Effect of Different Drying Methods on Selected Quality Attributes of Okra (Abelmoschus esculentus L.)

Abstract

This study examined the impact of different drying techniques and packaging materials on specific quality characteristics of dehydrated okra. The techniques employed for drying and packaging, along with the specific types of dried okra used, should be explicitly described in the Materials and Methods section. The okra samples underwent pre-treatment by immersing them in hot water and salt water prior to being dried using two different ways, namely a laboratory oven and a microwave. The untreated samples were utilised as the control. The desiccated specimens were enclosed in Low Density Polyethylene (LDPE) and High Density Polyethylene (HDPE) pouches and kept in normal environmental conditions for a duration of eight weeks. The quality parameters of pH, colour, and viscosity were tested at two-week intervals for the entire storage duration. The initial pH of the fresh sample was 6.560±0.087. After blanching with fresh water and salt water, the pH climbed to 6.77±0.037 and 6.78±0.041, respectively. The pH further increased when the sample was dried in an oven, reaching 7.03±0.057 and 6.91±0.037. However, the pH declined when the sample was dried in a microwave, resulting in pH values of 6.18±0.051 and 6.39±0.033. The initial colour difference of the fresh sample (45.360±1.197) increased following the process of blanching in fresh water (45.900±1.527) and salt water (47.867±1.221), and subsequently dropped considerably after undergoing oven drying (9.950±1.221, 10.610±1.987) and microwave drying (8.590±1.294, 4.900±0.945). The viscosity of the fresh sample increased from 0.0124±0.003 to 0.0144±0.003 after blanching in boiled fresh water. However, it reduced to 0.008±0.002 after salt water blanching. After oven drying, the viscosity climbed to 0.016±0.001 and 0.0736±0.0257. Similarly, after microwave drying, the viscosity increased to 0.0928±0.0037 and 0.0256±0.007. Both LDPE and HDPE films were deemed suitable for packaging the dried okra samples, as they exhibited minimal contact with the surrounding environment and effectively maintained the quality of the product during the eight-week storage period.