Alfalfa is a perennial leguminous herb, which has a long history and wide distribution in China. It has the advantages of high yield, strong stress resistance, rich in many active substances, and has important development value. Ultrasonic extraction technology utilizes cavitation, mechanical and thermal effects to accelerate intracellular material release and improve extraction efficiency. In the field of food research, different frequencies of ultrasound have different uses, and low-frequency ultrasound can be used in a variety of food processing processes to improve food quality.
The optimal extraction conditions were determined by ultrasonic-assisted ethanol acidification and orthogonal experiment. The anthocyanins obtained under this condition had strong acid resistance and heat resistance, and some food additives and metal ions would affect its stability.
Ultrasound assisted extraction of alfalfa polysaccharide was optimized to obtain higher content of polysaccharide. The purified polysaccharide has typical polysaccharide characteristics and good antioxidant activity, and can be used to develop functional food. Alfalfa polyphenols with good antioxidant activity can be obtained by ultrasonic extraction under specific conditions. A variety of ultrasonic-assisted extraction methods could effectively improve the extraction efficiency of total flavonoids from alfalfa. The optimal extraction conditions were determined by different experiments, and total flavonoids had good antioxidant capacity.
Ultrasonic-assisted extraction of alfalfa leaf protein under alkaline conditions can increase extraction rate and shorten extraction time.
Alfalfa, with luxuriant foliage and developed roots, can effectively preserve soil and water, and has strong adaptability and regeneration ability. Alfalfa is rich in color and can be used for garden cover, slope greening and soil improvement.
Response surface analysis method has advantages in optimizing the extraction conditions of active substances in alfalfa. Alfalfa has comprehensive nutrition, and ultrasonic assisted extraction can enhance its development value. With the deepening of research, alfalfa active substances have broad application prospects in food, health and environment.
