As pork producers continue to improve growth efficiency and push market weights heavier one question keeps coming up on the processing side: are carcasses getting too big for our current chilling systems?
It’s a fair concern. When things get bigger and denser, they cool more slowly. Most of us have seen this play out at home or at an event. Imagine the end of an FFA banquet…there’s a large pan of pulled pork left over, and it gets placed in the refrigerator to chill. The outside cools down quickly, but the center stays warm for a long time. That’s a problem because of what we call the “danger zone”: a temperature range where bacteria grow rapidly.
While food safety is always top of mind, the concern in pork carcasses is a little different. In intact muscles like the ham or shoulder, we worry less about bacterial growth in the interior. Instead, the bigger issue is how temperature interacts with muscle biology early postmortem. As pH declines after harvest, if muscle temperature remains high for too long, proteins can become denatured. When that happens, they lose their ability to hold water.
The result? Paler meat and reduced water-holding capacity, traits that can impact both fresh pork quality and further processing performance. This becomes especially important for the ham, where much of the product is destined for curing and further processing into items like deli ham. If proteins are compromised early, it can lead to weaker cured color and a drier final product after cooking. For processors, that’s a real economic concern.
So, what did we do to evaluate this?
At the University of Illinois Meat Science Lab, we tracked chilling in some very large pigs, around 400 pounds live weight. While the chilling in our facility is effective, it doesn’t have the advanced blast chilling systems found in many commercial plants. This meant that we were already in less than perfect chilling conditions and further stressing the system with some heavy carcasses. We monitored how quickly different muscles cooled and evaluated traits relevant to further processing.
As expected, larger carcasses chilled more slowly than smaller ones. We also saw differences across primals. Hams and shoulders cooled more slowly than loins. These effects stacked on top of each other, meaning that the hams from the heaviest pigs were the slowest to chill.
But here’s the good news.
Even under these less-than-ideal chilling conditions, we did not observe meaningful negative effects on ham color or processing characteristics. In other words, while heavier carcasses cooled more slowly, that slower chilling did not translate into reduced product quality in our study.
So, what’s the takeaway? For now, it appears that pigs have not outgrown our ability to chill them effectively. That said, this isn’t a “set it and forget it” situation. As I often remind my graduate students, much of the work in fresh meat science is about monitoring—identifying potential issues before they become real problems.
Carcass weights will likely continue to increase, and processing systems will need to keep pace. Staying ahead of these changes ensures that improvements in production efficiency continue to deliver high-quality pork products all the way through the supply chain.
For now, bigger pigs are still keeping their cool—but we’ll be watching closely.
Want to know more? Check out our publications about these pigs:
Pork Ham and Belly Processing Traits With Increasing Carcass Weight by Joe Metz and others
We appreciate support from the National Pork Board, whose investment in meat quality research like this helps ensure that production gains translate into high-quality pork products.
