Solvent Extraction of Zein from Dry‐Milled Corn

Abstract

Batch extraction of zein from dry‐milled whole corn with ethanol was optimum with 70% ethanol in water, an extraction time of 30–40 min, and temperature of 50°C. High yields (60% of the zein in corn) and high zein contents in the extracted solids (50%) were obtained at a solvent‐to‐solids ratio of 8 mL of 70% ethanol/g of corn. However, zein concentration in the extract was higher at lower ratios. Multiple extraction of the same corn with fresh ethanol resulted in a yield of 85% after four extractions, whereas multiple extractions of fresh corn with the same ethanol resulted in high (15 g/L) zein concentration in the extract. Optimum conditions for batch extraction of zein were 45°C, with 68% ethanol at a solvent‐to‐solids ratio of 7.8 mL/g for an extraction time of 55 min. Column extractions were also best at 50°C and 70% ethanol; a solvent ratio of 1 mL/g resulted in high zein concentrations in the extract (17 g/L) but yields were low (20%).

Propriedades mecânicas e molhabilidade de filmes de zeínas extraídas de glúten de milho

“…A maioria desses processos tem por base o uso de soluções alcoólicas, de baixa polaridade, empregadas como solventes. Segundo determinações de Shukla et al [16] , as maiores eficiências de extração de zeínas foram obtidas fazendo uso de etanol concentrado como solvente, considerando que a fração solúvel em álcool constitui na maior parte (80-90%) das proteínas presentes no milho, e a restante fracamente solúvel em álcali [17] . Adotamos neste trabalho a sequencia de extração desenvolvida por Forato [18] a partir do glúten de milho, processo esse em corrente uso na unidade da Embrapa Instrumentação.…”

Effect of plasticizing sugars on rheological and thermal properties of zein resins and mechanical properties of zein films

“…CGM has low price and is used mainly for animal feeding (Dickey & Parris, 2001;Landry, 1997). However zein is an expensive product and thus extraction of zein and production of biodegradable film from it, would produce important economic benefits (Landry, Drihaye, & Damerval, 2002;Shukla, Cheryan, & Devor, 2000). Zein has excellent film forming properties and can be used for fabrication of biodegradable films.…”

Recombinant human proinsulin from transgenic corn endosperm: solvent screening and extraction studies

“…However, the temperature should not be increased indefinitely since higher temperatures cause protein denaturation. Shukla et al (2000) also studied the effect of temperature on the extraction of proteins (zeins) from corn. They found that zein solubilization in the range of 20 to 60°C was highest at 50°C.…”