How is monosodium glutamate refined

The initial industrial production of monosodium glutamate in China is to produce monosodium glutamate with gluten or soybean meal as raw materials by acid hydrolysis. This method is characterized by high energy consumption, high cost, high labor intensity and high requirements for equipment, which requires acid and alkali resistant equipment. 1965 were all produced in this way before. With the development of society, it withdrew from the historical stage.

The methods of extracting glutamic acid include isoelectric point method, ion exchange method, metal salt method, hydrochloric acid hydrolysis-isoelectric point method, ion exchange membrane electrodialysis method and so on. After extraction, sodium glutamate was refined to meet international standards. The finished product is colorless or white columnar crystalline powder. Soluble in water, slightly soluble in alcohol, stable to light and heat. There is a strong meat flavor, which can still be tasted when diluted 3000 times.

Combined with salt, it can enhance its umami flavor, and the best flavor effect is to add 0. 1-0. 15g sodium glutamate to 1g salt. When combined with inosine and guanylic acid, the umami taste can be improved by 4-6 times. Mixing the above materials to make strong monosodium glutamate. Suitable for family, catering industry and food processing industry, the general dosage is 0. 1-0.5%.

Extended data:

The sensory threshold of sodium glutamate on human tongue taste receptors is low, which is 0.03% at room temperature. Although the main component of ordinary monosodium glutamate is sodium glutamate, it is not pure umami taste, but has five flavors: sour, sweet, salty, bitter and fresh, and umami taste accounts for a large proportion (the proportions of five different flavors are umami taste 7 1.4 1%, salty 13.50% and acid 3.4).

At the same time, the umami taste of sodium glutamate can only be presented in the presence of salt, which has a certain inhibitory effect on sour taste and bitter taste, that is, it has a certain degree of taste buffering effect. If you add pure monosodium glutamate to the dishes without salt, it will not only have no umami flavor, but will make people have an unpleasant smell.

References:

Baidu encyclopedia-monosodium glutamate