Physicochemical properties and in vitro digestibility of sorghum starch altered by high hydrostatic pressure

Impacts of transglutaminase on the processing and digestion characteristics of glutinous rice flour: Insight of the interactions between enzymic crossing-linked protein and starch

Glutinous rice is extensively consumed due to its nutritious content and wonderful flavor. However, glutinous rice flour has a high glycemic index, and the storage deterioration of sweet dumplingsissevere. Transglutaminase (TG) was used to cross-link glutinous rice protein and improve the characteristics of glutinous rice products. The findings demonstrated that TG significantly catalysed protein cross-linking to form a dense protein network, reduced the viscosity of glutinous rice paste and improved the thermal stability. The protein network may physically block the access of starch granules to digestive enzymes to lower the digestion rate of starch, and attenuate the damage of ice crystal molecules to the starch structure to improve the freezing stability of starch gels. The cracking rate and water loss of sweet dumplings prepared using glutinous rice flour with TG treated for 60 min reduced significantly. In conclusion, this study broadened the application of TG in starch products.

Structural, physicochemical and functional properties of high-pressure modified white finger millet starch

The effect of high-pressure processing (HPP) modification (200, 400, and 600 MPa for 10 min) on the physico-chemical, functional, structural, and rheological properties of white finger millet starch (WFMS) was studied. Measured amylose content, water, and oil absorption capacity, alkaline water retention, and pasting temperature increased significantly with the intensity of pressure. All color parameters (L, a, b values, and ΔC) were affected by HPP treatment, and paste clarity of modified starch decreased significantly with an increase in storage time. The samples' least gelation concentration (LGC) is in the range of 8-14 %. An increasing solubility and swelling power are noted, further intensifying at the elevated temperature (90 °C). The structural changes of WFMS were characterized by XRD, SEM, and FTIR spectroscopy. Starch modified at 600 MPa showed a similar pattern as 'B'-type crystalline, and the surfaces of starch deformed because of the gelatinization. Applied pressure of 600 MPa affected the FTIR characteristic bands at 3330, 2358, and 997 cm-1, indicating a lower crystallinity of the HPP-600 modified sample. According to DSC analysis, even at 600 MPa, WFMS is only partially gelatinized. This work provides insights for producing modified WFM starches by a novel physical modification method.

Physicochemical properties of amorphous granular starch (AGS) prepared by non-thermal gelatinization by high hydrostatic pressure (HHP) and spray drying

Corn starch was gelatinized by high hydrostatic pressure (HHP) and spray drying to make amorphous granular starch (AGS), and their physicochemical properties were compared with the conventionally prepared (heat-gelatinized and spray dried) AGS to devise a novel AGS preparation methodology. Pressure-induced (PAGS) and heat-induced AGS (HAGS) maintained their granular shape but lost their birefringence indicating that both methods could prepare AGS. DSC (differential scanning calorimeter) and XRD (X-ray diffraction) analysis confirmed the complete loss of amylopectin double helices and crystallinity of both PAGS and HAGS. However, their swelling power, solubility, RVA pasting properties, acid/shear stability, gel forming ability and textural properties were completely different. PAGS exhibited constrained swelling, suppressed amylose leaching, and reduced viscosity. Notably, HAGS formed a gel without heating, whereas PAGS yielded a viscous paste with water-soluble attributes. Even after reheating, PAGS maintained its granular structure with comparably less swelling and weaker gel strength than HAGS. Consequently, newly developed PAGS exhibited distinctive characteristics compared to the conventional HAGS, such as lower solubility and swelling power, viscosity, textural properties, and high acid and shear stabilities, rendering it a viable option for various applications within the food industry.

