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An experiment was conducted to test the hypothesis that meat products have digestible indispensable amino acid scores (DIAAS) >100 and that various processing methods will increase standardised ileal digestibility (SID) of amino acids (AA) and DIAAS. Nine ileal-cannulated gilts were randomly allotted to a 9 × 8 Youden square design with nine diets and eight 7-d periods. Values for SID of AA and DIAAS for two reference patterns were calculated for salami, bologna, beef jerky, raw ground beef, cooked ground beef and ribeye roast heated to 56, 64 or 72°C. The SID of most AA was not different among salami, bologna, beef jerky and cooked ground beef, but was less (P < 0·05) than the values for raw ground beef. The SID of AA for 56°C ribeye roast was not different from the values for raw ground beef and 72°C ribeye roast, but greater (P < 0·05) than those for 64°C ribeye roast. For older children, adolescents and adults, the DIAAS for all proteins, except cooked ground beef, were >100 and bologna and 64°C ribeye roast had the greatest (P < 0·05) DIAAS. The limiting AA for this age group were sulphur AA (beef jerky), leucine (bologna, raw ground beef and cooked ground beef) and valine (salami and the three ribeye roasts). In conclusion, meat products generally provide high-quality protein with DIAAS >100 regardless of processing. However, overcooking meat may reduce AA digestibility and DIAAS. [ABSTRACT FROM AUTHOR]

True ileal digestibility (TID) values of amino acid (AA) obtained using growing rats are often used for the characterisation of protein quality in different foods and acquisition of digestible indispensable amino acid scores (DIAAS) in adult humans. Here, we conducted an experiment to determine the TID values of AA obtained from nine cooked cereal grains (brown rice, polished rice, buckwheat, oats, proso millet, foxtail millet, tartary buckwheat, adlay and whole wheat) fed to growing Sprague–Dawley male rats. All rats were fed a standard basal diet for 7 d and then received each diet for 7 d. Ileal contents were collected from the terminal 20 cm of ileum. Among the TID values obtained, whole wheat had the highest values (P <0·05), and polished rice, proso millet and tartary buckwheat had relatively low values. The TID indispensable AA concentrations in whole wheat were greater than those of brown rice or polished rice (P <0·05), and polished rice was the lowest total TID concentrations among the other cereal grains. The DIAAS was 68 for buckwheat, 47 for tartary buckwheat, 43 for oats, 42 for brown rice, 37 for polished rice, 20 for whole wheat, 13 for adlay, 10 for foxtail millet and 7 for proso millet. In this study, the TID values of the nine cooked cereal grains commonly consumed in China were used for the creation of a DIAAS database and thus gained public health outcomes. [ABSTRACT FROM AUTHOR]

An experiment was conducted to compare values for digestible indispensable amino acid scores (DIAAS) for four animal proteins and four plant proteins with values calculated as recommended for protein digestibility-corrected amino acid scores (PDCAAS), but determined in pigs instead of in rats. Values for standardised total tract digestibility (STTD) of crude protein (CP) and standardised ileal digestibility (SID) of amino acids (AA) were calculated for whey protein isolate (WPI), whey protein concentrate (WPC), milk protein concentrate (MPC), skimmed milk powder (SMP), pea protein concentrate (PPC), soya protein isolate (SPI), soya flour and whole-grain wheat. The PDCAAS-like values were calculated using the STTD of CP to estimate AA digestibility and values for DIAAS were calculated from values for SID of AA. Results indicated that values for SID of most indispensable AA in WPI, WPC and MPC were greater (P <0·05) than for SMP, PPC, SPI, soya flour and wheat. With the exception of arginine and tryptophan, the SID of all indispensable AA in SPI was greater (P<0·05) than in soya flour, and with the exception of threonine, the SID of all indispensable AA in wheat was less (P<0·05) than in all other ingredients. If the same scoring pattern for children between 6 and 36 months was used to calculate PDCAAS-like values and DIAAS, PDCAAS-like values were greater (P<0·05) than DIAAS values for SMP, PPC, SPI, soya flour and wheat indicating that PDCAAS-like values estimated in pigs may overestimate the quality of these proteins. [ABSTRACT FROM AUTHOR]

