Acceptability, nutritional, and potential health values of sweet sorghum [Sorghum bicolor (L.) Moench] coffee substitute

Abstract

Utilization of sorghum to improve nutrition and health among Filipinos is limited due to insufficient information from research on the crop as a source of valuable nutrients and health promoting phytochemicals. The objective of this study was to develop an acceptable, nutritious, and healthful coffee substitute from sweet sorghum grains. The sweet sorghum coffee substitute (SSCS) was made by combining different roasting time of the grains (50, 60, and 70 min) at 226±5 o C, powder to water ratio (16 g/250 mL -1 , 24 g/250 mL -1 ), and brewing time (3 and 6 min). The 12 SSCS brewed samples were subjected to sensory evaluation composed of 55 untrained coffee drinker panelist. The most acceptable SSCS and the raw sorghum grain were analyzed for proximate composition, starch, amylose, dietary fiber, fatty acid profile, phytochemicals (total phenols, flavonoids, tannins) and antioxidant activity. The results showed that roasting time of the grains had a significant effect on the sensory characteristics and acceptability of the SSCS brew while powder to water ratio and brewing time have no effect. Roasting sweet sorghum grains for 70 min at 226±5 o C and brewing using the powder to water ratio of 16 g/ 250 mL -1 for 3 min produced the most acceptable sample with characteristic dark brown color, aroma and flavor resembling rice coffee, and coffee-like bitterness. This study also revealed that SSCS could be a potential health and nutritious beverage as its powder provides energy from carbohydrates and protein, is low in fat particularly saturated fat, contains essential fatty acids, and has dietary fiber. Moreover, SSCS powder contains phytochemicals, such as phenols particularly flavonoids, which contribute to its high antioxidant activity. These findings suggest that, in general, SSCS could be a beneficial in preventing diseases involving oxidative stress and chronic diseases.