Impact Of Heat-moisture Treatment Research Articles

Impact of Heat Moisture Treatment and Pregelatinization of Corn Starch on the Functional and Nutritional Properties of Breads Supplemented with Corn Germ

Properties of modified starch are of great interest to the bakery industry. Moreover, corn germ incorporation in bread has multiple health benefits. The aim of this study was the formulation of Brotchen bread with corn germ flour (0, 10, 20, and 30% w/w) and modified corn starch (0, 10, 20, and 30% w/w). The effect of heat‐moisture treatment (HMT) and pregelatinization (PG) of starch was investigated on the rheological and physicochemical properties of bread. The addition of corn germ flour and modified starch increased some farinograph properties, i.e., water absorption, consistency, and dough development time, and decreased dough stability. The degree of softening of the dough increased after 12 min after supplementation. The farinograph quality number in the dough containing HMT was the highest value. By replacing corn germ flour and modified starch, extensograph parameters such as dough resistance were strengthened and dough extensibility was weakened. Also, the energy of the dough increased. The highest fat, protein, fiber, and moisture content was observed in the treatment containing 30% corn germ flour and HMT starch (HMT3). Also, the HMT3 treatment had the highest specific volume and porosity and the lowest weight loss and hardness (p < 0.05). Regarding the color parameters, HMT3 treatment showed the highest lightness (L∗) and the lowest yellowness (b∗). Enriched bread by corn germ had more iron, calcium, potassium, magnesium, and phosphorus compared to wheat bread. Regarding overall acceptability, no significant difference was observed between treated and untreated bread (p > 0.05). Therefore, the corn germ flour and modified starch in the formulation of bread improved the functional and nutritional properties of bread and can be used in the bread formulation especially at a concentration of 30%.

The impact of heat moisture treatment on the physicochemical properties and in vitro glycemic index of rice flour with different amylose contents and associated effects on rice dumpling quality

This study investigated the effects of heat moisture treatment (HMT) on the in vitro glycemic index and physicochemical properties of rice flour from two cultivars with different amylose contents. HMT decreased glycemic index and pasting viscosity, but increased pasting temperature and onset temperature relative to non-treated rice flour. High-amylose rice flour exhibited significantly higher pasting temperature and lower glycemic index than that with low amylose content. Rice flour dumplings prepared with 0, 40, 50, or 60% w/w HMT flour demonstrated differing texture profiles and sensory characteristics. Pearson's correlation showed that the amylose content of the rice flour used to make the dumplings was positively correlated (p < 0.01) with their hardness and negatively correlated (p < 0.01) with their adhesiveness, cohesiveness, and overall acceptance score. In addition, the glycemic index decreased with increasing HMT flour proportion. It was therefore concluded that HMT of rice flour could be used to achieve product acceptance with a lower glycemic index by compromising between physicochemical properties and sensory quality.

Structuring Diluted Wheat Matrices: Impact of Heat-Moisture Treatment on Protein Aggregation and Viscoelasticity of Hydrated Composite Flours

The influence of heat-moisture treatment (HMT) and flour hydration (DY) on the restoration of dough viscoelasticity of wheat/non-wheat binary matrices was investigated by applying fundamental and empirical rheological procedures, and the protein structural reorganization was monitored by measuring residual protein solubility in different media, and by assessing the accessibility of thiol groups inside the protein network. Single chestnut (CN), chickpea (CP), millet (MI), and teff (T) flour samples submitted to HMT (15% moisture content, 1 h and 120 °C) were blended with wheat flour at 10% (CN, CP) and 30% (MI, T) of replacement, and binary matrices hydrated at low (L), medium (M), and high (H) DY. Structuring ability of HMT was mainly observed in cereal flour blends (T, MI), where higher elastic moduli and lower loss tangent together with solid-like elastic structure over higher shear stress were observed as compared with treated non-cereal flour blends (CN, CP). Increased flour hydration significantly weakened blends structure, inducing a stepped decrease in dynamic moduli values particularly noticed in cereal blends at highest level of flour hydration, and a shift from elastic-like to viscous-like structure at lower shear stress in non-wheat cereal matrices. The formation of a protein network with reinforced compact structure associated to the presence or formation of intramolecular (CN, CP, T) and intermolecular disulphide bonds (CN, CP, MI, T), water-soluble (CN, MI) and water-insoluble aggregates (CP, T) is feasible to achieve with proteins of non-wheat flours submitted to HMT, particularly in high DY doughs. The lower the amount of free thiols in high molecular weight proteins encompassing high degree of crosslinking, corresponded to thermally treated samples (T, MI) blended at L and M hydration levels. For thermally treated samples, the lower the amount of free thiols in high molecular weight proteins encompassing high degree of crosslinking, corresponded to T and MI binary matrices blended at L and M hydration levels. These samples exhibited a solid-like elastic structure over higher shear stress and showed increased tolerance to stress/strain before losing the structure.

