As Gillian Riley (1993) has written: ‘The idea that spices were used in the Middle Ages to mask the flavour of tainted meat has been expressed with considerable conviction by many writers about food and cookery.’
The same author demonstrates that:
no convincing evidence has been produced to support this idea;
in particular, the alleged recommendations in medieval texts to use spices for this purpose cannot be found;
the supposition that the ‘tainted meat’ theory is the only way of accounting for heavy consumption of spices in the Middle Ages is based simply on a misconception, since consumption of spices in that period was not unduly heavy—and indeed could not have been, given their cost;
detailed evidence about how cattle were slaughtered, how meat was sold, how cooks kept it and cooked it in particular places at particular times—all this can now be studied in detail and produces no evidence in support of the myth.