Long‐Chain n‐3 PUFA Content and n‐6/n‐3 PUFA Ratio in Mammal, Poultry, and Fish Muscles Largely Explain Differential Protein and Lipid Oxidation Profiles Following In Vitro Gastrointestinal Digestion

Abstract

Scope Muscle food characteristics (fatty acid profile, heme‐Fe, intrinsic antioxidants) that relate to the formation of (patho)physiological oxidation products during gastrointestinal digestion are investigated. Methods and Results Muscles (n = 33) from 18 mammal, poultry, and fish species, of which some are mixed with lard to standardize their fatty acid profile, are digested in vitro. Lipid oxidation is assessed by thiobarbituric reactive substances (TBARS), n‐3 PUFA derivative 4‐hydroxy‐2‐hexenal and propanal, n‐6 PUFA derivative 4‐hydroxy‐2‐nonenal and hexanal, and protein oxidation by carbonylation. Digests of n‐3 PUFA‐rich fish demonstrated the highest n‐3 PUFA oxidation, whereas digests of various poultry and rabbit muscles showed highest n‐6 PUFA oxidation, which correlated significantly with the n‐6/n‐3 PUFA ratio. Without lard addition, lipid oxidation is significantly higher in chicken and pork loin digests versus beef and deer digests, whereas the opposite occurred when these muscles are mixed with lard. Protein carbonylation correlates significantly with levels of TBARS and the sum of hydroxy‐alkenals in digests. The n‐6/n‐3 PUFA ratio correlates well with the 4‐hydroxy‐2‐nonenal/4‐hydroxy‐2‐hexenal ratio in digests. Conclusions Muscular fatty acid profiles largely explain type and extent of lipid and protein oxidation during gastrointestinal digestion. Red meat only stimulates oxidation when digested with specific fat sources.

WITHDRAWN: Pekin Duck Strain and Housing System Affect Chemical Composition, Fatty Acid Profile, and The Extent of Lipid and Protein Oxidation in Meat

“…Although those differences were not signi cant in all compared groups, apparently they contributed to different extent of lipid oxidation. On the contrary, Van Hecke et al [7] concluded the n-6 to n-3 ratio correlated more with PUFA oxidation than did the absolute content of PUFA, which was not con rmed in our study. Moreover, rearing conditions affect animal welfare and, consequently, the level of preslaughter stress and meat quality [13].…”

“…In our study, the recommended PUFA to SFA ratio was achieved in breasts and thighs of all experimental groups (from 0.91 to 1.07). However, in the current study, the ratio of n-6 to n-3 PUFA was several times greater than recommended (it was from 19.70 to 20.71) and determined in other studies [7,8,10,11,41]. This imbalance in the n-6 to n-3 PUFA ratio determined in our study was a consequence of diet, based mainly on maize and soybean that contained high levels of linoleic acid (n-6 fatty acid), and insu cient quantities of feeds that were sources of n-3 fatty acids.…”

“…However, these characteristics of duck meat provide favorable conditions for lipid and protein oxidation, measured by higher contents TBARS and PCC than in other species [7]. Since the extent of oxidation processes are dependent on the fatty acid pro le of meat [7], many studies investigated fatty acid pro les of different genotypes of duck, suggesting that genetic factors could in uence fatty acid composition of meat [4,8,9,10,11]. Considering that Pekin duck has many desirable characteristics, such as extraordinary body size, excellent muscle yield performance, and high intramuscular fat content [4], it is the preferred breed for commercial meat production.…”

“…In recent decades duck meat consumption has increased worldwide due to its high nutritive value, in particular due to high percentage of proteins and lipids, and high content of red muscle bers in meat [4,6]. Moreover, duck meat is a good source of polyunsaturated fatty acids, especially n-6 PUFA, has a favorable amino acid pro le, and, compared to other species, contains high level of Heme-Fe [6,7]. However, these characteristics of duck meat provide favorable conditions for lipid and protein oxidation, measured by higher contents TBARS and PCC than in other species [7].…”

“…Moreover, duck meat is a good source of polyunsaturated fatty acids, especially n-6 PUFA, has a favorable amino acid pro le, and, compared to other species, contains high level of Heme-Fe [6,7]. However, these characteristics of duck meat provide favorable conditions for lipid and protein oxidation, measured by higher contents TBARS and PCC than in other species [7]. Since the extent of oxidation processes are dependent on the fatty acid pro le of meat [7], many studies investigated fatty acid pro les of different genotypes of duck, suggesting that genetic factors could in uence fatty acid composition of meat [4,8,9,10,11].…”