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.

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.

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.

Edible Films of Blended Cassava Starch and Rice Flour with Sorbital and Their Mechanical Properties

In this study, the mechanical properties （tensile strength, elongation at break and folding resistance） of edible biopolymer film blends formed from blended cassava starch and rice flour at different compositions with sorbital used as a plasticizer. A suitable ratio of cassava starch and rice flour to water at 10% w/v was used to form a film solution. The addition of a plasticizer agent up to 30% w/w of blending compositions improved the mechanical properties of the generated films. The mechanical properties of the edible blended films with 30% plasticizer were strongly dependent on the blending compositions. Our results pointed out that the cassava starch and rice flour films at a ratio of 70：30 with sorbitol 30% （w/w） had the highest tensile strength which related to folding endurance of the films.

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）.

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.

Effect of Malva Nut Gum on Pasting Characteristics and Freeze-thaw Stability of Commercial Wheat, Rice or Waxy Rice Flour

The objective of this research was to investigate the effect of Malva nut gum （MG） replacement on the pasting characteristics and freeze-thaw stability of wheat, rice or waxy rice flours. Pasting properties and freeze-thaw stability of different flours incorporated with 0, 0.5%, 1%, 2%, 3% and 5% of MG were investigated. Pasting temperature （60 ℃-87 ℃） of the pastes significantly decreased with increasing of MG content for wheat and rice flours, but had no significant effect for waxy rice flour. Incorporation of MG into all flours significantly elevated the peak viscosity by about 0.9-2.6 folds when compared to non-MG samples. Hot paste viscosity, breakdown and final viscosity for all flour mixtures significantly increased with increasing of MG which ranged from 81-427, 37-559 and 152-463 RVU, respectively. Freeze-thaw stability measurement demonstrated that higher level of MG in wheat and rice gel mixtures could decrease syneresis. However, MG had no effect on syneresis of waxy rice gel. Presence of MG in flours alters the pasting properties and syneresis effect. It is suggested that higher viscosity and lower syneresis of gels could be modified by MG.

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。

大米品种对婴幼儿米粉理化品质的影响

为探究更适宜婴幼儿米粉加工的原料及不同品种大米对米粉品质的影响,以10种优质稻(籼米和粳米各5种)为原料,经滚筒干燥加工成婴幼儿米粉,测定原料米及米粉的理化特性、米粉品质等指标,分析大米品种对婴幼儿米粉品质的影响。结果表明,不同样品的理化品质和微观结构存在显著差异,籼米和粳米加工成的婴幼儿米粉各有优缺点。经过滚筒干燥制备的不同米粉样品水分含量均比原料米下降30%以上,而总淀粉和直链淀粉含量均有所增加。所有米粉样品中RDS占比最大,其中籼米创宇9号和粳米圆粒9031加工的米粉RDS占比均达到82%以上,且RDS含量高的米粉,水溶性也较高。综合米粉热特性、糊化特性、流变特性、扫描电镜图像等理化品质,籼米创宇9号和粳米圆粒9031加工的婴幼儿米粉品质较好。

糯米粉品种对湿法速冻汤圆品质的影响

为探究不同品种糯米原料的粉质特性对采用湿法工艺制得的速冻汤圆品质的影响,选取8种原料糯米,测定其基本组分、糊化特性、热力学特性,以及制得的湿法速冻汤圆的各项品质指标,采用主成分及相关性分析,研究糯米粉特性和湿法速冻汤圆品质的关系。结果表明,第一主成分反映糯米粉的糊化特性和汤圆的质构特性及水分分布,对糯米粉的评价与选择方面起重要作用。糊化温度和硬度呈显著正相关,糊化温度、最终黏度和回复性呈显著正相关。糯米粉中脂肪含量高于0.8%,溶胀指数在10.53~12.65 g/g之间,水溶性指数在16.33%~19.77%之间,糊化温度在71.00~72.97℃之间,峰值黏度在1892.00~2124.33 cp之间,崩解值在834.00~880.67 cp之间,回生值在240.33~248.67 cp之间的糯米品种更适合制作湿法汤圆。结论:8个糯米品种中,越糯碎1号制作的湿法速冻汤圆,具有更理想的口感,品质更加稳定。该结论可为湿法速冻汤圆生产中糯米的选择提供一定理论参考。

