STORABILITY POTENTIALS OF SELECTED FRUITS BY EVAPORATIVE COOLING USING DIFFERENT LOCALLY SOURCED

Abstract

Fruits are generally prone to spoilage based on their biological origin. The wastage arising from fruit decay is enormous, limiting the quantity available for consumption, reducing the economic viability and also constituting a treat to human health arising from vitamin deficiency and insufficient antibodies in the human bodies. Hence, the need for application of different pads to increase the shelf life of fruits to meet with the food requirement of the society. Three different pads (Jute fibre, Stem sponge fibre and Sponge gourd fibre) were used for ECSs as lagging materials. The pad materials have different physical properties in terms of length, breath, mean diameter, thickness, bulk mass, density and volume. The samples in ECSs were tested over a period of 14days and compared with the control and refrigerating cooling systems. The Nutritional constituents of the pad materials showed that crude fibre of the pad materials was found to be more than one third with major constituents being lignin, hemicellulose and cellulose but with different composition, which makes the fibres to behave differently in the cooling structure. The research results indicate that there was increase in the rate of water absorption of the pads with temperature for all the cooling pads as compared to room temperature. Moreover, the increase in the quantity of water absorbed by the pads increases linearly with the soaking time. The average atmospheric pressure and air velocity of the study area is 850.1134mmHg 0.08m/s and 0.105m/s respectively. The mean temperature and relative humidity of the cooling medium were 23.470C & 84.13%, 22.700C & 84.13%, 23.640C & 83.97% and 16.930C & 84.10% for the sponge gourd, Jute, Stem Control sponge and refrigeration respectively. The highest cooling capacity was found in the Jute fibre evaporative cooling(crop) system with a mean value of 34.63W. The result of a lower mean temperature (22.70C) with experienced in Jute fibre, with lowest water absorption rate of 0.033ml/min for produce under preservation with minimal weight loss as compared to other cooling medium other than the refrigerator which implies that Jute fibre pad was the superior cooling pad. The physical appearance of the produce in Jute fibre and stem sponge fibre shows better storability as compared to other ECSs. All the chemical compositions analyzed of samples in the ECSs were within the standard acceptable range when compared with standard specification of Standard Organization of Nigeria and international commission on microbiology specification for foods. Based on chemical and microbial evaluation of sweet orange and egg-plant stored in the ECSs Jute (Corchorus capsularis) had proved to be the best in increasing the shelf life of the fruits. The storability potential of the stored fruits (sweet orange and egg-plant) were directly proportional to the change content in the vitamin C contents of the stored fruits in the structures.