Effect of porous waxy rice starch addition on acid milk gels: Structural and physicochemical functionality

Expanded porous-starch matrix as an alternative to porous starch granule: Present status, challenges, and future prospects

Exposing the hydrated-soft-starch matrix of intact grain or reconstituted flour dough to a high-temperature-short-time (HTST) leads to rapid vapor generation that facilitates high-pressure build-up in its elastic matrix linked to large deformation and expansion. The expanded starch matrix at high temperatures dries up quickly by flash vaporization of water, which causes loss of its structural flexibility and imparts a porous and rigid structure of the expanded porous starch matrix (EPSM). EPSM, with abundant pores in its construction, offers adsorptive effectiveness, solubility, swelling ability, mechanical strength, and thermal stability. It can be a sustainable and easy-to-construct alternative to porous starch (PS) in food and pharmaceutical applications. This review is a comparative study of PS and EPSM on their preparation methods, structure, and physicochemical properties, finding compatibility and addressing challenges in recommending EPSM as an alternative to PS in adsorbing, dispersing, stabilizing, and delivering active ingredients in a controlled and efficient way.

Effect and Mechanism of Soluble Starch on Bovine Serum Albumin Cold-Set Gel Induced by Microbial Transglutaminase: A Significantly Improved Carrier for Active Substances

Soluble starch (SS) could significantly accelerate the process of bovine serum albumin (BSA) cold-set gelation by glucono-δ-lactone (GDL) and microbial transglutaminase (MTGase) coupling inducers, and enhance the mechanical properties. Hardness, WHC, loss modulus (G″) and storage modulus (G') of the gel increased significantly, along with the addition of SS, and gelation time was also shortened from 41 min (SS free) to 9 min (containing 4.0% SS); the microstructure also became more and more dense. The results from FTIR, fluorescence quenching and circular dichroism (CD) suggested that SS could bind to BSA to form their composites, and the hydrogen bond was probably the dominant force. Moreover, the ability of SS to bind the original free water in BSA gel was relatively strong, thereby indirectly increasing the concentration of BSA and improving the texture properties of the gel. The acceleration of gelling could also be attributed to the fact that SS reduced the negative charge of BSA aggregates and further promoted the rapid formation of the gel. The embedding efficiency (EE) of quercetin in BSA-SS cold-set gel increased from 68.3% (SS free) to 87.45% (containing 4.0% SS), and a controlled-released effect was detected by simulated gastrointestinal digestion tests. The work could put forward new insights into protein gelation accelerated by polysaccharide, and provide a candidate for the structural design of new products in the food and pharmaceutical fields.

Construction of caffeic acid modified porous starch as the dual-functional microcapsule for encapsulation and antioxidant property

A dual-functional food-grade microcapsule, which was constructed by caffeic acid and porous starch was obtained. Caffeic acid modified porous starch (CA-PS) was accordingly synthesized successfully by esterification. Carbonyl signal observed by ¹³C solid state NMR (170 ppm) and FT-IR (1745 cm^-1), indicating the formation of ester bond. BET of CA-PS was determined as 44.8 m²/g by N₂ adsorption analysis. The results proved CA-PS has both excellent adsorption and antioxidant activity. Furthermore, it has been applied for encapsulation of linoleic acid (LA) to prevent its degradation effectively, because LA adsorbed in porous adsorbents without antioxidant activity may still suffer serious oxidation. Besides, ¹H NMR Integral of LA did not show a significant decay. This observation demonstrated CA-PS indeed has the better performance on protection of LA than PS. We expect this work will boost research on designing and employing multi-functional starchy materials for further applications.

Effect of NaCl addition on alcohol-alkali-treated waxy rice starch: Structural and physicochemical functionality

The physicochemical and structural properties of waxy rice starch (WRS) and alcohol-alkali-treated waxy rice starch (AAT-WRS) were determined in the presence of different concentrations of NaCl (0, 2, 4, 6 and 8%). The results showed that NaCl decreased the transparency of WRS and AAT-WRS pastes, but enhanced both freeze-thaw stability and apparent viscosity (p < 0.05). The rheological measurement results showed that the addition of NaCl could improve the modulus values of both WRS and AAT-WRS, and the effect on WRS was more significant than that on AAT-WRS. The textural parameters of WRS pastes were evidently enhanced by NaCl, but the presence of NaCl had no significant effect on the firmness of AAT-WRS pastes. The results of SEM and FT-IR revealed that NaCl could protect the granular morphology and increase the degree of short-range order of WRS and AAT-WRS.

Structure and Menthone Encapsulation of Corn Starch Modified by Octenyl Succinic Anhydride and Enzymatic Treatment

In order to improve the ability of starch to absorb menthone, corn starch was modified by enzymatic treatment (amyloglucosidase and α-amylase) combined with octenyl succinic anhydride (OSA) esterification. The oil absorption rate of starch modified by enzymatic treatment followed by OSA (P-OSA) reached 101.33%, whereas that of samples with reverse action sequences (OSA-P) was only 59.67%. The degree of substitution of OSA-P was also generally lower than that of P-OSA. At high OSA addition, OSA-P had a smaller specific surface area with fewer pores because octenyl succinic (OS) groups impeded the enzymatic treatment. Compared with OSA-P, the lamellar structure of P-OSA is sparser and less ordered. Owing to its pores, P-OSA was beneficial for the reaction to occur inside the granules, which was observed by Raman spectroscopy and laser confocal microscopy. At high OSA addition, the loading of P-OSA to menthone could reach 64.34 mg/g.