Sunflower meal, which is the co-product derived from sunflower seeds after oil extraction, has a high concentration of digestible amino acids (AA) and fiber. The nutritive value and quality of sunflower meal is partially dependent on the degree of dehulling, the variety of the sunflower, and the oil extraction process. Sunflower seeds are initially de-hulled and then partially de-oiled using a mechanial prepress procedure. A second de-oiling procedure is performed using a solvent extraction procedure or by usign a second mechanical expelling procedure. The prepress-solvent extraction procedure results in production of sunflower oil and sunflower meal that contains 1 to 3% oil, whereas the double-press procedure results in production of sunflower oil and a sunflower product that contains 5 to 10% residual oil and commonly is referred to as sunflower expellers. Some of the hulls may be added back to the sunflower meal or the sunflower expellers resulting in differences in concentrations of total dietary fiber among sources.

The apparent ileal digestibility and the standardized ileal digestibility (SID) of crude protein (CP) and AA in individual sources of partially de-hulled sunflower meal fed to pigs have been reported. However, there are no comparative values for the SID of AA in sunflower meal produced in different parts of the world, and it is not known if the SID of AA in sunflower meal are different from those in sunflower expellers. Therefore, the objective of the current study was to test the hypothesis that there is no difference in the SID of CP and AA in different sources of sunflower meal and sunflower expellers obtained from different countries.

Rodriguez, D. A., Su A Lee, and H. H. Stein. 2020. Nutrition Know-How: High-Shear Dry Soybean Expellers. Pork Magazine, On-line edition, Aug. 2020. Link to full text.

In most AA digestibility experiments collection bags are changed at least every 30 min and the collected ileal digesta are stored at –20 °C to prevent microbial degradation of proteins. Other attempts to reduce microbial activity in digesta include adding acids to collection bags to reduce the pH in ileal digesta. Acids may also be added to collection pitchers. However, in some experiments, no attempt to reduce pH is made because it is assumed that the rapid reduction in temperature after collection is sufficient to prevent microbial degradation of proteins.

To our knowledge, there is, however, no information about the necessity of adding acids to collected digesta and it is not known if values for apparent ileal digestibility (AID), basal endogenous losses of AA, or standardized ileal digestibility (SID) of AA are influenced by addition of acids to digesta. Therefore, the objective of this experiment was to test the null-hypothesis that values for AID, basal endogenous losses, and SID of AA are not influenced by addition of acids to ileal digesta collection bags or to collection pitchers.

Breakfast cereals are usually consumed with milk as a breakfast meal. To meet requirements for amino acids (AA), higher quality proteins are needed to complement the protein in cereals to provide a meal that is adequate in all indispensable AA. The digestible indispensable amino acid score (DIAAS) method used to determine protein quality allows for calculation of the protein value of individual ingredients and mixed meals consisting of several proteins. Values for DIAAS are based on values for apparent ileal digestibility (AID) of AA that are corrected for the basal endogenous loss of each individual AA, resulting in values defined as standardized ileal digestibility (SID). Values for SID of AA are additive in mixed meals because these values are independent of basal endogenous losses. Consequently, it is expected that DIAAS obtained for individual food ingredients are additive in a mixed meal, but data to demonstrate this have not been reported. Therefore, the objective of this experiment was to test the hypothesis that AA in milk complement AA in breakfast cereals to provide a balanced meal and that DIAAS in individual foods are additive in a combined meal.  

Cristobal, Minoy, Jessica P. Acosta, Su A Lee, and Hans H. Stein. 2020. A new source of high-protein distillers dried grains with solubles (DDGS) has greater digestibility of amino acids and energy, but less digestibility of phosphorus, than de-oiled DDGS when fed to growing pigs. Journal of Animal Science, 2020, Vol. 98, No. 7, 1–9. doi:10.1093/jas/skaa200.

Bailey, Hannah M., John K. Mathai, Eric P. Berg, and Hans H. Stein. 2020. Most meat products have digestible indispensable amino acid scores that are greater than 100, but processing may increase or reduce protein quality. British Journal of Nutrition (2020), 124, 14–22. doi:10.1017/S0007114520000641. Link to full text.

Lagos, Vanessa L., Hans H. Stein. 2020. Torula yeast has greater digestibility of amino acids and phosphorus, but not energy, compared with a commercial source of fish meal fed to weanling pigs. Journal of Animal Science, 2020, 1-9. doi:10.1093/jas/skz375. Link to full text.

Velayudhan, Deepak Ettungapladi , Manik M. Hossain, Hans H. Stein, and C. Martin Nyachoti. 2019. Standardized ileal digestibility of amino acids in canola meal fed to gestating and lactating sows. Journal of Animal Science, 2019, 4219–4226. Link to full text.

Bailey, H. M., H. H. Stein. 2019. Can the digestible indispensable amino acid score methodology decrease protein malnutrition. Animal Frontiers, Volume 9, Issue 4, October 2019, Pages 18–23. Link to full text.