1.1 Natural sources of carotene

Generally speaking, fruits or vegetables with stronger color in appearance are rich in natural β-carotene, such as carrot, spinach, celery, seaweed, gac fruit, wolfberry, broccoli and spirulina, etc. The molecular formula of carotene is C40H56, is a tetraterpenoid compound, this structure makes β-carotene have the effect of antioxidant, maintain human health, prevent body aging, diseases caused by tissue damage, cataract, cancer prevention, cardiovascular Diseases and other major medical problems have a positive impact. Carotene is easily soluble in organic solvents and extremely unstable when exposed to light, heat and oxygen. 

1.2 Extraction process of natural β-carotene

In the past ten years, there have been methods of extracting it from many different natural raw materials at home and abroad. Organic solvent extraction is the most traditional extraction method. According to the characteristics that carotene is easily soluble in ethyl acetate, acetone, n-hexane, petroleum ether and other solvents, the extraction time, temperature, solid-liquid ratio, and extraction times are adjusted to achieve The best economic benefits and the advantages of easy industrialization. 

Supercritical CO2 extraction technology has been widely used in the separation and extraction of various carotenoids. Maclas et al. extracted β-carotene from microalgae (Scenedesmusalmeriensis). The process conditions were as follows: extraction pressure 40MPa, extraction temperature 60°C, CO2: flow rate 1g/min, extraction 5h, yield of β-carotene 1.5 ms/g dry basis. The amount of β-carotene dissolved in CO2 is limited, so it is necessary to find a suitable entrainer, and the yield can be effectively improved after pretreatment. 

In addition, there are several new extraction methods such as ultrasonic-assisted extraction, microwave-assisted extraction, and enzymatic-assisted extraction.

(1) Ultrasonic-assisted extraction method is to use petroleum ether-acetone, methanol-acetone or tetrahydrofuran to repeatedly extract microalgae, and extract all-trans β-carotene under ultrasonic-assisted conditions.

(2) Microwave-assisted extraction is to use an appropriate solvent to extract microalgae . The extraction yield and extraction time are better than Soxhlet extraction, but this method has a microwave heating speed. This shortcoming may affect the structure and yield of the product.

(3) The enzymatic hydrolysis assisted extraction method uses pectinase cellulase to destroy cell walls and cell membranes, which can reduce the amount of organic solvents, save production time, and improve extraction efficiency, but it must be considered that the enzymes in organic solvents Activity limitation problem.

Natural β-carotene is the source of vitamin A, which can maintain normal visual health, protect cell health and improve immunity in the human body. Modern pharmacopoeia studies have shown that natural β-carotene can effectively reduce blood sugar in humans and animals. A study by Hangzhou University revealed the miraculous effect of carotene on rapidly reducing the level of nicotine in the blood of smokers. And as an antioxidant: taking a proper amount of β-carotene has the ability to prevent and alleviate immunity, anti-cancer, anti-cardiovascular and cerebrovascular diseases, and eye diseases.

Nowadays, health care products and health foods containing β-carotene as functional ingredients emerge in an endless stream on the market. The product forms are mainly in the form of tablets and capsules, and there are also products of oral liquid and nutrient solution. Because β-carotene The efficacy of β-carotene has great potential advantages. Many domestic scholars and fields have carried out a series of research and product development on it. The annual demand for β-carotene in the world continues to grow, the market continues to expand, and it is widely used in food. , medicine, aquaculture and other industries.

3.1 Microencapsulation Technology Products

Microencapsulation technology uses film-forming materials such as gelatin, gum arabic, sucrose, trehalose, etc., through physical methods (spray drying method, extrusion method, solvent evaporation method), chemical methods (interfacial polymerization method, in-situ polymerization method, etc.) , Physical and chemical methods (oil phase separation method, water phase separation method, drying bath method, etc.) to make microcapsules, according to environmental factors, the nature of carotene, determine the appropriate permeability, viscosity, solubility. This technology can effectively reduce the influence of light, heat, acid, alkali and oxygen on carotene, maintain the chemical properties of the core material, cover up uncomfortable odors, and extend the shelf life of products.

3.2 Carotene Soft Capsules

Soft capsule products are products that protect β-carotene from external adverse factors by using oils and fats, and are easy to absorb by the human body, such as NATURESBOUNTY β-carotene soft capsules in the United States and Amway Nutrilite natural carotenoid capsules on the market. etc. It can improve night blindness and dry eye disease, promote the activation of immune cells, and enhance immunity.

3.3 β-carotene tablets

Add β-carotene as the main ingredient to make tablets, chewable tablets and other forms. The natural carotene tablets produced by Yipinkang Health Food Co., Ltd. in the United States can improve eye fatigue, restore skin elasticity, prevent cardiovascular diseases, and improve immunity. force function.