Food preservatives can inhibit the growth and reproduction of microorganisms in foods, thereby prolonging food storage time, which is economical, efficient and convenient. You can find many kinds of chemical food preservatives on food packaging lables,such as sorbic acid, potassium sorbate, calcium sorbate, nisin, natamycin, dehydroacetic acid, nitrite, parabens, sodium diacetate, calcium propionate, sodium lactate etc. However, a large number of studies have shown that long-term intake of chemical food preservatives is not healthy.
For example, eating too much chemical preservatives such as sorbic acid will cause excessive consumption and loss of iodine, iron, calcium and other substances in the human body.Nitrate and nitrite added to foods, especially meat products, interfere with the secretion of thyroid hormones and thus affect the body's metabolic processes. Moreover, nitrate and nitrite may have connection with gastrointestinal cancer and nervous system cancer.If the beverage containing sodium benzoate is drank together with the beverage containing vitamin C, which can interact to form benzene. Benzene is a carcinogen and may pose a cancer risk.
A large number of studies have shown that many plant extracts have the characteristics of bactericidal and insecticidal, and can benefit human health, such as ginkgo biloba extract, pomegranate peel extract, cinnamon extract, clove extract, rosemary extract, red yeast extract, garlic extract, sweet pepper extract, pepper extract, green tea extract, cinnamon extract etc. Currently, the following plant extracts are popular with food preservative field:
Pomegranate skin contains a variety of alkaloids, pomegranate extract has a broad-spectrum antibacterial effect, and has obvious inhibitory effect on a variety of bacteria and fungi. By injecting pomegranate skin extract into the meat, the meat can be effectively protected from decaying and breeding bacteria.
Tea polyphenols are active ingredients extracted from green tea leaves.They can kill botulinum and spores and inhibit the activity of bacterial exotoxin, especially have obvious inhibitory effect on Staphylococcus aureus and mutant bacillus. Adding tea polyphenols to meat product can form a gas-impermeable hard film on the surface of the meat product, thereby inhibiting the oxidation and rancidity of the meat product and the growth of bacteria. In addition, tea polyphenols inhibit the oxidative rancidity of oil and fat, and are used in the field of edible animal and vegetable oil, fried food, and sea food.
The extract of garlic is allicin, which has the ability to activate cells, promote energy, and increase the antibacterial and antiviral properties. The strong killing effect it has on both Gram-positive and Gram-negative bacteria is standing and even stronger than the chemical preservatives benzoic acid and sorbic acid. No wonder it is the most antibacterial effect among the natural plants found so far.
Garlic extract is especially suitable for the preservation of fruits and vegetables, it can significantly make the flavor and color of the fruit better. While reduce the rate of decay, Garlic extract inhibit the loss of vitamin C content, thereby the fruit nutrients are retained to a large extent.
Cinnamaldehyde, Cinnamon extract, has strong bactericidal, antiseptic and anti-tumor effects. It can be used to improve fruit taste and brighten the color of the wine . It can also be used as an alternative to sodium benzoate and potassium sorbate for the preservation of tea drinks.
Undoubtedly, plant extract will play an increasingly important role in the field of food preservatives.