Extruded Rice Flour Research Articles

Technology for Blending Recombined Flour: Substitution of Extruded Rice Flour, Quantity of Addition, and Impact on Dough.

In a previous study, rice bread was prepared using a combination of rice-wheat mixed flour. To investigate the impact of the partial adoption of extruded rice flour (ERF) on mixed flour (MF) and mixed dough (MD), the effects of adding ERF on the pasting, mixing characteristics, texture, and water retention of the MF and MD were examined by a rapid visco analyzer (RVA), Mixolab, texture profile analysis (TPA), and a low-field nuclear magnetic resonance analyzer (LF-NMR). The PV, TV, BD, FV, and SV of the MF declined as the incorporated amount of ERF increased. There was no significant difference in the PT at the 5-15% addition level (p < 0.05), but it showed an increasing trend at the 20-30% level (p < 0.05). The incorporation of ERF led to a significant increase in the water absorption (WA) of the MD, while the DT, ST, C2, C3, C4, and C5 exhibited a declining trend. The texture analysis revealed a significant decrease in the dough hardness with the addition of ERF, with a 55% reduction in the hardness of the 30% improved mixed dough (IMD), and the cohesiveness increased significantly (p < 0.05). The IMD was mainly composed of weakly bound water. The content of weakly bound water increased with the ERF amount.

Effects of Extrusion Technology on Physicochemical Properties and Microstructure of Rice Starch Added with Soy Protein Isolate and Whey Protein Isolate.

In order to improve the retrogradation of rice starch (RS) and the quality of rice products, soy protein isolate (SPI), whey protein isolate (WPI), and rice flour were mixed and further extruded into mixed flour. The physicochemical properties and morphology of starch of extruded rice flour (ERS) and starch of extruded mixtures of SPI, WPI, and rice flour (SPI-WPI-ERS) were analyzed. The distribution of amylopectin chain length, molecular weight, microstructure, crystallinity, short-range ordered structure, pasting properties, and thermodynamic properties of RS, ERS, and SPI-WPI-ERS were measured. The results showed that, compared with rice starch, the proportion of long-chain starch, total starch content, and molecular weight were decreased in ERS and SPI-WPI-ERS, but the proportion of short-chain and amylose content was increased. The short-range order structure was destroyed. The water absorption of ERS and SPI-WPI-ERS was much higher than rice starch at 55 °C, 65 °C, and 75 °C, but lower than that of rice starch at 95 °C. Therefore, the retrogradation characteristics of SPI-WPI-ERS were improved. The setback of rice starch products was reduced and the setback of SPI-WPI-ERS was lower than that of ERS. Overall, the retrogradation of rice starch was delayed by adding exogenous protein and extrusion technology, and the application range of rice flour in staple food products was broadened.

Insight into the Gluten-Free Dough and Bread Properties Obtained from Extruded Rice Flour: Physicochemical, Mechanical, and Molecular Studies

The present study aimed to evaluate the effect of the extrusion process and particle size on the properties of rice flour (microstructure, pasting properties), gluten-free dough (rheological properties), and bread (texture, specific volume, water absorption capacity, low-field nuclear magnetic resonance (LF NMR) relaxometry). Rice flours were extruded at 80 and 120 °C with feed moisture (15 and 30%) and with the same particle size (&lt;132 and &gt;132–200 µm). Significant differences were observed between the pasting profiles of the flours before and after extrusion. The pasting profile of extruded flours confirmed that hydrothermal treatment partially gelatinized the starch, decreasing the viscosity during heating. The water binding properties increased with the extrusion temperature and moisture content and also with the particle size of the flour. The most important parameter influencing the mechanical properties of the dough was the moisture content of the flour and significant differences were observed between fine (&lt;132 μm) and coarse flours (&gt;132–200 μm). The molecular dynamics of particles containing protons in the bound and bulk fractions in each sample do not depend on the extruder parameters or granulation of the obtained fraction. LF NMR results confirmed that extrusion of rice flour led to a significant decrease in the T21 value compared to the control sample and an increase in the T22 value in breads made with flours with particle size &lt;132 μm. A linear relationship was found between the spin-spin relaxation times (T1) changes and the equilibrium water activity (ar). The results showed that bread with extruded rice flour at the same die temperature resulted in a significantly higher bread volume (31%) and lower hardness (27%) compared to the control. The highest hardness was observed in the case of samples prepared with extruded flour with the addition of 15% moisture, regardless of temperature and particle size.

