Sensory Evaluation of Gamma Irradiated Shrimp (Penaeus notialis) from Three Different Water Sources in Ghana

Shrimp is one of the world's most popular shellfish. It is cherished in Ghana due to a wide range of culinary applications such as its usage as food as well as food condiments in some local foods such as kenkey (local food prepared from fermented corn dough), pepper sauce (locally called shito), fast foods etc. The influence of gamma irradiation on the sensory and acceptability attributes of dried shrimp was evaluated. Sensory evaluation was carried out using steamed shrimp samples irradiated at doses 0 (control), 4, 8 and 10 kGy at a dose rate of 2.71 kGy/hr from a Cobalt 60 source (SLL 515, Hungary) batch irradiator and stored in polypropylene packs for 4 months at 28-30°C. Using a structured questionnaire, 30 male and female panelists independently assessed the samples for sensory attributes. Organoleptic scores were made according to a seven-point hedonic scale and a mean score of 4 used as the acceptable limit. Results of investigated parameters of colour, aroma, texture and taste recorded were of ranges of 1.04 ± 0.05 - 2.0 ± 0.05, 1.0 ± 0.04 - 2.16 ± 0.17, 1.08 ± 0.05 - 2.12 ± 0.17 and 1.64 ± 0.17 - 2.2 ± 0.17 respectively showed some statistical differences (p<0.05) among the treatments of samples. The overall the most accepted samples were shrimps from the sea and river sources pretreated with dose 10 kGy scored similarly. Sensory evaluation of the gamma irradiated shrimps showed acceptability for samples from non-irradiated shrimps with taste and texture influencing selection of preferred choice.