The color and flavor of meat products are crucial sensory indicators used to assess food quality, and they play a significant role in consumer perception. Color is a visual stimulus, aroma is an olfactory one, and taste is a gustatory experience. While people often refer to "flavor" as the combination of smell and taste, scientifically speaking, these are distinct sensory experiences. Aroma specifically refers to the scent, while taste relates to the basic sensations detected by the tongue.
The processing of meat involves complex physical, chemical, and biological changes that affect its texture, color, and flavor. These transformations not only enhance digestibility but also influence the sensory attributes that consumers value. Therefore, maintaining and enhancing the color and flavor of meat products is a key skill for professionals in the meat industry.
1. **Color of Meat Products**
The color of meat varies depending on the animal species and the time since slaughter. This variation is largely due to the presence and transformation of myoglobin and hemoglobin. If bloodletting is incomplete during slaughter, more hemoglobin remains in the meat, leading to a darker appearance. Conversely, proper bleeding results in a lighter color. Myoglobin content also affects color—higher levels result in a redder hue. For example, beef and horse meat have higher myoglobin content than pork, while rabbit meat has less. Additionally, muscle activity influences myoglobin levels; muscles used more frequently, like those in the shoulders or legs, contain more myoglobin and thus appear darker. As animals age, their myoglobin content increases, deepening the meat's color. Diet and breed also influence this pigment.
During storage, myoglobin undergoes oxidation, changing the meat’s color. Initially purple, it turns bright red when exposed to oxygen, then becomes brown as it continues to oxidize. In rare cases, further oxidation can lead to a greenish tinge due to the formation of oxidized porphyrins. However, this typically occurs only under bacterial growth conditions, not with fresh meat. Most commonly, meat contains a mix of different forms of myoglobin, which together determine its overall color.
When meat is heated, the color changes significantly. At 65°C, raw red meat turns pink, and at 75°C, it becomes gray. This is due to the denaturation of myoglobin. High-temperature cooking can also trigger the Maillard reaction, contributing to browning and flavor development.
To maintain an attractive color, meat processors often use coloring agents such as nitrates, nitrites, and ascorbic acid. These compounds help stabilize the red color of cooked meat. Additionally, natural and artificial pigments are used. Natural options include chlorophyll, carotenoids, and beetroot extract, while synthetic ones like amaranth and sunset yellow offer vibrant colors but require strict regulation due to potential health concerns.
2. **Aroma of Meat Products**
The aroma of meat comes from both the raw material and the cooking process. Raw meat has a distinct scent influenced by fat composition and animal species. Research shows that volatile compounds in meat vary between beef, pork, and lamb. Factors like sex, diet, and pre-slaughter conditions also affect the smell. Cooking enhances the aroma through the breakdown of proteins and fats, producing complex flavors via reactions like the Maillard reaction and lipid oxidation.
3. **Taste of Meat Products**
Taste is a multifaceted experience involving psychological, physical, and chemical components. It includes the emotional response to food, the texture in the mouth (such as firmness or viscosity), and the chemical stimulation of taste buds (like salty, sweet, sour, bitter, and umami). The taste of raw meat is influenced by its juices, which contain amino acids and other compounds. When cooked, the flavor intensifies initially but may diminish over time due to the breakdown of proteins and sugars.
To enhance taste, meat products often include flavor enhancers like glutamates, sweeteners, and spices. These ingredients improve palatability and mask undesirable odors, making the final product more appealing to consumers.
DIYAS development Limited , https://www.diyastea.com