Do you know if the meat you eat is really fresh and safe?

Meat is a nutritious source of protein, and after slaughter, it undergoes post-mortem stages of curing and aging. Understanding the characteristics and freshness of each cut of meat will help you enjoy it more.

 

For us, meat is an important part of the table. Whether it’s raw or grilled, it tastes great, and nutritionally, there is no better source of protein than meat. In other words, it’s a precious gift of life. When we eat it, we don’t feel very guilty about killing an animal. When we see red meat with a little bit of blood on it, most of us want to eat it, and few people think it’s horrible. But the truth is, meat is an animal carcass. When a person dies, their body temperature drops and their flesh becomes cold and hard, and meat goes through the same process. We eat and enjoy the carcasses that are in the middle of this process.
Here’s how an animal carcass, or meat, goes through the process of postmortem stiffening and decomposition. When an animal is first slaughtered at a slaughterhouse, for a while, its flesh tries to stay in a similar state to when it was alive, barely surviving on a substance called ATP that was left in its muscles. ATP is the substance used to make energy, which is, in layman’s terms, akin to life force. However, this substance requires oxygen to be made, and since the animal is dead and unable to breathe, it cannot be made normally, and the remaining ATP quickly disappears. So, as a last resort, the muscles start the process of making ATP without oxygen, which means they start using a substance called glycogen that they have stored. The problem is that this process isn’t normal, so it doesn’t just produce ATP, it also produces an acid called lactic acid. If you continue to use glycogen to make ATP and acid, it will gradually build up in your muscles, causing them to become acidic. When your muscles become acidic to a certain extent, the enzymes that break down ATP become active, and ATP breakdown will occur. At the same time, the muscles, which have been maintained by ATP in a living state, begin to contract as their structure collapses in the process of being deprived of ATP. Like dominoes falling, the structures that make up the muscles collapse and pile on top of each other, and the muscles gradually lose their ability to hold water. As it loses water and continues to contract, this mass of flesh becomes very stiff, a state known as maximum post-contraction stiffness. As the muscles contract and stiffen, they continue to acidify because the process of using up ATP is happening at the same time. However, after another period of acidification, the enzymes that digest the proteins in the muscle are activated. As the enzymes digest the proteins, the tightly packed muscles loosen up again and the meat begins to tenderize, and the water retention, the ability of the meat to prevent moisture from escaping, returns, making it very juicy. This process is often referred to as the aging of meat, but it is actually the beginning of decay.
All living things, not just the cows, pigs, chickens, and fish we eat, go through this post-mortem stiffness when they die, and they all decay past the ripening stage. However, different animals go through all of these stages at different rates after slaughter. Larger animals and those that used a lot of muscle while alive are slower and take longer. The maximum post-mortem stiffening time is about a day for cattle, half a day for pigs, and two hours for chickens, and the meat is best eaten fresh and at its peak flavor. However, fish is a different story. Fish is usually eaten when it’s still in a post-mortem state, as its muscles aren’t naturally tightly bound. This is why sashimi, which is a freshly caught fish served on a plate, is often eaten to enjoy the chewy texture of post-consciousness. By understanding how the state of meat changes over time and considering the characteristics of each type of meat, you can better enjoy the meat that suits your tastes.