Development of low calorie, whole grain snacks using laboratory twin screw extruder

Research and development of high fiber, low calorie snack products from hulled rice, processed by Hermann Berstorff Laboratory Co-rotating Twin Screw Extruder 2 E 25*33D was conducted. Puffed hulled rice was mixed with roasted peanut, sesameseed or sunflowerseed; and pumpkin, corn or mungbean flake, and circularly shaped using gel binder. The result showed that two formulas of puffed hulled rice which were mixed with peanut and corn flake, had highest acceptability score. Cornflake added puffed rice obtained higher scores of appearance taste and acceptability than other formulas. However characteristic scores of all formulas were rather low and range of taste score was from 5.3-6.1 (neither like nor dislike-like slightly), while acceptability score was likely between 5.4-5.9. When proximate composition was determined, it was found that puffed rice mixed with pumpkin corn and mungbean flake contained lower calorie contents than oilseed mixed formulas. Calorie content of all formulas were ranged from 56.9-62.2 kcal/15 gram serving size. Sesame mixed hulled rice showed highest fiber content of 8.5 percent, the latter was mungbean mixed formula. For shelf life study, it was indicated that during 4 to 6 month storage, peroxide value (PV) of hulled rice mixed with peanut or cornflake, packed in four layers laminating bags (OPP, PE, aluminium. foil, LLDPE) were not changed, But PV of samples with peanut packed in two plastic bags (PP) for 4 months were increased from 2.38 to 13.7 meq/kg when kept until 6 months, it was increased to 19.07 meq/kg. At the period of 6 month storage, corn flake mixed hulled rice showed lower changes of PV than peanut mixed formula in either type of packaing materials. Moreover those formulas packed in laminating packages had PV and moisture content lower than packd in PP bags. Beside that development of polished rice addition to hulled rice was observed and 25 percent of polished rice by weight would be well accepted with good characteristics and acceptability more than other proportions.