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The aim of the current study was to evaluate the possibility of the bacterial growth and substrate metabolism during the fermentation of red grape juice and the mixture of red grape juice and rice flour solution using Lactobacillus plantarum and Lactobacillus casei. In recent years, cereal‐based beverages have been used as functional compounds such as antioxidants, dietary fiber, minerals, probiotics, and vitamins in diets. In this research, fermentation of red grape juice (media 1) and 1:1 mixture of red grape juice and rice flour solution (media 2) by two strains of gram positive and homofermentative lactic acid bacteria: L. plantarum and L. casei (individually and mixed) was examined. Fermentation was carried out at 37°C for 48 hr. Microbial population, pH, acidity, sugar, and organic acid metabolism were measured during the fermentation period. Data showed that in media 2 fermented with mixed culture of both L. plantarum and L. casei, acidity and microbial population increased sharply at the initial stages of fermentation, and the most percentage of lactic acid production occurred. Red grape juice fermented with mixture of L. plantarum and L. casei showed the most sugar consumption (p

The physicochemical properties, swelling power, solubility, and digestibility of flour from four rice varieties (black, brown, white, and waxy rice flour) were analyzed. The results showed that the black and brown rice had high‐amylose percentage (21.8% and 20.5%), a relatively low percentage of starch content (68.1% and 79.1%), and lower swelling power (6.6% and 7.6%) and solubility (13.5% and 15.7%), respectively. Waxy rice flour attributed to lower gelatinization temperatures and higher enthalpy values. Meanwhile, the brown, black, and white rice showed higher gelatinization temperature and lower enthalpy value. The black and brown rice flour exhibited lower pasting and viscosity values as compared to waxy rice flour. The results showed that all rice flour had an A‐type X‐ray diffraction pattern, and after cooking all rice flour showed V‐type polymorphs except waxy rice flour. Brown and black rice flour after cooking have lower digestion rate than white rice and waxy rice flour, probably due to its lower expansion and solubility rates, and higher gelatinization temperature., Rosa Roxburghii seed oil was of high quality in terms of its high amount of unsaturated fatty acids. Heat treatment of R. roxburghii seed oil showed an increase in the relative percentage of linoleic acid and linolenic acid isomers with increasing temperature and time. The formation of linoleic acid and linolenic acid isomers followed a zero order reaction.

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A process for enhancing textural and cooking properties of fresh rice flour-soy protein isolate noodles (RNS) to match those of yellow alkaline noodles (YAN) was developed by incorporating microbial transglutaminase (RNS-MTG), glucono-δ-lactone (RNS-GDL), and both MTG and GDL into the RNS noodles (RNS-COM). The formation of γ-glutamyl-lysine bonds in RNS-COM and RNS-MTG was shown by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Scanning electron microscope showed that compared to others, the structure of RNS-COM was denser, smoother with extensive apparent interconnectivity of aggregates. The optimum cooking time was in the order: YAN > RNS-COM > RNS-MTG > RNS-GDL > RN (rice flour noodles); tensile strength was in the order: YAN > RNS-COM > RNS-MTG > RNS-GDL > RN; and elasticity were in the order: YAN > RNS-COM > RNS-MTG, RNS-GDL > RN. Overall, RNS-COM showed similar textural and structural breakdown parameters as compared to those of YAN. Changes in microstructures and improvement of RNS-COM in certain properties were likely due to enhanced crosslinking of proteins attributed to MTG- and GDL-induced cold gelation of proteins at reduced pH value. It is possible to use the combination of MTG and GDL to improve textural and mechanical properties of RNS comparable to those of YAN. PRACTICAL APPLICATION: Combined MTG and GDL yield rice flour noodles with improved textural properties. The restructured rice flour noodles have the potential to replace yellow alkaline noodles.

