Flour Particle Size Research Articles

Particle Size as an Indicator of Wheat Flour Quality: A Review

Wheat flour is one of the most important food raw materials, with its quality determined by various indicators. One such indicator is particle size and granulometric distribution. In recent years, numerous studies have focused on the effect of flour and bran particle size on the properties of cereal products such as bread, pasta, noodles, and cookies. The aim of this review was to analyze the extent to which this parameter influences the properties of these cereal products. Additionally, the relationships between flour particle size and its chemical composition were presented. Key factors affecting the granulometric composition of flour, related to wheat grain properties and the grinding process, were also discussed. The study specifically focuses on research conducted in the last five years.

Impact of Particle Size on the Physicochemical, Functional, and In Vitro Digestibility Properties of Fava Bean Flour and Bread.

Fava beans, renowned for their nutritional value and sustainable cultivation, are pivotal in various food applications. This study examined the implications of varying the particle size on the functional, physicochemical, and in vitro digestibility properties of fava bean flour. Fava bean was milled into 0.14, 0.50, and 1.0 mm particle sizes using a Ferkar multipurpose knife mill. Physicochemical analyses showed that the 0.14 mm flour had more starch damage, but higher protein and fat contents. Functionality assessments revealed that the finer particle sizes had better foaming properties, swelling power, and gelation behavior than the coarse particle size. Emulsion capacity showed that for all the pH conditions, 1.00 mm particle size flour had a significantly higher (p < 0.05) oil droplet size, while the 0.5 and 0.14 mm flours had smaller and similar oil droplet sizes. Moreover, in vitro digestibility assays resulted in improved starch digestion (p ˂ 0.05) with the increase in flour particle size. Varying the particle size of fava bean flour had less impact on the in vitro digestibility of the bread produced from wheat-fava bean composite flour, with an average of 84%. The findings underscore the critical role of particle size in tailoring fava bean flour for specific culinary purposes and nutritional considerations.

Quality and nutritional attributes of whole einkorn flour and its suitability for fresh noodle production compared to whole wheat flour

AbstractBackground and ObjectivesThis study investigated the physicochemical properties, particle size, pasting properties, phenolic acids, carotenoid content, and fresh noodle quality characteristics of whole einkorn flour (WEF) in comparison with whole wheat flour (WWF). Three WEF samples from different cultivation regions in Turkey were analyzed.FindingsThe WEFs exhibited significant variations in all quality characteristics compared to WWF, influenced by different einkorn growing environments. Phenolic acid and carotenoid contents, along with antioxidant activity, were highest in WEF1 and WEF2, highlighting their potential nutritional benefits. Noodles made from WEF3 demonstrated quality equivalent to that of WWF, although their protein content and nutritional value were relatively lower than those of WEF1 and WEF2.ConclusionsThis research demonstrates the potential of WEF for fresh noodle production with quality comparable to WWF. The nutritional value varies by cultivation area, emphasizing the importance of selecting appropriate cultivars and growing conditions for optimal results.Significance and NoveltyThis study highlights, for the first time, the nutritional value and quality characteristics of WEF influenced by growing areas, impacting its suitability, equivalent to WWF, for producing fresh noodles.

Effect of wheat flour particle size on the quality deterioration of quick-frozen dumpling wrappers during freeze-thawed cycles

To reveal the effect of wheat flour particle size on the quality deterioration of quick-frozen dumpling wrappers (QFDW) during freeze-thawed (F/T) cycles, the components and physicochemical properties of wheat flours with five different particle sizes were determined and compared, along with the changes in texture and sensory properties, water status, and microstructure of QFDW during F/T cycles. Results showed that as particle size decreased, the damaged starch content and B-type starch content increased, the water absorption increased, and the gluten strength decreased. Furthermore, F/T cycles negatively impacted the quality of QFDW, evidenced by decreased texture properties and sensory evaluation score, water redistribution, higher freezable water content, and disruption of gluten network. Notably, QFDW made from larger particle size wheat flours required the shortest duration when traversing the maximum ice crystal formation zone. The QFDW made from larger particle size wheat flours formed a more stable starch-gluten matrix, which resisted the damage caused by ice recrystallization, demonstrating better water binding capacity and F/T resistance. The results may provide theoretical guidance for the study of QFDW quality and the moderate processing of wheat flour in actual production.