Molecular morphology & interactions, functional properties, rheology and in vitro digestibility of ultrasonically modified pearl millet and sorghum starches

The present research investigated to study the effect of ultrasound treatment on isolated pearl millet starch (PMS) and sorghum starch (SS). Ultrasonication was applied to PMS and SS for 10, 15, and 20 min. Ultrasonically modified pearl millet and sorghum starches evaluated for their techno-functionality, pasting profile, morphology, in vitro starch digestibility, XRD, and molecular interactions. Ultrasound treatment increased water and oil absorption capacity, swelling power, and solubility with treatment time. For ultrasonicated PMS and SS, a significant increase (p < 0.05) in paste clarity (PC) (70.05 % and 67.23 %), freeze-thawing stability (FTS), gel consistency (GC) (25.05 mm and 32.95 mm), and in vitro starch digestibility were observed (57.70 g/100 g and 50.29 g/100 g), whereas no significant changes were recorded for the color values after the ultrasound treatment. Variations in pasting property were also observed in ultrasonicated starches with treatment duration. SEM images confirmed ultrasonication mainly forms pores and indentations on starch granule surface. FTIR spectra and X-ray diffractogram for ultrasonicated starches revealed a slight decrease in the peak intensity and A-type X-ray pattern with lower relative crystallinity (RC) than the native starches. G' > G″ value, indicating the elastic behavior and lower tan δ value, depicting viscous behavior and high gel strength.

A review of starch swelling behavior: Its mechanism, determination methods, influencing factors, and influence on food quality

Swelling behavior involves the process of starch granules absorbing enough water to swell and increase the viscosity of starch suspension under hydrothermal conditions, making it one of the important aspects in starch research. The changes that starch granules undergo during the swelling process are important factors in predicting their functional properties in food processing. However, the factors that affect starch swelling and how swelling, in turn, affects the texture and digestion characteristics of starch-based foods have not been systematically summarized. Compared to its long chains, the short chains of amylose easily interact with amylopectin chains to inhibit starch swelling. Generally, reducing the swelling of starch could increase the strength of the gel while limiting the accessibility of digestive enzymes to starch chains, resulting in a reduction in starch digestibility. This article aims to conduct a comprehensive review of the mechanism of starch swelling, its influencing factors, and the relationship between swelling and the pasting, gelling, and digestion characteristics of starch. The role of starch swelling in the edible quality and nutritional characteristics of starch-based foods is also discussed, and future research directions for starch swelling are proposed.

The effect of non-thermal physical modification on the structure, properties and chemical activity of starch: A review

Non-thermal physical treatments has obvious advantages in regulating the structure and properties of starch compared with chemical treatment. Hance, this article summarized and compared the effects of three kinds of non-thermal physical treatments including grinding and ball milling, high hydrostatic pressure and ultrasonic on the structure, properties and chemical activity of starches from different plants. The potential applications of non-thermal physical modified starch were introduced. And strategies to solve the problems in the current research were put forward. It is found that although starch has a dense structure, the starch granules could be deformed under three kinds of non-thermal physical treatments, which could damage the granule morphology, microstructure, and crystal structure of starch, reduce particle size, increase solubility and swelling power, and promote starch gelatinization. Three kinds of non-thermal physical treated starch could be used as flocculant thickener, starch based edible films and fat substitutes. Non-thermal physical treatments caused the structure of starch to undergo three stages, which were similar to mechanochemical effects. When starch was in the stress stage and the transition stage from aggregation to agglomeration, its active sites significantly increase and move inward, ultimately leading to a significant increase in the chemical activity of starch.

Native and modified starches from underutilized seeds: Characteristics, functional properties and potential applications

