Tag: Per calculation

The protein efficiency ratio (PER) is a historical method for evaluating a protein's nutritional quality, based on how effectively it supports growth in test subjects. While it was once a standard for nutritional labeling, particularly in the U.S. and Canada, its use has been largely superseded by more advanced methods. This bioassay involves feeding a specific protein to a test animal, typically a rat, and then comparing the animal’s weight gain to its protein consumption over a defined period.

First introduced in 1919, the Protein Efficiency Ratio (PER) is a bioassay method used for assessing the nutritional value of a protein source. This metric is determined by a carefully controlled feeding study and is calculated by dividing the weight gain of a test subject by its protein intake over a specific period. While newer, more accurate methods exist, understanding how to calculate Protein Efficiency Ratio is still relevant for certain food regulations, particularly for infant formulas in the USA and for food claims in Canada.