile, food, paper and pharmaceutical industries.
India has visualized the tremendous potential for commercial and export oriented agri-business. Exploitation of this potential can bring about an era of prosperity with the right mix of employment generation and profit.