Effects of Milling Methods on Rice Flour Properties and Rice Product Quality:A Review

High-quality rice flour is the foundation for the production of various rice-based products.Milling is an essential step in obtaining rice flour,during which significant changes occur in the physicochemical and quality characteristics of the flour.Although rice flour obtained through mainstream wet milling methods exhibits superior quality,low production efficiency and wastewater discharge limit the development of the industry.Dry milling,on the other hand,conserves water resources,but adversely affects flour performance due to excessive heat generation.As an emerging powder-making technique,semi-dry milling offers a promising solution by enhancing flour quality and reducing environmental impact.This is achieved by minimizing soaking time through hot air treatment while reducing mechanical energy consumption to reach saturated water absorption levels.However,continuous production remains a challenge.This comprehensive review summarizes the effects of various milling technologies on rice flour properties and product qualities.It also discusses key control indicators and technical considerations for rice flour processing equipment and processes.

Preparation of lactic acid bacteria compound starter cultures based on pasting properties and its improvement of glutinous rice flour and dough

The effects of 5 lactic acid bacteria(LAB)fermentation on the pasting properties of glutinous rice flour were compared,and suitable fermentation strains were selected based on the changes of viscosity,setback value,and breakdown value to prepare LAB compound starter cultures.The results revealed that Latilactobacillus sakei HSD004 and Lacticaseibacillus rhamnosus HSD005 had apparent advantages in increasing the viscosity and reducing the setback and breakdown values of glutinous rice flour.In particular,the compound starter created using the two abovementioned LAB in the ratio of 3:1 had better performance than that using a single LAB in improving the pasting properties and increasing the water and oil absorption capacity of glutinous rice flour.Moreover,the gelatinization enthalpy of the fermented samples increased significantly.For frozen glutinous rice dough stored for 28 days,the viscoelasticity of frozen dough prepared by compound starter was better than that of control dough,and the freezable water content was lower than that of control dough.These results indicate that compound LAB fermentation is a promising technology in the glutinous rice-based food processing industry,which has significance for its application.

Effect of Glutinous Rice Flour on Mechanical Properties and Microstructure of Cement-based Materials

The mechanism of glutinous rice flour,a kind of natural admixture,on the hydration process,setting time,and microstructure of the Portland cement was investigated.The experimental results show that the glutinous rice flour has an obvious setting retarding effect on cement pastes.The optimal dosage of the glutinous rice flour is 3wt%.In this case,the initial and final setting time of the paste are delayed by 140 and185 min,respectively.The flexural and compressive strengths of the hardened paste are increased by 0.35%and 0.07%after 56 d of curing.The glutinous rice flour hinders the mineral dissolution process and decreases the concentration of calcium ion at the initial stage of hydration due to the complexation effect,thereby hindering the nucleation and growth of CH and C-S-H phases and prolonging the hydration process.However,C-S-H phases combine with the glutinous rice flour to contribute the bonding effect together,which compacts the microstructure of hardened cement pastes at the later hydration stage of cement pastes.Thus,in-depth investigation on the utilization of glutinous rice flour as the admixture for the Portland cement is expected to be meaningful for the control of hydration exothermic rate and setting time.

Functional properties,antioxidant activity and in-vitro digestibility characteristics of brown and polished rice flours of Indian temperate region

