Use of rice flour to produce plant-based yogurt alternatives.

Plant-based yogurt alternatives (YAs) are in demand due to the societal prevalence of milk sensitivities and allergies and some consumers abstaining from animal-derived products. Producing rice flour YAs has considerable potential because rice flour is hypoallergenic, more economical compared to plant milks, and there are no commercial rice-based YAs. A new higher protein variety of rice was developed, Frontière, which is sold as both brown and white rice. Therefore, the overall goals of this study were (1) to compare physicochemical properties of YAs from Frontière brown (Frontière brown rice flour [FBRF]) and white (Frontière white rice flour [FWRF]) high-protein rice flours to regular protein level rice flours and (2) to evaluate the sensory quality of Frontière YAs compared to commercial plant-based oat yogurt. Rice flours were fermented with Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, and Lacticaseibacillus rhamnosus (a probiotic) to produce FBRF- and FWRF-YAs. A consumer study was conducted to compare FBRF- and FWRF-YAs to a commercially available oat-based YA. Consumers rated the YAs using 9-point hedonic and just-about-right (JAR) scales. Protein, fat, and ash levels were greater, whereas starch levels and peak viscosities were lower for BRFs than for WRFs. The use of BRF resulted in longer fermentation times but higher bacteria counts for YAs. FWRF-YA was preferred in terms of overall flavor and liking, sweetness, and tartness. Purchase intent (PI) for FWRF-YA increased 2.6 times after providing a health claim. This research showed that rice flour can be used to produce YAs with probiotic counts above the minimum recommended, which provides added health benefits for consumers. PRACTICAL APPLICATION: This research provides a possible new use of Frontière high-protein rice flour to produce plant-based yogurts. This will help the rice industry by adding value, and those who are vegan, allergic to casein, or lactose-intolerant will have another option for a plant-based yogurt. Moreover, the greater levels of probiotic bacteria found in the brown rice flour YAs can potentially provide greater health benefits, making brown rice flour a better choice for making rice-based YAs.

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.

Characterization of flavor profile of Steamed beef with rice flour using gas chromatography-ion mobility spectrometry combined with intelligent sensory (Electronic nose and tongue).

The intelligent senses (Electronic nose and tongue), were combined with headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) and free amino acid were used in combination to determine the aroma and taste components during the processing of Chinese traditional dish Steamed beef with rice flour (SBD). The findings revealed that E-nose and E-tongue, could clearly distinguish and identify the aroma and taste of SBD. A total of 66 volatile substances and 19 free amino acids were identified by HS-GC-IMS and amino acid analyzer, respectively. The highest contribution to aroma in the production of SBD was alcohols, esters and aldehydes. Further analysis of relative odor activity showed that 3-Methylbutanol-D, 3-Methylbutanol-M and 3-Methylthio propanal is the marinating stage (T2) main aroma components. Ethyl 3-methylbutanoate-M and Ethyl 3-methylbutanoate-D were the main aroma components in the seasoning stage (T3). Additionally, the calculation of the taste activity value showed that Glutamic contributed significantly to the umami of SBD. Alanine was a representative taste component in the marinating stage (T2), while Proline, Aspartic, Lysine, Glutamic, Valine, Arginine, and Histidine were characteristic amino acids of the seasoning stage (T3). Consequently, this study offers valuable insights into the industrial-scale production and flavor regulation of SBD products.

Enzymatic hydrolysis method for development of low glycemic index rice flour from temperate grown rice (var. Jehlum): Numerical optimization, rheological and spectroscopic characteristics.

