Quality Characteristics of Cashew Apple Juice as Affected by Pre-Treatment Techniques

Cashew apples deteriorate easily when kept for a few hours after plucking. The astringency of cashew apples has also limited its utilization and overall acceptability. This study, therefore, evaluated the effect of pretreatments on the quality of cashew juice. Fresh cashew apples were cleaned and pre-treated by blanching at 50 °C, 60 °C, 70 °C and 80 °C for 20 minutes and another batch of cashew apples was dipped in a brine of 5% concentration (w/v) at 80 °C for 20 minutes. Then, cashew juice was extracted from pre-treated apples and subjected to physicochemical, vitamins, minerals, anti-nutrient, and sensory analysis. The cashew apple blanched at 70 °C had the highest total solid, pH, and brix with the values 14.16%, 4.27, and 11.30 respectively. All these values differed significantly from the untreated samples except the brix. Samples blanched at 80 °C had the highest vitamins A and B₁ (0.192 and 0.26 mg/100 g) and cashew apples blanched at 50 °C had the highest vitamins B₂, B₃, and C (0.68, 0.29, and 69.00 mg/100 g) which differed significantly from the untreated sample. The potassium, calcium, iron, and zinc ranged from 137.27 to 312.14 mg/100 g, 235.78 to 510.32 mg/100 g, 17.86 to 40.77 mg/100 g, and 0.22 to 0.55 mg/100 g, respectively. All treated samples had significantly higher mineral composition than the untreated cashew apple juice. The anti-nutritional factor ranged from 1.12 to 1.39 mg/100 g for total phenol, 0.12 to 0.28 mg/100 g for flavonoid, and 0.67 to 0.83 mg/100 g for tannin. Both treated and untreated cashew apple juice had no coliform. The result of the sensory evaluation showed that brine-treated juice had a higher acceptability value than other samples. Hence, pre-treatments of cashew apples enhanced the mineral and vitamin contents of the juice and increased the general acceptability.