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Importance of starches for diversified industries can never be neglected. This biopolymer plays a vital role in food, nonfood and pharmaceutical industries. However, native starches require modification (both physical and chemical) to improve its functional traits. Physical modifications are nowadays preferable as these starches could be labelled as "Natural or Clean". Unmodified starches require heating to solubilize at room temperature. Whereas pregel starches overcome this limitation by dissolving at room temperature. Pregelatinized/cold water soluble/instant starches refer to the class of physically modified starches that hydrate, without heating providing instant viscosity and smooth texture when dissolved in cold water. Physical and chemical attributes could be achieved without affecting nutritional and organoleptic attributes. Different techniques like alcoholic-alkaline method, drum drying, extrusion and autoclaving are used for preparing pregels. Among all techniques, alcoholic-alkaline method has a higher edge over remaining methods adopted for preparing pregels due to superior thermal tolerance and enhanced viscosity. Instant starches/pregels impart unique functional characteristics that are desirable for various food products. These starches also preclude the heating step and could be dissolved at room temperature giving instant viscosity. These physically modified pregelatinized starches could be utilized in different food products as fat replacers, gluten substitute, coating agents, thickeners and as texture modifiers. This mini-review aims to give a brief overview of different methods used for preparation of pregels along with its properties and applications in food products. [ABSTRACT FROM AUTHOR]

Acetylated starches are a commercially important group of modified starch known for their reduced retrogradation tendency, high clarity, low viscosity, high swelling power, and lower gelatinization temperature and time. Due to these remarkable properties, acetylation is a commonly used chemical modification for preparing stabilized starches. This review summarizes the methods used for preparation of starch acetates and corresponding effects of acetylation on morphological, thermal, pasting, digestibility, textural, and other functional characteristics of starches isolated from various botanical sources. Starch acetates are also useful as packaging material, as wall material for encapsulating active ingredients, and to improve the storage stability of different products. [ABSTRACT FROM PUBLISHER]

Abstract: The effect of addition of three commonly used emulsifiers namely GMS (glycerol monostearate), SSL (sodium stearoyl lactylate) and DATEM (diacetyl tartaric acid esters of monoglycerides) on complexation, thermal, pasting and textural properties of OWSS (oxidized white sorghum starch) was studied. The study is of interest as both oxidized starches and emulsifiers are present as co-ingredients in different food products and thus their complexation could affect the textural characteristics of foods. The complexation index (CI) reduced on oxidation of sorghum starch. The CI for native white sorghum starch (NWSS) was in the order GMS > SSL > DATEM whereas for OWSS, CI was in the order GMS > SSL > DATEM. Presence of emulsifiers significantly reduced gelatinization enthalpies of starches. Types I and II amylose–lipid complexes were observed in NWSS and OWSS on addition of GMS. Pasting temperature of NWSS increased while peak viscosity reduced on addition of SSL and GMS. Cold paste and setback viscosities of OWSS increased significantly (p ≤ 0.05) on addition of emulsifiers. Emulsifiers reduced firmness and rupture strength of NWSS and OWSS gels. Increase in firmness of gels on storage increased in NWSS and decreased in OWSS on addition of emulsifiers. Elasticity of OWSS on cold storage was higher in the presence of SSL and GMS. [Copyright &y& Elsevier]

Gelatinization and retrogradation characteristics of native and modified white sorghum (Sorghum bicolor) starches were studied using differential scanning calorimetry. The biopolymer was modified through acetylation, oxidation, and acid thinning reactions to prepare single- and dual-modified white sorghum starches. The results revealed that peak gelatinization temperature (Tp) of AWSS (acetylated white sorghum starch) and AOWSS (acetylated-oxidized white sorghum starch) was less than that of NWSS (native white sorghum starch), while oxidation and acid thinning significantly increased the peak gelatinization temperature. Gelatinization enthalpy (ΔH) of ATWSS (acid-thinned white sorghum starch) was the least among both native and modified starches, which indicates weakening of starch granules after acid modification. Rate of retrogradation was lower in AWSS, OWSS, and AOWSS than NWSS, whereas acid thinning increased the rate of retrogradation. After 12 days of refrigerated storage at 4°C, percent retrogradation was in the order ATWSS > NWSS > AWSS∼AOWSS > OWSS. However, percent increment in retrogradation enthalpy was the least in AWSS. [ABSTRACT FROM AUTHOR]

The effects of different concentrations of guar and xanthan gums on functional properties of mango kernel starch (MKS) were studied. Both guar and xanthan gum enhanced the water absorption of MKS. The addition of xanthan gum appeared to reduce the SP (swelling power) and solubility at higher temperatures while guar gum significantly enhanced the SP as well as solubility of MKS. The addition of both gums produced a reinforcing effect on peak viscosity of MKS as compared to control. Pasting temperature of MKS was higher than that of starch modified by gums indicating ease of gelatinization. Guar gum played an accelerative effect on setback but xanthan gum delayed the setback phenomenon during the cooling of the starch paste. Both gums were found to be effective in reducing the syneresis while gel firmness was markedly improved. [ABSTRACT FROM AUTHOR]