Effect of surface coatings on postharvest quality of Kinnow mandarin

The study was conducted to observe the effect of surface coatings such as lac based wax, Citrashine^®, P-104^® and Niprofresh^TM on Kinnow mandarin with the objective to extend its shelf-life. For this, Kinnow fruit were treated with different surface coatings and stored at 5º ± 1ºC temperature and 85–90% RH. Our results indicated that all surface coatings maintained a very good profile of quality parameters, but the surface coating of lac based wax was the best followed by Citrashine^®, P-104^® and Niprofresh^TM. All surface coatings influenced all the studied attributes significantly but lac based wax was the most effective in maintaining lowest physiological loss in weight (9.7%), fruit firmness (6.5 N), respiration rate (1.3 ml CO₂ kg⁻¹ h⁻¹), and ethylene evolution rate (1.5 μl kg⁻¹ h⁻¹). Similarly, all the surface coatings used could retain quality attributes (souble solids content, titratable acidity and ascorbic acid content) of the fruits without any adverse effect. Results suggested that surface coatings have potential to enhance shelf-life of Kinnow mandarin as its fruits could be successfully stored for 60 days under cold storage conditions with highly acceptable sensory quality. The non-coated fruits, on the other hand, maintained postharvest shelf-life of 45 days in cold storage. The surface coatings of indigenous origin (lac-based wax & P-104) can also recommended owning to their cheaper cost and reasonable effect on storage life.