To determine values for the digestible indispensable amino acid score (DIAAS), it is recommended that ileal amino acid (AA) digestibility values obtained in growing pigs are used to characterise protein quality in different foods. Therefore, an experiment was conducted to determine the standardised ileal digestibility (SID) of AA in eight cereal grains (yellow dent maize, Nutridense maize, dehulled barley, dehulled oats, polished white rice, rye, sorghum and wheat) fed to pigs, where SID values in pigs can be used to calculate approximate DIAAS values in humans. In the present experiment, twenty-four barrows with a T-cannula inserted in the distal ileum were allotted to eight diets and fed for three periods to give a total of nine replicate pigs per diet. Each period lasted 14 d, and ileal digesta samples were collected on days 13 and 14. Among the SID values obtained for all cereal grains, values for total indispensable AA were greatest (P< 0·05) in rice and lowest (P< 0·05) in rye and sorghum. The concentrations of SID indispensable AA in rice were less (P< 0·05) than in dehulled oats, but greater (P< 0·05) than in the other cereal grains, and the concentrations of SID indispensable AA in Nutridense maize were greater (P< 0·05) than in yellow dent maize and sorghum, but less (P< 0·05) than in the other cereal grains, except rye. In conclusion, results indicate that to meet dietary requirements for AA in humans, diets based on yellow dent maize or sorghum require more AA supplementation than diets based on other cereal grains. [ABSTRACT FROM PUBLISHER]

Two experiments were conducted to test the hypothesis that processing of meat proteins increases the Digestible Indispensable Amino Acid Score (DIAAS). In Exp. 1, 10 pigs (26.62 ± 1.62 kg) with a T-cannula in the distal ileum were randomly allotted to a 10 x 10 Latin square with 10 diets and ten 7-d periods. In Exp. 2, 9 cannulated pigs (35.50 ± 3.77 kg) were randomly allotted to a 9 x 8 Youden square with 9 diets and eight 7-d periods. Meat proteins (Table 1) were included in the diet as the only source of AA. The DIAAS for each meat protein was calculated using the Food and Agriculture Organization of the United Nations (FAO) established reference patterns for children 6 mo to 3 yr and older children, adolescents, and adults. Data were analyzed using PROC MIXED of SAS in a randomized complete block design with the pig as the experimental unit. In Exp. 1, all meat proteins had a DIAAS greater than 100% regardless of the reference pattern. For both reference patterns, the DIAAS for smoked-cooked bacon was greater (P < 0.05) than for raw belly and smoked bacon, the 2 cured hams had a numerically greater DIAAS than the uncured ham, and the medium loin had a greater (P < 0.05) DIAAS compared with the medium-well and well-done loins. In Exp. 2, most proteins had a DIAAS value greater than 100%. For both reference patterns, raw ground beef had a greater (P < 0.05) DIAAS than cooked ground beef, and medium ribeye roast had a greater (P < 0.05) DIAAS than medium-rare and well-done ribeye roasts. In conclusion, curing and moderate cooking may increase DIAAS, whereas grinding meat prior to some, but not all, cooking methods or overcooking may reduce the DIAAS of meat proteins. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to determine standardized ileal digestibility (SID) of amino acid (AA) and digestible indispensable amino acid scores (DIAAS) for brown rice protein concentrate (BRPC), pea protein concentrate (PPC), two rapeseed protein isolates (RSP-1 and RSP-2), soy protein isolate (SPI), and whey protein isolate (WPI). Seven cannulated barrows (36.51 ± 1.61 kg) were randomly allotted to a 7 × 7 Latin square design and fed a diet containing each protein as the sole source of AA. A nitrogen-free diet was also used. The DIAAS was calculated for children from 6-mo to 3-yr and persons >3-yr. Data were analyzed using PROC MIXED of SAS in a randomized complete block design with pigs as the experimental unit. Among proteins, WPI had the greatest (P < 0.05) SID of all indispensable AA (IAA), except Lys and Thr, and RSP-1 had the least (P < 0.05) SID of most IAA. The SID of all AA, except Leu and Met, did not differ between RSP-2 and SPI, and the SID of all IAA, except Arg and Lys, was greater (P < 0.05) for RSP-2 than for PPC and BRPC. For DIAAS (Table 1), RSP-2 was the only protein with a DIAAS greater than 100 for children 6-mo to 3-yr, and both RSP-2 and WPI had a DIAAS greater than 100 for persons >3-yr. For both reference patterns, the DIAAS for RSP-2 and WPI was greater (P < 0.05) than for SPI. The DIAAS for RSP-1 was less (P < 0.05) than for SPI and greater (P < 0.05) than for PPC, which had a DIAAS greater (P < 0.05) than BRPC. In conclusion, RSP-2 resulted in an excellent quality protein for persons >6-mo, and WPI is an excellent quality protein for persons >3-yr. [ABSTRACT FROM AUTHOR]