This study aimed at optimizing process protocols for development of low glycemic index (GI) rice flour (LGIRF) by employing enzymatic hydrolysis method using central composite rotatable design (CCRD). LGIRF was evaluated for pasting, farinographic, spectroscopic and microbiological attributes. Independent variables for optimization included concentrations of α-amylase (0.02-0.12 %), glucoamylase (0.02-0.24 %), as well as the incubation temperature (55-80°C). Resistant starch (RS), glycemic index (GI) and glycemic load (GL) were investigated as response variables. The optimum conditions for development of LGIRF with better quality were- α-amylase concentration of 0.040 %, glucoamylase concentration of 0.070 % and an incubation temperature of 60 °C. The results of mineral analysis revealed significantly (p < 0.05) lower levels of boron, potassium, zinc, phosphorus, magnesium, and manganese in LGIRF, while iron and copper were significantly higher. The viscosity profile as evident from pasting profile and farinographic characteristics of LGIRF were significantly (p < 0.05) lower than native rice flour. 1H NMR and 13C NMR spectroscopic studies showed an increase in flexible starch segments and a decrease in amorphous portion of starch LGIRF, along with chemical shift alterations in carbons 1 and 4. Free fatty acids and total plate count were significantly (p < 0.05) higher in LGIRF although was within limits.

Reduced graphene oxide decorated NiCo2(OH)6 nanoflowers for vortexed assisted dispersive µ-solid-phase extraction of organophosphorus pesticides in baby food cereal, rice and wheat flour.

Food safety is an important issue to protect humane health and improve the life quality. Hence, analysis of the possible contaminants in food samples is essential. A rapid and efficient vortexed-assisted dispersive µ-solid-phase extraction coupled with gas chromatography-mass spectrometry was proposed for simultaneous separation/preconcentration and determination of five commonly used organophosphorus pesticides. Reduced graphene oxide decorated NiCo2(OH)6 nanoflowers as a novel nanostructure was synthetized and introduced for separation of the target pesticides from the wheat flour, rice flour, and baby food cereal samples. The characterization of the nanoflowers was accomplished by SEM-EDX, XRD, and FT-IR techniques. The main factors including pH, the amount of nanoflower, the volume of sample solution, salt concentration (ionic strength), desorption conditions (i.e. desorption solvent type and volume, and desorption time) on the pesticides extraction efficiencies were inquired using matrixed match method. Applying the optimum conditions, the linearity of 0.100-500.000 µg kg-1, LODs and LOQs in the range of 0.03-0.04 µg kg-1 and 0.1 µg kg-1 for the studied food samples were obtained. The repeatability (intra-day precision (n = 5)) of ≤ 2.0 % and reproducibility (inter-day precision, days = 5, n = 3) of ≤3.1 % and were appraise at three concentration levels (10, 50 and 100 µg kg-1 of each analyte). High relative recoveries of 90.0-99.3 % ascertained high potential of the presented method for complex matrix analysis.

Removal of proteins and lipids affects structure, in vitro digestion and physicochemical properties of rice flour modified by heat-moisture treatment.

BACKGROUND: The objective of this experiment was to investigate the role of endogenous proteins and lipids in the structural and physicochemical properties of starch in heat-moisture treatment (HMT) rice flour and to reveal their effect on starch digestibility under heat. RESULTS: The findings indicate that, in the absence of endogenous proteins and lipids acting as a physical barrier, especially proteins, the interaction between rice flour and endogenous proteins and lipids diminished. This reduction led to fewer starch-protein inclusion complexes and starch-lipid complexes, altering the granule aggregation structure of rice flour. It resulted in a decrease in particle size, an increase in agglomeration between starch granules, and more surface cracking on rice granules. Under HMT conditions with a moisture content of 30%, slight gelatinization of the starch granules occurred, contributing to an increased starch hydrolysis rate. In addition, the elevated thermal energy effect of HMT enhanced interactions between starch molecular chains. These resulted in a decrease in crystallinity, short-range ordering, and the content of double-helix structure within starch granules. These structural transformations led to higher pasting temperatures, improved hot and cold paste stability, and a decrease in peak viscosity, breakdown, setback, and enthalpy of pasting of the starch granules. CONCLUSION: The combined analysis of microstructure, physicochemical properties, and in vitro digestion characteristics has enabled us to further enhance our understanding of the interaction mechanisms between endogenous proteins, lipids, and starches during HMT. © 2024 Society of Chemical Industry.