The present investigation was aimed to study functional properties,antioxidant activity and in-vitro digestibility characteristics of brown and polished flours obtained from four rice cultivars(SR-4,K-39,Mushq Budij and Zhag)of Kashmir.Brown rice flours had higher total dietary fibre(3.08%-3.68%),oil absorption(116.0%-139.0%),emulsion capacity(4.78%-9.52%),emulsion stability(87.46%-99.93%)and resistant starch content(6.80%-9.00%)than polished flours.However,polished flours presented greater water absorption(102.0%-122.0%),foaming capacity(8.00%-13.63%),apparent amylose(19.16%-22.62%),peak(2260.0-2408.0 cP),trough(1372.0-1589.0 cP)and breakdown(714.0-978.0 cP)viscosities than their brown counterparts.Brown rice flours depicted highest total phenolic content(4.40-6.40 mg GAE/g)and inhibition of lipid peroxidation(19.50%-33.20%).However,equilibrium starch hydrolysis percentage(C∞)and predicted glycemic index of brown rice flours were lower than their polished counterparts.Among rice cultivars,brown Zhag flour had the highest total dietary fibre(3.68%),emulsion capacity(9.52%),emulsion stability(99.93%),resistant starch(9.00%),DPPH radical scavenging activity(85.45%)and inhibition of lipid peroxidation(33.20%),respectively.Emulsion capacity and emulsion stability were positively correlated with protein content of rice flours.However,peak,trough,breakdown and setback viscosities were negatively correlated with protein and fat contents of rice flour.The present investigation will be helpful in identifying nutritive role of rice flours from studied cultivars in human diet.

Effects of Dry-Milling and Wet-Milling on Chemical, Physical and Gelatinization Properties of Rice Flour

Rice flour from nine varieties, subjected to dry- and wet-milling processes, was determined for its physical and chemical properties. The results revealed that milling method had an effect on properties of flour. Wet-milling process resulted in flour with significantly lower protein and ash contents and higher carbohydrate content. Wet-milled flour also tended to have lower lipid content and higher amylose content. In addition, wet-milled rice flour contained granules with smaller average size compared to dry-milled samples. Swelling power at 90℃ of wet-milled samples was higher while solubility was significantly lower than those of dry-milled flour. Dry milling process caused the destruction of the crystalline structure and yielded flour with lower crystallinity compared to wet-milling process, which resulted in significantly lower gelatinization enthalpy.

Optimization of Bread Preparation from Wheat Flour and Malted Rice Flour

The feasibility of partially replacing wheat flour with malted rice flour in bread making was evaluated in several formulations, aiming to find a formulation for the production of malted rice-wheat bread with better nutritional quality and consumer acceptance. The whole grains of a local rice variety （Oryza sativa L. subsp. indica var. Mottaikaruppan） were steeped in distilled water （12 h, 30°C） and germinated for 3 days to obtain high content of soluble materials and amylase activity in bread making. The quality of bread was evaluated by considering the physical and sensorial parameters. When the wheat flour was substituted with malted rice flour, 35% substitution level and the malted rice flour from 3 days of germination was the best according to the physical and sensory qualities of bread. The quality of bread was improved by the addition of 20 g of margarine, 20 g of baking powder and 20 g of yeast in 1 kg of flour. Among different ratios of yeast and baking powder, 2：1 was the best. Bread improver containing amylases and oxidizing agents at the concentration of 40 g/kg was selected as the best concentration. When comparing the final formulation made in the bakery with wheat bread, malted rice-wheat bread contains more soluble dietary fiber （0.62%）, insoluble dietary fiber （3.95%）, total dietary fiber （4.57%） and free amino acid content （0.64 g/kg） than those in wheat bread （0.5%, 2.73%, 3.23% and 0.36 g/kg, respectively）.

Optimization of High-Protein Glutinous Rice Flour Production Using Response Surface Method

A response surface method was employed to study the effect of α-amylase concentration, hydrolysis temperature and time on the production of high protein glutinous rice flour(HPGRF). The suspension of glutinous rice flour(15%) that contained 6.52% protein was gelatinized and subsequently hydrolyzed by thermostable α-amylase. The hydrolysis yielded 0.144–0.222 g/g HPGRF with 29.4%–45.4% protein content. Hydrolysis time exerted a significant effect, while enzyme concentration and hydrolysis temperature showed insignificant effect on the protein content and production yield of HPGRF. The result of response surface method showed that the optimum condition for the production of HPGRF that contained at least 36% protein was treating gelatinized 15% glutinous rice flour suspension with 0.90 Kilo Novo α-amylase Unit(KNU)/g α-amylase at 80 oC for 99 min. By carrying out the predicted hydrolysis condition, HPGRF with 35.9% protein and 61.8% carbohydrates was resulted. The process yielded 0.172 g/g HPGRF. HPGRF contained higher amount of essential amino acids compared to glutinous rice flour. HPGRF had higher solubility and lower swelling power, and also showed no pasting peak compared with glutinous rice flour.

