EFFECT OF SODIUM HYPOCHLORITE AND ALOE GEL ON SHELF LIFE AND QUALITY OF TOMATO (Solanum lycopersicum L.) FRUITS

Abstract

Due to their climacteric nature, high water content, active metabolic activities, and microbial spoilage, tomato fruits are very susceptible to post-harvest deterioration which is the major problem of its production in Ethiopia. Edible coatings and chlorination are used to extend storage life and reduce quality deterioration by altering gas permeability, delaying ripening, reducing water loss and microbial decay of the fruits. The study was therefore aimed to assess the effect of NaOCl dipping and Aloe Gel (AG) coating on the post-harvest quality and storage life of tomato fruits.Uniform and healthy fruits of the Shanty PM tomato variety were harvested at the turning stage. The experiment was arranged in a factorial combinationby using a completely randomized design with three replications. The treatments comprised of four levels of NaOCl (0 ppm, 100 ppm, 200 ppm, and 300 ppm) and five levels of AG (0%, 25%, 50%, 75%, and 100%). The treated fruits were stored at ambient conditions (17.5- 24.85oC T o and 74.04%RH) for assessment of physicochemical qualities, which was done at 4- day intervals. The study results revealed that samples treated with 300ppm NaOCl + 100% AG and 200ppm NaOCl + 100% AG verified to be the most effective in lowering physiological loss in fruit weight (17.16% and 17.39%), decay percentage (44.19% and 44.52%), higher marketability (55.68% and 55.35%), firmness(1.25 and 1.12 Nmm-1 ), and shelf life (29 days). The use of the same treatment has also significantly slowed down the decrease in acidity (0.33% and 0.34%) and rise in ascorbic acid content(15.10mg100 g-1 and 15.05mg100 g-1 ) toward the end of the storage period.Moreover, all of the quality attributes of tomato fruits were significantly preserved with an application of 100% AG aloneas compared to its lower levels. In conclusion, the combination treatment of NaOCl and AG treatments, particularly treatment with 300ppm NaOCl + 100% AG or 200ppm NaOCl + 100% AG, could potentially be used to extend the shelf life of tomatoes while maintaining most of their quality attributes. However, further research is suggested with consideration of more tomato varieties, harvesting stages, different types of edible coatings, and chlorine forms to give conclusive recommendations for tomato postharvest treatment.