Comparison in the Composition of Fatty Acids of Two Cuts of Caiman latirostris Meat Bred in Captivity: Perspectives for a Greater Valorization of the Resource

Abstract

Fat is the most variable component in the chemical composition of the meat of many species; since its disposition is strongly determined by the balance between intake and metabolic requirements. Strong differences in lipid composition between muscles have been reported in different domestic species and in wild species raised in captivity such as: capybara, rabbit, Nile crocodile, otter, etc. In alligators, fat represents 6% of the weight of the carcass and is constituted mainly of unsaturated fatty acids of long chains with low cholesterol content. Little is kwon about the distribution of these fatty acids between the different parts carcass, as well as nutritional differences between the different muscles. The objective of this work was to evaluate fatty acid profile of meat of M. ílio-ischio caudalis and M. occipito-cervicalis medialis (tail and neck respectively) from Caiman latirostris (Broad-snouted caiman) bred in captivity, with the aim of establishing differences between these parts that can provide greater economic benefits in the production system of C. latirostris meat. Both cuts were taken from animals produced by Proyecto Yacaré/Yacaré Santafesinos. The fatty acid composition in the two cuts was determined by the methyl esters method and calculated the proportions: PUFA/SFA, n-6/n-3, and Δ-9-desaturase activity. We found evidence that the profile of individual fatty acids in tail and neck cuts are different for fatty acids: C14:0, C16:0, C18:0, C18:1, C18:2, C20:5 and C22:6. The polyunsaturated fatty acids (C18:2, C20:5 and C22:6) were higher in the neck than in the tail, which presented higher values of short chain saturated fatty acids (C14:0, C16:0). These differences, especially in C18:0, C18:1, C18:2 and C20:5 affect the sum of fatty acids: SFA, MUFA, PUFA, n-6 and n-3; as well as the proportions: PUFA/SFA and n-6/n-3, which presented higher values in the neck tissue. The tail showed high Δ-9-desaturase activity compared to the neck, which suggests that the high presence of unsaturated fatty acids in the neck are essentially due to their direct incorporation through diet and not to de novo synthesis. This results suggest that fatty acids distribution varies between cuts; furthermore, this difference may be related to muscle function. High presence of polyunsaturated fatty acids in the neck can provide added value to this cut of the carcass, since it can be sold as a meat with cardioprotective characteristics and nutraceutical.