Seeds represent a potential source of starch, containing at least 60-70% of total starch, however many of them are treated as waste and are usually discarded. The review aim was to analyze the characteristics, functional properties, and potential applications of native and modified starches from underutilized seeds such as Sorghum bicolor L. Moench (WSS), Chenopodium quinoa, Wild. (QSS), Mangifera indica L. (MSS), Persea americana Mill. (ASS), Pouteria campechiana (Kunth) Baehni (PCSS), and Brosimum alicastrum Sw. (RSS). A systematic review of scientific literature was carried out from 2014 to date. Starch from seeds had yields above 30%. ASS had the higher amylose content and ASS and RSS showed the highest values in water absorption capacity and swelling power, contrary to MSS and PCSS while higher thermal resistance, paste stability, and a lower tendency to retrograde were observed in MSS and RSS. Functional properties such as water solubility, swelling power, thermal stability, low retrogradation tendency, and emulsion stability were increased in RSS, WSS, QSS, and MSS with chemical modifications (Oxidation, Oxidation-Crosslinking, OSA, DDSA, and NSA) and physical methods (HMT and dry-heat). Digestibility in vitro showed that WSS and QSS presented high SDS fraction, while ASS, MSS, PCSS, and HMT-QSS presented the highest RS content. Native or modified underutilized seed starches represent an alternative and sustainable source of non-conventional starch with potential applications in the food industry and for the development of healthy foods or for special nutritional requirements.

The effects of high-pressure treatment on the structure, physicochemical properties and digestive property of starch - A review

High hydrostatic pressure (HHP) is a novel technology used in the food-processing industry. Starch is an important renewable natural resource. The applications of starch are determined by its properties, which in turn are determined by its structure. In this study, the effects of HHP treatment on starch structure (granular structure, crystalline structure, molecular structure, and molecular conformation) and properties (pasting, retrogradation, thermal, digestive, rheological, swelling, solubility, water absorption, and oil absorption properties) are summarised. Additionally, the mechanism of HHP-induced gelatinisation is discussed. First, the strong hydration ability of starch molecules under high pressure facilitates the binding of water molecules to starch molecules via hydrogen bonding. These bound water molecules may block the channels inside the starch granules, leading to the formation of a sealed space. Finally, the granules disintegrate because of the intra/extra pressure difference. This study provides a reference for the application of HHP to starch processing and modification.

Characteristics of physically modified starches

Starch is an abundant natural, non-toxic, biodegradable polymer. Due to its low price, it is used for various purposes in various fields such as the cosmetic, paper, and construction industries as well as the food industry. Due to recent consumer interest in clean label materials, physically modified starch is attracting attention. Manufacturing methods of physically modified starch include pregelatinization, hydrothermal treatment such as heat moisture treatment and annealing, hydrostatic pressure treatment, ultrasonic treatment, milling, and freezing. In this study, toward development of clean label materials, manufacturing methods and characteristics of physically modified starches were discussed.

Dry heating affects the multi-structures, physicochemical properties, and in vitro digestibility of blue highland barley starch

As a physical method for starch modification, dry heating treatment (DHT) at high temperatures (150 and 180°C, respectively) was applied to blue highland barley (BH) starch with different durations (2 and 4 h). The effects on its multi-structures, physicochemical properties, and in vitro digestibility were investigated. The results showed that DHT had changed the morphology of BH starch, and the diffraction pattern remained an "A"-type crystalline structure. However, with an extension of DHT temperature and time, the amylose content, gelatinization temperature, enthalpy value, swelling power, and pasting viscosity of modified starches decreased, while the light transmittance, solubility, and water and oil absorption capacities increased. Additionally, compared with native starch, the content of rapidly digestible starch in modified samples increased after DHT, whereas those of slowly digestible starch and RS decreased. Based on these results, the conclusion could be drawn that DHT is an effective and green way to transform multi-structures, physicochemical properties, and in vitro digestibility of BH starch. This fundamental information might be meaningful to enrich the theoretical basis of physical modification on BH starch and extend the applications of BH in the food industry.