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。

冻融和盐作用对糯米粉的结构和糊化特性的影响

糯米浆是我国古代应用最广泛的建筑胶凝材料,可显著提高三合土和灰浆的强度特性、抗渗特性和粘结特性.挖掘糯米浆的科学价值,对于传统技术的科学利用,特别是对古建筑的修复具有十分重要的意义.文中用石油醚对糯米粉进行脱脂,采用双波长法对糯米粉中的直链淀粉和支链淀粉进行测定,用FT-IR,XRD,TG/DTG和SEM分析了糯米粉脱脂前后的结构和形貌,同时用XRD和SEM分析了冻融循环、Na 2SO 4加入对糯米淀粉结构、晶型和形貌的改变,用Brabender粘度仪研究了不同条件下的糊化特性.结果表明,糯米粉中直链淀粉和支链淀粉的含量分别为9.16%和78.56%,糯米粉和脱脂糯米粉的糊化温度基本相同,但峰值粘度、崩解值和回升值下降.冻融循环不会改变糯米粉中淀粉颗粒的结构和晶型,但峰值粘度、谷值粘度、终值粘度、崩解值和回升值均有降低趋势;加入4%的Na 2SO 4后,会使糊化温度升高,崩解值升高,回升值下降.本研究对糯米粉的科学认知具有重要的意义,期望为针对性地提高糯米浆的胶凝品质提供理论参考.

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。

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。

不同制粉方式对米粉粉质和鲜湿米线品质的影响

为探究不同制粉方式对米粉粉质及其鲜湿米线品质的影响,采用干法、半干法和湿法制粉并制作鲜湿米线,分析了米粉基本组分、破损淀粉含量、粒径分布、颗粒表观形态、溶解度、膨润力和糊化特性,比较了鲜湿米线的质构、蒸煮和感官品质。结果表明,干法冲击300目粉破损淀粉含量最高(17.55%),粒径最小,溶解度最大,峰值粘度、最终粘度、回生值最小;湿法粉的破损淀粉含量最低(2.87%),其溶解度最小,峰值粘度、最终粘度、回生值最大;随着调质水分含量的升高,半干调质粉的破损淀粉含量降低(4.49%→3.55%),粒径减小,溶解度变小。扫描电镜显示破损淀粉含量越小,米粉的颗粒表观形态也更完整。湿法粉制作的鲜湿米线品质最好,干法粉不适合制作鲜湿米线,半干调质33%粉和半干浸泡粉制作的鲜湿米线品质接近湿法粉,在实际生产中可以考虑用这两种半干粉部分或完全替代湿法粉。研究结果为我国米线传统加工工艺的革新提供参考。

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。

差异化蛋白脱除对早籼米粉性质的影响

[目的]探究差异化脱蛋白对米粉理化功能性质的影响机制。[方法]采用酶法、碱法对米粉进行差异化蛋白脱除,并对脱蛋白米粉的破损淀粉含量、粒径分布、颗粒表观形态、溶解度、膨润力、糊化特性及质构特性进行分析。[结果]蛋白凝胶电泳(SDS-PAGE)和激光共聚焦(CLSM)结果表明,碱法是等比例脱除各蛋白亚基,而酶法对淀粉颗粒表面蛋白脱除的均一性更好;原粉粒径分布的主峰大约在70μm处,而脱蛋白米粉的主峰则向左偏移至6μm处;随着蛋白含量的降低,脱蛋白米粉的破损淀粉含量呈下降趋势,而弹性、硬度显著升高,其中酶法3%米粉的粒径分布最为均一,D90最小(23.58μm),破损淀粉含量也由原粉的3.32%降低至1.48%,而弹性和硬度相比原粉分别提高了54.55%,52.60%;与原粉相比,脱蛋白米粉具有较低的峰值黏度、崩解值和最终黏度,其中酶法3%米粉的崩解值和回生值均最小,说明其热糊稳定性最好,且不易回生。[结论]碱法和酶法均能有效脱除蛋白,提升早籼米粉的粉质特性,相比之下酶法处理条件更加温和,蛋白和粒径分布更加均一,抑制回生效果更明显。