Effect of clarification on physicochemical properties and nutrient retention of pressed and blended cashew apple juice

Abstract

The cashew apple is a nutritious pseudofruit of the cashew tree, after the nut. It is highly perishable and has an astringent taste, which hinder its utilization in the food sector. This study was designed to optimize clarification of cashew apple juice (CAJ) using gelatine, and assess the effect of clarification on physicochemical properties (titratable acidity, total soluble solids, and pH), nutrient retention, and sensory quality of pressed and blended CAJ. CAJ was treated with gelatine concentrations (0, 0.025, 0.05, 0.1, 0.2, 0.3, and 0.4 g/L) at room temperature (24–26°C) for 1, 2, 4, 6, 8, 10, and 12 h. Both clarified and unclarified juice were analyzed for tannin, total phenol, β-carotene, vitamin C, sugar, minerals, antioxidant activity, and physicochemical and sensory qualities. The results showed that tannin in pressed CAJ was optimally reduced from 217.6 mg/100 ml TAE to 24.6 mg/100 ml TAE, and from 258.0 mg/100 ml TAE to 55.0 mg/100 ml TAE in blended CAJ, using 0.2 g of gelatine in a liter of juice, for 2 h at room temperature. Both CAJ with and without clarification showed no significant difference in pH, total soluble solids, and titratable acidity (p < .05). However, blended CAJ had higher contents of total phenol, tannin, β-carotene, vitamin C, sugar, minerals, and antioxidant activity (p < .05). The use of a low concentration (0.2 g/L) of gelatine in a liter of either blended or pressed CAJ yielded sweet and less astringent CAJ with high-intensity yellow color. The technologies performed well at room temperature and therefore provide the basis for potential business investment.