Diet authentication in ruminants from the composition of their products and tissues

Abstract

There is currently an increased consumer demand for information on herbivore production factors, particularly animal diet. To meet these demands, farmers and commercial entities develop specifications via quality labels. There is therefore a need for analytical tools that may guarantee that the specification commitments have been fully met or to help constructing them. The nature of the diet strongly influences the composition of the animal tissues and products, which is due to specific compounds that are directly transferred from the feed to the end product or that are transformed or produced by ruminal microorganisms or the animal’s metabolism under the effect of specific diets. Some of these compounds can therefore be used as diet markers. Moreover, differences in the meat and milk composition induce diffe-rences in their optical properties, therefore in their spectral features, which can also be used for diet authentication. This paper reviews the different approaches that have been investigated, some leading results concerning the comparison of contrasting feeding situations, together with the persistence and latency of appearance of some diet markers in the event of animal diet changes, and lastly some examples of implementation in the field with farmers that are interested in such methods.