Introduction

One of the biggest challenges for the meat industry is keeping its products on display on the shelves, since these foods undergo oxidative action as soon as they come into contact with air. Oxygen is the great “enemy”, its action causes loss of quality, especially with regard to color, which is considered the most important sensory characteristic. Fresh meat has a very intense shade of red, which adds value to it. Over time, meat changes from a bright red to brown tones, which depreciates it in the eyes of consumers. Consumers quickly identify old meat, paying no attention to it when buying it.

Have you ever wondered what causes the change in the visual appearance of meat?

First, we need to understand why meat has this intense red color. As we know, meat is mainly composed of muscles, which in turn are formed by fibers. Well, in fibers we find a protein called myoglobin, which is naturally reddish. The main function of this protein is to store oxygen in the muscles to be used in the metabolic activities of the cells, in what is known as cellular respiration. This is a process present in organic cells, with the aim of oxidizing them and producing energy that will be used to generate muscle strength. Myoglobin levels determine how red the meat will be. Animals that move constantly also have high concentrations of the protein, as is the case with cows.

When exposing meat to air, myoglobin is oxidized by the action of oxygen, transforming into a pigment called oxymyoglobin. It is formed between 30 and 40 minutes of exposure of the meat to air. However, this oxidation reaction can be reversible due to factors such as temperature, microbial load, low pH, increased ultraviolet light and also due to low oxygen tension. This reversion will generate myoglobin again, but another substance also appears, which is metmyoglobin, which does not have an intense red color like the first ones, in fact it has a brown color, which is quite undesirable for the product. The reversal reaction occurs within a few minutes. According to MacDougall (1994), only 20% of the meat area being occupied by metmyoglobin is enough to provoke disdain among consumers.

Industry Tactics

The market implements some actions aimed at not compromising the quality of meat color, such as: avoiding machine processing using only knives, freezing and the use of preservatives. Processing using equipment such as grinders and saws increases the area of contact with air. Therefore, the use of knives reduces the exposure area. Cooling meat to freezing point reduces the speed of discoloration because some enzymes start to use oxygen, removed from myoglobin. The use of preservatives in meat products mainly seeks to fix the color, prevent oxidation and perform microbial control. Examples of preservatives most used today: nitrites, nitrates, sodium erythorbate and vitamin C.

And how does Acerola fit into this story?

Acerola is known as one of the greatest natural sources of vitamin C among all foods. It can reach incredible levels of vitamin C, reaching up to 4,500 mg/100 g in green fruits, while the market’s favorite source does not reach 3% of the acerola’s content.

“The fruit contains an exorbitant amount of ascorbic acid in the range of 1500–4500 mg/100 g, which is equivalent to about 50–100 times more than orange or lemon. Having a phytonutrient content, the fruit exhibits high antioxidant capacity and several interesting biofunctional properties, such as skin lightening effect, anti-aging action and multidrug resistance reversal activity” (Prakash & Baskaran, 2018, p. 1).”

Due to its antioxidant capacity, acerola has been used as a food preservative, including in meat preservation. The vitamin C present in acerola acts as an antioxidant that prevents the oxidation of myoglobin into metmyoglobin. By reducing these oxidized molecules, the vitamin C in acerola keeps meat intensely red for much longer. Using acerola also has other advantages over using other preservatives. It is known that nitrites and nitrates used in excess can cause the formation of nitrosamines, which are substances that are harmful to the human body. In relation to sodium erythorbate, acerola has the advantage of being a natural product, which pleases all consumers. It is also cheaper than erythorbate.

Conclusion

Keeping meats with their bright red appearance is a huge challenge for the market. Ensuring this quality increases consumer acceptance. Acerola emerged in this context, bringing with it its calling card a high content of vitamin C, its antioxidant power and a pool of phytonutrients. Its use is not associated with risks due to excessive consumption, which is common in the consumption of synthetic products. It also stands out for being a natural product, in line with market trends, which seek healthy and sustainable products.

References

MACDOUGALL, D.B., Colour meat – its basis and importance. In Pearson, A.M. & DUTSON. T.R. (ed) – Quality attributes and their measurement in meat, poultry and fish product – Advances in meat research series, vol.9, Black Academic & Professional, cap.2, p. 34–78, 1994.

SANTOS, Vanessa Sardinha dos. “Cellular respiration”; Brasil Escola. Available at: https://brasilescola.uol.com.br/biologia/respiracao-celular.htm. Accessed on January 16, 2025.

Prakash, A & Baskaran, R. Acerola, an untapped functional superfruit: a review on latest frontiers, 2018.