Effect of pH on formation of starch complexes with lauric acid and β-lactoglobulin

Effect of ultrasound-pretreated starch on the formation, structure and digestibility of starch ternary complexes from lauric acid and β-lactoglobulin

Starch, lipids, and proteins are key macronutrients in starchy foods. Their interactions during processing can form starch-lipid-protein ternary complexes, significantly affecting food quality. Ultrasonic treatment, as a common processing method, is expected to regulate the quality of starchy foods by influencing the formation of ternary complexes. This study aimed to understand the effect of ultrasonic pretreatment on the formation of starch-lipid-protein ternary complexes using various types of starches. Wheat starch (WS), maize starch (MS), and potato starch (PS) were gelatinized and treated with ultrasound at various power densities (0-40 W/L) to form complexes with lauric acid (LA) and β-lactoglobulin (βLG), respectively. Ultrasound increased the amylose content of gelatinized WS, MS, and PS and shifted their chain length distribution towards the short chains. Results from Fourier transform infrared spectroscopy, laser confocal micro-Raman, X-ray diffraction, and differential scanning calorimetry showed that the largest amount of WS-LA-βLG complexes was formed at the ultrasonic power density of 10 W/L, and MS-LA-βLG and PS-LA-βLG complexes at 20 W/L. Additionally, ultrasound enhanced the content of resistant starch (RS) in the starch-LA-βLG complexes. The RS content increased from 14.12 % to 18.31 % for WS-LA-βLG, and from 19.18 % and 20.69 % to 27.60 % and 28.63 % for MS-LA-βLG and PS-LA-βLG complexes, respectively. This study presents an approach for facilitating the formation of ternary complexes, contributing to the development of low-GI functional foods.

New insights into starch, lipid, and protein interactions - Colon microbiota fermentation

Starch, lipids, and proteins are essential biological macromolecules that play a crucial role in providing energy and nutrition to our bodies. Interactions between these macromolecules have been shown to impact starch digestibility. Understanding and controlling starch digestibility is a key area of research. Investigating the mechanisms behind the interactions of these three components and their influence on starch digestibility is of significant practical importance. Moreover, these interactions can result in the formation of resistant starch, which can be fermented by gut microbiota in the colon, leading to various health benefits. While current research has predominantly focused on the digestive properties of starch in the small intestine, there is a notable gap in understanding the colonic microbial fermentation phase of resistant starch. The benefits of fermentation of resistant starch in the colon may outweigh its glucose-lowering effect in the small intestine. Thus, it is crucial to study the fermentation behavior of resistant starch in the colon. This paper investigates the impact of interactions among starch, lipids, and proteins on starch digestion, with a specific focus on the fermentation phase of indigestible carbohydrates in the colon. Furthermore, valuable insights are offered for guiding future research endeavors.

Effect of lecithin on the complexation between different botanically sourced starches and lauric acid

This research investigated the effect of lecithin on the complexation of lauric acid with maize starch, potato starch, waxy maize starch, and high amylose maize starch. Rapid visco analysis showed that lecithin altered the setback pattern of potato starch-lauric acid and maize starch-lauric acid mixtures but not waxy maize starch-lauric acid. Further investigation, including differential scanning calorimetry, complex index, and X-ray diffraction, showed that lecithin enhanced the complexation of maize starch, potato starch, and high amylose maize starch with lauric acid. Fourier transform infrared and Raman spectroscopy revealed increasingly ordered structures formed in maize starch-lauric acid-lecithin, potato starch-lauric acid-lecithin, and high amylose maize starch-lauric acid-lecithin systems compared to corresponding binary systems. These highly ordered complexes of maize starch, potato starch, and high amylose maize starch also demonstrated greater resistance to in vitro enzymatic hydrolysis. Waxy maize starch complexation however remained unaffected by lecithin. The results of this study show that lecithin impacts complexation between fatty acids and native starches containing amylose, with the starch source being critical. Lecithin minimally impacted the complexation of low amylose starch and fatty acids.

Lecithin enhances the complexation between pea starch and fatty acids in aqueous system, and affects the starch's structure and enzymatic hydrolysis

This paper investigates a newly found effect of lecithin on the complexation between starch and saturated fatty acids. Rapid visco analysis showed that adding lecithin to the pea starch-fatty acid mixtures resulted in a viscosity peak during the setback stage of the pasting curve. Subsequent differential scanning calorimetry showed that pea starch-fatty acid-lecithin systems formed more V-type structures than pea starch-fatty acid complexes. X-ray diffraction and Fourier transform infrared spectroscopy indicated the addition of lecithin developed the long-range and short-range order of the V-complexes. Small-angle X-ray scattering showed the ternary system had a more compact stack in nano-scale and smaller D bragg than the binary complex. In vitro enzymatic hydrolysis revealed higher hydrolysis resistance of ternary systems compared to binary complexes. The results of this research provide a mechanism for modifying starch-lipid complexes and contribute to scientific understanding of food ingredient interactions.