Physicochemical and rheological properties of ultrasonic-assisted pregelatinized rice flour.

This study evaluated the physical and rheological properties of whole rice flour treated for different sonication times (0-15 min). Ultrasonication reduces the particle size of rice flour and improves its solubility. Viscosity tests using RVA and steady shear showed a notable decrease in the viscosity of the rehydrated pregelatinized rice flour. Although no unusual patterns were observed in the XRD analysis, the FT-IR and microstructure morphology findings suggest that ultrasonication led to structural changes in the rice flour. Overall, the study indicates that ultrasonication is a practical and clean method for producing plant-based drinks from rice flour, which could expand its limited applications in the beverage industry.

Effects of protein-glutaminase on the properties of glutinous rice flour, paste, and gel food: Based on the interactions between the deamidated protein and starch.

In the present study, protein-glutaminase (PG) from Chryseobacterium proteolyticum was applied to improve the processing properties of glutinous rice flour (GRF). After PG modification, the degree of deamidation of glutinous rice protein (GRP) reached 13.6% at 2.0 h, with smaller particle size and decreased zeta potential. The interaction of GRP with starch in PG-modified GRF (PM-GRF) was changed, exhibiting in protein aggregates decreasing and exposure of starch on the surface of GRF. Compared with unmodified GRF (UM-GRF), the solubility and turbidity of PM-GRF were both increased. The rheological properties reflected that the viscosity of PM-GRF paste was increased, and the freeze-thaw stability was also enhanced. Moreover, the textural characteristics showed that the hardness of PM-GRF balls remarkably reduced and the springiness increased. These results indicate that deamidation by PG could be an efficient method for improving characteristics of GRP and GRF.

Effects of Stir-Frying and Heat-Moisture Treatment on the Physicochemical Quality of Glutinous Rice Flour for Making Taopian, a Traditional Chinese Pastry.

Taopian is a traditional Chinese pastry made from cooked glutinous rice flour. The effects of heat-moisture treatment (110 °C, 4 h; moisture contents 12-36%, w/w) on the preparation of cooked glutinous rice flour and taopian made from it were compared with the traditional method of stir-frying (180 °C, 30 s). The color of heat-moisture-treated (HMT) flours was darker. HMT flours exhibited a larger mean particle size (89.5-124 µm) and a greater relative crystallinity of starch (23.08-42.92%) and mass fractal dimension (1.77-2.28). The flours exhibited water activity in the range of 0.589-0.631. Although the oil-binding capacity of HMT flours was largely comparable to that of stir-fried flours, HMT flours exhibited a lower water absorption index. Accordingly, the taopian produced with HMT flours exhibited a lower brightness, accompanied by a stronger reddening and yellowing. In addition, more firmly bound water was observed in the taopian produced with HMT flour. The taopian made with HMT flour with a moisture content of 24% exhibited moderate hardness, adhesiveness and cohesiveness and received the highest score for overall acceptability (6.80). These results may be helpful to improve the quality of taopian by applying heat-moisture treatment in the preparation of cooked glutinous rice flour.

Physicochemical characterization of a composite flour: Blending purple sweet potato and rice flours.

In this study, the physicochemical characterization of different ratios of purple sweet potato flour (PSPF) and rice flour was investigated to improve the nutritional value and enrich the variety of rice-based staple food. The results showed that adding PSPF increased total dietary fiber and anthocyanin content whereas decreased amylose content of the composite flours. Additionally, the composite flours exhibited lower thermodynamic parameters and displayed darker, redder, and bluer colors. There were no noticeable changes in the functional group structure of the composite flours. The addition of PSPF decreased the crystallinity and water-holding capacity of the composite flours, whereas increased the average particle size and iodine blue value. PSPF increased the pasting temperature of the flours whereas decreased the breakdown and setback values. Overall, the addition of PSPF significantly affects the nutrition, color and physicochemical properties of the composite flours.

Evaluation of oxidative stability of rice oil from brown rice flour under thermal oxidation and light irradiation.

