Ultrasonic‐Assisted Preparation of Maize Starch–Caffeic Acid Complex: Physicochemical and Digestion Properties

Research progress on the regulation of starch-polyphenol interactions in food processing

Starch is a fundamental material in the food industry. However, the inherent structural constraints of starch impose limitations on its physicochemical properties, including thermal instability, viscosity, and retrogradation. To address these obstacles, polyphenols are extensively employed for starch modification owing to their distinctive structural characteristics and potent antioxidant capabilities. Interaction between the hydroxyl groups of polyphenols and starch results in the formation of inclusion or non-inclusion complexes, thereby inducing alterations in the multiscale structure of starch. These modifications lead to changes in the physicochemical properties of starch, while simultaneously enhancing its nutritional value. Recent studies have demonstrated that both thermal and non-thermal processing exert a significant influence on the formation of starch-polyphenol complexes. This review meticulously analyzes the techniques facilitating complex formation, elucidating the critical factors that dictate this process. Of noteworthy importance is the observation that thermal processing significantly boosts these interactions, whereas non-thermal processing enables more precise modifications. Thus, a profound comprehension and precise regulation of the production of starch-polyphenol complexes are imperative for optimizing their application in various starch-based food products. This in-depth study is dedicated to providing a valuable pathway for enhancing the quality of starchy foods through the strategic integration of suitable processing technologies.

Ultrasound-assisted annealing treatment to improve physicochemical and digestive properties of banana flour

BACKGROUND

Banana flour can provide a solution to people with gluten intolerance, as it is gluten-free. Native banana flour may have limited functionality in certain applications. In this study, banana flour was modified by ultrasonic (US) and annealing (ANN) treatments at four incubation time spans, namely 12, 24, 36 and 72 h, separately or combined sequentially (US-ANN) to enhance the physicochemical and digestive properties.

RESULTS

US led to exposed granular surfaces and damaged non-starch components. Both treatments, at extended incubation time, increased crystallinity, resulting in a narrower starch gelatinization temperature range. The swelling power was significantly lower for ANN and US-ANN compared to US alone, providing a delay of gelatinization temperature. However, none of the treatments affected the gelatinization enthalpy. Furthermore, US increased peak viscosity, breakdown, final viscosity and setback whereas the opposite results were obtained for ANN and US-ANN. Additionally, US prior to ANN significantly increased the resistant starch (RS) content for annealing times over 24 h, especially for the US-ANN treatment for 72 h, which provided the highest RS content (49.3%) compared to ANN treatment for 72 h (44.0%) and native flour (36.3%).

CONCLUSIONS

US prior to ANN treatment offers an alternative method to improve the functional and digestive properties of banana flour, extending the range of applications. © 2024 Society of Chemical Industry.

Effects of plasma-activated water combined with ultrasonic treatment of corn starch on structural, thermal, physicochemical, functional, and pasting properties

In this study, corn starch was used as the raw material, and modified starch was prepared using a method combining plasma-activated water and ultrasound treatment (PUL). This method was compared with treatments using plasma-activated water (PAW) and ultrasound (UL) alone. The structure, thermal, physicochemical, pasting, and functional properties of the native and treated starches were evaluated. The results indicated that PAW and UL treatments did not alter the shape of the starch granules but caused some surface damage. The PUL treatment increased the starch gelatinization temperature and enthalpy (from 11.22 J/g to 13.13 J/g), as well as its relative crystallinity (increased by 0.51 %), gel hardness (increased by 16.19 %) compared to untreated starch, without inducing a crystalline transition. The PUL treatment resulted in a whitening of the samples. The dual treatment enhanced the thermal stability of the starch paste, which can be attributed to the synergistic effect between PAW and ultrasound (PAW can modify the starch structure at a molecular level, while ultrasound can further disrupt the granule weak crystalline structures, leading to improved thermal properties). Furthermore, FTIR results suggested significant changes in the functional groups related to the water-binding capacity of starch, and the order of the double-helical structure was disrupted. The findings of this study suggest that PUL treatment is a promising new green modification technique for improving the starch structure and enhancing starch properties. However, further research is needed to tailor the approach based on the specific properties of the raw material.