Increasing particle size of oat flours decreases postprandial glycemia and increases appetite in healthy adults

Consumption of oats is associated with lowered risks of type 2 diabetes and obesity. However, many oat-based products (e.g., breakfast cereals) use finely milled flours but are associated with health claims based on oats of larger particle sizes. The objective of this study was to test the hypothesis that increasing oat flour particle size will result in lower postprandial glycemia and appetite. Using a randomized-controlled, crossover design, 20 participants (10 males, 10 females; age: 25.3 ± 1.0 years; body mass index: 23.2 ± 0.6 kg/m2) consumed a serving of porridge made using 40 g of coarse (675.7 ± 19.6 µm), whole (443.3 ± 36.2 µm), fine (96.0 ± 2.1 µm), or a commercial (375.9 ± 14.8 µm) oat flour unmatched in available carbohydrate, protein, and dietary fiber content. After a 12-hour overnight fast, blood glucose, insulin, and appetite were measured at 15 to 30-minute intervals over 120 minutes posttreatment consumption. Coarse and whole flours led to lower blood glucose between 30 and 60 minutes (P < .02). Blood glucose area under the curve (AUC) was lower after coarse than fine and commercial oat flours (P < 0.03), and after whole than fine oat flour (P < .002). Both coarse and whole oat flours resulted in lower insulin AUC than finer flours (P < .05). Appetite AUC was lower after the commercial than coarse flour (P < .007). Controlling milling to produce coarser oat flour to add to common foods may have health benefits. This study was registered at ClinicalTrials.gov (NCT05291351).

Удельные энергетические затраты на измельчение древесины при подготовке композита для 3D-печати

The Northwestern Federal District is a region of Russia rich in a variety of wood species. The properties of wood in this region differ significantly from the properties of wood grown in other countries or in the eastern part of Russia, which leads to differences in energy costs of grinding wood. The aim of this research has been to estimate the specific energy costs of grinding wood to the state of wood flour, which will be used as the basis for wood polymer composite consumables in additive technologies. Wood flour has been obtained by grinding wood in a laboratory disk mill, repeatedly reducing the particle size. The granulometric composition has been analyzed for beech, oak, larch, alder and pine wood at 1, 3, 5 and 10 grinding cycles. Particle sizes have been determined by analyzing images obtained using an optical microscope and processed in the ImageJ graphic program. The specific energy costs of grinding have been estimated by recording the power with a wattmeter every second with repeated feeding of wood flour for the known mill productivity. When calculating the specific energy consumption, the moisture content of each wood species has been taken into account, as well as productivity losses associated with the adhesion of wood particles to the working surfaces of the dispersing set and the inner area of the disk mill body. The research has revealed a relationship between the specific energy costs and the particle size of wood flour obtained from various wood species. Regression analysis of curves corresponding to different wood species has made it possible to obtain exponential and power-law dependencies that do not contradict the fundamental theoretical laws of grinding solid particles. Based on these results, pine wood flour has been recognized as the most energy-efficient option. The established dependencies can be used to predict the specific energy consumption for grinding beech, oak, larch, alder and pine wood in disk mills.

Radio frequency drying on functional diversity of tiger nut flour: Effects on physicochemical, structural, and rheological properties