Physicochemical and structural properties and digestibility of rice flour with different moisture extrusion cooking

SummaryExtruded rice flour with different feed moisture content (FMC, 14%, 16%, 18%, 20%, 22%) were obtained by a twin‐screw with two co‐rotating screws of 65 mm diameter at 120 kg h−1 feed rate and 120 rad min−1 screw speed. The results showed that the higher the FMC, the smoother the extrudate surface, the lighter the colour, and the lower the radial expansion; the water absorption index increased whereas the water solubility index was in opposite as FMC increased. The bound water was the major fraction in extruded rice flour and with FMC increasing, a shift to a long relaxation time of the peak of T21 could be found accompanied by the signal intensity enhancement. Extrusion did not alter the chemical structure of starch but turned crystal type from A to V. The rice flour possessed better digestibility after extrusion, but higher FMC mitigated the digestion by improving the branching of the starch structure and weakening the degradation of the protein.

Effects of different extrusion temperatures on physicochemical, rheological and digestion properties of rice flour produced in a pilot‐scale extruder

SummaryThis research was to study the effects of different die temperatures (125, 135, 145, 155, 165 °C) on the physicochemical, rheological, structural properties and in vitro digestion characteristics of extruded rice flour. In this work, the moisture content of feed rice flour was controlled at 18% (w/w, on a dry basis). A twin‐screw with 65 mm diameter was used. Feed rate and screw speed were set at 120 kg h−1 and 120 rad min−1 respectively to control variables. The results indicated that the water solubility index improved but the water absorption index reduced at a higher temperature. The total starch content reduced as the temperature increased, but the amylose content was insusceptible to the temperature. Average particle size significantly decreased after extrusion due to the damage of starch granules. The water dispersion system of the extruded rice flour possessed more liquid characteristics than that of raw rice flour. Steady shear analysis revealed that the flow was in a shear thinning behaviour, and apparent viscosity was improved by extrusion but negatively related to extrusion temperature. Crystal type of starch turned from A to V after extrusion. The interaction among rice flour components was mainly non‐covalent and could be enhanced by extrusion. The ratio of 1047/1022 cm−1 reflected that the ordered structure was destroyed by extrusion, which was further confirmed by the differential scanning calorimeter result. In addition, the digestibility of extruded rice flour was improved. The in vitro digestibility of protein increased from 75.77% to 86.44% and resistant starch content significantly decreased as extrusion temperature increased.

Effect of gamma-irradiation and extrusion on the physicochemical, thermal and aroma-active compounds of rice flour

Food irradiation seems to be an effective and safe method for preventing microbial and insect contamination in cereals. Interestingly, the determination of the aroma-active compounds in irradiated and extruded rice flour does not yet exist. This study aimed to investigate aroma and aroma-active compounds of non-irradiated rice flour (NIRF) and irradiated and processed rice flour (IPRF) by the SPME method combined with GC-MS-O. In the present study, twenty-three aroma-active compounds in the NIRF sample while fifteen in the IPRF sample were identified with 1.6–4.9 odor intensity scores. Hexanal [4.9], nonanal [4.4], heptanal [3.9], decanal [3.3], 3-Octen-2-one [3.1] and were detected as key odorants in all samples. Whereas, 2-penthylfuran [3.8], octanal [3.8], nonanal [4.5], and benzaldehyde [2.1] were clearly higher in the IPRF sample, considering NIRF. The amount of hexanal which can be considered as irradiation odor (IO), has been increased due to the food irradiation process.

