Pork Products Have Digestible Indispensable Amino Acid Scores (DIAAS) That Are Greater Than 100 When Determined in Pigs, but Processing Does Not Always Increase DIAAS

Abstract

Background: Raw meat contains all indispensable amino acids (IAAs), but before human consumption, meat usually undergoes some degree of processing. Processing affects the 3-dimensional structure of proteins, which may affect amino acid (AA) digestibility and, therefore, overall protein quality. Objectives: The experiment aimed at determining digestible indispensable amino acid scores (DIAAS) for pork products, and to test the hypothesis that processing increases DIAAS. Methods: Ten ileal cannulated gilts (body weight: 26.63 ± 1.62 kg) were randomly allotted to a 10 × 10 Latin square design with ten 7-d periods. Ileal digesta were collected for 9 h on days 6 and 7 of each period. Nine diets contained a single pork product (i.e., raw belly, smoked bacon, smoked-cooked bacon, non-cured ham, alternatively cured ham, conventionally cured ham, and loins heated to 63°C, 68°C, or 72°C) as the sole source of AAs. A nitrogen-free diet was formulated to determine basal endogenous losses of AAs, which enabled calculation of standardized ileal digestibility (SID) of AAs. DIAAS were subsequently calculated according to the FAO. Results: All pork products had DIAAS >100 (as-is basis). Loin heated to 63°C had the greatest (P < 0.05) DIAAS for children 6 mo to 3 y and smoked-cooked bacon had the greatest (P < 0.05) DIAAS for children older than 3 y, adolescents, and adults. Raw belly, smoked bacon, and loins heated to 68°C and 72°C had a reduced (P < 0.05) DIAAS for both reference patterns compared with other proteins. Alternatively cured ham had greater (P < 0.05) DIAAS when compared with non-cured ham and conventionally cured ham. Conclusions: Bacon, ham, and loin are excellent proteins with DIAAS >100, and processing may sometimes, but not always, increase DIAAS.