In this blog post, we explore the scientific principles behind how meat deepens in flavor and texture through the aging process after slaughter.
Meat is an indispensable staple on our dining tables. Whether eaten raw or cooked, it always delivers rich flavor, and few foods rival meat as an exceptional source of protein. Beyond protein, meat is rich in essential nutrients like iron, zinc, and B vitamins, significantly aiding in maintaining stamina and building muscle. Thus, the key nutritional components of meat play a vital role in safeguarding modern health, possessing value that cannot be easily replaced by other foods. Therefore, meat is not merely an ingredient; it can be called a ‘precious gift from life’ that sustains our very existence.
Yet, when we actually eat meat, we rarely feel significant guilt about the fact that this food is the corpse of a living being. When seeing red meat with blood seeping through, most people first think ‘it looks delicious,’ not ‘it’s horrific.’ But let’s be clear: meat is the carcass of a slaughtered animal. Just as humans experience a drop in body temperature and gradual stiffening after death, animals also undergo a process called ‘postmortem rigor’ after slaughter, eventually leading to decay. We consume these corpses, caught in the midst of this physiological change, as food.
While this transformation of meat is known as ‘aging,’ its essence is also a stage in the dead organism’s progression toward decay. This process begins immediately after slaughter. When an animal is killed, the energy substance ATP remaining in its muscles temporarily acts to maintain the organism’s state. Simply put, ATP is a substance akin to vitality, requiring oxygen to be produced. However, since the animal can no longer take in oxygen after death, the remaining ATP gradually depletes. At this point, the muscles resort to anaerobic metabolism as a last resort to produce ATP without oxygen. During this process, glycogen breaks down, generating lactic acid, an acidic substance. As lactic acid accumulates in the muscles, acidification gradually occurs.
When the muscles become acidic, ATP-degrading enzymes become active. As a result, the muscle tissue structure breaks down and begins to contract. Simultaneously, the muscle’s ability to retain moisture gradually weakens. Over time, the muscle becomes increasingly firm; this state is called ‘maximum postmortem rigor.’ At this point, moisture escapes from the meat, causing it to dry out, and the tissue becomes tough. But it doesn’t stop there. Once acidification reaches a certain level, enzymes that break down muscle protein activate, slowly decomposing the protein. This process is precisely meat aging.
Aging doesn’t simply mean the meat gets old. As the protein-breaking enzymes work, the meat becomes more tender, its ‘water-holding capacity’—the ability to retain juices—is restored, and its flavor deepens. Aged meat develops a softer texture and a more pronounced, rich flavor, which is why many people prefer meat that has undergone this process. Accordingly, various aging techniques have been developed, and this process is regarded not merely as a cooking method but as an important science and art that maximizes the experience of ‘flavor’.
All animal-based foods we commonly consume—beef, pork, chicken, fish—undergo the stages of rigor mortis, aging, and decay after slaughter, each at its own pace. Larger animals with more muscle mass undergo this process more slowly, requiring longer maturation times. For example, beef takes about a day to reach maximum rigor mortis, pork takes half a day, and chicken takes about two hours. After this period, when the meat has matured sufficiently, it reaches its most ideal state in both flavor and texture.
Fish is somewhat different. Fish have soft muscle tissue with weak connective fibers, so rigor mortis begins quickly and ends shortly. This is why we eat fish like ‘sashimi’ when rigor mortis has just begun, enjoying its unique, springy texture. This isn’t simply a belief that fresher fish tastes better; it’s the result of a refined palate considering physiological changes.
Therefore, the timing immediately after catching fish is crucial, and consuming it during rigor mortis offers the most exceptional texture.
In conclusion, meat is an ingredient that requires understanding and utilizing the series of processes occurring after an organism’s death, beyond simple grilling or boiling, to truly bring out its best flavor. The principles of biological change are embedded within meat, and how we harness these changes alters the flavors we experience. Recognizing and respecting this process, as much as the life it embodies, is an attitude that transcends merely enjoying delicious food; it is a path to deep understanding and respect for food. The meat we encounter daily on our tables is thus a precious gift reaching us at the intersection of science, life, and taste.