Formation and Application of Starch-Polyphenol Complexes: Influencing Factors and Rapid Screening Based on Chemometrics

Understanding the nuanced interplay between plant polyphenols and starch could have significant implications. For example, it could lead to the development of tailor-made starches for specific applications, from bakinag and brewing to pharmaceuticals and bioplastics. In addition, this knowledge could contribute to the formulation of functional foods with lower glycemic indexes or improved nutrient delivery. Variations in the complexes can be attributed to differences in molecular weight, structure, and even the content of the polyphenols. In addition, the unique structural characteristics of starches, such as amylose/amylopectin ratio and crystalline density, also contribute to the observed effects. Processing conditions and methods will always alter the formation of complexes. As the type of starch/polyphenol can have a significant impact on the formation of the complex, the selection of suitable botanical sources of starch/polyphenols has become a focus. Spectroscopy coupled with chemometrics is a convenient and accurate method for rapidly identifying starches/polyphenols and screening for the desired botanical source. Understanding these relationships is crucial for optimizing starch-based systems in various applications, from food technology to pharmaceutical formulations.

Optimization of ultrasonic conditions for improving the characteristics of corn starch-glycyrrhiza polysaccharide composite to prepare enhanced quality lycopene inclusion complex

In this study, based on response surface optimization of ultrasound pre-treatment conditions for encapsulating lycopene, the corn starch-glycyrrhiza polysaccharide composite (US-CS-GP) was used to prepare a novel lycopene inclusion complex (US-CS-GP-Lyc). Ultrasound treatment (575 W, 25 kHz) at 35 °C for 25 min significantly enhanced the rheological and starch properties of US-CS-GP, facilitating the preparation of US-CS-GP-Lyc with an encapsulation efficiency of 76.12 ± 1.76 %. In addition, the crystalline structure, thermal properties, and microstructure of the obtained lycopene inclusion complex were significantly improved and showed excellent antioxidant activity and storage stability. The US-CS-GP-Lyc exhibited a V-type crystal structure, enhanced lycopene loading capacity, and reduced crystalline regions due to increased amorphous regions, as well as superior thermal properties, including a lower maximum thermal decomposition rate and a higher maximum decomposition temperature. Furthermore, its smooth surface with dense pores provides enhanced space and protection for lycopene loading. Moreover, the US-CS-GP-Lyc displayed the highest DPPH scavenging rate (92.20 %) and enhanced stability under light and prolonged storage. These findings indicate that ultrasonic pretreatment can boost electrostatic forces and hydrogen bonding between corn starch and glycyrrhiza polysaccharide, enhance composite properties, and improve lycopene encapsulation, which may provide a scientific basis for the application of ultrasound technology in the refined processing of starch-polysaccharides composite products.

Preparation of the black rice starch-gallic acid complexes by ultrasound treatment: Physicochemical properties, multiscale structure, and in vitro digestibility

This study aimed to investigate the multiscale structure, physicochemical properties, and in vitro digestibility of black rice starch (BRS) and gallic acid (GA) complexes prepared using varying ultrasound powers. The findings revealed that ultrasonic treatment disrupted BRS granules while enhancing the composite degree with GA. The starch granules enlarged and aggregated into complexes with uneven surfaces. Moreover, the crystallinity of the BRS-GA complexes increased to 22.73 % and formed V6-I-type complexes through non-covalent bonds. The increased short-range ordering of the complexes and nuclear magnetic resonance hydrogen (1H NMR) further indicated that the BRS and GA molecules interacted mainly through non-covalent bonds such as hydrogen bonds. Additionally, ultrasound reduced the viscoelasticity of the complexes while minimizing the mass loss of the complexes at the same temperature. In vitro digestion results demonstrated an increase in resistant starch content up to 37.60 % for the BRS-GA complexes. Therefore, ultrasound contributes to the formation of V-typed complexes of BRS and GA, which proves the feasibility of using ultrasound alone for the preparation of starch and polyphenol complexes while providing a basis for the multiscale structure and digestibility of polyphenol and starch complexes.

Effect of hawthorn polyphenol extracts on the physicochemical properties and digestibility of corn starch

To investigate the effect of hawthorn polyphenols on the physicochemical properties and digestibility of corn starch, different proportions (1%, 2%, 3%, and 4% [w/w]) of hawthorn polyphenol extracts (HPEs) were mixed with corn starch, and their physicochemical properties and digestive properties were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Rapid Visco Analysis, differential scanning calorimetry, and in vitro/in vivo analysis. Results indicated that small V-type crystal starch tended to be formed in the samples, and the addition of HPEs reduced the viscosity, prolonged the gelatinization temperature of corn starch, and increased the proportion of slowly digestible starch and resistant starch of the corn starch, which accounted for 36.32% ± 1.05% and 33.32% ± 4.07%, respectively. Compared with the raw corn starch, the postprandial blood glucose of mice that were administered the hawthorn polyphenols decreased significantly: the blood glucose peak (30 min) decreased from 14.30 ± 1.52 to 11.77 ± 1.21 mmol/L. Our study might provide some basic theoretical support for the application of hawthorn polyphenols in healthy starchy food processing.

