Edible Composite Coating of Methyl Cellulose for Post-Harvest Extension of Shelf-Life of Finger Hot Indian Pepper (Pusa jwala)

Abstract

Chillies of Pusa jwala variety were coated with composite coating formulation made up of methyl cellulose (MC) and oleic acid (OA) to evaluate the effectiveness of edible coating in extending the shelf-life of chillies. Edible coating showed good stability, transparency and glossiness when applied on chilli fruit. The coatings when applied on green chillies resulted in restriction in metabolic activities and delayed senescence. MC-based coating was found to reduce physiological weight loss, textural softening and development of red pigment in the fruit peel. Coated fruit synthesized phenolic compound slower than uncoated fruit bringing about slow changes in capsaicin content as well. MC-OA based coating could extend the shelf-life of green chillies to 8 days under ambient storage conditions (24 ± 1C, RH 70 ± 5%) against the 5-day shelf-life of uncoated ones. Practical Applications Chilli is considered as one of the most important commercial spice crops and is a widely used universal spice. Preserving fresh chillies with simple, edible coating formulation would reduce the cost of preservation using other expensive and energy consuming techniques such as cold storage and CAP/MAP. As the coating gives each fruit its own micro-packaging, coated fruits can be well handled as those of uncoated chillies. Being edible and water soluble the coating would not be harmful to consumers compared to use of chemical preservatives.