Waxy, low‐ and high‐amylose rice were cooked at different temperatures (50, 70, 90 °C) for different times (15, 30, 45 min). The microscopic, rheological and gel textural properties of resultant flours were investigated. There was a coarser and discontinuous honeycomb‐like structure with formation of pores in rice flour with greater cooking degree. TGʹₘₐₓ was positively correlated with cooking temperature and time. As cooking temperature increased, the Gʹ values of pastes first increased and then decreased, whereas the opposite trend was observed for tan δ. Meanwhile, increased cooking temperature was responsible for increases in n values and caused drops in K and hysteresis area. As cooking time increased, the hardness and gumminess of gels from rice cooked were increased at lower temperature, but were decreased at higher temperature. Overall, cooking temperature was more important in determining the processing properties of rice flours than cooking time.

This study developed functional muffin by incorporating bioactive‐rich food materials into rice muffin formulation. Rice flour was progressively replaced with shiitake mushroom powder (MP) and carrot pomace powder (CP) and effects on pasting, physical and textural properties, as well as the antioxidant activity and consumer acceptability, were evaluated. The pasting properties of rice flour were significantly influenced (P

Gluten-free flours based products present technological difficulties in their preparation, the texture is very different in comparison to products that contain gluten and their nutritional quality is often deficient due to the use of starches and refined flours, which provide high energy density and low nutritional value. The aim of this research was to assess the effects of addition both whole and malted quinoa flours on the physical, nutritional and sensory characteristics of gluten-free muffins. Different formulations were assessed: with 100% rice flour and with a 30% replacement for whole or malted quinoa flour. Proximate composition analysis, baking associated weight loss, size, specific volume, crumb structure, texture profile and consumer test sensory analysis were tested on the samples. Quinoa flours produced an increase of between 12% and 18% on protein, 8% to 18% on minerals and 22% to 25% on amino acids, in comparison to samples that contained only rice flour (used as reference). Technological and sensory improvements on the quality of assessed muffins were also associated to quinoa flours addition. 24 hr-malted quinoa flour added muffins had moisture, height, volume and firmness that were close to the reference ones. On all samples, small cells (0.002 to 0.005 cm2 ) were predominant on crumb structure and sensory evaluation resulted on similar outcomes for color and texture. However, the formula with 24 hours-malted quinoa flour had the best scored on taste and smell. PRACTICAL APPLICATIONS: Adding whole or malted quinoa flours to formulations of gluten-free products improves their nutritional and technological characteristics. These new products not only widen food variety for people with celiac disease but also increase the added value of quinoa grains, which motivates its production and industrialization.

Response surface methodology based on Box–Behnken was used to assess the effects of three kinds of texture‐improving ingredients, namely, mixed starch (MS) (6%–8%) of sweet potato starch and glutinous rice flour, k‐carrageenan (CG) (0.4%–0.6%), and konjac flour (KF) (0.8%–1.2%), on the firmness, elasticity, and water holding capacity (WHC) of emulsified sausage (ES) made from pork and salted egg white (SEW). The three kinds of texture‐improving ingredients individually presented different effects on firmness, elasticity, and WHC. Their synergistic effects were significant. The three response models obtained by ANOVA were suitable to predict firmness, elasticity, and WHC. These models can also be used to design formulations for different types of sausage with different firmness and elasticity. The combination of MS (7.36%), CG (0.60%), and KF (1.20%) can produce SEW‐containing ES with remarkable firmness (224.04 g), elasticity (8.62), and WHC (8.41).

Summary This study aimed to investigate effect of butter content (0–30 g/100 g flour) and baking conditions hot air baking (HA), microwave baking (MW) and hot air-microwave baking (HA-MW) on quality of the rice flour dough and bread. The increased butter (up to 15 g butter/100 g flour) enhanced elastic modulus (G′) and viscous modulus (G″) of dough and specific volume of bread. Additionally, the increased butter improved crust colour and reduced hardness of the bread. The HA-MW and MW conditions were useful for the gluten-free bread by reducing baking time and predicted glycemic index (GI), regardless of butter content. However, enthalpy of retrogradation and crystallinity in the HA-MW and MW bread stored at 4 °C for 7 days were increased and higher than those of the HA bread, indicating a faster staling. The predicted GI of both MW and HA-MW bread remained at a medium level during storage.

