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Starch is a readily available and abundant source of biological raw materials and is widely used in the food, medical, and textile industries. However, native starch with insufficient functionality limits its utilization in the above applications; therefore, it is modified through various physical, chemical, enzymatic, genetic and multiple modifications. This review summarized the relationship between structural changes and functional properties of starch subjected to different modified methods, including hydrothermal treatment, microwave, pre-gelatinization, ball milling, ultrasonication, radiation, high hydrostatic pressure, supercritical CO2, oxidation, etherification, esterification, acid hydrolysis, enzymatic modification, genetic modification, and their combined modifications. A better understanding of these features has the potential to lead to starch-based products with targeted structures and optimized properties for specific applications. [ABSTRACT FROM AUTHOR]

Zeaxanthin is a natural xanthophyll carotenoid and the main macular pigment that protects the macula from light-initiated oxidative damage, but it has poor stability and low bioavailability. Absorption of this active ingredient into starch granules as a carrier can be used to improve both zeaxanthin stability and controlled release. Optimization using three variables judged important for optimizing the system (reaction temperature of 65 °C, starch concentration of 6%, and reaction time of 2 h) was conducted for incorporation of zeaxanthin into corn starch granules, aiming for high zeaxanthin content (2.47 mg/g) and high encapsulation efficiency (74%). Polarized-light microscopy, X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopy showed that the process partially gelatinized corn starch; additionally, it showed the presence of corn starch/zeaxanthin composites, with the zeaxanthin successfully trapped in corn starch granules. The half-life time of zeaxanthin in corn starch/zeaxanthin composites increased to 43 days as compared with that of zeaxanthin alone (13 days). The composites show a rapid increase in zeaxanthin release with in vitro intestinal digestion, which is favorable for possible use in living systems. These findings could have application in designing effective starch-based carriers of this bioactive ingredient with enhanced storage stability and improved intestines-targeted controlled-release delivery. [ABSTRACT FROM AUTHOR]

In this study, caffeine (CA) was encapsulated into food-grade starch matrices, including swelled starch (SS), porous starch (PS), and V-type starch (VS). The bitterness of the microcapsules and suppression mechanisms were investigated using an electronic tongue, molecular dynamics (MD) simulation and the in vitro release kinetics of CA. All the CA-loaded microcapsules showed a lower bitterness intensity than the control. The MD results proved that the weak interactions between starch and CA resulted in a moderate CA release rate for SS-CA microcapsules. The PS-CA microcapsule presented the longest CA release, up to 40 min, whereas the VS-CA microcapsule completely released CA in 9 min. The CA release rate was found to be related to the microcapsule structure and rehydration properties. A low CA bitterness intensity could be attributed to a delay in the CA release rate and resistance to erosion of the microcapsules. The results of this work are valuable for improving starch-based microcapsules (oral-targeted drug-delivery systems) by suppressing the bitterness of alkaloid compounds. Unlabelled Image • Caffeine (CA) loaded in starch microcapsules could delay its release rate. • Porous starch loaded CA showed the slowest release rate. • The diffusion path and swelling ratio affect CA bitterness suppression. • CA bitterness suppression was influenced by intermolecular interactions and release rate. [ABSTRACT FROM AUTHOR]

Oil structuring from porous starch is a potential alternative for the industrial production of powdered oil, but their relationship between starch multi-scale structure and oil adsorption characteristics was not clear. This study compared the role of multi-scale structure of porous starch (PS) prepared by normal and waxy maize starch in the oil adsorption. Waxy maize porous starch exhibited higher oil adsorption capacity (32.43 %–98.71 %) and more oil distributed on the surface of granules than normal maize porous starch, resulting from the more pores, larger specific surface area (1.01–1.53 m2/g), and pore size (8.45–9.32 nm). The enzymolysis time of native starch dominated oil distribution, leading to different granule adhesion and aggregation state. Pearson correlation analysis further showed oil adsorption capacity was negatively correlated with particle size, but positively correlated with enzymolysis rate and specific surface area of PS. The formation of powdered oil was mainly through the physical adsorption, including surface adsorption and pore adsorption. These findings could provide a promising route for the preparation of powdered oil with controlled multi-scale structure of PS. • Porous starch (PS) was used as oil structuring agents to produce powdered oil. • High enzymolysis rate enhanced oil adsorption capacity, leading to granule aggregation. • The granule structure determined oil adsorption capacity and oil distribution of PS. • The formation of powdered oil was mainly attributed to the physical adsorption. [ABSTRACT FROM AUTHOR]

