Characterizing internal cavity modulation of corn starch microcapsules

Extraction process, physicochemical properties, and digestive performance of red yeast rice starch

In the present study, taking red yeast rice (RYR) as the raw material, the optimum extraction process of RYR starch was investigated through a single-factor experiment and the Box-Behnken design: The liquid-to-solid ratio was 5 mL/g, the concentration of sodium hydroxide solution was 0.075 mol/L, and the extraction time was 3.1 h. Under these extraction conditions, the extraction rate of starch reached 90.077%. To explore the influence of solid-state fermentation on RYR starch, three different fermentation stages of RYR starch, raw rice starch, semi-gelatinized rice starch, and RYR starch were used as test materials to determine the changes in the physicochemical properties and glycemic index (GI) values of RYR starch during solid-state fermentation. The results showed that with the advancement of the RYR solid-state fermentation process, the starch particle size gradually increased, the light transmittance gradually decreased, and the solubility and swelling power significantly increased. In addition, the amylose content of starch gradually increased, whereas the amylopectin content gradually decreased; the content of fast digestible starch and slow digestible starch decreased, whereas the content of resistant starch increased. In parallel, during solid-state fermentation, the hydrolysis index significantly decreased, and the GI values also decreased. In summary, solid-state fermentation reduced the digestibility of RYR starch. These results provide a theoretical basis for the structural and physicochemical properties of RYR starch and lay a foundation for its subsequent application and expansion of RYR starch.

Self-healing properties of retrograded starch films with enzyme-treated waxy maize starch as healing agent

Waxy maize starch (WMS) was modified using sequential α-amylase and transglucosidase to create enzyme-treated waxy maize starch (EWMS) with higher branching degree and lower viscosity as an ideal healing agent. Self-healing properties of retrograded starch films with microcapsules containing WMS (WMC) and EWMS (EWMC) were investigated. The results indicated that EWMS-16 had the maximum branching degree of 21.88 % after transglucosidase treatment time of 16 h, and A chain of 12.89 %, B1 chain of 60.76 %, B2 chain of 18.82 % and B3 chain of 7.52 %. The particle sizes of EWMC ranged from 2.754 to 5.754 μm. The embedding rate of EWMC was 50.08 %. Compared to retrograded starch films with WMC, water vapor transmission coefficients of retrograded starch films with EWMC were lower, while tensile strength and elongation at break values of retrograded starch films were almost similar. Retrograded starch films with EWMC had higher healing efficiency of 58.33 % as compared to that Retrograded starch films retrograded starch films with WMC was 44.65 %.

Preparation of starch-based functional food nano-microcapsule delivery system and its controlled release characteristics

Most of the functional substances in food are absorbed in the small intestine, but before entering the small intestine, the strong acid and enzymes in the stomach limit the amount that can reach the small intestine. Therefore, in this paper, to develop a delivery system for functional food ingredients, maintain the biological activity of the ingredients, and deliver them to the target digestive organs, preparation of starch-based functional food nano-microcapsule delivery system and its controlled release characteristics were reviewed. Embedding unstable food active ingredients in starch-based nano-microcapsules can give the core material excellent stability and certain functional effects. Starch-based wall materials refer to a type of natural polymer material that uses starch or its derivatives to coat fat-soluble components with its hydrophobic cavities. The preparation methods of starch-based wall materials mainly include spray drying, extrusion, freeze drying, ultra-high pressure, coagulation, fluidized bed coating, molecular inclusion, chemical, and enzymic methods. The controlled release of functional food can be achieved by preparing starch-based nano-microcapsules to encapsulate the active agents. It has been reported that that compared with traditional embedding agents such as gelatin, acacia gum, and xanthan gum, starch-based functional food nano-microcapsule delivery system had many good properties, including improving antioxidant capacity, bioavailability, probiotics, and concealing bad flavors. From this review, we can learn which method should be chosen to prepare starch-based functional food nano-microcapsule delivery system and understand the mechanism of controlled release.

Microencapsulated procyanidins by extruding starch improved physicochemical properties, inhibited the protein and lipid oxidant of chicken sausages

Microencapsulated procyanidins by extruding starch (MPS) were used in meat and meat products as an antioxidant for their simple production process and high stability. This study investigated the controlled released properties of MPS and their effect on antioxidant capacity, physicochemical properties, and sensory qualities of chicken sausages during 4°C storage within 28 days. Antioxidant capacity, particle size analysis, and simulated digestion in vitro demonstrated that microencapsulation by extruding starch delayed the procyanidins release. The reduced crystal structure of MPS was determined by the morphology observation (SEM) and the decrease of the typical diffraction peak at 2θ of 20.9° (XRD). The MPS-added sausage had a higher (p < 0.05) ABTS and DPPH radical scavenging ratio (97.6% and 67.3%) and sulfhydryl contents (114.69 nmol/g protein) than other groups. Moreover, lower (p < 0.05) thiobarbituric acid reactive substances (TBARS) (0.67 mg MDA/kg sausage) and carbonyl values (3.24 nmol/mg protein) were detected in MPS-added sausages than others at the end of storage. The MPS addition increased redness (a* value) and decreased the lightness (L* value). The sensory analysis suggested that the sausage with the increased redness was favorable. These results denominated that MPS was an alternative antioxidant in chicken sausages. Practical Application: In this study, microencapsulated procyanidins were prepared by extrusion technology, and the effect on the quality of chicken sausages was investigated, which provides an alternative natural antioxidant for meat and meat products.

Development and Characterization of Active Native and Cross-Linked Pearl Millet Starch-Based Film Loaded with Fenugreek Oil

In this study, cross-linked pearl millet starch and fenugreek oil was used to develop active starch edible films to overcome the limitations of native starch and to substitute artificial preservatives with natural one. The starch was cross-linked at three levels (1%, 3% and 5%) using sodium trimetaphosphate (STMP), and physicochemical properties were studied. Moreover, a comparative study was conducted among four samples of films prepared using native starch, cross-linked starch, and native and cross-linked starch loaded with fenugreek oil for physical, thermal, mechanical, morphological, and antibacterial properties. The solubility, swelling, and amylose content of native and modified starch varied from 11.25–12.75%, 12.91–15.10 g/g, and 8.97–16.55%, respectively. The values of these parameters were reduced as the concentration of STMP increased. Cross-linked starch films showed lower moisture, solubility, water vapor permeability(WVP), and elongation at break (EB) values while having higher thickness, opacity, thermal, and tensile strength values. The microscopic images of cross-linked starch films showed smooth surfaces and the absence of ridges, pores, and cracks. The films loaded with fenugreek oil showed different results; the moisture content, water solubility, and tensile strength were decreased while thickness, opacity, WVP, and EB were increased. The onset temperature and peak temperature were lower, while enthalpy of gelatinization was increased to a greater extent than films without oil. The addition of fenugreek oil to films showed a good inhibition area of 40.22% for native+oil films and 41.53% for cross-linked+oil films % against Escherichia coli. This study confirmed the successful utilization of fenugreek oil as a very effective antimicrobial agent in preparing edible films.