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.

Study and Formulation of Composite Flours Based on Gluten Flour and Local Cereal Flours: Fonio, Millet and Sorghum

This study makes it possible to establish baking flours of nutritional quality and technologically acceptable following the increase in their rheological parameters due to the insertion of gluten flour. The composite flours were obtained using the Philips mixer type (model HR2811). The nutritional qualities of the formulated flours were determined by the Kjeldahl, AOAC 985-29, UV-VIS spectrophotometry (DR 5000;HACH and LANGE, France) and Soxhlet gravimetric methods. The compounds obtained are respectively: Protein, carbohydrate, lipid, micronutrient and vitamin contents. Monitoring the analysis of functional properties (water and oil absorption capacity) as well as baking value.

Design and Production of Infant Flours Based on Pumpkin Pulp Enriched with Cakes Extracted from Its Seeds

The inclusion of composite flours in infant food at weaning time should be a priority for mothers. The aim of this project is to formulate infant flour based on pulp flour enriched with oilcake from these grains after extraction of the oil. To do this, the elements were combined to obtain a regulatory formulation. Micro- and macronutrients, minerals, vitamins and tasting of the prepared porridge were determined. The results obtained were satisfactory. The moisture content of the fruit pulp was determined using oven-drying techniques: 92.2%, carbohydrates 6.00%, lipids 0.3%, ash 0.80%, proteins 1.10%, calcium 19.8%, phosphorus 42.6% and iron 0.4%. Furthermore, the carbohydrate content of flours composed of 5% insertion is 62.9 g to 48.8 g per 100 g, and the protein content of compound flours with 5% insertion is 15.9 g to 28.25 g per 100 g. On the other hand, the vitamin C and E contents of fresh pulp and oilcake are 25 mg, 13 mg and 21 mg respectively. However, only copper and β-carotene from 5% to 30% insertion remain invariant to the different insertion rates, with a value of 25 mg for copper and 0 µg for β-carotene. In addition, a variation in the degree of swelling of weaning flours compared with the standard from 3.95% at 5% insertion to 3.58 at 30% insertion was observed. The solubility of flours increases on the one hand with increases in the degree of insertion of the cakes. Flour formulated so many toward basicity. But the presence of traces of oil containing fatty acids can reduce this basicity. This study may be an alternative of industrial flours in infant nutrition.

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.

Assessment of the Aflatoxin Content of Maize Flours Produced in the Commune of Ouagadougou, Burkina Faso

Aflatoxins are toxic metabolites present in various foods, especially when production and conservation do not respect good hygiene practices (GHP). In Ouagadougou, maize flour is produced and sold in different structures by actors who do not always respect GHP. Thus, it is necessary to regularly control the quality of these flours. So, this is carried out with the aim to assess the aflatoxin content of maize flours produced in the municipality of Ouagadougou. For this, twenty-eight (28) samples were collected from households, markets and supermarkets in the city of Ouagadougou. Thus, LC/MS/MS analysis was used to assess the aflatoxin content of the samples. The results obtained reveal the presence of total aflatoxins (AFT) in 78.57% of samples analyzed with levels ranging from 0.89 to 64.25 μg/kg. The prevalence of different types of aflatoxins were 57.14% for aflatoxin B1 (AFB1), 46.43% for aflatoxin B2 (AFB2), 42.86% for aflatoxin G1 (AFG1) and 4.6% for aflatoxin G2 (AFG2). The results also show that 80% and 60% of market samples, 70% and 30% of household samples and 37.5% and 25% of supermarket samples do not comply with European Commission standards for AFT and AFB1 respectively. For all the samples, 60.71% and 42.86% of the samples are compliant according to the limits established by the European Commission (EC) respectively for AFB1 and AFT. Regarding the results obtained, producers and processors must be supervised and trained in GHP for the production of better-quality flours.

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.

Availability, Accessibility and Contribution of Infant Flours to the Diet of Children Aged 6-59 Months in Benin

This study assesses the nutritional composition as well as the availability and affordability of infant flour found on the market and in the households of Benin. To do that assessment, a two-step cross-sectional survey based on food ethnography methods was used. A total of 61 marketplaces were visited in seven towns and rural districts as part of the availability and affordability survey, while 400 children (aged 6 to 59 months) were surveyed to track the uses of infant flours at the household level. The results obtained reveal that pre-manufactured infant flour is sold more in urban areas (Cotonou, Porto-Novo and Parakou) than in rural ones. The average infant flours price did not vary (p = 0.985) in any given year (regardless of abundance or lean periods) nor does it vary (p = 0.133) from one point of sale to another (drugstore or supermarkets). However, the average price is found to be expensive considering the purchasing power of the households surveyed. On the other hand, the amount of ingredients used in the production of the flour types found on the market complies with the recommendations of the Codex Alimentarius, unlike the homemade ones. Pre-manufactured infant flour is found to be outside of the economic reach of most households (92%) who rely heavily on the homemade ones to feed their children. In light of the above, public authorities should help improve geographic access and pricing affordability to quality infant flour for low-income households in urban and remote areas. Moreover, awareness should be raised among mothers relative to the importance of complementary feeding through education on good nutrition practices.

