D-3-hydroxybutyric acid test in Egg and Egg Products

The pasteurization of egg products is based on the use of not high temperatures, because egg proteins are sensitivity to heat. For this reason, the use of bad eggs, increases the health risk and reduces the shelf-life of the fresh egg products. The use of incubated or decayed eggs can be detected verifying the presence of some organic acids indicative of metabolic products and microbial decomposition such as succinic acid, lactic acid and D-3-hydroxybutyric acid. The best method currently highlighting this fraud is the test of D-3-hydroxybutyric acid, very low in fresh eggs (<1mg/kg), but much more high in the wastes of incubator. The analysis is generally carried out by extraction and gas chromatography.

The D-3-hydroxybutyric acid reacts, by an enzymatic reaction with the NAD⁺ and induces the formation of a pink color whose intensity, measured at 505 nm, is directly proportional to the concentration of D-3-hydroxybutyric acid in the sample. The result is expressed as ppm of D-3-hydroxybutyric acid.

Comparative tests on samples of mixed eggs where was add a D-3-hydroxybutyric acid standard, checked with CDR FoodLab® method, confirmed a very good alignment.