Optimization of mucilage extraction conditions from (Althaea officinalis) using microwaves and by the response surface methodology

Althaea officinalis is one of the plants containing mucilage, the therapeutic effect of its mucilage on the mucous membrane of the tissue and the healing of stomach ulcers has been proven. The mucilage of this plant consists of L-rhamnose, D-galactose, galacononic acid and D-glucuronic acid. The polysaccharides found in this plant have antioxidant properties. The main antioxidant activity of this plant is related to its α-tocopherol composition. Gums extracted from different sources have different functional and rheological properties than each other, and the conditions of extraction have a significant effect on these properties. In this research, the extraction efficiency of Althaea officinalis mucilage as a new hydrocolloid source was studied. For this purpose, the effect of microwave power (250-850W), water-grain ratio (50-90) and time (2-10 minutes) on the extraction efficiency were optimized. The gum extraction efficiency ranged from 4.4% to 11.6%. It can be seen that the lowest amount of extraction was obtained at a ratio of water to grain of 70, time of 2 minutes and power of 550 watts, and the maximum amount of extraction was obtained at a ratio of water to grain of 80, time of 4 minutes and microwave power of 700 watts. According to the results obtained from analysis of variance Data, quadratic model is the best model to describe data. In low powers, increasing the ratio of water to seeds led to an increase in extraction efficiency. The increase in extraction efficiency by increasing the ratio of water to seeds can be attributed to the presence of more solvent, which intensifies the driving force for the transfer of gum mass from the seeds.