TECHNOLOGY OF CEREALS Composition of Maize Wet-Milled Products* Fibre Protein NDF+ h NFES Starch Corn gluten feed 22 0.1 low 62.0 2.5 Germ meal Steep liq 23.0 19.2 TNX6.Anon 1982;Wright, KN,1987. 5 Nitrogen-free extract modified starch, sweeteners and alcohol (Long, modified starch for particular purposes, or by 1982) enzymic hydrolysis, to yield maltose, which can Other uses for corn gluten include cork-binding be further treated to make dextrose(D-glucose) agent, additive for printing dyes, and in pharma- regular corn syrup, high-fructose corn syrup ceuticals. It is perhaps misleading that the protein (HFCS), and malto-dextrins product obtained from maize should be called In modifying starch, the objectives are to alter 'gluten,, because maize gluten in no way resembles the physical and chemical characteristics in order the vital gluten that is obtained from wheat(cf. to improve functional characteristics, by oxida tion, esterification, etherification, hydrolysis Ethanol can be made by yeast fermentation of or dextrinization. The methods used are acid naize starch, and has articular advantage thinning, bleaching or oxidation, cross-linking because the yeast can be re-cycled. About 85% substitution or derivatization, instantizing of the ethanol produced from maize starch is In acid thinning, or conversion, the glucosidic blended with gasoline, in which it acts as an linkages joining the anhydroglucose units are octane enhancer for unleaded fuel (May, 1987). broken, with the addition of water. The resulting An edible film has been made from maize starch thinning reduces the viscosity of the starch paste mylose obtained from high-amylose maize(cf. and allows such starches to be cooked at higher p. 99). Suggested uses for the film include the concentrations than the native starch. In a wet packing of gravies, sauces and coffee process of conversion, the starch is treated wit The starch obtained from the milling of waxy 1-3% of hydrochloric or sulphuric acids at about maize(cf. p. 99), called'amioca', consists largely 50oC, then neutralized and the starch filtered off of amylopectin. Amioca paste is non-gelling and Acid-thinned starches are used in confectionery has clear, fluid adhesive properties products, particularly starch jelly candies(Moore Heated and dried maize starch/water slurries et aL. 1984). Non-food uses include paper -sizing yield pregelatinized starch, known as 'instant calendering, coating applications(Sanford and starch, as it thickens upon addition of cold water. Baird, 1983; Bramel, 1986). In a dry process onversion, in which dry starch powder is roasted with limited moisture and a trace of hydrochloric Uses for wet-milled maize products acid, the main product is dextrins, used for Uses for maize starch include paper manufac- adhesives and other non-food pur ture, textiles, adhesives and packaged foods, and In bleaching, or oxidation, aqueous slurries as the starting material for further processing by of starch are treated with hydrogen peroxide chemical treatment, to make various kinds of peracetic acid, ammonium persulphate, sodium264 TECHNOLOGY OF CEREALS TABLE 12.1 Composition of Maize Wet-Milled Products* Fibre Moisture Proteint Fat Crude NDF* Ash NFES Starch (Oh) (%) (%) (Yo) (”1 (%) (Yo) (Oh) Maize 15.5 8.0 3.6 2.5 8.0 1.2 69.2 60.6 Corn gluten feed 9.0 22.6 2.3 7.9 25.4 7.8 50.1 low Corn meal 10.0 62.0 2.5 1.2 4.1 1.8 22.5 low Germ meal 10.0 22.6 1.9 9.5 41.6 3.8 52.2 low Steep liquor 50.0 23.0 0 0 0 7.3 19.2 low * Sources: Anon. 1982; Wright, K. N., 1987. t N X 6.25. $ Neutral detergent fibre. $ Nitrogen-free extract. modified starch, sweeteners and alcohol (Long, modified starch for particular purposes, or by 1982). enzymic hydrolysis, to yield maltose, which can Other uses for corn gluten include cork-binding be further treated to make dextrose (D-glucose), agent, additive for printing dyes, and in pharma- regular corn syrup, high-fructose corn syrup ceuticals. It is perhaps misleading that the protein (HFCS), and malto-dextrins. product obtained from maize should be called In modifying starch, the objectives are to alter ‘gluten’, because maize gluten in no way resembles the physical and chemical characteristics in order the vital gluten that is obtained from wheat (cf. to improve functional characteristics, by oxida￾p. 260) tion, esterification, etherification, hydrolysis Ethanol can be made by yeast fermentation of or dextrinization. The methods used are acid maize starch, and has a particular advantage thinning, bleaching or oxidation, cross-linking, because the yeast can be re-cycled. About 85% substitution or derivatization, instantizing. of the ethanol produced from maize starch is In acid thinning, or conversion, the glucosidic blended with gasoline, in which it acts as an linkages joining the anhydroglucose units are octane enhancer for unleaded fuel (May, 1987). broken, with the addition of water. The resulting An edible film has been made from maize starch thinning reduces the viscosity of the starch paste, amylose obtained from high-amylose maize (cf. and allows such starches to be cooked at higher p. 99). Suggested uses for the film include the concentrations than the native starch. In a wet packing of gravies, sauces and coffee. process of conversion, the starch is treated with The starch obtained from the milling of waxy 1-3% of hydrochloric or sulphuric acids at about maize (cf. p. 99), called ‘amioca’, consists largely 5OoC, then neutralized and the starch filtered off. of amylopectin. Amioca paste is non-gelling and Acid-thinned starches are used in confectionery has clear, fluid adhesive properties. products, particularly starch jelly candies (Moore Heated and dried maize starch/water slurries et al. , 1984). Non-food uses include paper-sizing, yield pregelatinized starch, known as ‘instant calendering, coating applications (Sanford and starch’, as it thickens upon addition of cold water. Baird, 1983; Bramel, 1986). In a dry process conversion, in which dry starch powder is roasted with limited moisture and a trace of hydrochloric acid, the main product is dextrins, used for Uses for wet-milled maize products Uses for maize starch include paper manufac- adhesives and other non-food purposes. ture, textiles, adhesives and packaged foods, and In bleaching, or oxidation, aqueous slurries as the starting material for further processing by of starch are treated with hydrogen peroxide, chemical treatment, to make various kinds of peracetic acid, ammonium persulphate , sodium