The Effect of Rice Flour for Amelioration of Sleeping in Social Isolated Mice

In an era where the health-damaging effects of wheat flour (gluten) are increasingly recognized, rice flour has become an important alternative for many people, yet its psychophysiological effects remain largely unknown. Here, we report the potential beneficial effects of rice flour for sleep disturbances in stressed mice. Four-week-old male ddY mice were reared in social isolation for 4 weeks. The control group was reared in a social group. Rice flour was given orally in food to isolated mice at a dose of 2.5 w/w% and 5.0 w/w% for 4 weeks from the start of isolation rearing. MF food was given to the control group. Pentobarbital-induced (40 mg/kg, i.p.) time to sleep induction and righting reflex was measured to determine the effects of rice flour on sleep behavior. Blood samples were obtained after the experiments, and serum corticosterone was measured. Sections from the prefrontal cortex and the brainstem were isolated to measure serotonin, dopamine and interleukin (IL)-6 concentrations. We found that the administration of rice flour dose-dependently improved time to sleep and reduced sleep time in socially isolated mice. Blood corticosterone concentrations, which increased after isolation stress, were decreased after the administration of rice flour. Serotonin and dopamine concentrations in the prefrontal cortex which decreased after isolation stress improved after the administration of rice flour. Brainstem IL-6 concentrations increased after isolation stress, but decreased dose-dependently after rice flour administration. Our results suggest that rice flour reverses sleep disturbances in mice induced by social isolation.

Influence of replacement of wheat flour by rice flour on rheo-structural changes, in vitro starch digestibility and consumer acceptability of low-gluten pretzels

This study aimed to access the influence of rice flour incorporation on various quality attributes of low-gluten wheat-based pretzels viz., functional, rheological, starch digestibility, color, textural and sensorial properties. Significant increase in swelling power (18.33 ± 0.51) and bulk density (0.58 ± 0.04) was observed in flour blend upon incorporation of rice flour, whereas, significant decrease in oil absorption capacity (0.62 ± 0.09), solubility index (6.72 ± 0.17), foaming capacity (9.67 ± 0.34), and foaming stability (3.39 ± 0.15) was recorded. Pasting properties of samples were studied using a Rapid Visco Analyser which indicated that all the pasting properties increased with an increase in rice flour incorporation. Fourier transform infrared spectroscopic studies revealed no difference in the basic functional groups of flour blend upon the incorporation of rice flour, however, it had a pronounced effect on elastic modulus (G′) of flour blend. In vitro starch digestion characteristics revealed 7.23% surge in slowly digestible starch and 13.36% reduction in rapidly digestible starch of developed low-gluten pretzels upon the incorporation of rice flour. Apparent amylose content (27.3 ± 1.45) and resistant starch content (6.12 ± 0.97) increased and starch digestibility index (69.87 ± 1.72) decreased in developed low-gluten pretzels. In conclusion, the developed low-gluten pretzels had significantly (p < 0.05) higher mineral profile and lightness (L*) and lower breaking strength in addition to having better overall acceptability. This study indicated that substituting wheat flour with rice flour up to a level of 35% affected the quality attributes of developed low-gluten pretzels.

超声协同大豆分离蛋白对米粉和米面包品质的影响及机制研究

目的探究超声协同大豆分离蛋白(soybean isolate protein,SPI)对米粉以及米面包品质的影响。方法以碎米为主要原料,5个梯度(0%、3%、6%、9%、12%,以碎米粉质量计)的大豆分离蛋白(soybean isolate protein,SPI)为辅料,比较超声协同5个梯度SPI对混合粉热机械学特性、糊化特性、流变特性以及米面包比容、损耗率、感官评价的影响。结果与未进行超声处理的样品相比,超声协同SPI处理的米粉的吸水率从64.90±0.00增加至94.80±0.00,其混合粉的峰值黏度从2704.00±47.76降低至1567.00±116.73,表明超声使淀粉部分支链断裂,生成大量短直链淀粉,导致分子量下降,相互作用减弱;超声处理后的样品储能模量(G')曲线随着SPI含量的增加呈现出先降低后增加再降低的趋势,损耗模量(G")曲线呈现出逐渐降低的趋势。当SPI添加量为9%时,米面包的比容达到最大值,为(0.86±0.08)mL/g,感官评分从50.05±3.75增加至86.27±2.28;当SPI添加量达到12%时,米面包的损耗率达到最低。结论综上所述,采用9%SPI的方法制备米面包,可以有效地改善米面包品质,本研究为米面包在食品领域的应用提供了理论基础。