Occupational exposure to flour dust among bakery workers:prevalence,potential hazards and promising interventions

Occupational exposure to flour dust within bakery environments presents significant health hazards to bakery personnel.Flour dust,generated as a byproduct during baking,becomes airborne during the baking process,thus constituting a respiratory threat.Adverse health consequences include respiratory diseases,skin irritation,allergic reactions,and potential long-term health impacts.Data indicates that a broad segment of bakery workers encounters exposure to flour dust,with specific subgroups,such as bakers and dough mixers,being particularly susceptible.Contributing factors to this exposure encompass insufficient ventilation and a lack of awareness.It is vital to assess exposure levels through air quality monitoring and health surveillance.Efficient interventions encompass engineering solutions(e.g.,ventilation systems,dust extraction),administrative measures(including training and the use of personal protective equipment),and the implementation of occupational health and safety programs.Collaborative efforts with healthcare professionals and regulatory authorities are paramount for achieving success.Case studies underscore the effectiveness of such interventions,resulting in improved worker health,thus underscoring the advantages of protective measures.Challenges in this endeavor include industry resistance to change,financial considerations,and issues related to compliance.Future recommendations entail further research,policy enhancements,and the involvement of industry stakeholders and labor unions in advocating for worker safety.

马铃薯全粉和小麦粉对莜面面团水分的影响

为了探索马铃薯全粉和小麦粉对莜面面团水分的影响,以马铃薯全粉和小麦粉及莜面为原料,运用低场核磁共振法(NMR)测试莜面面团中水分的分布及形态,通过改变马铃薯粉和小麦粉的添加比例探究马铃薯全粉和小麦粉对莜面面团中的紧密结合水、弱结合水和自由水的影响,以期为莜面面团在面制品中的深化研究和运用提供可靠数据。NMR对结果的解析表明,①随着马铃薯全粉添加量的增加,导致弱结合水向自由水转化。当莜面与马铃薯雪花粉的比例为6∶4时,自由水A22上升到最大值,为50.42%,弱结合水下降到最小值为42.02%。②随着小麦粉添加量的增加,致使弱结合水向紧密结合水转化,当莜面与中筋粉的比例6∶3时,紧密结合水所占比例最大,为14.25%;当莜面与高筋粉的比例6∶5时,紧密结合水所占比例最大,为20.38%。③随着小麦粉添加种类的变化,导致自由水向结合水转化。因此,马铃薯全粉、小麦粉、小麦不同种类的添加均能改变面团的水分状态与分布。

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。

魔芋凉粉的配方及工艺优化

选用红薯淀粉和魔芋粉为主要原料,以感官评分及质构参数为实验指标,通过单因素试验考察红薯淀粉添加量、魔芋粉添加量、加热温度、加热时间对产品感官及质构的影响,并选择正交试验来优化魔芋凉粉的配方及工艺.结果表明,产品的最佳配方为(以产品质量计):红薯淀粉16 g/100g、魔芋粉0.5 g/100g、纯净水83.5 mL;最佳工艺条件为:加热温度为100℃、加热时间为11 min.该条件下制备的凉粉产品质地细腻,表明光滑,弹性好,不粘牙,质构特性较好,综合评分为87.4分.

湿热处理对豆粉营养品质及面团物化特性的影响

采用湿热处理研究不同豆粉抗氧化、营养特性及面团性质的影响。结果表明:随着湿热处理时间的延长,红豆粉和豌豆粉的总酚、黄酮含量及其抗氧化能力呈先增加后降低的趋势,分别在0.5 h和1.0 h时达到最大,而白芸豆粉总酚、黄酮含量呈增加趋势,在8.0 h达到最大;湿热处理对2,2’-联氮双-(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基清除率和1,1-二苯基-2-三硝基苯肼自由基清除率趋势与总酚、黄酮含量一致;3种豆粉的主要脂肪酸种类分别为棕榈酸、硬脂酸、亚油酸、顺-11-二十碳一烯酸和油酸;湿热处理2.0 h及以上,对白芸豆粉中油酸、亚油酸和顺-11-二十碳一烯酸含量有显著影响;湿热处理后红豆粉和白芸豆粉中游离氨基酸参与美拉德反应,含量显著下降,而豌豆粉中更多结合态的氨基酸游离出来,使其含量升高;扫描电子显微镜观察微观结构结果显示,随着湿热处理时间延长,蛋白质变性和部分淀粉发生糊化,出现孔洞、黏附等现象;淀粉的重结晶使得豆粉的峰值黏度、谷值黏度和回生值下降,抗剪切力变差;面团水分分布测定结果显示,湿热处理后红豆粉的弛豫时间T_(21)、T_(22)增加,红豆粉成团性优于其他面团;湿热处理使混合豆粉热机械特性中的蛋白弱化度增强,抑制了淀粉的回生,降低了老化度,有益于提升产品品质。

