New protein quality assessment discussed

A new method for determining the quality of dietary proteins proposed by the Food and Agriculture Organization of the United Nations (FAO, Rome) was discussed at the Protein Quality Symposium Conference at the IDF World Dairy Summit in Cape Town, 8-12 November 2012.

This new method, called Digestible Indispensable Amino Acids Score (DIAAS), will measure the digestibility of individual essential amino acids (EAA) in the small intestine as opposed to the previous focus on digestibility of proteins that was determined over the total digestive tract. The new method will also include determination of bioavailable lysine. Furthermore, for ingredients, the previously used truncation step will be disbanded. The new method will acknowledge that proteins with high levels of EAA can complement proteins with lower levels of EAA, thus ensuring that dietary intake of EAA in mixed diets meets the requirements.

“The high level of essential amino acids with high amino acids digestibility as well as the high lysine bioavailability in dairy proteins makes them a vital food ingredient for managing protein energy malnutrition and supporting growth in young children. Dairy proteins can be added to nutritional supplements currently used to prevent malnutrition and stunting. High quality proteins, such as those found in dairy, enable the use of a lower quantity of protein to meet dietary amino acid requirements. This is an excellent way to make the best use of current resources to prevent malnutrition. This work is particularly relevant to continents such as Africa and it was highly appropriate that it was presented here during a scientific session “, commented Dr. Paul J. Moughan, Distinguished Professor and Co-Director of the Riddet Institute, New Zealand.

“The new method (DIAAS) describes dietary protein quality accurately for the first time and thus highlights the superior quality of dairy proteins. With DIAAS, dairy proteins will have a protein quality measure 10-30% better than with the previous PDCAAS method. The proposed change in methods for protein quality assessment, is significant to the entire food industry and particularly in the nutrition therapy of vulnerable groups living in food insecure environments such as malnourished children, HIV infected individuals, and pregnant or lactating women. In the regions where food resources become scarce, protein quality becomes extremely important”, added Véronique Lagrange, U.S. Dairy Export Council, USA.

The newly proposed DIAAS is expected to be published shortly by FAO. It heralds a sweeping change in how dietary protein quality is determined and described. “For the first time in many years, the superior quality of dairy proteins will be apparent. Results will impact the dairy industry, food assistance programs and current standards in therapeutic nutrition practice, particularly for vulnerable populations. I encourage everyone in the industry to support the implementation of the new approach. DIAAS will demonstrate the true power of dairy proteins”, said Dr. Moughan.