Tiger nut (TN) is a valuable nutrient and gluten-free tuber. To achieve high-quality TN flour as functional ingredients in food, it is essential to develop effective drying technologies for TN. Five drying methods including natural drying (Control), hot-air drying (HD), radio frequency single drying (RFSD), RF assisted hot-air drying (RFHD), and RF- vacuum drying (RFVD) were selected and compared to determine their effects on physiochemical, structural, and rheological properties of TN flour. Results showed that RF drying (RFD) significantly improved the hydration, oil-absorbing, and antioxidant activity capacity, especially for RFVD. RFHD exhibited greater color (BI = 13.80 ± 0.05 and C = 10.26 ± 0.05) and reducing sugar content (253.50 ± 2.27 mg d.b.) than RFSD and RFVD. The gelatinization temperature, enthalpy value, and particle size (57.30–269.33 μm) of TN flour were reduced. The structural property results indicated that RFD reduced the relative crystallinity and short-range ordering of the flour, altered protein secondary structure, and caused the damaged microstructure in comparison with Control and HD groups. All sample gels exhibited a weak strain overshoot behavior (type III) under large amplitude oscillations, and RFD resulted in a reduced viscoelastic behavior. RFD could be an effective method to produce functional TN flour.

Sourdough Bread Quality: Facts and Factors.

The term "sourdough" denotes a dough composed of flour and water, fermented through the action of yeast and lactic acid bacteria. The utilization of sourdough fermentation technology can enhance the nutritional attributes of bread made from wheat grain. In recent times, sourdough bread has experienced a resurgence, fueled by growing consumer demand for healthier bread options. The market dynamics for sourdough illustrate its rapid expansion and significant role in the contemporary food industry. Sourdough fermentation improves nutritional qualities by altering the structure and function of proteins and starch, enhancing dietary fiber, volatile compound profiles, and antioxidant activity, and reducing FODMAPs. The quality of sourdough bread is influenced by several factors, including fermentation environment, flour particle size, protein quality, starch characteristics, and dietary fiber composition. Moreover, the incorporation of alternative grains (intermediate wheatgrass and legume flour) and non-flour ingredients (fruits, herbs, and dairy products) presents opportunities for creating sourdough bread with unique sensory and nutritional profiles. This review offers updated insights on the quality aspects of sourdough fermentation, the factors that influence the effectiveness of the sourdough fermentation process, sourdough technology with unconventional and non-flour ingredients, and the potential market for frozen sourdough, considering its convenience and extended shelf life.

Effect of blade rotational speeds on the performance of cassava milling machine

Abstract Cassava (Manihot esculenta) is a food source of carbohydrates in Indonesia. Cassava flour is used as raw material for processed food products. A performance evaluation of the cassava milling machine has been carried out by varying the blade rotational speeds. There are three parameters related to machine performance and two parameters related to cassava flour. The machine performance parameters are capacity, electric power, and specific energy, while the cassava flour parameters are temperature and particle size distribution. The performance evaluation showed that the higher the blade rotational speeds, the higher the capacity and electrical power, at 8000 rpm the resulting capacity and electrical power are 465.5 kg/hour and 2418.8 W respectively. At the same blade rotational speeds, the lowest specific energy is also obtained, at 19,540.52 J/kg. In all variations of blade rotational speeds, there is an increase in temperature from cassava chips to cassava flour, an average of 2.7 °C. Meanwhile, the cassava flour particle size showed that in each variation of the blade rotational speed, the dominant flour size is 60-80 mesh. At a blade rotational speed of 8000 rpm, the cassava flour particle size of 60-80 mesh is the largest when compared to other blade rotational speeds at 45% of the cassava flour produced by flouring. Based on statistical analysis, by varying the blade rotational speeds, it is stated that there are no significant differences in the results of the performance parameters except for the flouring capacity parameter at blade rotational speeds of 8000 rpm.

Particle size reduction influences starch and protein functionality, and nutritional quality of stone milled whole wheat flour from hard red spring wheat

