Stabilized Avocado Pastes: Chemical Contents and Oxidative Changes During Storage

ABSTRACT

The nutritive compositions and oxidative stabilities of processed avocado pastes at ambient (30±1°C, RH80%) and refrigerator (5-6oC) storage temperatures were evaluated and studied. Avocado pulp was blended with ingredients, chilled, kneaded and shaped. For oxidative studies varying concentrations and combinations of Ascorbyl palmitate (AP) and Propyl gallate (PG) were blended with the pulp. Products were evaluated for their proximate composition, minerals and vitamin C contents. Stored products at ambient and refrigerated temperatures for 16 days, were evaluated for contents of free fatty acids (FFA), peroxide values (PV), thiobarbituric acid values (TBA), also changes in colour, odour and flavour/ aroma. The protein, carbohydrates and lipid contents of control (untreated) and stabilized pastes ranged from 2.7- 2.8%, 9.2 - 9.5% and 32.8-33.4%, respectively. The results of mineral analysis and their implications on human nutrition are discussed. Vitamin C contents ranged from 20.6-22.8mg/100g. Generally, stored products had lower FFA contents, PV and TBA values from days 0-4 and 0-8 at ambient and refrigerator temperatures, respectively. Highest percent FFA, PV and TBA values were obtained in the control samples while least values were recorded in products stabilized with AP+PG, 200/200ppm. The efficacy of the preservatives were of the order of AP+PG, 200/200ppm > AP+PG, 100/100ppm>AP, 200ppm>PG200ppm>untreated control. AP+PG, 200/200ppm significantly (P≥0.05) reduced % FFA, PV and TBA values in stored products and synergistically stabilized their colour, odour and flavour/aroma for 4 and 8 days at ambient and refrigerator storage temperatures, respectively.

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