Extruded whole grain flours and sprout millet as functional ingredients for gluten-free bread

This work aimed to use thermoplastic extrusion technology as a pretreatment for whole grain flours (corn, parboiled brown rice, and sorghum) and the incorporation of germinated millet at 5% for the production of gluten-free bread. The study characterized the flour (chemical composition and particle size distribution), evaluated the dough (pasting, empirical and fundamental rheological properties) and analyzed the bread quality characteristics (physical, structural, and textural measurements). Thermoplastic extrusion enabled the development of consistency, improved water absorption (105–153%) and viscoelastic properties of the doughs. This process caused an increase of the specific volume (66, 33 and 82%, respectively for corn, rice and sorghum made bread), and formation of better internal air cell distribution in the three different breads produced, especially in the sorghum bread. In addition, parboiled brown rice showed atypical pasting and rheological properties of the dough, which also affected the quality characteristics of the bread. The incorporation of 5% germinated millet enhanced breadcrumb softness in all samples, particularly for extruded rice flour added of germinated millet flour sample, which presented similar hardness values (7.3 N) and springiness (0.97) to whole wheat flour.

Enhancement of resistant starch content in modified rice flour using extrusion technology

AbstractBackground and objectivesThe present study was conducted with an aim to modify rice flour for enhancement of resistant starch content using extrusion technology. The effects of feed moisture, barrel temperature, and screw speed on resistant starch (RS), predicted glycemic index (pGI), glycemic load (GL), and instrumental color (L*, a*, and b* values) were investigated using response surface methodology.FindingsRS, pGI, GL, L*, a*, and b* varied between 4.91%–6.83%, 73.20–76.90, 48.0–53.04, 70.43–85.95, 6.92–10.32, and 15.09–30.81, respectively. Models obtained for these parameters were highly significant (p ≤ .0028). Significantly (p &lt; .05) higher RS content (6.20%) and lower pGI and GL values (75.10 and 50, respectively) were recorded in modified rice flour (MRF) as compared to native rice flour (NRF). Lower values of pasting properties and higher thermal properties were recorded in MRF than NRF. Scanning electron micrographs showed continuous and dense network structures in MRF, whereas ungelatinized granules were evident in NRF.ConclusionExtrusion processing caused significant changes in the digestibility of rice flour which increased the RS content and decreased the pGI in MRF. 30% moisture content, 140°C barrel temperature, and 70 rpm screw speed were found most feasible conditions to enhance RS content in MRF.NoveltyThe extrusion of rice flour without a die proved to be a unique way to produce pregelatinized rice flour with higher RS and lower pGI. MRF can be explored for development of functional foods especially for diabetic and celiac disease patients.

Effects of Psyllium Husk Content on the Physical Properties of Extruded Rice Flour

Effects of Psyllium Husk Content on the Physical Properties of Extruded Rice Flour

Influence of addition of extruded rice flour on preparation and quality of fresh gluten-free yellow alkaline noodles

Extrusion cooking was employed to physically modify structure and physicochemical properties of native rice flour (RF). In this study, blends of extruded rice flour (ERF) and RF were utilized to prepare gluten-free yellow alkaline noodles (GF-YAN). Exhibiting a cold-water swelling and a cold-peak viscosity, ERF acted as a binder paste for RF particles, thus allowing to prepare a smooth and cohesive GF dough at room temperature. Moreover, the dough could pass through a series of sheeting rollers to form a thin sheet prior to slitting into GF-YAN strands which is the traditional production process of YAN from wheat. Results showed that ERF exhibiting high peak viscosity improved tensile strength and elongation of cooked GF-YAN which implied that starch matrix developed strong binder paste. GF-YAN showed low cooking time and cooking loss. To improve texture and color, egg powder was incorporated in GF-YAN formulations. Results showed that adding egg powders improved yellow color (b* value), but decreased the noodle elongation. Confocal laser scanning micrograph revealed the swollen egg granules embedded in the starch matrix, which could disrupt the formation of continuous starch matrix and weaken the elongation property of the cooked GF-YAN. Results proved that pregelatinized ERF can be a promising alternative ingredient to prepare GF-YAN manufacturing by the traditional YAN sheeting process.

