اثر پوشش های خوراکی فعال بر پایه متیل سلولز بر ماندگاری گوجه فرنگی

Edible films and coatings are used to protect food products and improve their quality and shelf life. The objective of this study was to evaluate the effect of two methyl cellulose- based active coatings on the quality and storage life of tomato. Fruits were dipped in to active methyl cellulose (MC) coating (MC, glycerol and potassium sorbate) or active MC-palmitic acid coating (MC, glycerol, potassium sorbate and palmitic acid) for 1min at 20^oC, then air-dried at room temperature and stored with uncoated samples at 15 ^oC and 80-85% RH for 21 days. At one day intervals, coated and uncoated fruits were removed and evaluated for weight loss, total soluble solids, titrable acidity, pH, skin color, firmness, failure energy, ascorbic acid content, yeasts and moulds count and overall acceptability. It was revealed that the coated fruits showed lower weight loss (up to 2.5 times), ripening rate, spoilage incidence (2-3 times) while, the skin color, ascorbic acid content, sensory quality and overall acceptability were higher in coated tomatoes when compared with control during storage time. However, non significant differences in the properties of tomato were observed by adding palmitic acid to the formulation of MC active coating.