Evaluation of Gamma Irradiation Effects on Brazilian Orange Melon (Cucumis melo L.)

The contents of each section may be provided to understand easily about the paper. The melon (Cucumis melo L. var. inodorus) is one of the oldest crops worldwide. There are many species which differs in fruit size, morphology and organoleptic properties [1]. In Brazil, the melon with a planted area of 12,500 hectares is one of the most cultivated Cucurbitaceae. Currently, the two largest producers are the poles Mossoró-Assu (RN) and Lower Jaguaribe (CE). Among the main types of melons produced in the region, highlight the "honeydew”, the “gália”, the “cantaloupe”, the “charentais”, the “yellow” and the “orange flesh”. On current data, Brazil exported about 152 million dollars in melon, this fruit is considered the second most consumed fruit "in natura" and that contributed most to the brazilian trade balance [1]. 

The orange flesh melon, presents an excellent acceptance in domestic and foreign markets, especially due to their high level of soluble solids. Moreover, the β-carotene is its main component and an antioxidant carotenoid pigment. In nature, is a source of vitamin A to obtain through metabolism in the human body. The carotenoid compounds presents a β-ionone in its structure and a side chain with at least two isoprenol units and belong to a large group of compounds collectively known as terpenes and terpenoids. Great discoveries have been made about β-carotene properties. Today we know that it is an antioxidant that benefits the night vision, boosts immunity, gives elasticity to the skin, increases the brightness of the hair and strengthen nails, besides acting in fat metabolism [2,3]. 

A deficiency of vitamin A was detected in several Brazilian states like Amazonas, Rio Grande do Norte, Paraíba, Pernambuco, Bahia, Minas Gerais, São Paulo and Santa Catarina, and may be recognized as a public health problem [4].

 A positive correlation between the consumption of nutritious foods and protection against the development of chronic diseases has been observed. According to the Dietary Reference Intakes (DRI), the Recommended Daily Amount (RDA) of vitamin A for healthy adults is: 900 μg RAE for men and 700 μg RAE for women. Retinol Activity Equivalent (RAE) is used to describe vitamin A activities of carotenoids, 1 μg of RAE is equivalent to vitamin A activity of 12μg of β-carotene in mixed food [3,4,5].

 Nowadays, worldwide there is an imbalance between population and food supply, and the problem of food availability has been worsening over the past 20 years. The reduction of post harvest losses that occur annually in different stages of obtaining food from production to consumption is a measure to change the growth pattern of this imbalance. Studies estimate those losses of vegetables occurring in more than 30% at the stages of handling, transport, storage and marketing.3 In this context the use of food irradiation is very promising and very important, through their contribution to conservation, reducing  post harvest losses and the possibility of improving the food supply. The process involves exposing food as packaged or in bulk, to a highly penetrating radiation field, for a given time, in order to destroy pathogenic bacteria, parasites, fungi and insects, or inhibit the ripening process of fruits [6,7]. 

According a joint FAO/IAEA/WHO study group on high-dose irradiation reviewed determining to the toxicological, nutritional, radiation chemical and physical aspects of food irradiated to doses above 10 kGy and concluded that foods treated with doses greater that 10 kGy can be considered safe and nutritionally adequate, when it were produced under established good manufacturing practice (GMP). This study evaluated the gamma irradiation effects in brazilian orange melon by analysis of soluble solids, titratable acidity, pH, total carotenoids, β-carotene, sugar, volatiles compounds and sensory analysis [8].