Shortening as a factor in meat ageing

Summary. Shortening during the slow and rapid phases of rigor mortis onset determines largely the extent to which beef ages. For meat stored at 15°C for 3 days, shear‐force values are uniformly low at shortenings of 0% to 20% of the freshly excised muscle length. However, there is a four‐ to five‐fold increase in toughness as shortenings proceed from 20% to 40%. This is followed by a decline in toughness as shortenings increase further from 40% to 55%. With increasing shortenings beyond 20%, progressive decreases occur in the extent to which meat ages until at 40% shortening, ageing has declined to zero.