Effects of autoxidation and light irradiation on the oxidative stability were evaluated in rice oil from two brown rice flours including 'Baromi2' and 'Samkwang'. 'Baromi2' is a newly developed variety for rice flour production while 'Samkwang' is a typical rice variety as a control. Degree of oxidation and volatile profiles were evaluated in rice oil stored at 60 °C or under fluorescent light at 25 °C. The oil yields of 'Baromi2' and 'Samkang' were 2.63 and 1.78%, respectively whereas rice oil from 'Baromi2' had lower degree of unsaturation than 'Samkang'. Rice oil from 'Samkwang' possessed higher volatile compounds and more oxidized products during autoxidation whereas rice oil from 'Baromi2' had more oxidation products under light irradiation. Hexanal and 2-heptenal were major headspace volatile from heated rice oil while 2-heptenal and 1-octene-3-ol were main volatiles from light irradiated rice oil, which implies the involvement of singlet oxygen in rice oil during photooxidation.

Effect of superheated steam treatment on enzyme inactivation, morphostructural, physicochemical and digestion properties of sand rice (Agriophyllum squarrosum) flour.

The lipase (LA) and peroxidase (POD) activities, as well as morphological structure, physicochemical and digestion properties of sand rice flour (SRF) treated with superheated steam (SS), were investigated. SS treatment at 165 °C completely deactivated LA and resulted in a 98% deactivation of POD activities in SRF. This treatment also intensified gelatinization, induced noticeable color alterations, and decreased pasting viscosities. Furthermore, there was a moderate reduction in crystal structure, lamellar structure, and short-range ordered structure, with a pronounced reduction at temperatures exceeding 170 °C. These alterations significantly impacted SRF digestibility, leading to increased levels of rapidly digestible starch (RDS) and resistant starch (RS), with the highest RS content achieved at 165 °C. The effectiveness of SS treatment depends on temperature, with 165 °C being able to stabilize SRF with moderate changes in color and structure. These findings will provide a scientific foundation for SS applicated in SRF stabilization and modification.

Effect of endogenous protein and lipid removal on the physicochemical and digestion properties of sand rice (Agriophyllum squarrosum) flour.

The study investigated the effect of removing protein and/or lipid on the physicochemical characteristics and digestibility of sand rice flour (SRF). Morphological images showed that protein removal had a greater impact on exposing starch granules, while lipids acted as an adhesive. The treatment altered starch content in SRF samples, leading to increased starch crystallinity, denser semi-crystalline region, lower onset gelatinization temperature (To), higher peak viscosity and gelatinization enthalpy (ΔH), where Protein removal showed a more pronounced effect on altering physicochemical properties compared to lipid removal. The research revealed a positive correlation between rapidly digestible starch (RDS), maximum degree of starch hydrolysis (C∞), digestion rate constant (k) values and 1047/1022 cm-1 ratio, showing a strong connection between short-range structure and starch digestibility. The presence of endogenous proteins and lipids in SRF hinder digestion by restricting starch swelling and gelatinization, and physically obstructing enzyme-starch interaction. Lipids had a greater impact on starch digestibility than proteins, possibly due to their higher efficacy in reducing digestibility, higher lipid content with greater potential to form starch-lipid complexes. This study provides valuable insights into the interaction between starch and proteins/lipids in the sand rice seed matrix, enhancing its applicability in functional and nutritional food products.

Quinoa (Chenopodium Quinoa Willd.) as Functional Ingredient for the Formulation of Gluten-Free Shortbreads.

The incidence of celiac disease and gluten intolerance has been significantly rising globally. Gluten-free product consumption registered a sudden rise also among tolerant people, due to psychosocial factors. Biscuits are popular, low-cost bakery foods, consumed by nearly everyone worldwide. The removal of gluten from the baked product causes some undesirable traits and different textures and tastes. The main goal consists in creating a food product with the same taste and texture as a product with gluten. Moreover, gluten-free bakery products are usually low-grade sources of protein and poor in dietary fiber. Quinoa is a source of total dietary fiber and valuable protein. In this study, quinoa flour was used as the main constituent in the formulation of gluten-free shortbreads to improve their nutritional properties. Six different recipes with different percentages of quinoa flour have been realized. The formulations were compared with each other and with a wheat flour control shortbread, using textural analysis. The experimental biscuits with textural features more similar to control shortbread were subjected to a triangle-discriminating and preference test and those selected by panelists was characterized from a chemical-physical and sensorial point of view. The experimental shortbreads constituted a good compromise to exploit the good nutritional composition of quinoa while maintaining an acceptable sensory profile.