Fissuring caused by rapid moisture adsorption generates broken kernels upon milling; brokens are often ground to flour. The recent increase in demand for rice flour has promoted interest in brokens. This study investigated the physical and functional characteristics of brokens resulting from milling lots with various levels of moisture adsorption-induced fissuring. Two long-grain (LG) cultivars and one medium-grain (MG) cultivar were conditioned to five initial moisture contents (IMCs), rewetted, and then reconditioned to 12% moisture content. Brown rice fissure enumeration and milling analyses as well as size distribution and functionality analyses of brokens were conducted. As IMC decreased, the percentage of fissured kernels increased and, consequently, the amount of brokens generated increased. Although the number of fissures/kernel also increased with decreasing IMC, the mass distribution of the resultant brokens was not affected by IMC. Across all IMC levels, the mass percentage of the medium-sized ...

The chemical modification of rice flour by phosphorylation is an alternative to improve the technological quality of bakery products. The aim of this study was to investigate the effect of phosphorylation process of rice flour on technological properties (specific volume, crumb and crust colour) of gluten-free breads and the hardening of these breads during two storage temperatures (21 °C and −24 °C). Breads were made with native rice flour, with phosphorylated rice flour and with wheat flour, used as control. The phosphorylation causes significant reduction in the synaeresis of pastes and in retrogradation tendency of rice flours, varying from 258.7 cP (native rice flour) to 122 cP (phosphorylated rice flour). The breads prepared with phosphorylated rice flour showed reduction in the hardness in both storage temperatures studied and effect on rice bread volume, crumb appearance and colour, demonstrating the possibility of use of the phosphorylated rice flour in gluten-free breads.

Using rice flour and Agaricus bisporus powder as raw materials, a puffed snack was developed by twin‐screw extrusion technology. The Box–Behnken design method was used to optimize the process variables with three factors in three levels. The experimental variables were included temperature (135°C–155°C), moisture (13%–17%) and the addition amount of A. bisporus powder (3%–7%). The extrudate properties were evaluated by determining the expansion ratio. The optimization results indicated that the extrusion temperature was adjusted to 149°C, the moisture content of raw materials was 14.4%, and the addition of A. bisporus powder was 4.2%. Under these conditions, the expansion rate of the product was up to 3.41. The obtained extruded snacks had good taste, high expansion ratio and loose porosity. Compared with snacks without A. bisporus powder, the puffed snacks had better characteristics (high consumer tasting score, relatively low hardness). PRACTICAL APPLICATIONS: After making the puffed snacks, fruits and vegetables were easy to store and transport and enrich the products of A. bisporus. The puffing rate, consumer evaluation and hardness of A. bisporus snacks were studied, which provided a theoretical basis for optimizing the processing characteristics of A. bisporus. Agaricus bisporus and rice flour provided great space for the development of puffed food.

The aim of this study is to analyze the effect of replacing rice (0–15% and 30%) and chickpea flours (0–15%) by pregelatinized maize starch on physical, textural, and sensorial properties of gluten‐free pregelatinized maize starch cake. The L* and a* color values of the cakes are significantly (p < 0.01) affected by the replacement of rice and chickpea flours with pregelatinized maize starch. Cakes containing chickpea flour present darker crumbs as well as lower a* values compared with cakes containing rice flour and control cake containing only pregelatinized maize starch. The hardness significantly (p < 0.05) increases only in presence of chickpea flour. The springiness, cohesiveness, and chewiness values show similar trend for all samples and these parameters increase with the addition of rice and chickpea flours. In general, the cake‐specific volume values increase with the addition of rice and chickpea flours. The sensorial parameters of the cakes significantly change with the addition of rice and chickpea flours. According to results of sensorial evaluation, the formulations containing 15% rice and 15% chickpea flours are identified as the best cake formulations. The results show that the quality of maize starch cake could be improved by adding rice and chickpea flours.

