What is PDCAAS?

Posted on June 15, 2009 in Diet for Diseases, Diet-Health, Diet-Types

PDCAAS (Protein Digestibility Corrected Amino Acid Score) is a standard used to know the quality and efficiency of protein in a particular food. The PDCAAS (Protein Digestibility Corrected Amino Acid Score) evaluation procedure is considered to be superior to other methods.

PDCAAS has been adapted by the U.S. Food & Drug Administration (FDA), the United Nations Food & Agricultural Organization (FAO) and the World Health Organization (WHO) as the preferred method for evaluating food protein.

How PDCAAS works?

PDCAAS measures the quality of a food protein based on the amino acid requirements of 2 – 5 year olds, who are considered the most protein requiring age group.

The amount of different amino acids in a particular food is calculated. It is then compared to the amount of essential amino acids required by a 2 -5 year old. The following is the requirement of different amino acids for a 2 – 5 year old.

Amino acid                              Requirement(mg/g crude protein)                                                                                                                                   Isoleucine                                     28
Leucine                                         66
Lysine                                           58
Total sulfur amino acids                  25
Total aromatic amino acids              63
Threonine                                     34
Tryptophan                                   11
Valine                                           35
Total                                            320

The digestibility of the food protein is also taken into account. That is, how much of the protein is absorbed by the body after digestion. The fecal method is used to evaluate digestibility.

A food must have all the essential amino acids in required amount to be considered a good source of protein. So, only the amino acid with the least presence in the food is taken into consideration for getting PDCAAS.

For example, a food contributes only 36 mg/g of Leucine to the body, but can contribute more than required amounts of other amino acids. Still, only the 36 mg/g of Leucine is considered to get PDCAAS.

The highest possible PDCAAS is 1.0. A score of 1.0 means that after digestion of the food, it provides 100% or more of the recommended amount of essential amino acids per unit of protein.

A score above 1.0 is rounded off to 1.0. This is because excess protein is not absorbed by the body. It is either converted into fat or thrown out as waste.

PDCAAS of various foods

Here is a list of the PDCAAS of various foods

Whey                                                                           (1.0)
Egg white                                                                     (1.0)
Casein                                                                         (1.0)
Milk                                                                             (1.0)
Soy protein isolate                                                        (1.0)
Beef                                                                           (0.92)
Soybean                                                                     (0.91)
Tubercles                                                                   (0.74)
Vegetables                                                                 (0.74)
Legumes in general                                                         (0.69)
Kidney beans                                                               (0.68)
Rye                                                                           (0.68)
Cereals and derivatives                                                    (0.58)
Whole wheat                                                                (0.54)
Lentils                                                                         (0.52)
Peanuts                                                                       (0.52)

If you are looking for a protein supplement, look for the PDCAAS score on the box. If it is less than 1.0, do not take it.

Comments

One Response to “What is PDCAAS?”

  1. Babu.A.A on October 6th, 2009 2:01 pm

    Its a valuable information for me.

    Thanks.

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