A review of green methods used in starch-polyphenol interactions: physicochemical and digestion aspects

The interactions of starch with lipids, proteins, and other major food components during food processing are inevitable. These interactions could result in the formation of V-type or non-V-type complexes of starch. The starch-lipid complexes have been intensively studied for over five decades, however, the complexes of starch and polyphenols are relatively less studied and are the subject of recent interest. The interactions of starch with polyphenols can affect the physicochemical properties and its digestibility. The literature has highlighted several green methods such as ultrasound, microwave, high pressure, extrusion, ball-milling, cold plasma etc., to assist interactions of starch with polyphenols. However, comprehensive information on green methods to induce starch-polyphenol interactions is still scarce. Therefore, in light of the importance and potential of starch-polyphenol complexes in developing functional foods with low digestion, this review has summarized the novel green methods employed in interactions of starch with flavonoids, phenolic acids and tannins. It has been speculated that flavonoids, phenolic acids, and tannins, among other types of polyphenols, may have anti-digestive activities and are also revealed for their interaction with starch to form either an inclusion or non-inclusion complex. Further information on the effects of these interactions on physicochemical parameters to understand the chemistry and structure of the complexes is also provided.

Effects of ultrasound-induced V-type rice starch-tannic acid interactions on starch in vitro digestion and multiscale structural properties

V-type starch-polyphenol complexes, known for their improved physicochemical properties compared to native starch, are challenging to form efficiently. In this study, the effects of tannic acid (TA) interaction with native rice starch (NS) on digestion and physicochemical properties were investigated using non-thermal ultrasound treatment (UT). Results showed the highest complexing index for NSTA-UT3 (∼ 0.882) compared to NSTA-PM (∼0.618). NSTA-UT complexes reflected the V6I-type complex having six anhydrous glucose per unit per turn with peaks at 2θ = 7°, 13°, and 20°. The maxima of the absorption for iodine binding were suppressed by the formation of V-type complexes depending on the concentration of TA in the complex. Furthermore, rheology and particle size distributions were also affected by TA introduction under ultrasound, as revealed by SEM. XRD, FT-IR, and TGA analyses confirmed V-type complex formation for NSTA-UT samples, with improved thermal stability and increased short-range ordered structure. Ultrasound-induced addition of TA also decreased the hydrolysis rate and increased resistant starch (RS) concentration. Overall, ultrasound processing promoted the formation of V-type NSTA complexes, suggesting that tannic acid could be utilized for the production of anti-digestion starchy foods in the future.

Starches modification with rose polyphenols under multi-frequency power ultrasonic fields: Effect on physicochemical properties and digestion behavior

As the main source of energy for human beings, starch is widely present in people's daily diet. However, due to its high content of rapidly digestive starch, it can cause a rapid increase in blood glucose after consumption, which is harmful to the human body. In the current study, the complexes made from edible rose polyphenols (ERPs) and three starches (corn, potato and pea) with different typical crystalline were prepared separately by multi-frequency power ultrasound (MFPU). The MFPU includes single-frequency modes of 40, 60 kHz and dual-frequency of 40 and 60 kHz in sequential and simultaneous mode. The results of the amount of complexes showed that ultrasound could promote the formation of polyphenol-starch complexes for all the three starches and the amount of ERPs in complexes depended on the ultrasonic parameters including treatment power, time and frequency. Infrared spectroscopy and X-ray diffraction indicated that ERPs with or without ultrasound could interact with the three starches through non-covalent bonds to form non-V-type complexes. Scanning electron microscopy showed that the shape of starches changed obviously from round/oval to angular and the surface of the starches were no longer smooth and appeared obvious pits, indicating that the ultrasonic field destroyed the structure of starches. In addition, compared to the control group, the in vitro digestibility study with 40/60 kHz sonication revealed that ultrasonic treatment greatly improved the digestive properties of the polyphenol-starch complexes by significantly increasing the content of resistant starch (20.31%, 17.27% and 14.98%) in the three starches. Furthermore, the viscosity properties of the three starches were all decreased after ERPs addition and the effect was enhanced by ultrasound both for single- and dual-frequency. In conclusion, ultrasound can be used as an effective method for preparing ERPs-starch complexes to develop high value-added products and low glycemic index (GI) foods.