The effects of rice flour on the physicochemical properties of the raw material system and the quality of extruded potato–rice noodles were studied. The results demonstrated that the amylose content, pasting viscosities, storage modulus (G′), and loss modulus (G″) gradually increased with the included levels of rice flour, whereas the swelling power, solubility, and pasting temperature decreased with increasing rice flour content. The extruded potato–rice noodles exhibited desirable cooking qualities and textural properties with rice flour contents of up to 40%. Additionally, sensory evaluations revealed that the scores for chewiness, firmness, slipperiness, elasticity, and overall acceptability increased gradually with increasing rice flour content in the blends. Additionally, the results indicated the possibility of replacing potato flour with rice flour at a ratio of 6:4 to produce extruded potato–rice noodles of acceptable quality.

The objective was to examine the potential use of resistant starch (RS) as a fibre-enriching ingredient in gluten-free pasta. Pasta was enriched with commercial RS type II (Hi-Maize™ 260) at 100-200 g kg-1 substitution of rice flour. The effects on the rheological properties of dough and pasta quality as a result of RS addition and the loss in RS due to the process were evaluated.; Results: Dough water absorption was not influenced by the addition of RS. The cooking loss (CL) of RS-enriched samples was 30% lower than reference without fibre. The addition of RS significantly increased firmness of cooked pasta, and above 100 g kg-1 RS level of substitution samples showed a lower stickiness value. Dynamic rheological tests on pasta dough showed a higher storage modulus for fibre samples, indicating a higher number of elastically physical interactions. Loss in RS in uncooked pasta was about 31% compared with the initial amount added to the product.; Conclusions: The addition of RS improved the quality of gluten-free pasta owing to its ability to increase the firmness and decrease the CL and stickiness of cooked pasta. The product enriched with 200 g kg-1 RS can be considered a source of DF. © 2016 Society of Chemical Industry.; © 2016 Society of Chemical Industry.

Summary The effect of an addition of shrimp protein hydrolysate and shrimp powder on the physicochemical properties of extruded snack was studied. Rice flour and cornflour were used as base materials, and extrusion was done using corotating twin-screw extruder. A mixture response surface methodology was used to study the effect of ingredient mixture on the physical, functional and sensory properties of extrudates. Linear and quadratic mixture response regression model was fitted to the response variables, and it was evaluated using R2 values. Based on the desirability function score, the optimum combination of ingredient was 47.75% rice flour, 38.64% cornflour, 5.95% hydrolysate and 7.67% shrimp protein powder. It was observed that an addition of shrimp hydrolysate more than 5% (7.5%) improved the crispiness. Sensory evaluation revealed that shrimp hydrolysate and shrimp powder can be used at 5–7.5% level for developing protein-rich extruded products without affecting sensory characteristics.

The influences of chestnut flour at different levels (0, 20, 40, 60, 80 and 100%) on the rheological properties of rice dough formulations and the quality parameters of gluten-free cookies were evaluated. Elevated flour replacement levels led to increases in extensional viscosity values reflecting higher force requirement to deform dough samples. Similarly, replacement of rice flour with chestnut flour led to higher complex moduli values. Cookie samples prepared by replacement of 40% rice flour with chestnut flour had the softest texture and elevated levels of chestnut flour increased hardness values. In general, as the higher amounts of rice flour were replaced with chestnut flour, the spread ratio of cookies was decreased. The replacement of rice flour with chestnut flour decreased L* values and increased a* and b* values of the cookie samples. Observing all the evaluated sensory attributes, using 40% flour replacement level in gluten-free cookie formulation significantly enhanced sensory properties of the cookie samples. Practical Applications Chestnut flour provides both health and nutritional benefits. Besides, the ingredients of chestnut flour may positively influence functional properties of dough. The quality of gluten-free cookies may be improved by the use of chestnut flour in gluten-free cookie formulations. This study aims to provide experimental evidence for the potential use of chestnut flour as a gluten-free flour alternative in cookie formulations. Therefore, in the present study, the effects of replacement of rice flour with chestnut flour at different levels on the rheological properties of cookie dough formulations as well as on the quality parameters of cookies were evaluated. The results of the present study showed that the problems associated with using only chestnut or rice flour can be overcome by the potential synergistic effect of using of chestnut and rice flour together in the formulation and this synergic interaction was found to be effective on improving of gluten-free cookies with desired quality.

