Development, nutritional evaluation and shelf life optimization of date-fructose Biscuit-Bar

Abstract

The demand of biscuits is increasing day by day, due to change in life style of people and convenient foods with improved formulations are making their way to market shelves. Proximate composition of different materials such as dates, peanuts and vetch protein isolate are found suitable for the preparation of DFBB. Sucrose, the main sweetener for biscuits bars could be replaced with fruit sugars that are more digestible and sweet with fewer calories. Low grade dates were used to prepare date-fructose (DF) by using enzyme assays. DFBB with 15% sucrose replacement with date fructose was found the best in terms of physical and sensory characteristics. For improving the protein quality of date-fructose biscuit bars, protein isolates from cheaper and locally available Indian vetch (Lathyrus sativus) were incorporated (IVPI).Sensory parameters especially color, taste, flavor and overall acceptability were affected with the replacement of IVPI and DF in DBB at different levels. 15% IVPI 15% DF replacement into DFBB did not affect the physical and sensory qualities. For 90 days shelf life study, levels of natural antioxidant extracts obtained from peanut peel and withania coagulans were optimized by using Response Surface Methodology (RSM). Optimized levels; 0.21% peanut peel and 0.32% withania coagulans extracts were found to provide the highest response in DFBB without affecting sensory characteristics during storage. Calorific value, free fatty acids and peroxide value,minerals content were non-significantly affected, while amino acids profile was greatly improved in DFBB. Biochemical serum profile and protein quality of the DFBB were evaluated through Spargue-Dawley rats studies. Biological value of BFBB was improved as a result of added IVPI. Serum electrolytes were affected non-significantly among groups. Lipid profile wasaffected significantly within diet groups, while study seasons remained non-significant. ALP, Bi.T, ALT, AST and blood glucose were significantly found lower as compared to control.No effect was observed on the in-vitro protein (IVPD) and starch digestibilities (IVSD). All the bars were acceptable with good sensory characteristics but bars containing medium level (0.5% of optimized combined levels of extracts) of antioxidant extracts were maximally preferred. DFBB achieved 3.53±0.4Kcal/gcalorific value. It was concluded that DFBB containing 15% Indian vetch protein isolate, 15% date fructose and 0.5% peanut peel and withania coagulans blended extracts were proved as the best biscuit bars having good sensory qualities and have 90 days shelf stability.