Glycine is the smallest of the amino acids. It is ambivalent, meaning that it can be inside or outside of the protein molecule. In aqueous solution at or near neutral pH, glycine will exist predominantly as the zwitterion
The isoelectric point or isoelectric pH of glycine will be centered between the pKas of the two ionizable groups, the amino group and the carboxylic acid group.
In estimating the pKa of a functional group, it is important to consider the molecule as a whole. For example, glycine is a derivative of acetic acid, and the pKa of acetic acid is well known. Alternatively, glycine could be considered a derivative of aminoethane.
1. Glycine powder is used as a flavoring, sweetener and nutritional supplement.
2. Glycine powder is applied in alcoholic beverage, animal and plant food processing;
3. Glycine powder is applied in the making of salted vegetables and sweet jams;
4. Glycine powder is also as an additive for the making of salted sauce, vinegar and fruit juice, in order to improve the flavor and the taste of food and increase the nutrition of food;
5. Glycine powder is used as a preservative for fish flakes and peanut jams and stabilizer for cream, cheese etc.
6. Glycine powder is used as a buffering agent for the taste of edible salt and vinegar.