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.

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.

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.

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.

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.

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.

Preparation of Potato Whole Flour and Its Effects on Quality of Flour Products: A Review

When harvested the potato has a high moisture content, this could make its transportation and storage difficult. To help solve the transportation difficulties, potato is made into whole flour by many food processing companies. Potato whole flour has high nutritional value and may be regarded as beneficial to human health and fitness. In addition to the direct use of potato whole flour,it can also be used as added ingredients into other food products. This study summarizes and analyzes the processing technology of potato whole flour and its application in noodle products.

Proximate, Chemical and Functional Properties of Wheat, Soy and Moringa Leaf Composite Flours

The study presents the effect of utilizing wheat, soy and moringa leaf flour and quality analysis of the flour. The composite flour was prepared using refined wheat flour, soy flour and moringa leaf flour. Four composite flour, compositions were formulated such as 100% wheat flour (control) designated as sample A. Sample B consisted of 75% wheat, 20% soybean and 5% moringa leaf. Sample C consisted of 70% wheat, 20% soybean and 10% moringa leaf. Sample D was 65% wheat, 20% soybean and 15% moringa leaf. Sample E was 60% wheat, 20% soybean and 20% moringa leaf, respectively. Proximate, chemical, and functional properties of wheat, soy and moringa leaf flours were studied in composite flour variation and preparations. The present study highlighted the nutrients enrichment of flour on incorporation of soy and moringa leaf. Relevant statistical tests were done to analyse the significance of means for all tested parameters. Composite flour composition with 20% soybean was identified to produce optimal nutrient, mineral quality and yield. The addition of soybean and moringa flour in baked products has been shown in this study to improve the nutrition and health benefits of the body. It also serves as a good cut on the cost of wheat importation in communities with supply challenges.

Influence of potato flour on dough rheological properties and quality of steamed bread

It is a novel idea to make steamed bread by adding potato flour into wheat flour considering the production and nutritional factors of potato. In this study, the influence of potato flour(0–35%) on dough rheology and quality of steamed bread were investigated. Potato flour addition significantly influenced the dough rheological properties and steamed bread quality, such as increased water absorption, the maximum gaseous release height, total volume of CO_2 and hardness, while decreased dough stability and specific volume of steamed bread. Moreover, correlation analysis suggested that dough height at the maximum development time, dough stability, water absorption and the phase tangent can be used for predicting the technological quality of steamed bread. Potato-wheat steamed bread had higher dietary fibre, ash content and antioxidant activity than those of wheat steamed bread. The estimated glycemic index decreased from 73.63(0%) to 60.01(35%). Considering the sensory evaluation, the steamed bread with 20% potato flour is acceptable. In conclusion, adding appropriate quantity of potato flour to wheat flour for steamed bread production will not only maintain the technological quality, but also can improve the nutritional value of the steamed bread.

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.

Production of microbial medium from defatted brebra(Milletia ferruginea)seed flour to substitute commercial peptone agar

Objective:To investigate and optimize microbial media that substitute peptone agar using brebra seed defatted flour.Methods:Defatted process.inoculums preparation,evaluation of bacterial growth,preparation of cooked and hydrolyzed media and growth turbidity of tested bacteria were determined.Results:Two percent defatted flour was found to be suitable concentration for the growth of pathogenic bacteria:Escherichia coli(ATCC 25922)(E,coli),Pseudomonas aeruginosa(ATCC27853),Salmonella(NCTC 8385)and Shigella flexneri(ATCC 12022)(S.flexneri),while 3%defatted flour was suitable for Staphylococcus aureus(ATCC 25923)(S.aureus).E.coli(93±1)and S.flexneri(524±1)colony count were significantly(P≤0.05)greater in defatted flour without supplement than in supplemented medium.E.coli[(3.72×10~9±2)CFU/mL],S.aureus[(7.4×10~9±2)CFU/mL],S.flexneri[(4.03×10~9±2)CFU/mL]and Salmonella[(2.37×10~9±1)CFU/mL]in non-hydrolyzed sample were statistically(P≤0.05)greater than hydrolyzed one and commercial peptone agar.Colony count of Salmonella[(4.55≤10~9±3)CFU/mL],S.flexneri[(5.40≤10~9±3)CFU/mL]and Lyesria moncytogenes(ATCC 19116)[(5.4×10~9±3)CFU/mL]on raw defatted flour agar was significantly(P≤0.05)greater than cooked defatted flour and commercial peptone agar.Biomass of E.coli,S.aureus.Salmonella and Enterococcus faecalis in non-hydrolyzed defatted flour is highly increased over hydrolyzed defatted flour and commercial peptone broth.Conclusions:The defatted flour agar was found to be better microbial media or comparable with peptone agar.The substances in it can serve as sources of carbon,nitrogen,vitamins and minerals that are essential to support the growth of microorganisms without any supplements.Currently,all supplements of peptone agar are very expensive in the market.

