Section V: Methods for Determining WHC
Objective of Section V: To be able to describe commonly used methods to measure WHC and to know their advantages, disadvantages, and the key physical and chemical factors affecting these methods.
Tracking WHC by the various segments of the meat industry is difficult at best, and selecting methods to monitor WHC is not an exact science. The biggest challenge is to determine when and what aspect (for research, raw material characterization, process development, and monitoring for quality and process control) of WHC needs to be measured. Obviously, no one measurement is going to be effective. Rather, a "collective strategy" of identifying critical points (as in a safety HACCP plan) in the product flow diagram, which may start at the farm and include transportation, lairage, slaughter, chilling, fabrication, packaging, storage, freezing or thermal processing, etc. Multiple measurements can be taken at various segments of the operation and then collectively evaluated to help monitor those segments as well as the overall production scheme.
In many operations, a few measurements may be used to help monitor just one aspect of the production chain, such as the combined effects of chilling and pH decline on drip losses over a specified time and conditions, the purge accumulation in vacuum packaged cuts, or cooking losses. Care must be taken to avoid erroneous results as described in the following example. PSE, normal, and DFD retail cuts were displayed, and the purge loss in the package during display was calculated. Surprisingly, the data indicated that the PSE chops (not the high WHC, DFD meat) had the least drip loss and highest yields. What was not accounted for was the fact that the PSE had lost much more purge during pre-display storage in vacuum packages, thus the need for a collective analysis of multiple measurements.