A study on the structural, physicochemical, rheological and thermal properties of high hydrostatic pressurized pearl millet starch

Starch in native form has limited application due to functional and physicochemical characteristics. To overcome these limitations, starch can be modified by non-thermal technologies such as high hydrostatic pressure (HHP). This study investigates high-pressure-induced gelatinization and the effect of this process on the structural, functional, morphological, pasting, thermal, physical and rheological properties of millet starch. The suspension of millet starch and water was pressurized at 200, 400 and 600 MPa for 10, 20 and 30 min to modify the starch in terms of structure, morphology, some physicochemical and rheological properties. Swelling strength and starch solubility decreased as a result of treatment with HHP. All treatments caused to increase in water holding capacity of the starch (from 0.66 % for native starch to 2.19 % for 600 MPa-30 min). Thermal analysis showed a decrease in gelatinization temperature and enthalpy of gelatinization and the pasting properties showed a decrease in the peak viscosity after HHP treatment. In addition, HHP treatment caused to increase in the hydration ability of starch by creating porosity and gaps in the granule surface and increasing the specific surface area. HHP application resulted in an increase in the peak time and pasting temperature and a decrease in breakdown and peak viscosities, final viscosity and setback viscosity in comparison with native starch of millet. The starch sample treated with 600 MPa for 30 min had the lowest syneresis and retrogradation ability. Increasing pressure and the time led to an increase in the elastic nature of the starch samples. According to the results, it is possible to increase usage area of starches in the food industry by improving its technological with HHP. This green physical technology can influence the quality parameters of starch, which can provide benefits for product machining and economic purposes.

Nonthermal physical modification of starch: An overview of recent research into structure and property alterations

To tailor the properties and enhance the applicability of starch, various ways of starch modification have been practiced. Among them, physical modification methods (micronization, nonthermal plasma, high-pressure, ultrasonication, pulsed electric field, and γ-irradiation) are highly potential for starch modification considering its safety, environmentally friendliness, and cost-effectiveness, without generating chemical wastes. Thus, this article provides an overview of the recent advances in nonthermal physical modification of starch and summarizes the resulting changes in the multi-level structures and physicochemical properties. While the effect of these techniques highly depends on starch type and treatment condition, they generally lead to the destruction of starch granules, the degradation of molecules, decreases in crystallinity, gelatinization temperatures, and viscosity, increases in solubility and swelling power, and an increase or decrease in digestibility, to different extents. The advantages and shortcomings of these techniques in starch processing are compared, and the knowledge gap in this area is commented on.

Comparative effects of high pressure processing and heat treatment on in vitro digestibility of pea protein and starch

The effects of high-pressure processing (HPP) and heat treatment on the digestibility of protein and starch in pea protein concentrate (PPC) were investigated. Samples of PPC with 5% (5 P) and 15% (15 P) protein were treated by HPP (600 MPa/5 °C/4 min) or heat (95 °C/15 min) and their in vitro static and dynamic digestibility were compared to untreated controls. HPP-treated PPC underwent a greater degree of proteolysis and showed different peptide patterns after static gastric digestion compared to untreated and heat-treated PPC. Differences in protein digestibility among treatments during dynamic digestion were only significant (p < 0.05) during the first 20 min of jejunal, ileal, and total digestion for 5 P, and during the first 60 min of ileal digestion for 15 P. Neither static nor dynamic starch digestibility were dependent on treatment. HPP did not reduce trypsin inhibitor activity, whereas heat treatment reduced it by ~70%. HPP-induced structural modifications of proteins and starch did not affect their overall in vitro digestibility but enhanced gastric proteolysis.

A highly efficient nanoscale tapioca starch prepared by high-speed jet for Cu2+ removal in simulated industrial effluent

BACKGROUND

Nanoscale tapioca starch (NTS) was successfully developed by high-speed jet in our previous study. In this study, the adsorption capacity of Cu²⁺ onto NTS was further discussed. The optimal adsorption conditions (pH, contact time, contact temperature, initial Cu²⁺ concentration, and adsorbent concentration), adsorption kinetics, isotherms, and thermodynamic were also evaluated.

RESULTS

The results showed that NTS exhibited excellent performance in adsorption of Cu²⁺ , with adsorption capacities of 122.31 mg g^-1 for Cu²⁺ (pH 7, 0.04 g L^-1 , 0.2 g L^-1 , 313.15 K and 10 min). The pseudo-second-order and Langmuir isotherms models could be used to explain the adsorption kinetics and adsorption equilibrium, respectively. The thermodynamic results showed that the adsorption process was spontaneous and endothermic with an increase in entropy. Cu²⁺ was adsorbed onto NTS, which was confirmed by energy dispersive spectrometry analysis.

