It’s not only how your steak was cooked, but also how the animal was raised, what it was fed and how it was handled before it became that tasty morsel on your plate.

Juiciness, tenderness, flavor, color and consistency are the main characteristics that determine a consumer’s acceptance or rejection of fresh meat.

Meat quality is influenced by a variety of factors such as animal heredity, dietary program, nutritional status, pre-slaughter and slaughter conditions, and meat processing conditions.

Animal and meat scientists are working together to find solutions to quality issues hindering the meat industry. One primary concern is quality deterioration during retail and home storage due to lipid and protein oxidation, which produces rancid off-odors and off-flavors, and decreases juiciness and tenderness.

Compared to white meat, red meat contains a larger amount of lipids and iron-containing compounds, which can act as a catalyst for lipid and protein oxidation, leading to quality deterioration.

One approach to reduce oxidation and related problems is to feed animals diets enriched with antioxidants. Enhancing diets with antioxidants and optimizing nutrient intake could aid in overall animal health and could reduce oxidative processes, thereby improving textural traits of meat.

Vitamin E

Vitamin E, also known as α-tocopherol, is perhaps the best-researched dietary antioxidant. It is an essential nutrient for the growth and health of animals by functioning as an antioxidant in various biological systems.

Incorporating vitamin E into the feed of cattle has been reported to improve color stability. Despite the “sell by” date, freshness is evaluated by consumers visually.

Consumers often associate the cherry red color of fresh red meat as an indicator of a high-quality, nutritious and wholesome product. Discoloration during retail display limits product shelf life and increases economic losses due to price reduction and shrink.

Previous studies have found that incorporating vitamin E into the diet of cattle can help maintain the cherry red color during display for up to one day longer.

Not only has incorporation of dietary vitamin E been reported to improve color stability, but it can also reduce lipid oxidation. Vitamin E prevents free radicals from reacting with other biological compounds such as proteins and lipids, ultimately protecting meat from oxidative damage.

Selenium

Selenium is another well-researched antioxidant mineral. It is an essential trace micronutrient for both humans and animals.

Selenium is a key component of certain enzymes, such as glutathione peroxidase, which has strong antioxidant properties and can work synergistically with vitamin E. Glutathione peroxidase protects cells from toxic radicals and peroxides, thereby preventing oxidative damage to the body.

In humans, adequate intake of Se may decrease the risk of cancer, cardiovascular disease and other immunodeficiencies. Furthermore, studies have shown an increase in glutathione peroxidase activity in tissues of cattle, pigs and poultry when fed a diet supplemented with selenium.

Dietary supplementation of organic selenium in cattle has been shown to increase glutathione peroxidase activity and improve oxidative stability of fresh meat during storage.

Antioxidants

Similar results have been shown on the poultry side as antioxidant supplementation with algae-based selenium yeast and organic minerals provide a protective barrier against oxidation throughout storage in chicken breast meat.

The protective effect provided by the antioxidant supplementation is due to an increase in antioxidative enzyme activity in the tissue of chicken breast meat.

Antioxidant enzymes aided in the removal of reactive species and inhibited oxidative reactions, resulting in improved yields throughout refrigerated storage and cooking, and a more tender chicken breast. Further studies are under way to determine if the same effects can be demonstrated in beef.

Antioxidants can potentially promote meat tenderness as well. Tenderness and associated juiciness (water-holding capacity) are important quality parameters.

Increased tenderness is attributed to postmortem breakdown of key skeletal proteins, which is mediated by the calpain enzyme system. Variations in muscle tenderness may be attributed to the activity rate of calpastatin, an enzyme that inhibits calpain.

Studies have shown that calpain is remarkably susceptible to oxidation.

When oxidized, calpain is inactivated, resulting in a reduced tenderness and decreased water-holding capacity of postmortem beef muscle.

Although it is not clear whether dietary antioxidants could protect calpain from oxidation, normal protein breakdown during storage would be ensured if the antioxidants do indeed provide protection, leading to desirable tenderness.

Assuming dietary antioxidants could promote protein degradation, the meat flavor would improve as well because products of protein breakdown (short peptides, amino acids) impart savory tastes.

Although more work is needed to fully understand the interaction between diet, oxidative stability and meat quality, we are slowly uncovering the mystery of meat. In the meantime, it appears that the saying is true. You are what you eat. 

References omitted due to space but are available upon request. Click here to email an editor.