Estimation of aqueous solubility of starch from various botanical sources using Flory Huggins theory approach

Combining pulsed electric field and cross-linking to enhance the structural and physicochemical properties of corn porous starch

In this study, corn porous starch (CPS) was firstly prepared using enzymatic hydrolysis, followed by pore formation enhancement using the treatment of a pulsed electric field (PEF). Subsequently, the PEF treated porous starch (CPS-PEF) was cross-linked with sodium trimetaphosphate (STMP) to investigate its structural and functional properties. The results showed PEF treatment increased the oil absorption of CPS by 26.92% and improved its specific surface area, total pore volume value, solubility and swelling power. After cross-linking of the CPS-PEF, C-O-P covalent bonds were formed between CPS-PEF molecules, resulting in a further increase in oil absorption and specific surface area properties. Moreover, the covalent bonds enhanced the intermolecular forces, resulting in increased thermal stability of the cross-linked porous starch (ScPS). The double modification resulted in significantly improved adsorption properties and better thermal stability of the ScPS, indicating that the double modification is an effective method for the preparation of porous starches.

Temperature responsive crosslinked starch-kraft lignin macromolecule

Starch is a natural polymer with a relatively simple structure and limited solubility in water. Kraft lignin (KL) is a complex biopolymer obtained as a by-product from the delignification of wood and grasses. The present work reports developing a temperature-responsive high molecular weight macromolecule from crosslinking KL and starch (KLS). The NMR and XPS analyses quantified the changes in the aromatic and anhydroglucose units of KL and starch, observing a higher content of C-O-C bonds, which confirms the presence of glycerol ether cross-linkages between starch and KL in KLS. The rheological analysis of KLS dispersions revealed the formation of a thermo-responsive structured network. The temperature-dependent water solubility and rheological characteristics of KLS were related to the presence of hydrophilic starch chains, crosslinking degree, and physicochemical characteristics of KL. The incorporation of KL and ether crosslinks increased the thermal stability of KLS. Because of its multiple functional groups and large molecular weight (3.6-4.2 × 10⁵ g/mol) that was arranged in an extended globular shape, KLS-5 formed a gel-like structure after a heating-cooling treatment. Overall, the results confirmed that incorporating lignin in starch would fabricate sustainable materials with potentially altered applications, such as temperature-responsive hydrogels and films.

Optimization of Concentration-Time, Agar, and Sugar Concentration for Sweet Gelatinized Adzuki-Bean Jelly Cake (Yokan) by Response Surface Methodology

Samples of sweet gelatinized adzuki-bean jelly cake were successfully prepared and systematically analyzed to investigate the factors that affect the production, quality, and gelatin properties of yokan (gelatinized adzuki bean cake). The purpose of this study was to investigate the properties of gelatinized adzuki-bean cake gelatin and identify the optimal production conditions using response surface methodology with three factors: agar concentration, sugar concentration, and concentration time. Findings show that the optimum processing conditions are 1.2-1.5% agar concentration and 34-40% sugar concentration, with 30-40 min concentration time. These conditions produced a gelatinized adzuki-bean cake favored by the majority of the sensory evaluators. Overall, the relationships between different gelatinized adzuki-bean cake processing conditions and gelatin properties were preliminarily clarified. The findings not only provide a promising avenue for gelatinized adzuki-bean cake production but also promote the potential application of various processing conditions in quality improvement.