Consumer satisfaction is an important requirement for the commercialization of meat products. With the increase of human welfare and living standards, people prefer better tasting meat with a nutritionally healthy composition. As a result, attention increases to improve the carcass traits and the meat quality in poultry, pork, beef and other meat production.
Influence of nutrition
Nutritional strategies have not only an impact on carcass composition such as fat and lean meat contents. Also, the sensory quality and the nutritional composition of the meat can be influenced by the feed. A specific example of such a nutritional strategy is the increase of dietary betaine levels by supplementing feed with betaine additives.
Dietary betaine supplementation is possible with either anhydrous betaine sources (available from natural or synthetic origin) or betaine hydrochloride. All these betaine additives are efficacious in providing available betaine for absorption. The availability of dietary betaine will subsequently influence multiple physiological processes.
Betaine is a naturally occurring compound in animals, with a vitamin-like nutritional function. In the liver, it is mainly involved in methyl group transition. In other cells it functions as an osmoprotectant: a protective regulator of the cellular osmotic pressure and water balance. The molecular structure of betaine is a derivative of the amino acid glycine, and consequently, betaine also has a role in protein metabolism. Moreover, the biological function of betaine has
an impact on lipid and energy metabolism.
It was already observed decades ago that betaine additives can alter fat distribution in the body of animals and thus influence carcass composition. Therefore, betaine is often referred to as a ‘carcass modifier’. Recently, more and more studies in different animal species show that meat quality is influenced as well and suggest betaine can also be considered as a ‘meat quality modifier’.
Betaine and meat quality
Meat quality is generally measured by two factors: the nutrients indexes and the sensory quality. Protein is the first and most important nutritious component of meat. The composition and content of proteinogen ic amino acids shape the nutritional value and flavor of the meat. Secondly, levels of fat and concentrations
of different fatty acids are also of importance for both the nutritional and sensory value of animal products.
Studies on the effect of betaine on nutrients indexes are limited, however the influence of betaine can be recognized due to its role in both protein and fat metabolism. It is described that betaine reduced saturated fatty acids (SFA) and enhanced poly-unsaturated fatty acids (PUFA) contents in poultry (Yang et al.,
2022), lamb (Dong et al., 2020) and pigs (Zhong et al., 2021). In this last study, also a slightly altered free amino acid profile in serum and muscle was observed.
Regarding sensory quality of meat, there are several important parameters: Drip loss/Water loss, water holding capacity (WHC), cooking loss, shear force, pH, and meat color measurements including L*(lightness), a* (redness) and b* (yellowness) values.