CONCLUSION

These findings indicated that NTS might be an effective, environment-friendly and renewable bio-resource adsorbent for removing heavy metals in industrial effluent. © 2021 Society of Chemical Industry.

Impact of thermo-sonication on quality indices of starch-based sauces

In this study, ultrasonication, a physical, relatively cheap, and environmentally benign technology, was investigated to characterize its effect on functional properties of rice starch and rice starch-based sauces. Temperature-assisted ultrasound treatment improved the granular swelling power, fat and water absorption capacities, and thermal properties of rice starch, signifying its suitability in the formulation of starch-based sauces. Rheological characterization of the formulated sauces revealed a shear-thinning flow behavior, well described by the Ostwald de Waele model, while viscoelastic properties showed the existence of a weak gel. Results indicated that ultrasonication significantly enhanced the pseudoplastic behavior of starch-based sauces. Additionally, textural analysis showed that textural attributes (stickiness, stringiness, and work of adhesion) were also improved with ultrasonication. Moreover, enhanced freeze/thaw stability was also achieved with ultrasound-treated starch-based sauces. Overall, the results from this study show that ultrasound-treated starches can be used in the formulation of sauces and potentially other food products, which meets the requirements for clean label and minimally processed foods.

Effects of ultra-high pressure on the morphological and physicochemical properties of lily starch

In this study, starch extracted from lily bulbs were modified using an ultra-high pressure (UHP) treatment at six different pressure levels (100, 200, 300, 400, 500, and 600 MPa). The effects of UHP treatment on the physicochemical and morphological properties of lily starch were investigated. The morphological observation revealed that UHP treatment led to particle expansion and aggregation. Compared with the native and lily starch treated at 100-500 MPa, the lily starch treated at 600 MPa exhibited almost completely disrupted morphology and a larger particle size, indicating nearly complete gelatinization of the starch. The relative crystallinity of the UHP-treated starch remarkably reduced. Gelatinization temperatures via differential scanning calorimetry decreased with increasing pressure. The rapid viscoanalyzer results revealed that the lily starch treated with UHP at 600 MPa showed low values of peak viscosity, trough viscosity, breakdown, final viscosity, and setback. These results indicated that UHP was an effective physical modification method for lily starch, UHP treatment (600 MPa, 30 min) caused nearly complete gelatinization of lily starch, and lily starch modified using UHP might expand the application of lily in the food field.

Modifying Effects of Physical Processes on Starch and Dietary Fiber Content of Foodstuffs

Carbohydrates are one of the most important nutrients in human consumption. The digestible part of carbohydrates has a significant role in maintaining the energy status of the body and the non-digestible parts like dietary fibers have specific nutritional functions. One of the key issues of food processing is how to influence the technological and nutritional properties of carbohydrates to meet modern dietary requirements more effectively, considering particularly the trends in the behavior of people and food-related health issues. Physical processing methods have several advantages compared to the chemical methods, where chemical reagents, such as acids or enzymes, are used for the modification of components. Furthermore, in most cases, these is no need to apply them supplementarily in the technology, only a moderate modification of current technology can result in significant changes in dietary properties. This review summarizes the novel results about the nutritional and technological effects of physical food processing influencing the starch and dietary fiber content of plant-derived foodstuffs.

