CAAV stands for the measure of the Critical Amino Acid Value. It is the sum of five critical essential amino acids of Lysine, Threonine, Tryptophan, Cysteine, Tryptophan, and Methionine) as a percent of crude protein.

It is a protein Quality measure and does not address quantity any more than the gross CP measure. It is a protein Quality measure that allows a buyer to evaluate the natural balance and gross levels of limiting essential amino acids in the soybeans or soybean meal.

It does not provide specific information for formulation. It provides a threshold where the probability of increase performance is likely and the addition of expensive synthetic amino acids can be minimized.

This is the formula used to calculate CAAV in soybean meal:

% Lysine + % Threonine + % Tryptophan + (% Methionine + % Cysteine )
divided by (/) Total Amino Acids
= Critical Amino Acid Value (CAAV)

Click here or on the Calculate tab on this website to enter the numbers from your sample and have your CAAV calculated today.

  • Lysine, Methionine, Tryptophan and Threonine are among first limiting essential amino acids.
  • Cysteine is well documented for sparing effect of methionine.
  • Lysine, Methionine, Tryptophan and Threonine are available as commercially produced synthetics.
  • Summation number suggests more completeness in nutritional value.

When amino acids are expressed as a PERCENT OF THE TOTAL SOYBEAN PROTEIN, the percentages of the 5 most limiting amino acids (5 CAAVs) DECREASE WITH INCREASING PROTEIN (and NEAAs increase, esp. glutamic acid & arginine). So, the protein in low crude protein soybeans is more concentrated in essential amino acids than that of high crude protein soybeans. Thus, the overall relationship found in this study between CP and Protein Quality as indicated by the sum of the 5 EAAs.

  • Although Brazilian soybeans are typically higher in crude protein than U.S. soybeans,
  • the lower protein U.S. soybeans are enriched in lysine, cysteine, methionine, and threonine, and can be expected to produce higher quality meal
  • that can meet animals’ essential amino acid needs
  • at lower dietary protein concentrations (N)
  • CAAV provides a simple numeric descriptor for assessing comparative value of soybean meals
  • CAAV provides an indication of critical amino acid concentration
  • Modifications may enhance CAAV as a tool to assess soybean meal value
  • Using CAAV as a selection tool can identify soybean meals of higher value in swine and broiler starter rations more consistently than crude protein.
  • CAAV information promotes the selection of soybean meals with higher concentrations of economically important amino acids

…and reduces the excess, unnecessary environmental nitrogen.


Additional Information