PhD

Cocoa is the sole source for chocolate and its manufacture continued to be the monopoly of multinational companies. Even though, cocoa is mainly grown in small-holder sector, the growers are forced to sell their produce at a price decided by the multinational companies. The growers are facing acute problem due to ineffective procurement system of the companies and the unrealistic price offered by them. In this context, development of viable technologies for small-scale processing and value addition of cocoa will help a long way to safe guard the interest of farmers (Amma et al., 2004). Hence the present study was taken up with the objectives of standardization of primary and secondary processing of cocoa for small scale unit and the development of an Instant Chocolate Beverage Powder (ICBP) and studying its suitability for preparation of value added products.

The primary processing technology for cocoa was standardised in terms of fermentation, drying and storage of cured beans. Pod storage for four days was found to produce quality beans during the major (April- May) as well as minor (Sept- Oct.) harvest seasons of cocoa. The application of pectinase (0.01per cent) enhanced the effectiveness of fermentation as reported by Bhumibhamon and Jinda (1997). The quality analysis of sun dried and oven dried beans revealed the superiority of sun dried beans over the other. The most desirable pH (5.82-5.84) of the beans was achieved in sun dried samples. The effectiveness of fermentation and drying as judged by the cut test (Wood and Lass, 1985) revealed the superiority of selected fermentation and drying treatments. Packaging and storing the beans in jute bag with double lining of polythene was found to retain quality of beans to an acceptable level upto ten months during both the seasons.

The secondary processing of cocoa (alkalisation, roasting and grinding) was standardised for small scale units. Alkalising the cured beans with one per cent Sodium carbonate for four hours was found beneficial. The chocolate prepared using alkalised beans was ranked superior with respect to pH and sensory attributes. Grading the beans based on size before roasting is to be done to get good quality powder and butter. Large sized beans (1.2 g) gave better quality powder compared to that of small and medium sized beans. The quality of beans roasted in shallow pans was superior compared to that roasted in small scale roaster. The ideal duration for grinding the roasted beans was identified as four to six hours when a table top grinder of two litre capacity (suitable for small scale unit) was used.

A value added product viz., ICBP was developed adopting the technology of spray and cabinet drying. The ideal inlet/ outlet temperature for production of quality ICBP was standardized as 190/900 C for spray drying and the feed composition formulated with 14 per cent cocoa, 63 per cent milk solids and 23 per cent additives produced the best quality ICBP. The quality of the spray dried powder was better than that of cabinet dried samples. In addition to the suitability for preparation of beverage, the ICBP was found useful as a base material for preparation of chocolate, shake and pudding.