Characterization and Potential Application of Blend of Passion Fruit Peel with Rice Flour in an Extruded Product for Fiber Enhancement

By-products from the production of passion fruit juices can be a raw material for the formulation of foods with higher added value. Rice, characterized by being hypoallergenic and gluten-free, can be used with the passion fruit peel. The objective of this study was to prepare a precooked mixture by extrusion of rice flour (Rf) and passion fruit peel (Pfp) for the subsequent formulation of cookies with high fiber content and to determine the physicochemical, microbiological and sensorial characteristics of the flour and processed biscuits obtained. Experimental design of 20 treatments with (Pfp:Rf) percent ratios of 1.6/99.4, 5/95, 10/90, 15/85, and 18.4/81.6%; with moisture percentages of 14.64, 16, 18, 20 and 21.36%; and temperatures of 99.6, 120, 150, 180, and 200.4°C. The extrudates were characterized relative to the centesimal composition, dietary fiber, water absorption index (WAI), water solubility index (WSI), radial expansion index (REI), Ray-X diffraction (DRX), and microbiological stability. The results were subjected to analyses of variance and tests of comparisons of means (Tukey, p <0.05). Of three treatments, the best was chosen for use in obtaining the cookies. For ready-to-eat cookies, the formulation with 18.4% of Pfp flour showed 6.75% acceptability with the judges with an average score of 6.5, which is equivalent to I liked it slightly. For gluten-free cookies stored with microbiological stability for 120 days, the presence of microorganisms was not observed. From the technological point of view, the development of cookie formulations is a viable alternative for human consumption of precooked Pfp and Rf.

카카오 빈과 쌀 압출성형물을 첨가한 반죽의 물성 및 식빵의 품질 특성

카카오 빈과 쌀 압출성형물을 첨가한 반죽의 물성 및 식빵의 품질 특성

Shear scission through extrusion diminishes inter-molecular interactions of starch molecules during storage

The starch retrogradation behavior of native and extruded maize, wheat and rice flours were compared to better understand the efficacy of extrusion to decrease the propensity of different starches to form inter-molecular interactions. In all flour pastes, the increase of the storage modulus (G′) during a 7-day storage (representing inter-molecular interactions) was diminished with extrusion, albeit this effect was not detectable in rice due to the low gel consistency. Furthermore, thermo-rheological analyses revealed two distinct mechanisms depending on the cereal source. In maize and wheat flours, AM fragmentation through extrusion (detected through HPSEC) decreased the residual G′ at 85 °C of 7-day stored gels, which represents AM-AM physical junction zones that build gel structure. On the other hand, the extrusion of rice flour, which contains starch with lower AM ratio, resulted in a marked AP fragmentation that decreased the relative G′ drop, representing inter-molecular interactions involving AP.

Use of Response Surface Methodology to Optimize the Formulation of Rice based Gluten Free Bread and Its Characterization

The formulation for gluten free bread was optimized on the basis of specific volume, crumb firmness and overall acceptability of the bread. A rotatable central composite design (CCRD) was applied on three control variables viz. xanthan gum, extruded rice flour and corn starch varying within the range (-α to +α) of 0.5–1.5%, 15–35% and 15–35% w/w, respectively. All three responses were significantly (p&lt;0.05) affected by the combinations of independent variable. The quadratic polynomial models for the measured responses could be successfully used for their prediction during baking. The numerical optimization suggested a proportion (% w/w) of xanthan gum: rice flour: corn starch = 0.94:24.91:25.11 with high overall acceptability, comparable specific volume and crumb firmness values with respect to wheat bread. Shelf life analysis of the optimized formulation over six days revealed that, as crumb firmness increased, crust firmness and crumb moisture decreased. Keywords: Rice flour, Corn starch, Xanthan gum, Gluten free bread, Optimization, Response surface methodology

