Efeito da adição de pimenta biquinho (Capsicum chinense) como antioxidante natural em conservas de sardinhas (Sardina pilchardus Walbaum, 1792)

Abstract

Fish muscle contains proteins of high biological value, highly digestible, in addition cholesterol and polyunsaturated fatty acids (PUFAs), especially the fatty acids of the ω-3 family, which have beneficial effects on health. The sardine (Sardina pilchardus) is a fish widely consumed in canned fish and in the manufacture of which cover liquids (CL) are used, which favor the dissipation of heat by the can. However, the heat treatment used during canning causes the oxidation of PUFAs and cholesterol present in sardines and, as a consequence, there is the production of undesirable compounds for human consumption, mainly from the oxidation of cholesterol (COPs). The use of herbs, spices and fruits with antioxidant properties in food matrices is described as mitigating the harmful effects of heat. Biquinho pepper (Capsicum chinense) has low pungency and its fruits have bioactive compounds with antioxidant actions. In this way, the present research aims to verify the effects of adding the fruits of the biquinho pepper in canned sardines with soy oil as CL. Concentrations of 0, 2, 4, 6 and 8% of biquinho pepper were used in relation to the net weight of the can, in order to evaluate their protective effect against lipid oxidation. Biquinho pepper (BP) was characterized and the presence of bioactive compounds such as flavonoids, carotenoids, anthocyanins and total phenolics was verified. In addition, significant antioxidant potential was found through assays (FRAP and DPPH). An increase in the MUFAs of the sardines was observed at the addition level of 6% (28.53 ± 0.61 g /100 g oil) in relation to the control samples (27.25 ± 0.43 g /100 g oil). As for PUFAs contents, the control samples obtained the lowest results (27.46 ± 0.11 g/100 g oil) when compared to the different levels of BP addition, which did not present significant differences. These results are related to the protective effects of BP as well as the absorption of CL, since elevations (2, 6 and 8%) were observed in the levels of linoleic acid, which is commonly reported as a typical fatty acid of this vegetable oil, when compared with data from control sardine samples. The heat treatment promoted a reduction in cholesterol levels in control samples of sardines, with consequent production of COPs and their exchange for CL. For samples of sardines added with BP, regardless of the level of addition, there was a protective effect against the degradation of cholesterol and consequent formation of COPs. Regarding the CL, a high concentration (p ≤ 0.05) of COPs was observed in the control samples (264.86 ± 6.33 μg / g) in relation to the different levels of BP addition, which may be related to the absence of BP in these samples, in which there was greater cholesterol degradation and production of COPs. The greatest protective effect on CL occurred with the addition of 6% BP (60.88 ± 6.00 μg / g). In the color analysis of the sardines, the 2% BP samples were the ones that differed the least from the control samples, while the 8% BP samples showed the greatest changes, due to the greater addition of BP. For CL, it was verified through Pearson's correlation that their color parameters were inversely affected with the presence of COPs. Biquinho pepper in puree form was able to attenuate the deleterious effects of lipid oxidation in canned sardines.