Evaluation of Low Calorie Roselle Beverage

Abstract

Roselle calyces contained 10.85, 6.75, 8.61, 1.10, 13.60 and 69.94% of moisture crude protein, ash, ether extract, crude fiber and available carbohydrates, respectively. The major minerals of roselle calyces were Ca, Mg, P, Fe and K which contained 688.34, 234.68, 34.88, 33.42 and 20.56 mg/100g, respectively (on dry weight basis). Dried roselle calyces contained 113.60, 46.50, 28.68, 76.26 and 8.32 mg/100g from ascorbic acid, total polyphenols, flavonoids, tannins and anthocyanin, respectively (on dry weight basis). With respect to roselle beverage storage for 6 months indicated that T.S.S, ash, total sugars, reducing sugars, non-reducing sugars and titratable acidity ranged from 3.19 to 15.63, 3.33 to 7.25, 30.31 to 81.45, 12.60 to 20.81, 9.03 to 65.41 and 0.59 to 0.77%, respectively. It could be noticed that increasing storage period from 0 to 6 months was accompanied by significant decrease in total sugars, reducing sugars and titratable acidity of roselle beverage. pH value of roselle beverage ranged from 2.58 to 2.80. Total phenolic compounds, flavonoid components and the antioxidant activity ranged from 0.90 to 1.24, 0.34 to 0.83 mg/gm and 20.50 to 77.14 μmol/g, respectively. While, increasing storage period from 0 to 6 months led to significant decrease in total phenolic compounds, flavonoid components and the antioxidant activity. Also, organoleptic properties (color, odor, taste, appearance and overall acceptability) were decreased significantly during storage period of roselle beverage.