超声波处理糯米粉制作的麻糬特性研究

为了评价超声波处理的糯米粉在实际食品中的应用效果,以超声波处理(功率130 W,料液比1∶2 g/mL,时间20 min)的糯米粉(ultrasound treated waxy rice flour,UT-WRF)和原糯米粉(native waxy rice flour,N-WRF)为原料制作麻糬,分析并比较麻糬特性。结果表明:与以N-WRF为原料制作的麻糬(mochi prepared by native waxy rice flour,N-Mochi)相比,以UT-WRF为原料制作的麻糬(mochi prepared by ultrasound treated waxy rice flour,UT-Mochi)更加爽滑不粘牙,柔软而富有弹性,评分更高且更加明亮剔透;经扫描电子显微镜观察到UT-Mochi的表面孔径较小且大小较为均一;UT-Mochi的表观黏度、拉伸断裂力和最大拉伸距离均高于N-Mochi,储能模量、硬度和咀嚼性均低于N-Mochi;UT-Mochi中的可冻结水含量、横向弛豫时间和峰面积均低于N-Mochi,其水分分布更分散。经超声波处理的糯米粉制作的麻糬在外观、质构以及感官方面得到明显改善。

基于模糊数学感官评价法优化营养复配预熟糙米粉配方工艺

该研究以微波冻干处理后的发芽糙米粉为原料,以吸水指数和水溶指数结合模糊数学感官评分为指标,研究黑豆粉、抗性糊精和赤藓糖醇的添加量对营养复配预熟化发芽糙米粉品质的影响,并对复配发芽糙米粉的营养特性、卫生指标和贮藏稳定性进行分析。研究结果表明,营养复配发芽糙米粉的最优配方为黑豆粉添加量20%、抗性糊精添加量8%、赤藓糖醇添加量4%。复配糙米粉营养价值提高,卫生指标符合国家标准,在贮藏120 d后新鲜度变差但仍高于原粮糙米。

近代福建洋粮进口述析

明代中期之后,福建部分地区出现粮食短缺,清代缺粮益发严重。鸦片战争以降,福建农村经济作物快速增长排挤了粮食生产,城市化引起粮食需求量增加,全国粮食供求格局发生变化等多重因素的交互影响,福建洋米、洋面、洋麦输入数量逐渐增加。据估算,1889—1936年,福建年均输入洋米大约90万担、洋面26万担左右,加上少量洋麦,三者合计约120万担左右。虽然洋粮对弥补福建民食具有一定作用,但是资金外流加重外贸入超,从而引发社会各界人士的忧虑,于是1933年10月4日福建省政府宣布对洋米征税。

紫薯粉对米粉食用品质和理化特性的影响

该研究制备了不同紫薯粉添加量对米粉食用品质和理化特性的影响。结果表明,相较于0%添加量(以早籼米质量计,下同),5%~25%添加量(质量分数,下同)紫薯米粉的花色苷、总酚含量分别增加了61.79%~223.58%、38.64%~89.77%,血糖生成指数值降低至61.89。随紫薯粉添加量的增加,紫薯米粉的糊化起始温度(To)、峰值温度(Tp)、终止温度(Tc)逐渐升高,而热焓值(ΔH)逐渐降低。当添加量由0%增加至15%时,米粉的蒸煮损失率、断条率分别由13.49%、24.77%下降至9.65%、18.65%,食用品质逐步提升;当添加量继续增加至25%时,米粉的蒸煮损失率、断条率分别达到12.71%、27.71%,米粉品质下降。综上所述,添加量为15%时,紫薯米粉色泽均匀,色彩艳丽,食用品质及理化特性最佳。

