What we would think of as a beef animal had the double purpose of being a working or draught animal that could pull heavy loads. There is an old adage, "A year to grow, two years to plough and a year to fatten." The beef medieval people would have eaten would have been a maturer, denser meat than we are used to today. I have always longed to try it. The muscle acquired from a working ox would have broken down over the fattening year and provided wonderful fat covering and marbling. Given the amount of brewing that took place, the odds are that the animals would have been fed a little drained mash from time to time. Kobe beef, that excessively expensive Japanese beef, was originally obtained from ex-plough animals whose muscles were broken down by mash from sake production and by massage. 'd like to think our beef might have had a not dissimilar flavour.
Clarissa Dickson Wright,
A History of English Food (The Medieval Larder)