Storage Stability and Sensory Properties of Raha Sweet Colored with Crude and Purified Red Grape Anthocyanins and Synthetic Food Colorant

Abstract

Anthocyanins (ANCs) are water-soluble pigments that are useful as nutraceuticals due to their health benefits. This study was performed to evaluate the storage stability of purified and crude red grape ANCs in Raha Sweet (RS) during storage and to evaluate its sensory properties. ANCs were extracted from red grape pomace and purified with a macroporous resin. RS was prepared and colored with a synthetic food dye, Carmoisine (control), and ANCs (crude and purified). Pigments were extracted from RS weekly for a period of seven weeks and the absorbance was read spectrophotometrically. RS colored with ANCs was evaluated for its color and other sensory properties against another RS colored with the control. Results showed that the degradation of ANCs in RS followed the first-order reaction model, unlike the control, which showed no degradation during storage. The half-life of crude ANCs was three times higher than that of the purified ones, and RS colored with ANCs received a significantly (p < 0.05) lower score for color than that of RS colored with the control. ANCs could provide the food industry with a natural alternative to synthetic dyes to color foods with high sugar content that are stored for a short period of time.

Keywords

• anthocyanins
• grapes
• Raha Sweet
• pigments
• half-life
• storage stability