Effect of wax coating and cold storage on quality retention of clemenules mandarin

Abstract:

Post-harvest losses in Clemenules mandarin across the Spanish Mediterranean citrus belt run at 28-36% and eat away a sizeable share of grower income year after year. This research tested the combined effect of food-grade carnauba wax coating (at 0, 3, 6, 9 and 12% concentrations) and cold storage (4 ± 1 °C, 85-90% RH) on the quality retention of Clemenules fruits over a 60-day storage window. Freshly harvested fruits (80-85% maturity) were sourced from the Sagunto cluster, surface-sterilised, dipped in wax emulsion for 2 minutes, surface-dried and placed in CFB boxes. Physiological loss in weight, firmness, juice content, TSS, acidity, ascorbic acid, and spoilage percentage were recorded at 15-day intervals. The 9% wax treatment gave the best overall performance: PLW stayed at 7.8% against 19.3% in control, firmness retention at 68% against 21%, ascorbic acid retention at 74.3% against 41.8%, and spoilage at 8.6% against 31.2% by day 60. At 12% concentration, a slight sticky surface and off-flavour crept in, indicating an upper limit for safe use. Wax coating at 9% combined with cold storage pushed the effective market life of Clemenules from 18-22 days to 52-56 days without compromising sensory acceptability.