Effects of smoking and sun-drying on proximate, fatty and amino acids compositions of Southern pink shrimp (Penaeus notialis)

Abstract

Traditional techniques of smoking and sun drying were investigated to understand their effects on nutritional qualities of Southern pink shrimp against present human dietary needs. Shrimps subjected to hot smoking at 71 °C and sun drying at ambient temperature of 31 °C treatments were compared to fresh samples. Proximate composition dry weight basis showed that smoked product were highest in protein and carbohydrate (P < 0.05) while fat was raised in sundried products (P < 0.05). The monounsaturated fatty acid (MUFAs) were highest ranging from 35.87 to 40.35 % in all products. Oleic acid (18:1) had highest value of 24.26 % in the smoked. Eicosapentanoic acid (C20:5 n-3) was highest in the sundried while Docosahexaenoic acid (C22:6 n-3) predominated in the fresh. The shrimp protein had Glutamate as the most abundant amino acid in the three forms. Both preservation methods significantly (P < 0.01) raised the values of tyrosine, histidine and leucine. The Ω-3/Ω-6 ratios showed that prawn is rich in omega 3. The highest arginine/lysine ratio (1.54) was obtained in sundried. The EAA/NEAA ratios ranged from 0.72 to 0.80 while index of atherogenicity (IA) and index of thrombogenicity (IT) ranged from 0.71 to 0.82 and 0.21 to 0.30 respectively in all forms. All products forms showed different advantages with respect to quality and nutrition, smoked samples however, offered the best benefits. Information provided is the first detailed study on the impacts of smoking and sun-drying on the nutritional qualities of a shrimp with tremendous economic and nutritional importance.

Small-scale fisheries in the context of traditional post-harvest practice and the quest for food and nutritional security in Nigeria

“…Appropriate nutrition includes feeding children with a variety of foods to ensure that nutrient requirements are met. It is well known that plant-based complementary foods (food given to a child after exclusive breastfeeding) by themselves are insufficient to meet the needs for certain micronutrients [1,2]. It has been advised that meat, poultry, fish, or eggs should be eaten daily, or as often as possible.…”

“…It has been advised that meat, poultry, fish, or eggs should be eaten daily, or as often as possible. Fish has been variously suggested to be an important part of infant feed or complementary food [1,2].…”

“…Smoked products offered the healthiest advantage with the lowest values of saturated fatty acids, index of atherogenicity, index of thrombogenicity, and the highest omega-3/-6 ratios, which are important for reducing coronary heart disease (CHD) in food consumption [1]. Furthermore, smoking increases the concentration of alanine, threonine, tyrosine, and cysteine and accounts for a sweeter taste of the shrimp over other product forms, while sun-dried specimens were found to have increased levels of histidine and arginine [1,2].…”

“…However, this technique makes the fish susceptible to predations by animals. This method is commonly used in the Northern parts of the country, due to the sun's intensity and other favourable conditions such as dry weather, low humidity, and clear skies [2]. Fish is typically sun-dried for three to ten days, but drying periods of one to three days are more common [36].…”

“…In Nigeria, the burden of supplying local fish needs to ensure food security and nutrition is borne mostly by small-scale fishers (Table 1). Table 1 once outside water because of its chemical composition, which may be made up of 70-84% water, 15-24% protein, 0.1-22% fat, and 1-2% minerals [1,2]. Depending on the fish type, factors including high moisture and fat and protein contents promote rapid changes in quality in fish.…”