Meat grading meat is divided into different grades according to the expected edible quality (such as appearance, tenderness, juiciness and flavor) and the expected production of marketable meat. Compared with meat inspection procedures, meat grading systems around the world vary greatly. These differences are largely due to different meat quality standards in different countries. For example, in the United States, cattle are mainly raised to produce steak and fed with high-quality grain feed to obtain a large amount of marbling in animal muscles. The high marbling level is related to the meat, which is more juicy, more flavor and more tender. In Australia, cattle are mainly raised to produce ground beef products, and the thinnest meat pieces are given the highest quality grade.
Some characteristics of meat used to evaluate quality and distribution grade include: carcass structure; Thickness of external fat; The color, texture and hardness of lean meat; The color and shape of bones; Marbling level; Flank stripes; And thin.
Retail cut meat
In American meat cutting, the whole carcass is usually processed into primary (primary) or primary (secondary) meat that is easier to manage in the packaging plant. This initial preparation simplifies meat sales by reducing changes in the incision. Raw and sub raw cuts are usually packaged and sold to retailers, who further process them into products in retail cases.
The physical changes associated with cooking meat are caused by the effect of heat on connective tissue and muscle protein.
In beef, the change in cooking temperature from 54 ° C or 130 ° f (very rare) to 82 ° C or 180 ° f (very well done) corresponds to the change in color from dark red or purple to light gray. These color changes are the result of myoglobin denaturation in meat. Denaturation is the physical expansion of proteins under the influence of extreme high temperature. Myoglobin denaturation makes the protein unable to bind oxygen, resulting in the color changing from bright cherry red of oxygenated myoglobin to brown of denatured myoglobin (equivalent to high iron myoglobin).
Food poisoning microorganism
Food poisoning microorganisms can cause health problems through poisoning or infection. Poisoning occurs when food poisoning microorganisms produce a toxin that can cause disease after ingestion. Different microorganisms produce several different toxins. These toxins usually affect cells in the intestinal wall, causing vomiting and diarrhea. Microorganisms that can cause food poisoning include Clostridium perfringens (Clostridium perfringens is present in cooked meat that is too hot, i.e. meat that is not stored, cooked or reheated at the appropriate temperature), Staphylococcus aureus (in pickled meat) and Clostridium botulinum (in canned meat).