Solvents for Zein. Primary Solvents

Abstract

Primary organic solvents for zein are either hydroxy compounds, amines, amides, or acids. The stability of zein in single solvents is, in general, much better than in binary solvents containing water.Twenty per cent solutions of zein in diethylene glycol, triethylene glycol, propylene glycol, and dipropylene glycol have remained clear and fluid for two years when stored at 27°C ., while a similar concentration of zein in 85 per cent aqueous ethyl alcohol stored at the same temperature usually gels in about 30 days.

REVIEW: Zein Extraction from Corn, Corn Products, and Coproducts and Modifications for Various Applications: A Review

“…The extracted zein solution and gluten were separated and the zein solution cooled to 15°C and filtered. Evans and Manley (1941, 1943). The hexane could be removed and the zein precipitated in water.…”

“…The CGM was then washed with water and extracted with 80% ethanol. Solvents with Evans and Manley (1941, 1943. Water precipitated the zein, which was dried for pharmaceutical use.…”

“…There are three different types of solvents for extracting zein: primary solvents, secondary solvents, and ternary solvents Manley 1941, 1944;Manley and Evans 1943) (Table III). A primary solvent is a compound that could dissolve zein alone in a concentration >10% (Evans and Manley 1941). To stand alone as a solvent for zein, it needs to be able to interact with the amino acids of zein so that it could simultaneously dissolve both the polar and nonpolar amino acids in zein.…”

Zein-Polyaniline Blends—a Route to Electrically Conductive Biopolymer

“…diethylamine, ethylenediamine. On the contrary, many solvents for zein were mentioned [15][16][17], but NMP has never been reported among them, according to our knowledge. We have been found it as a good solvent for zein as well, which allows to get upto 10% concentration at room temperature and to be used as a common solvent for both PANI and zein.…”

Determinants for yield and quality of zein extracted from corn gluten meal

“…The protein can be dissolved in a dilute aqueous alkali solution within a pH range of 11.3-12.7 or in a strong acidic solution (12 N HCI) . Zein is also soluble in many organic solvents containing hydroxyl, carboxyl, and amino moieties in the proper ratio of polar and non-polar groups (Evans and Menley 1941;Menley and Evans 1943). Aqueous ethyl and isopropyl alcohol are the most common solvents for zein.…”