Impact of acid and oxidative modifications, single or dual, of sorghum starch on biodegradable films

Abstract

The objective of this study was to evaluate the effects of acid and oxidation modifications on sorghum starch, as well as the effect of dual modification of starch on the physical, morphological, mechanical, and barrier properties of biodegradable films. The acid modification was performed with 3% lactic acid and the oxidation was performed with 1.5% active chlorine. For dual modification, the acid modification was performed first, followed by oxidation under the same conditions as above. Both films of the oxidized starches, single and dual, had increased stiffness, providing a higher tensile strength and lower elongation when compared to films based on native and single acid modified starches. However, the dual modification increased the water vapor permeability of the films without changing their solubility. The increase in sorghum starch concentration in the filmogenic solution increased the thickness, water vapor permeability, and elongation of the films.

Development and characterization of biodegradable films from whey protein concentrate, psyllium husk and oxidized, crosslinked, dual‐modified lotus rhizome starch composite

“…The improved tensile strength of oxidized starch composite films may be attributed to the presence of carbonyl and carboxyl groups in oxidized starches (Table ) which tend to form hydrogen bonds with hydroxyl groups of amylose and amylopectin leading to higher structural integrity of the polymeric matrix . Similar results for an increase in tensile strength have been reported for oxidized banana and sorghum starch films . For crosslinked and dual‐modified starch composite films, tensile strength also increased with an increase in degree of crosslinking.…”

“…Oxidized starch composite films presented highest thickness values among modified starch composite film. The increase in thickness of oxidized starch composite films may be attributed to the presence of carboxyl and carbonyl groups which increased the interaction with glycerol, thereby facilitating water retention during the film drying process . The thickness of crosslinked and dual‐modified starches was observed to be less than that of oxidized starch composite films but increased with an increase in modification level.…”

“…Solubility of biodegradable films varies depending on their usage; films used in products with high moisture content should have low solubility, while edible films should have high solubility in water . Table presents the solubility of native and modified starch composite films.…”

“…The crystallinity of oxidized starch composite films was determined to be higher than that of native starch composite films. The partial cleavage of glycosidic linkages during oxidation might have facilitated the recrystallization of amylose and amylopectin retrogradation in the drying of films, which led to the formation of more crystalline material …”

Novel 1,2,3-triazolium-functionalized starch derivatives: Synthesis, characterization, and evaluation of antifungal property

“…The increasing interest in starch-based biomaterials is due to its interesting properties such as cheap, renewable, biodegradable, and biocompatible Umar et al, 2016), which can facilitate a certain degree of applications of starch in biomedicine, biomaterials, and textile areas (Ahmed, Thomas, Taher, & Joseph, 2016;Nguyen Vu & Lumdubwong, 2016). However, chemical modification via introduction of the individual functional moieties to starch backbone is often necessary in order to further improve the bioactivity and broaden application scope of new valuable biomaterials based on starch (Adak & Banerjee, 2016;Biduski et al, 2017;KapelkoZeberska, Zieba, Spychaj, & Gryszkin, 2015).…”