Fish drying using different drying methods at different temperatures for fish Tilapia nilotica (Oreochromis niloticus)

Аннотация

This study was conducted at the Institute of Agricultural Engineering and Food Processing, Georg-August University, Gottening- Germany during the year 2016. The objectives of the study were to investigate the effect of drying method using three levels of drying temperatures on drying rate and drying time of fish Tilapia nilotica (Oreochromis niloticus). These methods are hot air (oven) drying; Microwave drying and infrared drying. The levels of temperatures were 40, 50 and 60˚C for each of the drying method. The results show that, there is direct relationship between drying temperature and drying rate and inverse relationship between temperature and drying time i.e. as the temperature of the drying increases the drying rate will increase and the drying time will decrease and vice versa. For oven drying method the lowest drying time was obtained at temperature of 60 °C (7 hours) and the highest drying time was encountered at temperature 40 °C (17 hours). Also the highest drying rate (37.232g water∕100 g of DM ∕hour) was found at temperature of 60 °C and the lowest drying rate (14.936 g water∕100 g of DM ∕hour) was obtained at temperature of 40 °C. When using Microwave drying method the lowest drying time was obtained at temperature of 60 °C (5 hours) and the highest drying time was obtained at temperature 40 °C (22 hours) and the highest drying rate (52.208 g water∕100 g of DM ∕hour) was obtained at temperature of 60 °C and the lowest drying rate (11.032 g water∕100 g of DM ∕hour was obtained at temperature of 40 °C. In case of infrared drying method the low drying time was obtained at temperature of 60 °C (8 hours)
and the highest drying time was found at temperature 40 °C (14 hours) and the highest drying rate (39.589 g water∕100 g of DM ∕hour) was obtained at temperature of 60 °C and the lowest drying rate (18.009 g water∕100 g of DM ∕hour) was obtained at temperature of 40 °C. Statistical analysis using Eviews program show that microwave gives better results.