Variation and trends in dough rheological properties and flour quality in 330 Chinese wheat varieties

The objective of this study was to investigate variation and trends in dough rheological properties and flour quality traits in 330 Chinese wheat varieties. The dough rheological properties of development time(DT), stability time(ST), and farinograph quality number(FQN)were evaluated, as well as the flour quality traits of protein(PC), wet gluten content(WGC), and sedimentation value(SV). The coefficients of variation of DT(40.5%), ST(58.1%), and FQN(42.4%) were higher than those of PC(9.1%), WGC(10.1%), and SV(15.3%). Normal distributions were observed for the flour quality indices but not for the rheological parameters. SV was strongly correlated with the three rheological parameters and accordingly might be used as a primary indicator for dough rheological property evaluation. Our results showed that there has been marked improvement in dough rheological properties for Chinese wheat varieties released since 1986, while flour quality has remained stable.

Effects of Preheating Temperature, Moisture and Sodium Metabisulfite Content on Property of Maize Flour Dough

Processing temperature, maze flour particle size, and level of water and sodium metabisulfite were varied during the preparation of maize noodles. Preheated to 90—95 ℃ a mixture of maize flour or meal, water(43%—45% moisture) and salt enabled the preparation of noodles using a pasta extruder. Maize flour with smaller particle size yielded better noodles than did maize meal. The addition of sodium metabisulfite enabled the production of noodles at lower processing temperatures; however, cooking losses increased. Processing maize flour with higher water absorption yielded noodles that required longer cooking time but with decreased losses. The functionalities of starch and protein in raw ingredients and in products were determined. Starch gelatinized and retorgraded during processing maize noodles, as indicated by changes in pasting viscosity curves. Maize proteins contributed to the increased viscosity of dough above 40 ℃. The increased integrity of cooked maize noodles, however, corresponded to the increased amounts of gelatinized and retrograded starch.

Use of two-stage dough mixing process in improving water distribution of dough and qualities of bread made from wheat–potato flour

The two-stage dough mixing process was innovated to improve the qualities of bread made from potato flour(PF) and wheat flour at a ratio of 1:1(w/w). The final dough was first prepared from wheat flour before being added with PF. The effects of the method on enhancing the dough qualities were verified, and the distribution of water in gluten-gelatinized starch matrix of the doughs was investigated. We observed that the bread qualities were improved, as reflected by the increase of specific volume from 2.26 to 2.96 m L g^–1 and the decrease of crumb hardness from 417.93 to 255.57 g. The results from rheofermentometric measurements showed that the dough mixed using the developed mixing method had higher maximum dough height value, time of dough porosity appearance, and gas retention coefficient, as well as enhanced gluten matrix formation compared to that mixed by the traditional mixing method. The results from low-field nuclear magnetic resonance confirmed that the competitive water absorption between gluten and gelatinized starch could restrict the formation of gluten network in the dough mixed using the traditional mixing process. Using the novel mixing method, gluten could be sufficiently hydrated in stage 1, which could then weaken the competitive water absorption caused by gelatinized starch in stage 2;this could also be indicated by the greater mobility of proton in PF and better development of gluten network during mixing.

Application of resistant starch in bread: processing, proximate composition and sensory quality of functional bread products from wheat flour and African locust bean <i>(Parkia biglobosa)</i>flour

Application of resistant starch prepared from parkia flour was produced by replacement of wheat flour with 0, 5%, 10%, 15%, 20%, 30% and 40% Parkia flour. Processing, proximate composition, digestibility of resistant starch in bread and sensory quality were evaluated. Resistant starch was significantly (p < 0.05) increased as Parkia flour level increase in all breads. The resistant starch prepared from Parkia flour was 47.21%. However, wheat bread was 1.47% and Parkia bread 18.52% to 22.28% baked of (200℃ at 45 min) with 2.16% wheat bread and 31.74% to 35.05% Parkia bread baked of (130℃ at 90 min). Supplementation of wheat flour with Parkia flour 0 - 40% increased the crude protein content significantly (p < 0.05) from (7.89% - 15.68%), ash from (0.91% - 2.54%) and crude fiber (1.41% - 4.97%). Color of the bread treatments was remarkably affected by addition of different levels of Parkia flour. Therefore, Parkia flour could be added to wheat flour up to 15% without any observed detrimental effect on bread sensory properties. Sensory evaluation results indicated that bread with 5% to15% Parkia flour were rated the most acceptable and there was no significant difference in terms of acceptability compared to the control. This could be used to improve the nutritional quality of bread especially in developing countries were malnutrition is prevalent.