Structure, properties, and resistant starch content of modified rice flour prepared using dual hydrothermal treatment.

In this study, modified rice flour with high resistant starch (RS) content was prepared by dual hydrothermal treatment, which combined the heat-moisture treatment with the pressure-heat treatment method. The effects of dual hydrothermal treatment on the structure and properties of modified rice flour and their relationship with RS content were further discussed. The results showed that the RS content of modified rice flour was higher than that of rice flour (RF), and dual hydrothermal treatment was more effective than single hydrothermal treatment. Adhesion and aggregation occurred between the particles of modified rice flour. Both crystallinity and short-range ordering were increased in modified rice flour compared to RF. Moreover, the modified rice flour of dual hydrothermal treatment had higher crystallinity and a more ordered short-range structure of starch, which improved RS content to a certain extent. Compared to single hydrothermal treatment, the modified rice flour of dual hydrothermal treatment had a lower viscoelasticity and a better thermal stability. Both RF and modified rice flour gels were composed mainly of free water, with minimal amounts of bound and immobile water. The study may provide a reference for the production and application of modified rice flour.

New Insights into the Comprehensive System of Thermodynamic Sensors and Electronic Nose and Its Practical Applications in Dough Fermentation Monitoring.

This study focuses on an applicability of the device designed for monitoring dough fermentation. The device combines a complex system of thermodynamic sensors (TDSs) with an electronic nose (E-nose). The device's behavior was tested in experiments with dough samples. The configuration of the sensors in the thermodynamic system was explored and their response to various positions of the heat source was investigated. When the distance of the heat source and its intensity from two thermodynamic sensors changes, the output signal of the thermodynamic system changes as well. Thus, as the distance of the heat source decreases or the intensity increases, there is a higher change in the output signal of the system. The linear trend of this change reaches an R2 value of 0.936. Characteristics of the doughs prepared from traditional and non-traditional flours were successfully detected using the electronic nose. To validate findings, the results of the measurements were compared with signals from the rheofermentometer Rheo F4, and the correlation between the output signals was closely monitored. The data after statistical evaluation show that the measurements using thermodynamic sensors and electronic nose directly correlate the most with the measured values of the fermenting dough volume. Pearson's correlation coefficient for TDSs and rheofermentometer reaches up to 0.932. The E-nose signals also correlate well with dough volume development, up to 0.973. The data and their analysis provided by this study declare that the used system configuration and methods are fully usable for this type of food analysis and also could be usable in other types of food based on the controlled fermentation. The system configuration, based on the result, will be also used in future studies.

Development of Gluten-Free Bread Production Technology with Enhanced Nutritional Value in the Context of Kazakhstan.

This research aims to enhance the nutritional value of gluten-free bread by incorporating a diverse range of components, including additives with beneficial effects on human health, e.g., dietary fibers. The research was focused on improving the texture, taste, and nutritional content of gluten-free products by creating new recipes and including novel biological additives. The goal was to develop gluten-free bread with less than 3 ppm gluten content that can be eaten by people suffering from gluten sensitivity. The physical and chemical properties of gluten-free rice, corn, green buckwheat, chickpea, amaranth, and plantain flours were examined to understand their unique characteristics and the possibility of their mixing combination to achieve the desired results. Initially, nine recipes were prepared, and in survey research, four baking recipes were selected and tested. The composition of amino acids in the prepared gluten-free bread was determined. The variant made of corn, green buckwheat flour with plantain was found to be top-rated. Changes in the nutritional content of the new product were analyzed, and general regulations and nutritional values were identified. Experimental baking processes were carried out, leading to the successful formulation of gluten-free bread containing corn, green buckwheat, and plantain flour in a ratio of 40:40:20, meeting gluten-free requirements and demonstrating improved nutritional properties, as well as consumption properties, confirmed by surveys conducted on a group of consumers.