Flour particle size (PS) distribution plays a crucial role in determining the functional properties of starch, protein, and influences the nutritional properties, which ultimately is reflected in the end-product quality. For stone-milled whole wheat flour (WWF) bakers often prefer finer PS for improved color and texture, despite this can sometimes negatively affect other quality aspects. Therefore, understanding the contribution of PS reduction on the functional properties of stone-milled WWF is crucial. This study investigated Hard Red Spring (HRS) WWF of which the mean PS was reduced from 151 μm to 117 μm, the possible finest PS by a “Kombi mill type A 500 MSM” stone mill. PS reduction increased starch damage from 6.58% to 6.71%. Also, the amylose content reduced from 31.7% to 29.4%. However, an increase in syneresis, solubility, oil-holding capacity, and peak viscosity was observed. Glutopeak and wet gluten showed an increased gluten strength. Glutenin/gliadin, polymeric/monomeric protein ratios, and percentage of unextractable polymeric protein were increased by 2.10%, 4.11%, and 4.55%, respectively, indicating increased availability of proteins with relatively larger molecular sizes by PS reduction. The relative proportion of glutenin and gliadin subgroups were also changed. Dietary fiber and resistant starch contents were found to be lower. However, the reduction in phytic acid and FODMAPs is considered beneficial. PS reduction ultimately improved bread loaf volume and crumb structure. Overall, PS reduction of WWF by stone-milling brought positive changes to several functional properties of protein and starch and positively improved the dough rheology and end-product quality.

Microstructural, physicochemical, thermal, and rheological properties of buckwheat flour treated with high-pressure at selected moisture contents

This study investigated the role of water in the high-pressure treatment (300–600 MPa/15 min) of buckwheat (Fagopyrum esculentum) flour and property changes in post-process samples. DSC and XRD measurements demonstrated complete gelatinization of buckwheat starch occurred at 600 MPa. The particle size of flour decreased above 450 MPa. HP-treatment successfully transformed the crystalline A-type structure of hydrated samples into a B-type structure. Dry samples did not gelatinize or exhibit any structural change, even at 600 MPa. The progress of gelatinization and gel rigidity of post-process samples were measured on a rheometer. The thermal transition captured in rheometer and DSC differs significantly. The impact of further heating on the pressurized samples resulted in a significant improvement in their mechanical rigidity. Overall, this study confirmed that an optimum flour-to-water ratio should be maintained during HP treatment to achieve the desired changes in buckwheat flour so that it could be used in food formulation.

Study on the Effect of Sorghum Flour Particle Size on the Storage Quality of Leavened Pancakes.

Pancakes prepared with sorghum flour possess a high nutritional value, yet their quality is unstable and prone to degradation during storage. This instability can be attributed to the particle size of coarse cereal powder, which significantly influences the quality of flour products during storage. In this study, changes in the quality of these pancakes, prepared with varying particle sizes of sorghum flour, were meticulously analyzed during cold storage using advanced instruments such as a texture analyzer, nuclear magnetic resonance spectrometer, differential scanning calorimeter, X-ray diffractometer, and Fourier transform infrared spectrometer. Findings revealed that the hardness of leavened pancakes significantly increased over time. After a refrigeration period of 7 days, the hardness of wheat flour leavened pancakes increased by 56.60%. However, with a decrease in the particle size of sorghum flour, the increase in hardness diminished, thereby delaying the aging process of the pancakes. As the storage duration was extended, moisture migration within the pancakes occurred, and the sorghum flour pancakes with a smaller particle size exhibited a reduced moisture change rate, indicating an enhanced water holding capacity. In comparison to their wheat flour counterparts, sorghum flour leavened pancakes exhibited a substantial reduction in retrogradation enthalpy and crystallinity. The inclusion of sorghum flour effectively inhibited amylopectin recrystallization, thus slowing down the aging process of the pancakes. This inhibitory effect was more evident with decreasing sorghum flour particle sizes. Fourier transform infrared data indicated no significant alterations in absorption peaks across various wavelengths during cold storage. Although starch short-range orderliness increased with storage time, the use of sorghum flour with smaller particles reduced the degree of short-range orderliness in starch molecules throughout the cold storage period. Sorghum flour with a smaller particle size can inhibit water migration and amylopectin recrystallization, which subsequently delays pancake aging and enhances its quality stability during storage.

Comprehension of drying kinetics and stone milling process of chestnuts: a focus on moisture content, milling speed, and energy evaluation.