Synergistic impact of heat-ultrasound treatment on the properties and digestibility of Sagittaria sagittifolia L. starch-phenolic acid complexes

The current research investigated the multi-scale structural interactions between arrowhead starch (AS) and phenolic acids, such as ferulic acid (FA) and gallic acid (GA) to identify the mechanism of anti-digestion effects of starch. AS suspensions containing 10 % (w/w) GA or FA were subjected to physical mixing (PM) followed by heat treatment at 70 °C for 20 min (HT) and a synergistic heat-ultrasound treatment (HUT) for 20 min using a dual-frequency 20/40 KHz system. The synergistic HUT significantly (p < 0.05) increased the dispersion of phenolic acids in the amylose cavity, with GA showing a higher complexation index than FA. XRD analysis showed a typical V-type pattern for GA, indicating the formation of an inclusion complex, while peak intensities decreased for FA following HT and HUT. FTIR revealed sharper peaks possibly of amide bands in the ASGA-HUT sample compared to that of ASFA-HUT. Additionally, the emergence of cracks, fissures, and ruptures was more pronounced in the HUT-treated GA and FA complexes. Raman spectroscopy provided further insight into the structural attributes and compositional changes within the sample matrix. The synergistic application of HUT led to increased particle size in the form of complex aggregates, ultimately improving the digestion resistance of the starch-phenolic acid complexes.

The Fluorescence Response of Four Crystalline Starches According to Ultrasound-Assisted Starch-Salicylic Acid Inclusions

Fluorescence has shown its superior performance in the fields of starch physicochemical properties, starch–based materials, and the interactions of starch with small molecules. However, it has not been well explored in the fluorescence characteristics of starch. Herein, the fluorescence properties of four crystalline starches (A–type tapioca starch, B–type potato starch, C–type pea starch, and V–type starch, prepared with corn starch and stearic acid) were investigated using salicylic acid (SA) as an indicator. The results of inverted fluorescence microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis indicated that SA could be included by starch. X–ray diffraction analysis further demonstrated that the inclusion of SA did not change the crystalline of the four crystal types of starches, which could provide a prerequisite for comparing the different fluorescence properties of the four crystal types of starches. Fluorescence enhancements of the four inclusions were 264.5 (B–type), 206 (C–type), 51.2 (V–type), and 28 (A–type). These results provide new insights for analyzing the fluorescence response of starch.

Starches in the encapsulation of plant active ingredients: state of the art and research trends

As a natural polymer, starches and their derivatives have received widespread attention in the cosmetic and pharmaceutical industries, particularly for their use as a coating material. In this sense, as an encapsulating agent, starches stand out, considering the number of compounds that they can trap. Additionally, they provide a nutritional contribution and may improve acceptance by patients. As such, this type of material may serve as an alternative to overcome gaps such as loss of activity of the active principles, low assimilation, or deterioration under environmental and physiological conditions. In this paper, we aim to present the state of the art and research trends on the use of starch as a wall material for the encapsulation of active principles of plant origin. It was found that the most-encapsulated active principles are essential oils and polyphenols; native or modified starches are typically used, either as the sole wall material or in combination with other polymers; and the most widely used methodology is spray drying. The reviewed studies indicate the potential of starches for their use in active ingredient encapsulation processes, improving their viability and expanding their range of applications in different industries, as well as showing a clearly increasing publication trend over the last 10 years.

Graphical abstract

Physicochemical properties and digestion mechanism of starch-linoleic acid complex induced by multi-frequency power ultrasound

The effects of multi-frequencies (mono: 20 kHz, 40 kHz, 60 kHz; dual: 20/40 kHz, 40/60 kHz, 20/60 kHz, and tri: 20/40/60 kHz) on physicochemical properties and in vitro digestibility of arrowhead starch-linoleic acid (AS-LA) complexes were evaluated. The complexing index and FTIR analyses showed that sonication treatment might be helpful in the formation of AS-LA complexes in an ultrasound frequency-dependent manner. The SEM micrographs revealed that the various ultrasonication frequencies caused dense network structure in AS-LA complexes. The XRD showed a V-type crystalline structure with increased crystallinity. Compared with arrowhead starch, a decrease in rapidly digestible starch , and an increase in resistant starch contents of AS-LA under various ultrasound frequencies was due to arrowhead starch and linoleic acid molecular interactions, which inhibited the further binding abilities. As a non-thermal technology, ultrasound could be effectively employed to prepare starch-lipid complexes with significant potential in functional foods and drug delivery systems.