Physical and functional evaluation of extruded flours obtained from different rice genotypes

The transformation of broken grains into native flours modified by extrusion is an alternative to add value to these co-products from the paddy rice processing. This study aimed to analyze the process of extrusion cooking on the physical and functional characteristics of extruded flours obtained from different rice genotypes (IRGA-417, BRS-Primavera and CNA-8502). The experimental design was completely randomized (3x2 factorial) with four original replicates and analysis of variance to assess particle size, instrumental color parameters (L*, a* and b*), water absorption index (WAI), milk absorption index (MAI), oil absorption index (OAI), water solubility index (WSI) and milk solubility index (MSI) of rice flour. The extrusion process promoted changes in all physical and functional properties of rice flour, but only WSI and color parameters were influenced by genotype and by the industrial processing. Rice flours become darker, tending to a more reddish and yellow coloration after extrusion. Native and extruded rice flours of genotypes IRGA-417, BRS-Primavera and extruded rice flour of genotype CNA-8502 showed finer particles, while native flour of genotype CNA-8502 showed coarser particles. The extruded flours of IRGA-417 genotype obtained higher expansion and luminosity, and lower values of chroma a*, chroma b* and water solubility, while the BRS-Primavera higher values of chroma a* and b*, and lower luminosity and expansion, and CAN-8502 higher water solubility and lower expansion and value of chroma a*. The extrusion process led to flours with high water and milk absorption and solubility, low oil absorption and with potential for application in instant products, regardless of genotype.

Influence of the Addition of Extruded Flours on Rice Bread Quality

AbstractThe extrusion may improve coeliac bread quality by modifying the functional properties of flour. This study investigates the influence of the substitution of 10% of rice flour by extruded rice flours (three intensities of treatment and two particle sizes) on the characteristics of gluten‐free bread (specific volume and texture) at constant consistency. The microstructure and rheology of the doughs obtained and their behavior during fermentation have also been analyzed. The extruded flours increase dough consistency, and the effect is more noticeable with increasing intensities of treatment. The use of extruded flours requires the addition of a larger volume of water to obtain a constant consistency. The addition of extruded flour decreases dough development, producing a lower specific volume and greater bread hardness. This effect is minimized by increasing the particle size. The staling of bread from 24 to 72 h is less noticeable with a larger particle size.Practical ApplicationsThis study evidences that the use of extruded flours in rice bread making allows increasing dough hydration and therefore the bread yield while decreasing bread staling. However, the correct selection of extrusion treatment and flour particle size is essential to achieve appropriate results, being preferable the use of coarse flours with more intense extrusion treatment.

Texture Development in Gluten‐Free Breads: Effect of Different Enzymes and Extruded Flour

AbstractOne of the main problems with gluten‐free breads is their texture and their rapid staling. In this work, the influence of different enzymes (one protease, one lipase and two amylases) and of extruded rice flour on rice‐bread texture and texture development was studied. For this purpose, the development of firmness, cohesiveness, resilience, springiness and chewiness was modeled and the parameters that define the initial values and the development of these characteristics were measured. The addition of lipase and extruded flour increased bread volume and reduced the initial firmness and hardening of breads. There was an early fall in cohesiveness and resilience, with minimum values reached a few days after elaboration. There were 99.9% significant correlations between bread density and firmness, springiness and chewiness development.Practical ApplicationsThis methodology simplifies the study of gluten‐free bread textural parameters during storage and the result interpretation. Moreover, the correlation analysis has demonstrated that the number of textural parameters of gluten‐free breads to study can be reduced. Finally, the results obtained show that use of enzymes and extruded flours decreases bread staling.