基于离散元法的面粉颗粒接触参数标定试验

为设计和优化面粉输送设备,应用离散元法对面粉进行准确地工程建模和分析,需要对其接触参数进行必要的标定。该研究依据颗粒缩放理论,用“Hertz-Mindlin with Johnson-Kendall-Roberts”接触模型表征面粉颗粒间黏性的影响,提出了一种基于静/动态休止角的接触参数标定方法。运用正交试验方法,对接触参数的敏感性和方差分析,表明面粉颗粒间的滚动摩擦系数、面粉颗粒与不锈钢表面间的静摩擦系数、表面能对静态休止角的影响极显著(P<0.01),并且多组接触参数都可以模拟出与试验相同的静态休止角。进一步研究表明,面粉颗粒与不锈钢表面间的静摩擦系数的合理取值范围为0.2~0.4。通过2种填充率、4种转速下基于动态休止角的参数标定,将其中与试验最为吻合的一组参数作为标定结果,其值如下:面粉颗粒之间恢复系数为0.6、面粉颗粒之间静摩擦系数为0.2、面粉颗粒之间滚动摩擦系数为0.1、面粉颗粒与不锈钢容器表面之间恢复系数为0.6、面粉颗粒与不锈钢容器表面之间静摩擦系数为0.6、面粉颗粒与不锈钢容器表面之间滚动摩擦系数为0.5、表面能为0.12 J/m^(2)。使用该组参数对矩形容器中物料自由坍塌试验进行仿真,其结果与试验结果相符,验证了该标定方法的有效性。该研究提出的标定方法简单、易执行,对粉料输送设备的设计及优化具有一定的工程应用价值。

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。

甘薯生全粉添加量对馒头制作工艺及品质的影响

以甘薯-小麦混粉为原料,探究甘薯生全粉馒头制作配方工艺以及甘薯生全粉添加量对馒头基本成分和物化特性的影响。结果表明,甘薯馒头制作配方最优工艺为甘薯生全粉添加量30%、加水量55%、α-淀粉酶添加量0.02%、普鲁兰酶添加量0.75%,此时甘薯生全粉馒头感官评分最高为84.9。随着甘薯生全粉添加量增加,甘薯馒头淀粉和总膳食纤维含量逐渐增大,蛋白质含量逐渐减小,可溶性糖呈不规律变化趋势且变化幅度较小。随着甘薯生全粉添加量增加,甘薯馒头色度WH值、比容逐渐减小,硬度和胶黏性逐渐增加,黏性、回复性、黏聚性和弹性逐渐减小。随着甘薯生全粉添加量增加,冻藏后复蒸馒头比容逐渐减小,硬度逐渐增大;在相同添加量的情况下,随着冻藏时间的延长,比容呈逐渐减小的变化趋势,硬度呈逐渐增大的变化趋势。综上所述,适当添加甘薯生全粉可制作出品质较好的馒头。

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。

紫色马铃薯糕加工工艺参数优化

以低筋面粉和紫色马铃薯为主要原料制作紫色马铃薯糕,采用单因素和正交试验优化紫色马铃薯糕的最佳加工工艺参数,并以感官评分为指标,对该工艺参数下制作的紫色马铃薯糕进行客观评价。结果表明,制作紫色马铃薯糕的最佳工艺参数为紫色马铃薯与低筋面粉总重200 g,其比例35∶65,绵白糖添加量35 g,酵母粉添加量1.5 g,蒸制时间20 min。该工艺条件下制作的紫色马铃薯糕色泽艳丽且均匀,呈天然紫色,松软有弹性,外形完整饱满,口感细腻,富含花青素,具有较高的营养价值,适合婴幼儿及中老年人食用,极大丰富了糕点类食物的市场多样性,具有较高的推广价值。

微波催化面粉发酵效应研究

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全麦粉是指几乎含有小麦籽粒所有成分的面粉,近年来在国内外得到了广泛研究。全麦粉保留了麸皮中的大量维生素、矿物质、膳食纤维,且营养价值高于精白面粉。然而,全麦粉或全麦食品存在适口性差、加工品质差、贮藏稳定性差等问题,限制了其推广应用。该文对全麦粉及全麦食品的发展现状及趋势进行综述,并对全麦食品的发展前景进行展望。