hello everyone my name is Juliana Martins I work at the Stein Monogastric Nutrition Laboratory, I'm a visiting scholar here and I have been conducting different experiments at the farm, evaluating protein quality for human foods using pig as a model. so today I'm going to present a poster that we presented in the midwest meeting, that is titled Digestible indispensable amino acid scores (DIAAS) in pork products.

Protein malnutrition is a major problem in which many individuals, particularly children and the elderly, do not consume enough protein and amino acids to meet their nutritional needs. Animal proteins have greater protein quality than plant protein, and pork is one of the most produced meats in the world, also the protein quality is expected to be high in all pork products.  The “Digestible Indispensable Amino Acid Score” (DIAAS) method measures protein quality in human foods. However, values for DIAAS are not available for some pork products.

Therefore, the objective of this experiment was to determine the standardized ileal digestibility (SID) and DIAAS values for nine pork products. So for this study we used 10 experimental diets, on each diet, 9 pork products were used, being them Three types of pork cuts: back ribs, tenderloin, and shoulder butt, three types of Italian hams: Coppa, prosciutto, and speck, and three types of sausages: chorizo, Italian, and bratwurst, and we also had one nitrogen-free diet that we use for accounting basal endogenous losses of amino acids.

For this study we had nine ileal cannulated pigs with body weight of 50.3 kilogram and they were assigned to a yoden square design where we had six replicated pigs per diet and each Pig eated one diet per period each period lasts 7 days with 5 days of adaptation of the diet and collections on the day 6 and 7. at the end of the experiment we analyzed all ingredientes diets and ileal digesta for amino acids protein in dry matter and we calculated the standardized ileal digestibility of protein and amino acids and diets.

Moving on to the results, For children from 6 months to 3 years old and individuals older than 3 years old, prosciutto had greater DIAAS compared with all other pork products, and tenderloin and Coppa had greater DIAAS than back ribs, shoulder butt, chorizo, and bratwurst. 

The observation that back ribs and shoulder butt had lower DIAAS than tenderloin is due to the fact that tender cuts with less connective tissues tend to have greater concentrations of indispensable AA with less non-nitrogen content that may improve DIAAS. It is possible that if back ribs and shoulder butt were slow-cooked, protein quality would be comparable to the tenderloin.

There was no limiting AA for all pork products, with the exception that chorizo had sulfur amino acids: methionine + cysteine as the first limiting AA for children from 6 months to 3 years old.

For both age groups, prosciutto had greater DIAAS compared with all other pork products. The observation that prosciutto had DIAAS values greater than in Coppa is likely because prosciutto was made from the hind leg of the pig, which contains less connective tissue than the pork shoulder used to make Coppa. In addition, the prosciutto was non-smoked, which may contribute to the greater DIAAS values for this protein because processing may decrease DIAAS if a protein is overheated. 

Speck was made from lightly smoked prosciutto ham in a 6-month-curing process and had the lowest DIAAS among all Italian hams. It is possible that the curing process that was made for an extended period of time may have caused proteins to lose their nutritional value.

Therefore, results for DIAAS for all Italian hams demonstrated that these proteins can be considered “excellent” protein quality. 

To our knowledge, this is the first time DIAAS values for sausages are measured. All sausages were considered "good" or "excellent" quality proteins for individuals older than 6 months. Chorizo and bratwurst had lower DIAAS than Italian sausage, probably because of processing or the addition of other ingredients such as fillers, binders, and spices that may dilute the AA content and lower the overall protein quality. Therefore, results for DIAAS for all Italian hams demonstrated that these proteins can be considered “excellent” protein quality. 

In conclusion, All pork products have “good” or “excellent” protein quality for individuals older than 6 months, indicating that these food ingredients may be used to complement lower-quality proteins and provide a meal with all indispensable AA. Thank you very much, and if you are interested in our research, please visit our website.