To develop gluten free bread, rice flour dough with the addition of whey protein concentrate (WPC, 0–6 g/100 g flour) was baked under three conditions – hot air baking (HA), microwave baking (MW) and microwave-assisted hot air baking (HA-MW). An increase in the WPC content increased the volume and the moisture content of the bread (P ≤ 0.05). The MW and HA-MW methods increased the hardness of bread crumbs and the L* value of the bread crust (P ≤ 0.05). The estimated glycemic index (GI) of the HA bread was 80.34 ± 0.88. With the addition of 6 g WPC/100 g flour, the GI was reduced to 70.46 ± 1.70. By changing from HA to MW, the GI was further reduced to 61.67 ± 0.69. Without the addition of WPC, enthalpy of retrogradation (ΔH) of the freshly baked bread using MW was higher than from HA and HA-MW. The enthalpy tended to increase with increased storage time. Practical Applications Microwave could increase the heating rate during baking and affect the protein-starch matrix in gluten free bread made from rice flour. Consequently, bread made using the microwave baking method has low starch digestibility and a high enthalpy of retrogradation with increased volume. Therefore, MW with the addition of whey protein concentrate is recommended to develop crustless, gluten-free bread with a reduced glycemic index, which is good for people who suffer from obesity, diabetes and celiac disease.

Summary Nonconventional raw materials have been applied in gluten-free pasta, to meet the demand of people with coeliac disease. The objective of this study was to evaluate the cooking properties and texture of pasta formulated with rice flour, defatted flaxseed flour and pregelatinised mixed flour of rice and flaxseed (80:20). For this experiment, simplex design was used. Cooking properties and texture were found within the quality limits established for this type of product. The pasta with the most desirable properties (short optimum cooking time (OCT), less solid loss (SL) and intermediate mass increase (MI)) was that one formulated with 43 g 100 g−1 of pregelatinised flour, 47 g 100 g−1 of rice flour and 10 g 100 g−1 of defatted flaxseed flour. This formulation can be characterised as a food rich in dietary fibre and of high nutritional value.

New possibilities for using freeze-dried rice sourdoughs in the processing of gluten-free bread (GFB) are demonstrated in this study. Fresh and freeze-dried (at temperatures of 20 and 40C) rice sourdoughs were added in the amounts of 10, 20, 30 and 40% of the total flour content. Significant and beneficial changes in the texture (elasticity and cohesiveness) of bread under the influence of different quantities of fresh and freeze-dried sourdough addition were observed. In most cases, there were no significant differences between the firmness and cohesiveness of bread made with fresh or freeze-dried sourdough. A lower degree of crumb staling was obtained for bread produced with a 10% addition of fresh sourdough and sourdough freeze-dried at 40C. The best overall sensory assessment was achieved by bread with 10 and 20% rice sourdough. At these levels of sourdough addition, there were no significant changes in the assessment of bread made with either fresh or lyophilized sourdough. Sensory evaluation of texture was positively correlated with other physical properties: pore area, firmness, elasticity and cohesiveness of crumb (r = 0.869; 0.836; 0.596; 0.848, respectively) and negatively correlated with bread pH values (r= −0.801). Practical Application The results have important significance, as the use of freeze-dried rice sourdough may improve the process of the production of natural GFB. Freeze-dried rice sourdoughs used directly in processing eliminate the requirement for a long period of fermentation of the sourdough. Freeze-dried rice sourdough, in an amount of 10 or 20%, may be a good substitute for fresh sourdough. An increase in heating plate temperature from 20 to 40C caused a decrease in drying time of about 25%; therefore, to produce this sourdough, a freeze-drying temperature of 40C is suggested. The bread is distinguished by a favorable qualitative assessment. Also, the reduced pH value has a beneficial influence on extending bread durability and freeze-dried rice sourdough can be used as a natural preservative.