Relationship between physicochemical characteristics of Korean wheat flour and quality attributes of steamed bread

The purpose of this study is to identify major factors affecting the manufacture and quality of steamed bread,consumed in Southeast Asia including China,Japan,and Korea.Hence,flours of 11 Korean wheat cultivars were used to evaluate quality attributes of two different styles of steamed bread,Korean style steamed bread(KSSB)and northern-style Chinese steamed bread(NSCSB).KSSB prepared more ingredients and higher optimum water absorption of dough than NSCSB because Korean consumers prefer white and glossy surface and soft crumb.KSSB showed lower height,larger diameter and volume of steamed bread,higher stress relaxation,and softer texture of crumb than NSCSB.The correlation between flour characteristics and quality of steamed bread was different in KSSB and NSCSB.About 90%of variability in the height and volume of KSSB could be predicted from protein content,mixing tolerance of Mixograph,average particle size of flour,final viscosity and solvent retention capacity.Protein content and quality parameters also could explain the variation of steamed bread height in NSCSB.Korean wheat carrying Glu-A3c allele produced higher volume of steamed bread(704.7 mL)than Glu-A3d allele(645.8 mL)in KSSB,although there was no significant difference in volume of NSCSB by glutenin compositions.Glu-D1d and Glu-A3c alleles had softer texture of crumb than Glu-D1f and Glu-A3d alleles in KSSB,Glu-B3i allele also showed lower hardness of crumb than their counterpart allele in NSCSB.Hard wheat showed higher height and volume of steamed bread,and lower stress relaxation and hardness of crumb than soft wheat in KSSB.

Effect of Storage Temperature and Periods on Some Characteristics of Wheat Flour Quality

A laboratory experiment has been designed and implemented to study the effects of storage temperatures (27.5°C and 37.5°C) and storage periods (day, 3 days, 10 days, 20 days and 30 days) in normal conditions and relative humidity on the characteristics of wheat flour quality, as well as some of the chemical characteristics of flour (moisture content and ratio of wet gluten), the physical properties (color and falling number). Increasing the storage temperature from 27.5°C to 37.5°C has led to decreasing moisture content of flour stored under storage relative humidity of 38% - 70%. It has also resulted in extending the storage period from 1 day to 10 days to a decrease in moisture content of flour, and this decline has increased the storage period up to thirty days. The overlap between these two factors has been significantly affective. As the storage temperature of flour increased from 27.5°C to 37.5°C, the percentage of wet gluten has been increased too, and the storage period was extended to ten days. This has led to a significant increase in the percentage of wet gluten flour. In addition, there was a significant response to the effective overlap between the storage temperatures and periods of storage under study in this manner. Increasing the storage temperature from 27.5°C to 37.5°C has led to significantly increased values of the color of the stored flour. Besides, increasing the storage period one day more has led to decreasing the values of the color of the stored flour. However, there has been no significant change to the subsequent periods of storage. The overlap between both factors of temperature and storage periods has a significant effect on the flour color. There has been a significant decrease of the enzyme activity (the height values of the falling No.). But there is a noticeable increase to the falling No. values of the stored flour by 37.5°C when increasing the storage periods from one day to ten days and thirty days. This effect, nonetheless, has not reached the significant level.

Research progress on properties of pre-gelatinized starch and its application in wheat flour products

Starch is the most abundant organic compound in nature,second only to cellulose.However,the conserved structure of native starches limits their properties and applications.Therefore,it is often necessary to modify them to obtain specific properties.As a common green and safe physical modification method,pre-gelatinization can improve the cold water solubility and swelling power of starch.The typical preparation methods of pre-gelatinized starch include spray drying,extrusion,and drum drying.Spray-dried pre-gelatinized starch still had good granule shape,but the increase of cold water solubility and cold paste viscosity was relatively small.Extruded and drum-dried pre-gelatinized starch showed serious structure destruction,significant increases in cold water solubility and cold paste viscosity,but relatively low hot paste viscosity.The properties of pre-gelatinized starch obtained by different methods are different,so do their effects on the quality of flour products.Wheat flour products,as one of the leading staple food for the people all over the world,play a vital role in people's daily life.With the improvement of people's living standards,more and more special flour products with unique features have received attentions of consumers and researchers.However,the sensory characteristics of special flour products are often inferior to traditional flour products,which limits its development.The unique functional characteristics of pre-gelatinized starch make it expected to play an essential role in the quality improvement of featured flour products.In this paper,the granule morphology,crystal structure,hydration and gelatinization properties of pre-gelatinized starch prepared by three common methods and their application in flour products were reviewed,which provides a theoretical basis for the application of pre-gelatinized starch in food industry.