Chestnut flour plays an important role in the production of bread, bakery products, and gluten-free foods. Most of the references in the literature focus on the drying process itself and not on the effects of the drying and milling processes. Moreover, the literature is lacking recommendations regarding optimal moisture content and milling speed, thus motivating the present study. The first aim is to understand the chestnut drying process through an in-depth evaluation of drying kinetics; the second aim is to assess the effects of three different moisture content (2%, 4% and 6%) and three different stone rotational speeds (120, 220 and 320 rpm) on operative milling parameters (flour yield, milling time, energy consumption, temperature increase, average power, specific milling energy), flour particle size distribution, and chestnut flours characteristics. The results show that moisture content and stone rotational speed have statistically-significant effects on milling operative parameters, flour particle size and chestnut flour composition. In particular, stone rotational speed affected almost all the tested variables (mill operative parameters, flour particle size distribution, and flour characteristics). Therefore, as the stone rotational speed increases, energy consumption, average power, specific energy, and damaged starch content significantly increase. These findings clearly show that moisture content and stone rotational speed are powerful tools that allow the exploiation of the milling process to modulate the characteristics of the obtained flours. In conclusion, two different approaches for chestnut milling were suggested depending on the type of flour to be produced. © 2024 Society of Chemical Industry.

The Hyperglycemic Effect of Different Particle Sizes of Composite Flour from Maize, Wheat and African Breadfruit on Adult Diabetic Albino Rats

The Hyperglycemic Effect of Different Particle Sizes of Composite Flour from Maize, Wheat and African Breadfruit on Adult Diabetic Albino Rats

Estimation of the earlywood and latewood ratio with different particle size of dry and wet milled Japanese cedar wood flour by using hyperspectral imaging

Mechanical properties of wood–plastic composites are influenced by a particle size and surface morphology of wood flour. Generally various sizes of wood flour are produced from single solid wood even if the single process is used. If the different particle size of wood flour is produced from different wood tissue such as earlywood (EW) and latewood (LW), not only particle size but also density and chemical composition of wood flour might influence the mechanical property of final products. This study aims to investigate the relationship between particle size and their origin; EW and LW. EW and LW were separately milled to produce the EW and LW flour by dry and wet milling. Hyperspectral images ranging 400–1000 nm for each wood flour were used as training data. Discriminant model of EW and LW flour developed by PLS-DA showed over 0.77 of accuracy. Then the EW and LW were dry and wet milled together and screened by three different sieve openings to obtain different particle size wood flour. Discriminant model was applied for the hyperspectral images of each size of wood flour to estimate the EW and LW ratio. The result showed that increasing sieve opening resulted in the increasing ratio of LW for dry milled wood flours. The results suggest that the EW was easily pulverized than LW.

Transformation of quinoa seeds to nanoscale flour by ball milling: Influence of ball diameter and milling time on the particle sizing, microstructure, and rheology

Among various size reduction techniques, high-energy ball milling is one of the most attractive means for plant-based foods. The objectives of the work were to investigate the influence of ball diameters (3, 6, and 13 mm) and milling time (2, 4, and 6 h) on particle size and microstructural properties of quinoa flours. Particle size analysis demonstrated that ball-milled particles were mostly in the range of nanoscales (122–295 nm). A longer milling time with larger balls significantly increased the particles to microscale (3.58 μm). The scanning electron microscopy displayed the conversion of quinoa starch granules into flakes after ball milling, however, the X-ray diffraction crystallinity peak observed at a 2θ value of 19–20° did not change. The AFM roughness parameters, arithmetic and squared mean heights of flours increased with increasing ball diameters. These results provided new insights for the application of ball milling, in particular in functional foods and pickering emulsion.

Gluten-free lentil cakes with optimal technological and nutritional characteristics.

