Development of Biodegradable Products from Modified Starches

LEANDRO LUDUEÑA; VERA A. ALVAREZ; MARÍA PAULA GUARÁS

Starch-based Materials in Food Packaging: Processing, Characterization and Applications

Elsevier

Año: 2017; p. 77 - 123

Native starches, regardless of their source, do not have much applicability dueto its low tolerance to processing conditions. The general disadvantages arelow paste clarity, lack of free-flowing properties, hydrophilic character of thegranules, insolubility or failure to swell in cold water, excess viscosity, pHsensitivity, heat and shear, high retrogradation, and syneresis (Singh, Singh,Ezekiel, & Kaur, 2011). These drawbacks make crucial to enhance desirablefunctional properties; in order to overcome them, modification of starches byphysical, chemical, and enzymatic processes can be employed (Afolabi, Olu-Owolabi, Adebowale, Lawal, & Akintayo, 2012). One of the main drawbacks of thermoplastic starch (TPS) is poor water resistance, which limits its application. To overcome this drawback, an effective method is chemical modification including esterification, etherization or oxidation (Aburto et al., 1999; Fang, Fowler, Tomkinson, & Hill, 2002; Fringant, Rinaudo, Foray, & Bardet, 1998; Parandoosh & Hudson, 1993; Sagar & Merrill, 1995; Wesslén & Wesslén, 2002; Wing & Willett, 1997), among others. Chemical modification can involve the introduction of functional groups into the starch molecule, such as through oxidation, etherification, esterification, crosslinking, dual modification among others, thus improving the applicability of plant-derived materials in food and nonfood industries (Bertolini, 2010b; Nafchi, Tabatabaei, Pashania, Rajabi, & Karim, 2013; Xia, Hu & Marquez, 2005). Starches can also be physically modified by moist heat treatment and annealing. (Adebowale,Henle, Schwarzenbolz, & Doert, 2009; Hoover, Hughes, Chung, & Liu, 2010;López, Zaritzky & García, 2010)