Physico-chemical, Sensorial and Microbiological Quality of Frozen Avocado (Persea americana Mill.) Slices

Abstract

Background: Avocado (Persea americana Mill), is a subtropical, evergreen fruit tree belonging to the family Lauraceae. Due to the unique climacteric nature of the fruit, avocado starts ripening immediately after harvest and have poor post harvest life. Since thermal processing has adverse effects on the fruit quality, avocado processing is challenging. Methods: Avocado fruit slices were subjected to quick freezing (-20oC within 30 minutes) after pre-treatment with sucrose (20-40%), ascorbic acid (0.5%) along with one of the antimicrobial compounds like potassium metabisulphite, sodium benzoate or potassium sorbate (0.1%) and subsequently packed in 200 gauge LDPE pouches stored at -18oC. Result: Avocado slices treated with 40% sucrose, 0.5% ascorbic acid along with 0.1% potassium metabisulphite (T7) recorded with higher ascorbic acid (92 mg/100 g) after one month and total protein (1.43 g/100 g) content after three months of storage and desirably lowest values in polyphenol oxidase activity throughout the storage, peroxide value (15.56 mEq/kg) and water activity (0.956) after one month of storage was observed as the best method of preservation.