Study of Selected Beverages with Β-Glucan from Oats and Barley on Physical Properties, Sensory Perception, Glycemic Index and Satiety

Abstract

Over recent years, more and more products with β-glucan have appeared in the market. This study was conducted to determine the physical, sensory evaluation and glycemic index (GI) of selected popular beverages with β-glucan in the Malaysian market, which were Biogrow Oat BG22 (from oats) and Biolife Barley BG25 (from barley). The physical parameters measured were colour, viscosity, and total suspended solid. Sensory analysis was conducted on 30 subjects using the 7-point hedonic scale. Attributes assessed were colour, aroma, viscosity, sweetness and overall acceptance. A total of 10 subjects were involved in the determination of GI value of these beverages. A total of 25 g glucose was used as the reference. Test meals also contained 25 g available carbohydrate and all beverages were mixed with 250 mL water. Blood samples (finger prick) were taken every 15 minutes (first hour) and 30 minutes (second hour) for the duration of 120 minutes after the food sample consumption. Test protocol was based on ISO26642:2010. Blood glucose values were determined using glucometer. A total of 30 subjects were chosen for the determination of satiety scores. Labelled magnitude satiety scale was used to measure satiety scores before and after test beverage consumption. Subjects were required to assess their perception of fullness or hunger by marking on the labelled magnitude satiety scale every 15 minutes for the first hour and 30 minutes for subsequent 2 hour for a total of 180 minutes. The colour analysis showed that BG25 and BG22 were slightly yellow due to positive b* value. The BG22 was more viscous and do not contain any sugar compared to BG25. Blood glucose level after glucose intake reached optimum level (9.9 mmol/L) at 30 minutes while BG25 and BG22 reached optimum level at 45 minutes with the value 7.9 mmol/L and 6.4 mmol/L respectively. Significant difference was found for attributes aroma, viscosity and overall acceptance of the two products. Our study found, BG22 from oats were has better physical attributes and is better accepted by the panelists. However, it is suggested that both products be taken together with milk or soy to improve the taste. The GI for BG25 was 79 (high GI) while BG22 was 32 (low GI). The BG22 with lower GI is significantly more satiating than BG25 and perhaps can be a choice of beverage for people who are managing diabetes and obesity.