Plasticization Efficiency and Characteristics of Monosaccharides, Disaccharides, and Low-Molecular-Weight Polysaccharides for Starch-Based Materials

Abstract

In this work, the saccharides with different structures and molecular weights were evaluated as a plasticizer for starch-based materials, in which the saccharides from monosaccharides, such as glucose, mannose, fructose, xylose, and disaccharides including sucrose and maltose, to dextrin with different molecular weights, were used. As expected, starch and these saccharides are fully compactable and miscible since they have similar chemical components. These saccharides must work together with water or polyols to act as co-plasticizers since they are all in solid-state under dry conditions. Many monosaccharides or disaccharides with ring structures can stably stay in the starch matrix without affecting the microstructures of the polymer chains significantly, but the monosaccharides with linear structures, such as fructose and xylose, showed much more efficiency to destroy the ordered structures and enhance the movement of polymer chains, which results in higher efficiency of plasticization. All these saccharides can generally increase the stability of moisture containing in the starches because of the strong bonding by hydroxyl groups. Thermal properties of the starch-based films were investigated by differential scanning calorimetry, thermal-gravimetric analysis, and dynamic mechanical analysis, and morphologies and microstructures of the films were studied by scanning electron microscopy and X-ray diffraction. These saccharides did not affect the gelatinization temperature of the starch. Both T g and crystallinity of starch were decreased with additional saccharides, indicating that the rigid crystalline range in starch was destroyed. This research not only increased the knowledge of the plasticizing mechanism but also can be used for developing various starch-based products, including food and packaging.

Synergizing Multi-Plasticizers for a Starch-Based Edible Film

“…Both water and glycerol are liquid at room temperature. However, glycerol still must work together with water as a plasticizer since the strong hydroxy bound, even the esterification reaction between starch and glycerol under water free conditions, reduces the movement of the starch chain [ 28 ]. Sorbitol has a strong water solubility; thus, it should also be in a liquid state when mixed with water.…”

“…More recently, the chemicals containing multi-hydroxyl groups have also been developed as plasticizers for starch-based materials, such as sorbitol [ 27 ] and xylose, etc. [ 28 ]. They are all food ingredients.…”

Developing Edible Starch Film Used for Packaging Seasonings in Instant Noodles

“…CA was slightly enhanced by xylose, indicating that the hydrophobicity of the starch film marginally increased. The hydroxyl groups in linear xylose are more flexible and face out, which makes sense [ 33 ].…”

Deep Eutectic Solvents for Starch Treatment

“…In the presence of the substance that is able to form hydrogen bonds with polysaccharide chains (plasticizer) at an elevated temperature and shear stress, the granular structure of starch is disrupted, and thermoplastic starch (TPS) could be obtained. For many years, research on starch plasticizers, such as urea [2], glycerol and other polyols [3], sugars [4], and formamide [5], were performed. However, the mechanical properties of the obtained materials depended on the moisture content; moreover, they exhibited a tendency to retrogradation (recrystallization), and some plasticizers were toxic [6].…”