What is Aging for meat?You need to understand 3 things – Aging, Dry aging and Wet aging. To some extent they are interrelated. The basics are:
Aging – any meat left stored in a standard commercial cool room will 'age' i.e. The meat characteristics will change over time. Because most commercial operations only hang or store meat for relatively short periods i.e. a couple of days, then these changes are only minimal. Also there are technical issues with the normal cool room settings that mean the longest you can store meat with the normal temperature settings is 14 days. In Victoria this is in the food safety legislation. If someone says they 'dry age' for less than 14 days, you can bet they are not! They are 'aging' the meat in a normal coolroom.
Dry Aging – is the process of taking meat beyond that 14 day period. A small number of upmarket butchers and wholesalers have the required storage. You must keep the meat separate from your normal meats. This is for 2 reasons – you need to use different temperature, humidity and air flow settings to a normal cool room, and the second reason is you do not want cross contamination with your normal fresh meat. You need the coolroom to assist the cultivation of the 'good' bacteria (Thamnidium mould) that indicates the start of the aging process. This must be tested for, at about the 3 week point in the process. With the mould present, aging can continue until the 8th week. There are a number of laboratory tests that must be conducted before any meat can be sold from this process and the regulations are very stringent. Also the processing needs to be undertaken separately to normal fresh supplies.
To date NO ONE has dry aged lamb commercially. Watch this space!!!
Wet Aging - The less expensive alternative to dry aging is called wet aging. This cryovacced meat can be stored in refrigerators and allowed to age. Since the meat is packed in its own juices the enzymes will break down the connective tissues and make it more tender. However, because there will be no fluid loss the concentration of flavor that you get from dry aging is not as great. The big Caution – it does NOT extend the shelf life.
Dry Aging and why meat tastes so good.
Proteins, carbohydrates, and fats are the building blocks of living things, but they don't have much flavor in their natural state. They are bland to begin with. That's why we cook them, why we season them, why we transform them — to make them more appealing to us.
But sometimes we can get our food to make itself more delicious, by treating it in a way that creates favourable conditions for the enzymes that are already in the food to work together in a certain fashion.
Enzymes are molecules that exist in foods-and in microbes intimately involved with food-that can transform those basic, bland building blocks. They're nanocooks-the true molecular cooks. Dry-aging, ripening, and fermentation are all processes that take advantage of enzymes to make foods delicious before cooking.
Most meat, by contrast, is prepared for the market very quickly. The animal is slaughtered, the various parts of the muscle system are separated and packages, and then they're distributed. That's about it.
Dry-aging means that once the animal is slaughtered and butchered, portions of the carcass are allowed to rest in very carefully controlled conditions (cool temperatures, with relatively high humidity) for a period of time—often several weeks, and sometimes up to a couple of months.
When we create such conditions, we allow enzymes to do their work. And we end up with a complexity of flavor—savouriness, sweetness, some bitterness-that just wasn't there before. There's no cooking method that can generate the depth of flavor of a dry-aged piece of meat.
What happens is that enzymes in the meat's muscle cells begin to break down the meat's proteins, fats, and glycogen—a carbohydrate—into amino acids, fatty acids, and sugars. One amino acid generated by dry-aging—the most important and flavourful one, in fact—is glutamate, which is part of MSG. other amino acids have flavours somewhat similar to MSG; others still are sweet.
Dry-aging also causes it to lose some of its moisture. Meat begins at about 75 percent water; after dry-aging, it may go down to somewhere around 70 percent. It doesn't sound like much of a change, but what it means is that the flavours become more concentrated, and the tissue itself becomes more concentrated, too. Dry-aged meat is still juicy when you cook it, but the juices are even more delicious than usual.
In short, it's wonderful, delicious stuff. It's also really hard to get your hands on, and when you can find it, it's often very expensive—you really have to pay through the nose for it, because it's very expensive to produce. The meat has to be kept in a controlled environment for a long time, and that eats up money. And then you lose a fair amount of the meat's weight, too: you're evaporating moisture, and the surface of the meat begins to spoil, as well. It dries out, it develops unpleasant flavours, and sometimes it develops a bit of mold. It's not harmful, but it needs to be trimmed off before the meat can be sold.
Written by US food science writer and acclaimed author Harold McGee.