The color change in meat due to oxygen exposure is primarily due to what pigment?

The pigment responsible for the color change in meat when exposed to oxygen is myoglobin. Myoglobin is a protein found in muscle cells, and it has a crucial role in storing oxygen for muscle metabolism. When meat is cut and exposed to air, oxygen interacts with the myoglobin, leading to a transformation in its chemical structure. This process causes myoglobin to oxidize, resulting in the formation of oxymyoglobin, which gives the meat a bright red color that is often associated with freshness.

As oxygen continues to interact with myoglobin over time, especially if the meat is not consumed promptly, it can further oxidize to metmyoglobin, which has a brownish color. This change in color can affect consumers' perceptions of the meat's freshness and quality.

Although other pigments such as hemoglobin, which is found in blood, also carry oxygen, it is myoglobin that is specifically linked to the color observed in consumer meat products. Carotene, known for its presence in fruits and vegetables, and melanin, typically associated with skin pigmentation, are not relevant to the color changes in meat. Thus, myoglobin is the primary pigment associated with the observed color changes in meat upon exposure to oxygen.