Effect of Concentration of Flaxseed (Linum usitatissimum) and Duration of Administration on Fatty Acid Profile, and Oxidative Stability of Pork Meat

SIMPLE SUMMARY: Dietary fat intake is substantially high in Western countries, resulting in overweight, obesity and cardiovascular diseases (CVD) among consumers. One way to reduce the incidence of CVD is to change food consumption and food intake with a higher content of polyunsaturated fatty acids (PUFA) in the human diet. Meat and meat products are considered to be the main source of dietary fats, especially as a source of saturated fatty acids. The aim of this study was to increase the proportion of PUFAs and, conversely, to decrease the proportion of saturated fatty acids in fat of pork meat. Flaxseed with a concentration of alpha-linolenic acid (ALA) at 57% was used in the swine diet. Flaxseed supplementation at two inclusion levels (5% and 10%) in two time intervals (3 and 6 weeks before slaughter) was evaluated. The aim was to increase the proportion of n-3 PUFAs, especially ALA, eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) and to improve the n-6/n-3 PUFA ratio in produced pork meat. The storage conditions and oxidation stability of the produced meat under refrigerator temperature (+4 °C) were also observed. ABSTRACT: Flaxseed is a common ingredient used for livestock feed. The aim of this work was to study the effect of a diet supplemented with flaxseed at 5% and 10% concentrations in the intervals of 3 and 6 weeks prior slaughter on fatty acid profile and oxidative stability of pork meat. Meat samples were collected after slaughter from each animal (five groups, n = 6). Samples of the musculus longissimus dorsi (MLD) and the musculus gluteobiceps (MGB) were selected. Chemical composition, fatty acid profile and oxidative stability during the storage of meat under chilling conditions (4 °C, 7 days) was analyzed. The addition of flaxseed significantly affected the composition of fatty acid profile and the shelf life of the produced meat. The fat content was changed in the experimental groups with 10% flaxseed supplementation (10.84% in MGB and 9.56% MLD) versus the control group. Despite the different concentrations of flaxseed, the best EPA/AA ratio was observed in the experimental groups fed with flaxseed supplementation for 3 weeks. The worst oxidative stability of meat samples (p < 0.05) was recorded in the experimental groups with the addition of flaxseed for 6 weeks, which was related to higher PUFA content in samples of the experimental groups and higher susceptibility of PUFAs to lipid oxidation. The oxidative stability of meat in the experimental group fed 5% flaxseed supplementation for 3 weeks was not affected.