Efeito da defumação sobre o valor nutricional do camarão sete-barbas (Xiphopenaeus kroyeri, Heller, 1862)

Abstract

Crustaceans are distinguished for their great commercial interest and good acceptance in the marketplace. However, they present easy deterioration, mainly due to their pH close to the neutral point, high water activity and composition in terms of unsaturated lipids to suffer oxidation. Therefore, the process of smoking extends the life and adds value to the product. However, this process may cause changes in the nutritional properties of food, making it more susceptible to lipid oxidation with consequent formation of cholesterol oxides, which are biologically active compounds, considered cytotoxic, mutagenic, carcinogenic and atherogenic. Considering the dearth of information about the chemical composition of the seven-beards shrimp (Xiphopenaeus kroyeri) smoked in the Pontal do Peba Alagoas (Brazil), during this work we studied the influence of smoking for its nutritional value. Then, the proximate composition, calorific value, pH, chlorides concentration and profile of fatty acids, cholesterol and cholesterol oxides were determined in the natura and smoked forms of this food. For the natura and smoked seven-beards shrimp, we obtained the following results, respectively: on a dry basis lipids: 6.85% and 5.18%; protein: 88.93% and 72.36%; ash: 8.00% and 23.58%; calories: 424.37 Kcal/100 g and 341.46 Kcal/100 g; chlorides: 3.61% and 17.86%; and on a wet basis - moisture: 77.87% and 40.32%; pH: 7.30 and 7.37; fatty acids: saturated: 39.78% and 52.35%; polyunsaturated: 39.58% and 28.30%; omega-3: 26.61% and 19.22%; omega-6: 8.79% and 6.30%; cholesterol: 145.08 mg/100 g and 297.59 mg/100 g; cholesterol oxides (dry basis): 7-keto: 8.47 µg/g and 8.56 µg/g; 7-alpha: 8.40 µg/g and 5.14 µg/g; 7-beta: 2.83 µg/g and 1.39 µg/g. It was concluded that seven-beards shrimp has a high nutritional value and it is a good source of essential fatty acids, but its smoked form leads to significant changes in their chemical composition, especially in their lipid profile, with no significant influence on the formation of cholesterol oxides.