Improvement of the quality of gluten-free rice pound cake using extruded rice flour

To improve the quality of gluten-free rice pound cake (GRPC), the ‘Hanarum’ extruded rice flours (HERFs) prepared with 250 rpm screw speed, 160°C barrel temperature, and 24 and 30% feed moisture of ‘Hanarum’ rice flour (HRF) were used. HERF addition reduced crude lipid and ash contents of HRF. HERF addition showed a decrease in lightness and apparent amylose content, but an increase in yellowness, water-binding capacity, and damaged starch content. Increment of solubility was higher than that of swelling power. Pasting viscosities decreased with increasing HERF content and feed moisture of HRF. The specific volume of GRPCs ranged 1.87–1.98. The hardness, springiness, and chewiness were much lower in HERF24 (24% feed moisture) and in 10% added HERF. The sensory texture and the overall eating quality were significantly different with HERF addition (p<0.05). The 10% HERF added GRPCs showed higher scores compared to control and 5% HERF added GRPCs.

제조 방법이 다른 팽화미 분말의 이화학적 특성

This study is carried out in order to develop food materials for the promotion of rice consumption. In this study, we researched the physicochemical properties of extruded rice flour (ER) and gelatinization popped rice flour (GPR) by the extrusion process and by the popped method with milled rice and brown rice. The extrusion process used a couple of screw extruders. The extrusion parameter was kept constant at a feed moisture content of 25%, barrel temperature of <TEX>$120^{\circ}C$</TEX> and screw speed of 400 rpm. GPR was prepared by batch popping machine after gelatinization of rice. In order to evaluate the physicochemical properties of ER and GPR, as well as the gelatinization rate, water soluble index (WSI), water adsorption index (WAI), DPPH radical scavenging activity and total dietary fiber content, the color value was carried out. The gelatinization rate was similar to 71.1~73.8%. Further, the results of WSI and WAI were increased at ER and GPR compared to the raw materials; ER was also higher than GPR. DPPH radical scavenging activity and total dietary fiber content showed a tendency to reduce after extrution and popping. As a result of the color value, the L value of ER decreased more than the raw materials, whereas GPR increased at a and b values.

백미와 발아현미의 혼합비율이 압출성형 멥쌀가루의 이화학적 특성에 미치는 효과

To develop the high quality gluten-free rice products with health functionality and desirable texture with moistness, the physicochemical properties of extruded rice flours prepared from the mixture of germinated brown and white rices were investigated. The domestic organic Samgwangbyeo was used to make white and germinated brown rices. White rice (WR) was dried after soaked for 6 h at <TEX>$15{\pm}3^{\circ}C$</TEX> and mixed with germinated brown rice (GBR) with different mixing ratios (100:0, 75:25, 50:50, 25:75, 0:100). The operating conditions of twin screw extruder were 250 rpm of screw speed, <TEX>$120^{\circ}C$</TEX> of barrel temperature, and 25% moisture content of rice flour. The ash, crude protein and crude lipid contents were significantly different (p<0.05) and those of extruded GBR were the highest values, but those of extruded WR were the lowest. The color difference of extruded WR based on white plate showed the lowest among them. The water binding capacity (334.16%), swelling power (8.83 g/g), solubility (33.13%), and total starch (79.50%) were the lowest in extruded GBR. The viscosities of all extruded rice flours by RVA were maintained during heating. The peak and total setback viscosities of extruded rice flours ranged 127-352 and 58.0-85.5 cP, respectively. The novel food biomaterial from germinated brown rice as well as white rice was developed by twin screw extruder. The extruded rice flours control the moistness to improve the texture and also have functional materials, dietary fiber, GABA, and ferulic acid, etc to increase quality of gluten free rice products.