Effects of different sources of proteins on the formation of starch-lipid-protein complexes

In the present study, the influence of different sources of proteins on the formation of complexes with starch and lipid were investigated. A model system containing wheat starch (WS), palmitic acid (PA) and four proteins (whey protein isolate, egg white protein, soy protein isolate and pea protein isolate) was used to prepare the complexes by Rapid Visco Analyzer. The addition of PA in the pasted WS-protein systems resulted in higher cooling viscosity compared to the pasted WS-PA systems, which was interpreted as being due to the formation of WS-PA-protein complexes. Analyses from differential scanning calorimetry, X-ray diffraction and Raman spectroscopy showed that more complexes were formed in WS-PA-protein systems than in WS-PA systems, especially in the WS-PA-whey protein isolate. The better emulsifying action of whey protein isolate was proposed to be accountable for the greater amounts of complexes formed compared to other three proteins. This study provides important information about the formation of starch-lipid-protein complexes in regard to the selection of proteins for food processing.

Effect of the Amylose Nanoscale Polymerization Index on the Digestion Kinetics and Mechanism of Recombinant Chinese Seedless Breadfruit Starch Triadic Complexes

The demand for multicomponent foods to meet human energy and nutritional needs has been increasing; however, few studies have addressed the theoretical basis for their preparation. We investigated the effect of the nanoscale polymerization index (DPw) of amylose on the logarithm of slope plot-based kinetics and the mechanism of digestion of starch-lauric acid-β-lactoglobulin protein complexes. Amylose from each of the five Chinese seedless breadfruit species was mixed with breadfruit amylopectin with the highest resistant starch (RS) content to form starch ternary complexes with various amylose DPws. All five complexes exhibited V-type crystalline diffraction and rod-like molecular configuration. Characteristic X-ray diffraction peaks and Fourier transform-infrared spectra of the ternary complexes revealed similar molecular configurations. As the amylose DPw increased, the complexing index, relative crystallinity, short-range order, weight-average molar mass, molecular density index, gelatinization temperature, decomposition temperature, RS, slowly digestible starch (SDS), and speed rate constants at the second hydrolysis stage (k₂) increased, whereas the semicrystalline lamellae thickness, mass fractal structure parameter, average characteristic crystallite unit length, radius of gyration, fractal dimension and cavities of granule surface microstructure, final viscosity, interval speed rate from SDS to RS, equilibrium concentration, and glycemic index decreased. The digestion kinetics exhibited highly significant variation according to the physiochemical properties and multiscale supramolecular structure (r > 0.99 or r < -0.99, p < 0.01). Together, these results identify amylose DPw as an important structural factor that markedly affects the kinetics and mechanism of ternary complex digestion and provide a new theoretical direction for the production of starch-based multicomponent foods.

Dietary compounds slow starch enzymatic digestion: A review

Dietary compounds significantly affected starch enzymatic digestion. However, effects of dietary compounds on starch digestion and their underlying mechanisms have been not systematically discussed yet. This review summarized the effects of dietary compounds including cell walls, proteins, lipids, non-starchy polysaccharides, and polyphenols on starch enzymatic digestion. Cell walls, proteins, and non-starchy polysaccharides restricted starch disruption during hydrothermal treatment and the retained ordered structures limited enzymatic binding. Moreover, they encapsulated starch granules and formed physical barriers for enzyme accessibility. Proteins, non-starchy polysaccharides along with lipids and polyphenols interacted with starch and formed ordered assemblies. Furthermore, non-starchy polysaccharides and polyphenols showed robust abilities to reduce activities of α-amylase and α-glucosidase. Accordingly, it can be concluded that dietary compounds lowered starch digestion mainly by three modes: (i) prevented ordered structures from disruption and formed ordered assemblies chaperoned with these dietary compounds; (ii) formed physical barriers and prevented enzymes from accessing/binding to starch; (iii) reduced enzymes activities. Dietary compounds showed great potentials in lowering starch enzymatic digestion, thereby modulating postprandial glucose response to food and preventing or treating type II diabetes disease.

Mechanisms Underlying the Formation of Amylose- Lauric Acid-β-Lactoglobulin Complexes: Experimental and Molecular Dynamics Studies

The aim of the present study was to reveal the mechanisms underlying the formation of ternary complexes with a model system of amylose (AM), lauric acid (LA), and β-lactoglobulin (βLG) using experimental studies and molecular dynamics (MD) simulations. Experimental analyses showed that hydrophobic interactions and hydrogen bonds contributed more than electrostatic forces to the formation of the AM-LA-βLG complex. MD simulations indicated that interactions between AM and βLG through electrostatic forces and hydrogen bonds, and to a less extent van der Waals forces, and interactions between AM and LA through van der Waals forces, were mostly responsible for complex formation. The combination of experimental results and MD simulations has provided new mechanistic insights and led us to conclude that hydrophobic interactions, van der Waals forces between AM and LA, and van der Waals forces and hydrogen bonds between AM and βLG were the main driving forces for the formation of the AM-LA-βLG complex.