Impact of Heat Moisture Treatment and Hydration Level of Flours on the Functional and Nutritional Value-Added Wheat-Barley Blended Breads

The impact of heat moisture treatment (HMT) of flours on the techno-functional and nutritional patterns of binary flour bread matrices (wheat/barley, WT/CB, 60:40, w/w) was investigated in untreated (−) and HMT (+) samples made at 160 and 170 dough yield (DY) levels. Assessment was performed by determining viscoelastic (stress relaxation test) and mechanical (double compression test) behaviours, volume (seed displacement), colour (Photoshop system), crumb grain (digital image analysis), starch digestibility (enzyme hydrolysis) and staling kinetics (Avrami equation), bioaccessible polyphenol content (digestive enzymatic mild extraction) and anti-radical activity (DPPH●). A superior functional profile was provided by HMT of CB flour in the blend WT−CB+ when hydrated at DY 170 compared to the untreated control WT−CB−. The sample exhibited a similar specific volume, more cohesive, springier, more resilient crumb, with similar rate and extent of crumb firming on ageing, and similar colour pattern but finer and more uniformly sized cell structure, and deserved similar sensory ratings as the control WT−CB− concerning cell uniformity, smoothness and typical smell and taste. Digestible starch kinetic curves of blended breads pointed out samples WT−CB+ and WT+CB+ as matrices expliciting a lower degree and slower rate of starch hydrolysis when mixed at low and high DY, respectively. A similar anti-radical activity for composite bread matrices was evidenced regardless of either HMT or DY.

The Impact of Heat-Moisture Treatment on the Properties of Musa paradisiaca L. Starch and Optimization of Process Variables.

SUMMARYStarch stability under the processing conditions can be improved by modifying the granule structure using chemical and/or physical processes. The effect of heat-moisture treatment (HMT) on the physicochemical, morphological, pasting and thermal properties of green banana (Musa paradisiaca L.) starch was investigated. To analyze the changes in starch properties due to the combined effect of the process variables, time (h), moisture (%), and temperature (°C) were considered as independent variables using a central composite rotatable design. The native starch extracted using ammonium hydroxide as an antioxidant contained 80.4% total carbohydrates, 53.7% apparent amylose, 11.46% moisture, and other constituents (ash, protein, lipids), which accounted for less than 1%. The granule morphology was affected by the moisture and temperature used in HMT. A and B type X-ray diffraction patterns were observed in the native and modified starch. Mathematical models that describe the behaviour of modified starch properties as a function of the evaluated parameters were obtained. The variables time and temperature significantly affected the physicochemical, rheological and digestibility properties of starch.

Impact of heat moisture treatment and hydration level on physico-chemical and viscoelastic properties of doughs from wheat-barley composite flours

The impact of heat moisture treatment (HMT) on the thermoviscous, viscoelastic and mechanical properties of binary flour matrices (wheat:barley, 60:40, wt:wt) was investigated in untreated and HMT (15% moisture content, 1 h heating time at 120 °C) hydrated samples to assess the potential of HMT to modify dough viscoelasticity and doughmaking functionality in diluted breadmaking wheat matrices. HMT significance was tackled (a) in excess of water, by applying successive cooking and cooling cycles to hydrated samples (14%, w:w), determination of viscometric parameters, and subsequent determination of textural (compression test) and viscoelastic parameters (stress relaxation test) in pasted and gelled hydrated flours, and (b) under water restrictions by assessing the consistency (forward extrusion test), the primary and secondary mechanical properties (Texture Profile Analysis), and the viscoelastic behaviour (stress relaxation test) of untreated and HMT mixed doughs made at different flour hydration levels (63 and 70%). In highly hydrated blends, HMT barley flour provided enhanced viscosity patterns regardless of the presence of native or HMT wheat flour, and harder gels with larger initial stress to reach a defined deformation, particularly in the presence of HMT wheat flour. Under restricted water availability, doughs made at 70% hydration level when compared to their counterparts made at 63% explicited lower stress relaxation curves with higher values for both initial decay rate and extent of the decay, shorter relaxation times and higher percent of stress relaxation, giving softer and more cohesive doughs. The most elastic-like dough blends were those prepared with HMT wheat and barley flours at 63% hydration, while the most viscous-like doughs were those from native flours made at 70% hydration.

