Zeitschrift für Lebensmittelverarbeitung und -technologie

Abstrakt

Characteristics of Okra under Different Process Pretreatments and Different Drying Conditions

Adesoji Matthew Olaniyan and Bamidele David Omoleyomi

Okra (Abelmoschus caillei) is a vegetable crop that is popular in the tropical region because of its easy cultivation, dependable yield, adaptability to varying weather conditions and resistance to diseases and pests. Apart from its high vitamin B and folic acid contents, okra is said to be very useful against genito-urinary disorders, spermatorrhoea and chronic dysentery while also used in curing ulcers and hemorrhoids. This vegetable crop is seasonal and highly perishable in its natural state after harvest resulting in huge postharvest losses during the production season and extreme scarcity in the off-season. According to past research, drying has demonstrated promising results in preventing postharvest losses and prolonging shelf lives of fruits and vegetables. This study was conducted to investigate the effects of osmotic dehydration process pretreatment and drying temperature on drying rate and quality attributes of okra. A 2 x 3 x 4 factorial experiment under a randomized complete block design was used for the experimental design and the drying process was carried out using a temperature-controlled dryer that has been designed and built prior to this study. Two levels of osmotic solution concentration (40 and 60°Brix of sucrose), three levels of osmotic process duration (60, 120 and 180 min) and four levels of drying temperature (50, 60, 70 and 80°C) were considered with each trial being carried out in triplicates. The quality attributes investigated included: ash content, crude fibre, crude fat, crude protein, bulk density, least gelation concentration and water absorption capacity. Results showed that drying rate, crude fibre, crude fat, crude protein, bulk density and least gelation concentration increased while ash content and water absorption capacity decreased with increase in drying temperature and osmotic solution concentration. However, drying rate and all the quality parameters increased with increase in drying temperature, osmotic solution concentration and osmotic process duration.