Proximate composition, energy value, and lipid quality in loin in different weight classes of pirarucu (Arapaima gigas) from fish farming

The study aimed to determine the fatty acids profile, omegas, and lipid quality in loin in different weight classes of pirarucu (Arapaima gigas). A total of six pirarucu loin samples were used and sent to the laboratory by weight class, 1 (< 8 kg), 2 (8.1 to 11 kg), 3 (11.1 to 14 kg), 4 (14.1 to 18 kg), 5 (18.1 to 23 kg), 6 (23.1 to 32 kg), and 7 (> 32 kg). The experimental design was completely randomized, with processing conducted out in triplicate. Data were submitted to analysis of variance (ANOVA) to assess differences in pirarucu loin between weight classes. When ANOVA was statistically significant (α = 0.05), the averages were compared using Tukey’s test. Weight class 7 showed higher values of mineral matter = 1.43, crude protein = 28.93, and energy = 526.35 KJ∙100g-1. However, weight class 2 showed a higher value of total lipids, 2.60, and moisture, 78.19. The pirarucu loin showed essential fatty acids, EPA, DHA, AA, and ALA, while weight classes 4 and 5 had the highest percentages of PUFAs. However, all weight classes expressed high values in omegas 3, 6, 7, and 9. There is no need to market heavier fish, as pirarucu loin in lighter weight classes 3 and 4 already meet the nutritional demand of the market.