Sodium glycinate is the sodium salt of glycine (non-essential α-amino acid).

Amino acids play a key metabolic function in the human body and are constituents of proteins.

As food additives they perform different functions: preservatives, flavour enhancers, food supplements and more.

Amino acids together with their salts are used in cosmetics as conditioning agents for both hair and skin (e.g. as moisturisers and other similar functions). Moisturisers are different in nature: the best are the natural ones that exploit the mechanism of integration between the ingredient and the skin by moisturising the horny hydrolipid film, i.e. the thin protective layer that lines the epidermis, protecting it from harmful external microbes, keeping the skin moisturised and supple and its pH or acidity value between 4 and 6. Then there are the occlusive moisturisers, usually derived from petroleum (Paraffinum, Paraffinum liquidum and others), but also triglycerides, lanolin oil, natural or synthetic waxes, fatty acid esters and others that create an artificial occlusive layer on the stratum corneum of the skin with the advantage of accelerating the protective process but with the disadvantage of preventing the skin's natural transpiration.

α-amino acids that have similar physical structures undergo similar changes with regard to solubility in water/ethanol mixtures, and technologies to separate α-amino acids from industrial residues, which may not even be innocuous, are constantly being improved. However, many data on the solubility in water-ethanol and ethanol of some α-amino acids are contradictory or even lacking, and the effects of ethanol on the solubility of amino acids may be different. Overall, the scientific literature considers that α-amino acids do not pose significant problems for human health when taken orally, except in people with certain genetic diseases.

Food

Ingredient listed in the European food additives list as E640, a flavour enhancer to improve the taste of food and drink.

Food safety: α amino acid generally considered safe.

Cosmetics

Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

Cosmetic safety: α-amino acid generally considered safe when formulated to be non-irritating.

• Molecular Formula   C₂H₄NNaO₂ 
• Molecular Weight     97.05
• CAS  6000-44-8
• UNII    F6B979BV8Z
• EC Number 227-842-3

References_____________________________________________________________________

Baghban, A., Zilabi, S., Golrokhifar, S. and Habibzadeh, S., 2018. Neural computations in modelling of CO2 capture from Gas stream emissions by Sodium Glycinate solution. Petroleum Science and Technology, 36(4), pp.326-331.

Ghosh, S., Ray, G.B. and Mondal, S., 2015. Physicochemical investigation on the bulk and surface properties of the binary mixtures of N-methyl-N-dodecanoyl sodium glycinate (SDDS) and N-methyl-N-decanoyl glucamine (MEGA 10) in aqueous medium. Fluid Phase Equilibria, 405, pp.46-54.

ЖИРІВ, М., 2021. Sodium glycinate as a neutralizing agent in technologies of refining modified fats. Deutsche internationale Zeitschrift für zeitgenössische Wissenschaft ٠٠٠ № 8 2021 VOL., p.40.

Rahn, A.K. and Yaylayan, V.A., 2015. Mechanism of chemical activation of sodium chloride in the presence of amino acids. Food chemistry, 166, pp.301-308.

Lee, D.S., 2016. Carbon dioxide absorbers for food packaging applications. Trends in Food Science & Technology, 57, pp.146-155.