Multi-residue monitoring and dietary risk assessment of 17 pesticides and 3 related metabolites in rice and rice flour from markets in China.

Pesticide residues in rice have attracted widespread public attention in recent years. This research aimed to monitor the residues of 17 pesticides and their 3 metabolites in 120 samples of rice and rice flour collected from markets in China using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) pretreatment method combined with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The monitoring results showed that isoprothiolane, tricyclazole, fenoxanil, and tebuconazole were detected in the rice samples, with detection frequencies of 33.3%, 17.5%, 8.3%, and 2.5%, and concentrations ranging from 0.02 to 0.1 mg/kg (median = 0.04), 0.01 to 0.17 mg/kg (median = 0.14), 0.04 to 0.06 mg/kg (median = 0.05), and 0.01 to 0.02 mg/kg (median = 0.01), respectively. The residues of these four pesticides were all below their corresponding maximum residue levels (MRLs) set by China. Additionally, isoprothiolane, tricyclazole, fenoxanil, and tebuconazole were detected in rice flour samples, with detection frequencies of 74.2%, 55.0%, 5.0%, and 2.5%, and concentrations ranging from 0.01 to 0.1 mg/kg (median = 0.04), 0.01 to 0.04 mg/kg (median = 0.02), 0.01 to 0.06 mg/kg (median = 0.03), and 0.02 to 0.04 mg/kg (median = 0.03), respectively. Furthermore, the chronic dietary intake risk (HQc), the acute dietary intake risk (HQa), and cumulative dietary risk (HI) for all the detected pesticides were evaluated and found well below 100%, indicating that the dietary intake risks would not pose potential health risks.

Effects of NaCl on the Physical Properties of Cornstarch-Methyl Cellulose Blend and on Its Gel Prepared with Rice Flour in a Model System.

This study investigated the impact of NaCl on the physical properties of cornstarch-methyl cellulose (CS-MC) mixtures and their gels prepared with rice flour in a model system. Opposite trends were observed, showing that NaCl led to decreased viscosity of the CS-MC mixtures (liquid-based), whereas a more stable and robust structure was observed for the rice-flour-added gels (solid-based) with the addition of NaCl. The interference of NaCl with the CS-MS blend's ability to form a stable gel network resulted in a thinner consistency, as the molecules of the CS-MS blend may not bind together as effectively. On the contrary, NaCl showed the potential to enhance the protein network within CS-MC gels prepared with rice flour, thereby contributing to an augmentation in the stability or firmness of the cooked gels. Careful utilization of NaCl to optimize the physical properties of the CS-MC blends, as well as the gels based on rice flour, should be performed.

Transmembrane behaviors and quantitative structure-activity relationship of dietary flavonoids in the presence of intestinal digestive products from different carbohydrate sources based on in vitro and in silico analysis.

Bioavailability plays a key role for flavonoids to exert their bioactivities. This study investigated the transmembrane transport behavior and structure-activity of dietary flavonoids. Results showed that the apparent permeability coefficients of some flavonoids could be significantly increased when digestion products from rice flour (RD) or wheat flour (WD) are present (p < 0.05), especially in the WD, potentially due to higher reducing sugar (p < 0.05). 3D-QSAR revealed that the hydrogen bond acceptor groups at positions 5 and 6 of ring A, small-volume groups at position 3', hydrophobic groups at position 4', and large-volume groups at position 5' of ring B increased the transmembrane transport of flavonoids in the WD. A hydrogen bond donor group at position 4' of ring B enhanced the transmembrane transport of flavonoid compounds in the RD. These findings contribute to our comprehensive understanding of flavonoid absorption within the context of intestinal carbohydrate digestion.