In this blog post, we will take a look at the interesting process of aging and adding flavor to meat that we often eat after slaughter.
Meat is an important food that is indispensable to our diet. Whether eaten raw or grilled, it tastes good, and nutritionally speaking, there is no better source of protein than meat. In addition, meat is rich in essential nutrients such as iron, zinc, and B vitamins, which help maintain physical strength and build muscles. The main nutrients in meat play an important role in protecting the health of modern people and have a value that cannot be replaced by other foods. Therefore, meat is not just food, but a precious gift that is essential for sustaining our lives.
When we eat such meat, we don’t feel much guilt about killing the animal. When we see red meat with a little red blood on it, most of us just want to eat it, and few people think it’s horrible. But in fact, meat is also the carcass of an animal. Just as a person’s body cools and hardens as their body temperature drops after death, meat also undergoes rigor mortis and eventually rots over time after slaughter. We eat the carcasses that are in the process of rotting.
The process of an animal carcass, or meat, going through rigor mortis and rotting is as follows. When an animal is first slaughtered at a slaughterhouse, its flesh is still alive and struggling to stay alive, using a substance called ATP, which is stored in the muscles, to maintain a state similar to when it was alive. ATP is a substance used to produce energy, and in simple terms, it is similar to life force. However, this substance, ATP, is normally produced by receiving oxygen. However, since the animal is already dead and cannot breathe, ATP is gradually depleted, and the muscles begin the process of making ATP without oxygen as a last resort. In this process, the muscles break down a storage substance called glycogen, and along with ATP, they also produce an acidic substance called lactic acid, which gradually acidifies the muscles as lactic acid builds up.
When the muscles become acidic in this way, the enzymes that promote the breakdown of ATP become active. The muscles begin to contract as their structure collapses, and at the same time, they gradually lose their ability to retain water. Over time, the muscles become stiff, a condition known as rigor mortis. In this process, the meat becomes firm, moisture is lost, and it gradually becomes dry. As the muscles contract and become firm, the process of making remaining ATP continues, so the muscles continue to acidify. However, when acidification progresses to a certain extent, enzymes that digest muscle proteins are activated and the proteins are gradually broken down.
This change is understood as the process of ripening, but it is also a sign that decay has begun. As the protein-digesting enzymes work, the meat gradually softens and regains its juiciness, making it even more delicious. When the meat is properly aged, it becomes especially flavorful and its texture softens, giving it a chewy texture. For this reason, many people prefer to eat aged meat, and they study various aging methods to bring out the best flavor.
All living things, including the cows, pigs, chickens, and fish that we eat, go through this maximum rigor mortis and then decay after the ripening stage. However, the speed at which all these stages take place after slaughter varies from animal to animal. Animals that are large and have used a lot of muscle while alive are slow, so it takes a long time for them to ripen. For example, the time it takes for maximum rigor mortis to set is one day for cattle, half a day for pigs, and two hours for chickens, and meat that has been left for a little longer than this is said to be fresh and at its most delicious.
Fish is different. Fish has soft muscle tissue and loose connective tissue, so it has a shorter period of rigor mortis. “Live sashimi,” which is sashimi made from fish that has just been caught and eaten raw, is intended to enjoy the chewy texture of the fish after rigor mortis has begun. Therefore, it is common to eat sashimi to enjoy the texture of fish that has just been caught and is in a state of rigor mortis.
In conclusion, if you understand the characteristics of each meat and make good use of its state changes, you can enjoy your favorite meat dishes to the fullest.
