THE DETERMINATION OF INTRAMUSCULAR FAT

Intramuscular fat is an important quality parameter. Its content in th e meat is usually determined by extraction (Soxhlet, Weibull-Stoidt an d with chloroform/methanol). The results of these methods cannot be co mpared one with another because of variations in the experimental cond itions. In the present paper we shall consider why the term IMF (intra muscular fat) is defined chemically as the triglyceride portion of the muscle. The advantages and disadvantages of the extraction methods me ntioned above are then discussed in relation to as accurate as possibl e a determination of IMF. We shall then show by means of extraction ex periments that none of the methods is able to give the precise IMF con tent but that extraction by the Soxhlet method gives the most realisti c value although it underestimates the content a little. The two other methods however, involving the accompanying extraction of non-fat por tions (phospholipids, free fatty acids), overestimate the IMF content considerably. Direct extraction with n-hexane in standardised form, e. g. in accordance with ISO 1444, is therefore recommended as a referenc e method for the analysis of IMF.