The Impact of Heat-Moisture Treatment on Physicochemical Properties and Retrogradation Behavior of Sweet Potato Starch

Abstract Starch isolated from sweet potato was subjected to different levels of HMT at 15, 20, 25, 30, and 35 %. HMT showed negligible effect on the swelling power of starch. The swelling power was decreased with the increasing of the initial moisture content of the starch. The apparent amylose contents of HMT starches decreased from 24.11 % to 20.56 % with the initial moisture content increasing from 15 % to 35 %. The pasting temperatures enhanced from 73.1 to 81°C (p &lt; 0.05) with the rapidly digestible starch (RDS) contents decreasing from 86.97 to 70.24 % (p &lt; 0.05). Avrami equation analysis showed that HMT reduced the rate of starch retrogradation. The Avrami exponents of native and HMT-35 starches were 0.70 and 0.98 with the recrystallization rates 0.22 and 0.10, respectively. HMT could restrain the starch retrogradation and these results could provide theoretical guidance on sweet potato starch modification.

Optimization of reaction conditions for improving nutritional properties in heat moisture treated maize starch

Impact of heat-moisture treatment (HMT) on nutritional properties of normal maize starch (NMS) under various reaction conditions was investigated. NMS was adjusted to moisture levels of 20%, 25%, 30% and 35% and heated at 80, 100, 120 and 140°C for 4, 8, 12 and 16h. Response surface methodology (RSM) based on Box-Behnken design (BBD) was employed to obtain the optimal combination of moisture level (X1: 20–30%), length of heating (X2: 4–12h), and temperature (X3: 100–140°C). The optimum reaction condition decreased rapidly digestible starch (RDS) from 87.10% to 82.21%, when NMS was subjected to HMT at 23.6% moisture content and heated at 114.8°C for 9.04h. The ANOVA measurement and confirmation experiments were performed to verify the predictive value and the RSM model, indicating that temperature was the main factor to determine the digestion rate of HMT NMS. The results suggested that RDS was not correlated to heating length but positively correlated to temperature and moisture content. Reaction condition had no correlations with slowly digestible starch (SDS) and resistant starch (RS). This study could provide more information for producing low-glycemic index products.

Impact of heat-moisture treatment on rice starch, applied directly in grain paddy rice or in isolated starch

Starch is considered an important ingredient in the preparation of safe food. Current study investigates the physicochemical, morphological, thermal and pasting properties of rice starches, subjected to HMT at 13 g/100 g moisture, at different treatment times (10, 30 and 60 min), directly in the grain paddy rice and in the isolated starch. HMT reduced extraction yield of rice starch with increasing HMT time. The HMT starches had lower gelatinisation enthalpy when compared to native starch. HMT in grain reduced extraction yield of starch by the alkaline method with increasing time of exposure to high temperatures, altering the structure of starch-protein. The HMT in grains decreases the setback of the isolated starches, due to amylose-lipid complexation induced by high temperatures applied on modification. The hydrothermal treatment increased the mechanical and thermal stability of rice starches and promoted the strengthening of links, forming a more stable structure.

The Impact of Heat-Moisture Treatment on Molecular Structures and Properties of Starches Isolated from Different Botanical Sources

Heat-moisture treatment is a hydrothermal treatment that changes the physicochemical properties of starches by facilitating starch chain interactions within the amorphous and crystalline domains and/or by disrupting starch crystallites. The extent of these changes is influenced by starch composition, moisture content and temperature during treatment, and by the organization of amylose and amylopectin chains within native starch granules. During heat-moisture treatment starch granules at low moisture levels [(<35% water (w/w)] are heated at a temperature above the glass transition temperature (T g ) but below the gelatinization temperature for a fixed period of time. Significant progress in heat-moisture treatment has been made during the last 15 years, as reflected by numerous publications on this subject. Therefore, this review summarizes the current knowledge on the impact of heat-moisture treatment on the composition, granule morphology, crystallinity, X-ray pattern, granular swelling, amylose leaching, pasting properties, gelatinization and retrogradation parameters, and susceptibility towards α-amylase and acid hydrolysis. The application of heat-moisture treatment in the food industry is also reviewed. Recommendations for future research are outlined.

The impact of heat-moisture treatment on the molecular structure and physicochemical properties of normal and waxy potato starches

Abstract Normal and waxy potato starches were heat-moisture treated (HMT) at 100 °C for 16 h at a moisture content of 24%. Starch chain interactions, X-ray pattern and intensities, crystallite orientation, molecular order and polymorphic composition changed on HMT. However, birefringence intensity and amylopectin chain length remained unaltered in both starches on HMT. The above structural changes on HMT increased gelatinization temperatures widened the gelatinization temperature range and increased thermal stability in both starches. However, HMT decreased granular swelling, extent of amylose leaching, iodine complexing ability, peak viscosity, extent of set-back, enthalpy of gelatinization, acid susceptibility and the steepness of the adsorption isotherm in both normal and waxy starches. The extent of changes to starch structure and properties on HMT was different in normal and waxy starches due to differences in their amylose content and amylopectin chain mobility.