Influence of edible coatings on physico-chemical characteristics and shelf-life of papaya (Carica papaya) fruits during ambient storage

摘要

Papaya (Carica papaya L.) is one of the commercial fruit crops of tropical and sub-tropical region of the world. Papaya fruits have very high respiration and softening rates, making the storage and marketing of fruits challenging in domestic and international market. The fruits deteriorate rapidly after harvest. The main reasons of deterioration are weight loss, colour changes, softening, surface pitting, stem browning and loss of acidity and TSS. Among the different methods used to extend the shelf-life, application of edible coating have received attention world wide. In order to extend the shelf-life of papaya fruits at ambient storage, an experiment was conducted with the following edible coatings, T-1= carboxy methyl cellulose (CMC) (1% w/v), T-2= chitosan (1% w/v), T-3= Aloe vera gel, T-4= liquid paraffin wax 100%, T-5= sodium caseinate (1% w/v), T-6= kaolene (1% w/v), T-7= control (Water spray). Among all treatments, the highest effect on extending the shelf-life and delaying the ripening was recorded in paraffin wax coated fruits. Treatments were compared within 16 days where paraffin wax showed superiority in different cases attributing characters like physiological loss in weight (PLW) percentage (7.83%), fruit firmness (3.84), spoilage per cent (18.47%), total soluble solids (TSS) (9.58 %), ascorbic acid (63.36 mg/100 g), titratable acidity (0.147%), total sugars (8.35%), reducing sugar (5.30%), TSS: acid ratio (63.37), peel colour (3.68), taste (7.21) and appearance (5.73). The overall assessment of the present study concluded that paraffin wax was the most efficient edible coatings for extending the shelf-life and delaying the ripening of Red Lady papaya fruit.