Extraction of pigments in vegetables

The color of food is an important sensory index of food. In the food industry, artificially synthesized pigments are widely used to increase the color. However, studies have shown that the commonly synthesized pigments have different degrees of toxicity, and some are even carcinogenic. Therefore, the development of natural and harmless food pigments is of great significance for ensuring human health. There are many kinds of vegetables and colorful colors. It is a huge resource pool for pigments. The natural edible pigments extracted from vegetables not only have high safety, but also have certain nutritional value and health care effects. In addition, natural pigments are expensive and have a promising market. They can promote the appreciation of vegetables and are a development direction for deep processing of vegetables. This article will introduce pigments in several vegetables and their extraction methods.
First, extract lycopene from tomatoes 1. The properties and functions of lycopene Lycopene is an oil-soluble pigment that is sensitive to light, oxygen and heat. It is a kind of carotenoid and it is also a strong antioxidant. Its antioxidant capacity is vitamin E. More than 100 times, far more than others. The biological activity of carotene and β-carotene can effectively eliminate free radicals in the body, prevent and repair cell damage, and inhibit the oxidation of DNA to prevent the occurrence of cancer. At present, lycopene is used as a pigment in small quantities in tomato sauce and tomato juice products, and is mostly used in health food and pharmaceutical industries.
2. Extraction of lycopene Extraction of lycopene is generally divided into organic solvent extraction and carbon dioxide supercritical extraction. Carbon dioxide supercritical extraction is difficult in large-scale production. Currently, organic solvent extraction is mainly used to process tomato into tomato first. The sauce or tomato powder is extracted with a solvent such as ethyl acetate, ethanol or n-hexane, and then filtered and concentrated to obtain a lycopene crude product—an oleoresin content of less than 6%. Further freeze crystallization can result in higher purity. product.
Second, extract capsanthin from pepper 1. The properties of capsanthin Capsanthin is also known as capsanthin, capsanthin, and pure capsanthin is a deep, fat red needle-like crystal. The capsanthin used in food additives, etc. is a dark red ointment with a spicy taste. Its main components are capsanthin, carotenoids, capsaicin, vegetable oil, etc. It is insoluble in water and easily soluble in vegetable oils and ethanol. At pH values ​​of 3--12, the hue does not change, and the light resistance and heat resistance are comparable. Good, acid and alkali resistant, resistant to oxidation, can be used for tins, cakes, coloring, can also be used for fat foods, spices, juices and ice cream.
2. Extraction of capsanthin Common methods for extracting capsanthin can be roughly divided into three methods of oil dissolution, solvent and supercritical fluid extraction. In the current production, the solvent method is mainly used to extract the fruits of the genus Capsicum with organic solvents (dichloromethane, trichloroethylene, acetone, 2-propanol, methanol, n-hexane, and ethanol), and then remove the oil-soluble products of organic solvents. Lactose, gum arabic and other excipients and sucrose fatty acid esters can be made into water-dispersed products.