Authors Mohamed. M. A.T. Morad , Ahmed Abou El-Yazied, Hany G. Abd El-Gawad, Hany S.Osman, Abou -Elwafa, S. M., Amr A. Metwally
Tomato (Solanum Lycopersicum Mill.) is considered one of the most grown horticultural crops having a short storage life due to its climacteric nature of ripening, susceptibility to postharvest microbial decay, mechanical damage, and high rate of losses during handling operations, tomato dipping in a solution of Aloe Vera Gel (10 % ( , Starch (2%) and Casein (2.5%) was the best treatment for reducing weight loss, decay, shriveling, also maintaining a general appearance, ascorbic acid, TSS, and increasing titratable acidity, total phenolic and the peroxidase activity compounds as compared with uncoated fruits. The tomato fruits dipping in Aloe Vera Gel (10%), and Starch (2%) were highly effective in preserving and maintaining the lycopene content and gave the lowest value of polyphenol oxidase activity at the end of storage time of tomato fruits at the end of storage time 28 days at 8 ± 1o”C and 95% RH, Tomato, Aloe Vera Gel, Starch, Citric Acid, Casein, Storability, TSS, Total Phenolic, Peroxidase Activity, Lycopene Content , and Polyphenol Oxidase Activity, tomato contents compounds as contents of lycopene, beta-carotene, magnesium, niacin, iron, phosphorus, potassium, riboflavin, sodium, and thiamine, postharvest period of tomato as a climacteric fruit is relatively short because many processes lead to a loss of quality and storability, including high respiration rates, transpiration, postharvest diseases, acceleration of the ripening process, and senescence, Fruit quality aspects include firmness, flavor, color, nutritional value, shelf life, and resistance to pathogens , Synthetic-plastic polymer, synthetic wax-based packaging or coatings, and chemical preservatives have been abundantly used for preserving fruits after harvest. However, these synthetic inputs are non-degradable and extremely risky to consumers and the environment, Edible coatings can protect fruits effectively from mechanical and microbial damage, prevent the migration of favorable volatiles, delay fruit senescence processes and provide an esthetic appearance, coatings meet the desire of consumers for safe and healthful foods since they are made of biodegradable and biocompatible materials, and in many circumstances, they may provide an alternative to synthetic packaging and antimicrobial ingredients, Aloe vera gel is considered one of the best edible films due to its hygroscopic properties, antimicrobial action, and biochemical attributes , aloe vera gel reduces the activity of cell-wall degradation enzymes and respiration rate, thus preventing the deterioration of harvested tomato fruits, also, Aloe vera gel could be considered a promising postharvest treatment to preserve fruit quality during cold storage, caseinates have been proposed as natural materials for edible coatings because proteins have some advantageous properties, such as their ability to form networks, plasticity, and elasticity, in addition to a good barrier to oxygen, carbon dioxide, and aromas, oxygen plays an important role in fruit degradation, as it is involved in many undesirable reactions including microorganisms growth, enzymatic browning, vitamin loss, and lipid oxidation, the use of caseinates might be considered a good alternative to get high protection to oxygen and retarding senescence while the storage period of fruits, Edible coatings of starch have similar physical properties to synthetic polymers, such as being transparent, odorless, tasteless, semipermeable to CO2, and resistant to the passage of O2, Starch-based coatings proven to extend the storage life of fruits, decrease weight loss, and maintain fruit quality during storage period, according to some studies, the effectiveness of starch as an edible coating should be mixed with antimicrobial compounds. One of the chemical compounds that could be used as an antimicrobial agent in edible coatings is citric acid. Citric acid is generally recognized as a safe chemical preservative that can act as an antimicrobial agent. The addition of citric acid in edible coatings inhibits the browning reaction and reduces losses because this acid acts as an antimicrobial agent, compared to other organic acids, citric acid is relatively cheap and easy to obtain.