The digestibility and hydration properties of wet-ground submicron-scale rice flour were compared with those of dry-ground coarser microscale flours. The submicron flour (mean size 0.6 µm) was produced in a wet-media mill with 0.3 mm zirconia beads by continuous 24 h pulverization. The solubility, water absorption index, and swelling power increased as the mean particle size decreased, reaching maximum values in the submicron flour. Starch damage was high in the submicron flour, with the absence of intact starch granules. The digestibility also increased as the particle size decreased, and it was highest in the submicron flour. These results show that wet-ground submicron rice flour has different functional properties from dry-ground coarser flour. The digestibility was more strongly influenced by starch damage and the water absorption index than by the mean particle size.

Rice kernels were steeped (10°C, 5 h) in an aqueous solution containing gum arabic (0.36%) and xanthan (0.24%) and then drained, wet-milled, and steamed to prepare rice cakes. The cakes were then frozen (–40°C for 50 min). The effect of the gum addition on the textural properties of the cakes during storage for 46 h at 25°C after being thawed was examined. Using the combination of gum arabic and xanthan mitigated the quality deterioration of rice cakes such as aggregation of rice flour, which had been induced by xanthan alone. Also, the increase in hardness during storage was substantially reduced by soaking rice kernels in the gum arabic/xanthan solution. Overall results revealed that the steeping in the gum solution improved the storage stability of rice cakes.

A simple method employing a commercially available canister was developed for the determination of mode of water absorption of rice flour samples. The samples prepared by four different grinding methods were used to analyze water absorption. The total amount of water in a flour sample was described by using an exponential model. Capacity and rate of water absorption of the samples were determined, and the relationship to baking quality of partially substituted rice bread was investigated. The water absorption was highly dependent on the method of grinding. Flours produced by wet jet-milling of the grains, which absorbed a small amount of water at high speed, were most suitable for rice bread. The method was applicable to other food powders, provided that flour particles do not stick together or swell immediately upon contact with water.

The effect of blending wheat flour (WF) on broken rice flour (BRF) at various levels (0, 20 40, 60, 80 and 100 g/100 g) were assessed for their suitability in noodles making. Physicochemical and functional properties of prepared noodles from these blends were studied. The proximate composition of uncooked noodle samples varied significantly (p

Summary The effect of three different rice varieties with different starch shapes (Seolgaeng (SG), round starch structure; Samkwang (SK), polygonal starch structure and Boramchan (BRC), polygonal starch structure) on rice flour characteristics and gluten-free bread baking quality was investigated. Rice flours were produced by dry milling and passed through a 200 mesh sieve. Electron microscopy revealed that the structure of SG grains, with round starch granules, possessed larger void spaces than SK and BRC, composed of polygonal starch granules. For this reason, SG grain had low grain hardness and consequently, it was milled to a fine flour with low damaged starch content. The thermo-mechanical properties were determined by Mixolab, which revealed that SG was gelatinised rapidly and maintained high viscosity after gelatinisation. These characteristics gave SG flour the ability to build up bread structure without gluten. Specific volume and crumb hardness of gluten-free rice breads made of SG, SK and BRC flours were 3.37, 3.11 and 2.12 mL g−1 and 2.61, 2.76 and 6.46 N, respectively. The SG flour with round starch structure is appropriate for making gluten-free rice breads.

To investigate the effects of semidry milling method on the quality attributes of glutinous rice flour and sweet dumpling, the glutinous rice flour were prepared by wet, dry and semidry milling, respectively. As a result, the content of damaged starch in dry-milled rice flour was significantly higher than that in wet-milled rice flour (P