糙米粉挤压改性工艺优化及其特性分析

以糙米为主要原料,采用挤压技术改性糙米粉。以糊化度为指标,在单因素试验的基础上通过响应面法优化改性工艺,并对改性前后糙米粉的特性进行分析。结果表明:最佳改性工艺参数为物料粒度120μm、水分添加量32%(以糙米粉质量计)、螺杆旋转频率30 Hz、挤压温度120℃,在此条件下改性糙米粉糊化度达到93.17%。与改性前相比,改性糙米粉水分、脂肪、淀粉和蛋白质含量降低;维生素B_(1)和B_(2)含量略降低。特性分析结果表明,改性后糙米淀粉颗粒表面变得平整,结晶度下降。

超声处理对黑米粉结构、理化及消化性的影响研究

为探究超声处理对黑米粉结构、理化及消化性的影响。以黑米粉(BRF)为研究对象,分析不同超声功率处理对黑米粉粒径分布、微观结构、结晶结构、短程有序结构、热力学、流变学和消化特性的影响。结果表明:超声处理后黑米粉颗粒被破坏,粒径减小,淀粉结晶度从45.14%降至28.53%,短程有序结构受到破坏。在理化性质方面,黑米粉吸水指数、冷水溶解度和膨胀度显著增加,分别从2.02 g/g、4.86%、3.20%上升至4.27 g/g、10.5%、6.17%。超声处理后黑米粉的糊化焓和储能模量与损耗模量均降低。在消化性方面,经超声处理后黑米粉的RDS含量减少,SDS和RS含量显著升高。

3D打印糯米粑及参数优化

该研究将小麦粉(wheat flour,WF)和糯米粉(glutinous rice flour,GRF)以不同比例混合,探讨不同质量比的WF/GRF对糯米粑面团结构的影响及其在3D食品打印机中的适用性。结果表明,添加GRF使糯米粑面团中面筋的稳定性和连续性下降,硬度增加、黏附性下降、糊化温度升高、结构更加疏松。其中50:0、42:8和38:12(质量比)的混合比例具有良好的3D打印适应性。当混合比例为42:8(质量比)时,3D打印糯米粑的最佳压缩压力和内部填充率分别为400 kPa和60%,此时生产的糯米粑内部纹理清晰,变形小,分辨率高,与市售糯米粑相比,气味、组织结构和口感上差异不大并且外观更具吸引力。此研究为开发以WF/GRF为基础的个性化3D打印食品奠定理论基础,对3D打印技术在食品工业中的广泛应用具有深远意义。

Physico-chemical properties and structure of rice cultivars grown in Heilongjiang Province of China

The relationships between chemical composition,structure and physicochemical properties such as pasting,thermal,and textural properties of 12 temperate rice cultivars grown in Heilongjiang Province,China were investigated in this study.There were significant differences in the content of fat,protein,ash,amylose,damaged starch among 12 cultivars.Brabender Viscograph results showed that gelatinization time,peak viscosity,pasting and peak temperature ranged from 9 min to 15 min,2100 BU to 2500 BU,58.75℃to 72.00℃and 63.75℃to 84.45℃,respectively,except for the waxy one Longjing 9.To,Tp,Tc andΔH were found in the range of 58.34℃to 67.96℃,65.39℃to 75.38℃,78.47℃to 90.69℃and 2.036 J/g to 3.127 J/g respectively.Scanning Electron Micro-photograph results showed that all starch granules were polyhedral with irregular shapes,except Longjing 9 showing signs of the loss of physical integrity.The hardness,adhesiveness,springiness,gumminess,cohesiveness and resilience ranged from 395.87 g to 1161.76 g,-90.842 g·mm to-36.4 g·mm,0.498 to 0.747,78.631 g to 466.837 g,0.199 to 0.569,0.321 to 0.504,respectively.Correlation studies indicated that amylose,damaged starch,protein,fat and ash played a more important role in determining the rice properties of pasting,thermal,crystallinity and texture.