Development of Composite Flour Biscuits and Quality Evaluation

Abstract

The present study was undertaken to develop nutritious biscuits from the composite flours. Composite flours were prepared by blending wheat flour with rice fl.our, mung flour and potato flour in ratios of 100:0:0:0, 85:5:5:5, 70:10:10:10 and 55:15:15:15, respectively and packaged in glass jar, high density polyethylene and aluminium flexible packaging for biscuits development. The physico-chemical properties (moisture, protein, fat, ash, pH, acidity and browning index) and functional properties (swelling capacity, water absorption capacity, oil absorption capacity, emulsion activity, emulsion stability, foam capacity, foam stability, least gelation concentration, gelatinization temperature and bulk density) of composite as well as other flours were determined using standard procedures. The standardized formulations for biscuit had ingredients as 100 g flour, 45 g sugar; 45 g hydrogenated fat, 1.25 g sodium bicarbonate, 1.25 g baking powder and 1.0 g curry leave powder. The biscuits were baked in convective baking oven at 1800C for 10-15 min till baked. The well baked biscuits were removed from the oven, cooled to room temperature, packaged and stored under ambient condition. The physico-chemical quality (moisture, protein, fat, ash, pH, acidity and browning index), microbial quality (Standard plate count, yeast and mold count) and sensorial attributes (color, taste, flavor, texture, crispiness and overall acceptability) of biscuits were analyzed just after preparation and during storage of 30, 60 and 90 days under ambient condition packaged in glass jar (GJ), high density polyethylene (HDPE) and aluminium flexible packaging (AFP). All the data of study were also statistically analyzed by using factorial Randomized Block Design (RBD) with the help of OPSTAT software. The physico-chemical properties wheat and composite flours viz., moisture content, protein, fat, ash, pH and browning index observed and increased whereas acidity decreased significantly with increase in the incorporation of rice, green gram and potato flour with wheat flour at ps0.05 level of significance. The functional properties of individual and composite flours such as swelling capacity, water absorption capacity, oil absorption capacity, emulsion activity, emulsion stability, foam capacity, foam stability, gelatinization temperature, least gelation concentration and bulk density were increased with increase in the incorporation of other flours with wheat flour. Overall acceptability for composite flour biscuits was awarded highest score for Wss followed by W1o and Was as compared to control biscuits. All biscuits coincided in the range of 'like moderately' to 'like very much' for composite flours biscuits while 'like slightly' to like moderately' for control biscuits. Highest overall acceptability was observed for Wss in AFP (7.61) and lowest for control biscuits in HDPE (6.72) at 90 days of storage. Sensorial data revealed that overall acceptability (OAA) of composite biscuits increased with increasing in the incorporation of rice, green gram and potato flour with wheat flour in the formulation of biscuits. Overall acceptability was decreased with increasing storage period irrespective of packaging materials. In general, Overall acceptability of biscuits depends on the individual data of different sensory attributes like colour, flavor, taste, crispiness and texture. The present study revealed that the composite flour biscuit (Wss) containing wheat flour (55%) + rice flour (15%) + green gram flour (15%) + potato flour (15%) was observed richest in fat and protein content along with higher overall sensory score packaged in Aluminium flexible packaging (AFP) during storage of 90 days. Other combination of composite flour biscuits (W1o and Was) and wheat flour were also acceptable after 90 days of storage in HDPE and glass jar.