To study the expression pattern of carotenoid biosynthetic pathway genes, changes in their expression at different stages of maturity in tomato fruit (cv. Arka Ahuti) were investigated. The genes regulating carotenoid production were quantified by a dot blot method using a DIG (dioxigenin) labelling and detection kit. The results revealed that there was an increase in the levels of upstream genes of the carotenoid biosynthetic pathway such as 1-deoxy-d-xylulose-5-phosphate reductoisomerase (DXR), 4-hydroxy-3-methyl-but-2-enyl diphosphate reductase (Lyt B), phytoene synthase (PSY), phytoene desaturase (PDS) and ζ-carotene desaturase (ZDS) by 2-4 fold at the breaker stage as compared to leaf. The lycopene and β-carotene content was analyzed by HPLC at different stages of maturity. The lycopene (15.33 ± 0.24 mg per 100 g) and β-carotene (10.37 ± 0.46 mg per 100 g) content were found to be highest at 5 days post-breaker and 10 days post-breaker stage, respectively. The lycopene accumulation pattern also coincided with the color values at different stages of maturity. These studies may provide insight into devising gene-based strategies for enhancing carotenoid accumulation in tomato fruits.

Roasted groundnut seeds, amaranth and dates pulp formed the center filling which was coated with sugar, breadings, desiccated coconut and roasted Bengalgram flour (BGF) to get 4 coated snacks. Physicochemical characteristics, microbiological profile, sorption behaviour and sensory quality of 4 coated snacks were determined. Centre filling to coating ratio of the products were in the range of 3:2-7:1, the product having BGF coating had the thinnest coating. Center filling had soft texture and the moisture content was 10.2-16.2% coating had lower moisture content (4.4-8.6%) except for Bengal gram coating, which had 11.1% moisture. Sugar coated snack has lowest fat (11.6%) and protein (7.2%) contents. Desiccated coconut coated snack has highest fat (25.4%) and Bengal gram flour coated snack had highest protein content (15.4%). Sorption studies showed that the coated snack had critical moisture content of 11.2-13.5%. The products were moisture sensitive and hence require packaging in films having higher moisture barrier property. In freshly prepared snacks coliforms, yeast and mold were absent. Mesophillic aerobes count did not show significant change during 90 days of storage at 27°C and 37°C. Sensory analysis showed that products had a unique texture due to combined effect of fairly hard coating and soft center. Flavour and overall quality of all the products were rated as very good.