Microbial Shelf-Life, Starch Physicochemical Properties, and in Vitro Digestibility of Pigeon Pea Milk Altered by High Pressure Processing

This study examined the effects of high-pressure processing (HPP) on microbial shelf-life, starch contents, and starch gelatinization characteristics of pigeon pea milk. HPP at 200 MPa/240 s, 400 MPa/210 s, and 600 MPa/150 s reduced the count of Escherichia coli O157:H7 in pigeon pea milk by more than 5 log CFU/mL. During the subsequent 21-day refrigerated storage period, the same level of microbial safety was achieved in both HPP-treated and high-temperature short-time (HTST)-pasteurized pigeon pea milk. Differential scanning calorimetry and scanning electron microscope revealed that HPP at 600 MPa and HTST caused a higher degree of gelatinization in pigeon pea milk, with enthalpy of gelatinization (∆H) being undetectable for both treatments. In contrast, HPP at 400 MPa led to an increase in the onset temperature, peak temperature, and conclusion temperature, and a decrease in ∆H, with gelatinization percentages only reaching 18.4%. Results of an in vitro digestibility experiment indicate that maximum resistant starch and slowly digestible starch contents as well as a decreased glycemic index were achieved with HPP at 400 MPa. These results demonstrate that HPP not only prolongs the shelf-life of pigeon pea milk but also alters the structural characteristics of starches and enhances the nutritional value.

A Review on the Effect of High Pressure Processing (HPP) on Gelatinization and Infusion of Nutrients

High pressure processing (HPP) is a novel technology that involves subjecting foods to high hydrostatic pressures of the order of 100-600 MPa. This technology has been proven successful for inactivation of numerous microorganisms, spores and enzymes in foods, leading to increased shelf life. HPP is not limited to cold pasteurization, but has many other applications. The focus of this paper is to explore other applications of HPP, such as gelatinization, forced water absorption and infusion of nutrients. The use of high pressure in producing cold gelatinizing effects, imparting unique properties to food and improving food quality will be also discussed, highlighting the latest published studies and the innovative methods adopted.

Healthy expectations of high hydrostatic pressure treatment in food processing industry

High hydrostatic pressure processing (HPP) is a non-thermal pasteurization technology which has already been applied in the food industries. Besides maintaining the food safety and quality, HPP also has potential applications in the enhancement of the health benefits of food products. This study examines the current progress of research on the use of HPP in the development of health foods. Through HPP, the nutritional value of food products can be enhanced or retained, including promotes the biosynthesis of γ-aminobutyric acid (GABA) in the food materials, retains immunoglobulin components in dairy products, increases resistant starch content in cereals, and reduces the glycemic index of fruit and vegetable products, which facilitates better control of blood glucose levels and decreases calorie intake. HPP can also be utilized as a hurdle technology in combination with existing processing technologies for the development of low-sodium food products and the maintenance of microbial safety, thereby lowering the risk of triggering cardiovascular disease. Additionally, HPP can be used to enhance the diversity of probiotic food products. Appropriate sporogenous probiotics can be screened and added to various high-pressure processed food products as a certain bacterial count is still retained in the products after HPP. As HPP causes physical damage to the structures of food products, it can also be used as a synergistic extraction technology to enhance the extraction efficiency of functional components, thereby reducing extraction time. By applying HPP in the extraction of functional components from food waste, the production costs of such components can be effectively reduced. This study provides a summary of the mechanisms by which HPP enhances the health benefits of food products and the current progress of relevant research. HPP possesses huge potential in the development of novel health foods and may provide an abundance of benefits to human health in the future.

C-type starches and their derivatives: structure and function

The C-type starches are widely distributed in seeds or rhizomes of various legumes, medicinal plants, and crops. These carbohydrate polymers directly affect the application of starchy plant resources. The structural and crystal properties of starches are crucial parameters of starch granules, which significantly influence their physicochemical and mechanical properties. The unique crystal structure consisting of both A- and B-type polymorphs endows C-type starches with specific crystal adjustability. Furthermore, large proportions of resistant starches and slowly digestible starches are C-type starches, which contribute to benign glycemic response and proliferation of gut microflora. Here, we review the distribution of C-type starches in various plant sources, the structural models and crystal properties of C-type starches, and the behavior and functionality relevant to modified C-type starches. We outline recent advances, potential applications, and limitations of C-type starches in industry, aiming to provide a theoretical basis for further research and to broaden the prospects of its applications.