Characterization, in vitro digestibility and release properties of starch-linoleic acid-sodium alginate composite film.

This study aimed to improve the complexing degree, digestibility and controlled release properties of the potato starch (PS)-linoleic acid (LA) complexes by encapsulating PS-LA complexes to sodium alginate (AG) beads. The results revealed that AG had a positive effect on the complexing index, R1047/1022 values, relative crystallinity, enthalpy and morphological structure of PS-LA-AG films, especially for PS-LA-AG film with the PS-LA: AG of 5:1. The in vitro digestion and hydrolysis kinetic analysis indicated that AG addition reduced the digestibility of PS-LA-AG films to a higher slowly digestible starch content and resistant starch content and a lower equilibrium hydrolysis percentage and kinetic constant. Furthermore, in vivo release study of PS-LA-AG films indicated a restrained release in simulated gastrointestinal conditions. Consequently, the results indicated that AG addition significantly improved the inclusion efficiency for the complex formation between PS and LA, which was beneficial for the design of resistant films to entrap and control release of unsaturated fatty.

Understanding the aggregation structure, digestive and rheological properties of corn, potato, and pea starches modified by ultrasonic frequency.

Corn starch (CS), potato starch (PtS), and pea starch (PS) were modified by ultrasonic frequency (codes as UFCS, UFPtS and UFPS), and changes in aggregation structure, digestibility and rheology were investigated. For UFCS, the apparent amylose content and gelatinization enthalpy (∆H) decreased, while the R1047/1022 values and relative crystallinity (RC) increased under lower ultrasonic frequencies (20 kHz and 25 kHz). For UFPtS, the apparent amylose content, R1047/1022 values and RC increased, while the ∆H decreased under a higher ultrasonic frequency (28 kHz). For UFPS, the apparent amylose content, R1047/1022 values, RC, ∆H decreased at 20 kHz, 25 kHz and 28 kHz. Cracks were observed on the surface of UFCS, UFPtS and UFPS. These aggregation structure changes increased the resistant starch content to 31.11% (20 kHz) and 26.45% (25 kHz) for UFCS and to 39.68% (28 kHz) for UFPtS, but decreased the resistant starch content to 18.46% (28 kHz) for UFPS. Consistency coefficient, storage modulus, and loss modulus of UFCS, UFPtS and UFPS increased, while the flow behavior index and damping factor decreased. Results indicated that CS, PtS and PS had diverse digestion and rheology behaviors after ultrasonic frequency modification, which fulfilled different demands in starch-based products.

Changes in structural, digestive, and rheological properties of corn, potato, and pea starches as influenced by different ultrasonic treatments.

Ultrasound was widely used in starch modification, whereas there was no review focusing on the effects of different ultrasonic treatments on A-, B- and C-type starches. In this study, the effects of ultrasonic power (UP, 100-600 W) and ultrasonic time (UT, 5-35 min) on structural, digestibility and rheology of corn starch (CS), potato starch (PtS), and pea starch (PS) were investigated. As a result, UP and UT decreased the apparent amylose content of CS and PS, while increased the apparent amylose content of PtS. UP and UT enhanced R1047/1022 values of CS, whereas those of PtS and PS were decreased. Moreover, UP and UT decreased the gelatinization enthalpy of CS, PtS and PS. In vitro digestion revealed that UP and UT decreased the resistant starch content of PtS and PS, but increased the resistant starch content of CS. Rheological tests indicated that UP and UT decreased the flow behavior index of CS, PtS and PS pastes, and caused an increase in storage modulus and loss modulus. Results revealed that ultrasonic treatment represented a promising technology to obtain CS, PtS and PS with tailored digestibility and rheology, which allowed the texture and glycemic response of starch-based products to be adjusted.