PHYSICOCHEMICAL RESPONSE OF APPLE PULP TO CHEMICAL PRESERVATIVES AND ANTIOXIDANT DURING STORAGE

Abstract

ABSTRACT: A research was carried out to investigate the effect of chemical preservatives and antioxidants mixed in different concentrations on the overall quality of apple pulp packed in plastic containers, stored at ambient temperature (25-35C) for 90 days. The treatments were To (apple pulp) + T1 (apple pulp + 0.1 % sodium benzoate + 0.1 % citric acid) + T2 (apple pulp + 0.1 % sodium benzoate + 0.5 % citric acid) + T3 (apple pulp + 0.1% potassium metabisulphite + 0.1 % citric acid) + T4 (apple pulp + 0.1 % potassium metabisulphite + 0.5 % citric acid) T5 (apple pulp + 0.5 % potassium metabisulphite+0.5% sodium benzoate + 0.1 % citric acid) T6 (apple pulp + 0.5 % potassium metabisulphite+0.5% sodium benzoate + 0.5 % citric acid). The samples were studied for ascorbic acid, % acidity, pH, total soluble solids (TSS), sugar acid ratio, minerals contents (Ca, Mg, Iron, Potassium and sodium) and for organoleptic evaluation (color, flavor and overall acceptability). A decrease was recorded in ascorbic acid content (25.98 to 21.45 mg/100g), sugar acid ratio (14.20 to 13.92), pH (3.62 to 3.28), calcium (12.12 to 4.74 mg/100g), magnesium (12.64 to 11.02), iron (31.22 to 15.65 mg/100g) and sodium (0.57 to 0.45 mg/100 g while an increase was recorded in titratable acidity (0.31 to 0.40), TSS (9.71 brix to 11.36 brix) and potassium (140.00 to 176.22 mg/100g). During organoleptic evaluation samples T3 and T4 were found most acceptable during storage. Statistical analysis showed that storage intervals and treatments had a significant (P<0.05) effect on physico-chemical and sensory analysis of apple pulp.