Swelled cornstarch granules incubated at different incubation temperatures was prepared as a complexation matrix to encapsulate lutein. Increasing incubation temperature (55–70 °C) induced the gelatinization of cornstarch, resulting in enhancement of swelling power (1.67–6.26 g/g) and lutein content (0.78–4.86 mg/g). A decreased (double helix of amylopectin) and an increased (single helix of V-amylose) enthalpy change were associated with the increased incubation temperature. The retention index of lutein in the composites incubated at 65 °C and 70 °C could achieve 76% after 21 days of storage. Less than 30% of lutein in the composites was released after incubating for 120 min under stomach conditions. Fast lutein release was observed during the first 20 min intestinal digestion, consistent with starch hydrolysis data. This study opens a promising pathway for swelled cornstarch granules as delivery carriers of bioactive ingredients, which are of vital importance for their potential use in the sensitive food supplement. [ABSTRACT FROM AUTHOR]

[Display omitted] • The starches of three new varieties of corn cultivated by our team were investigated. • The structure and properties of 8 kinds of waxy, sweet waxy corn starch were studied. • The corn varieties that could replace waxy rice development products were identified. To explore the feasibility of substituting waxy rice with waxy or sweet-waxy corn, eight varieties of waxy and sweet-waxy corns were selected, including three self-cultivated varieties (Feng nuo 168, Feng nuo 211, and Feng nuo 10). Their starches were isolated and used as research objects, and commercially available waxy rice starch (CAWR) and waxy corn starch (CAWC) were used as controls. X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, rapid viscosity analyzer, and rotational rheometer were used to analyze their physicochemical and structural characteristics. The morphologies of all corn starch granules were generally oval or round, with significant differences in particle size distributions. All ten starches exhibited a typical A-type crystal structure; however, their relative crystallinity varied from 20.08% to 31.43%. Chain length distribution analysis showed that the A/B ratio of Jing cai tian nuo 18 and Feng nuo 168 was similar to that of CAWR. Peak viscosities of corn starches were higher than that of CAWR, except for Feng nuo 10, while their setback values were lower than that of CAWR. Except for Feng nuo 10, the paste transparency of corn starches was higher than that of CAWR (10.77%), especially for Jing cai tian nuo 18 (up to 24%). In summary, Jing cai tian nuo 18 and Feng nuo 168 are promising candidates to replace CAWR in developing various rice-based products. [ABSTRACT FROM AUTHOR]

Starch-based composite nanofibrous films loaded with tea polyphenols (TP) were successfully fabricated through electrospinning high amylose corn starch (HACS) with aid of polyvinyl alcohol (PVA), referred as HACS/PVA@TP. With the addition of 15 % TP, HACS/PVA@TP nanofibrous films exhibited enhanced mechanical properties and water vapor barrier capability, and their hydrogen bonding interactions were further evidenced. TP was slowly released from the nanofibrous film and followed Fickian diffusion mechanism, which achieved the controlled sustained release of TP. Interesting, HACS/PVA@TP nanofibrous films effectively improved antimicrobial activities against Staphylococcus aureus (S. aureus) and prolonged the shelf life of strawberry. HACS/PVA@TP nanofibrous films showed superior antibacterial function by by destroying cell wall and cytomembrane, and degrading existing DNA fragments, stimulating excessive intracellular reactive oxygen species (ROS) generation. Our study demonstrated that the functional electrospun Starch-based nanofibrous films with enhanced mechanical properties and superior antimicrobial activities were potential for the application in active food packaging and relative areas. • Electrospun HACS/PVA@TP nanofibrous film was fabricated. • HACS/PVA@TP nanofibrous film exhibited enhanced mechanical properties. • HACS/PVA@TP nanofibrous film achieved the controlled sustained release of TP. • HACS/PVA@TP nanofibrous film improved antimicrobial activities against S. aureus. • HACS/PVA@TP nanofibrous film prolonged the shelf life of strawberry. [ABSTRACT FROM AUTHOR]