The celiac population usually struggle finding nutritive gluten-free (GF) baked goods. GF foods can be improved using legume flours. Eleven GF cake formulations were elaborated according to different percentages of lentil flour (LF), corn flour (CF) and rice flour (RF) using a simplex lattice design. Water holding capacity and particle size of flours were evaluated. Moisture, aw, pH, specific volume, texture profile, relaxation, color and alveolar characteristics were determined for crumbs of all formulations. An optimization process was used to enhance the technological and nutritional attributes, selecting the three best formulations containing LF: 46% LF + 54% RF (CLF+RF); 49% LF + 51% CF (CLF+CF); and 100% LF (CLF), evaluated in their proximal composition and sensory characteristics. Linear and quadratic models for predicting the behavior of GF lentil cakes were obtained. LF and CF could favor water incorporation and show more resistance to enzymatic digestion than RF. Formulations with LF showed an improvement in specific volume and alveolar parameters, while use of RF led to better cohesiveness, elasticity and resilience but with a deterioration in chewiness and firmness. CLF can be labeled as high in protein and fiber and presented the lowest amounts of lipids, carbohydrates and energy content. Consumer preference leaned towards CLF+RF. It was possible to elaborate GF cakes using LF, obtaining nutritive products that can be offered to people intolerant to gluten ingestion. © 2024 Society of Chemical Industry.

Large flour aggregates containing ordered B + V starch crystals significantly improved the digestion resistance of starch in pretreated multigrain flour

The starch digestibility of flour is influenced by both physicochemical treatment and flour particle size, but the interactive effect of these two factors is still unclear. In this study, the effect of pullulanase debranching, combined with heat-moisture treatment (P-HMT), on starch digestibility of multi-grain flours (including oat, buckwheat and wheat) differing in particle size was investigated. The results showed that the larger-size flour always resulted in a higher resistant starch (RS) content either in natural or treated multi-grain flour (NMF or PHF). P-HMT doubled the RS content in NMFs and the large-size PHF yielded the highest RS content (78.43 %). In NMFs, the cell wall integrity and flour particle size were positively related to starch anti-digestibility. P-HMT caused the destruction of cell walls and starch granules, as well as the formation of rigid flour aggregates with B + V starch crystallite. The largest flour aggregates with the most ordered B + V starch were found in large-size PHF, which contributed to its highest RS yield, while the medium- and small-size PHFs with smaller aggregates were sensitive to P-HMT, resulting in the lower ordered starch but stronger interactions between starch and free lipid or monomeric proteins, eventually leading to their lower RS but higher SDS yield.

Investigating potato flour processing methods and ratios for noodle production.

A partial substitution of wheat flour with potato flour processed by various procedures was used to determine an optimal potato pretreatment method for noodle processing. Wheat flour was substituted with 10%, 30%, and 50% potato flour. Potato flour (PF) was processed using two different methods, including freeze-drying (FD) and low-temperature blanching, then oven drying (LTB_OD). The results showed that substituting wheat flour with freeze-dried (FD) flour (44.29 μm) significantly decreased the mean particle size of the blended flour, while LTB_OD flour (223.09 μm) increased the mean particle size. The pasting properties of wheat flour significantly improved when potato flour was added, with FD flour blends having the highest results. The highest dough development time (14.46 min) was attained when LTB_OD potato flour was substituted up to 50%. The microstructure images showed a poor and discontinuous gluten framework when potato flour content reached 50%. Adding potato flour decreased noodles' brightness (L*) while increasing their yellowness (b*). Noodles made from wheat and LTB_OD flour blends resulted in the highest cooking loss. The texture properties of noodles deteriorated when potato flour content reached 30%. Substituting up to 30% with freeze-dried flour and 10% LTB_OD resulted in noodles with the highest overall liking scores. The study suggests that for optimal noodle processing, substituting wheat flour with FD potato flour is more favorable than using LTB_OD, as it improves particle size, pasting properties, and overall liking scores while minimizing adverse effects on texture and cooking loss.

Effect of High-Protein and High-Fiber Breaders on Oil Absorption and Quality Attributes in Chicken Nuggets.

Consumption of fried foods is associated with a higher risk of cardiovascular and other diseases; therefore, consumers are looking to reduce fat intake. We evaluated the effect of high-protein breaders and fiber on oil absorption and quality attributes in chicken nuggets, using flour blends (wheat, chickpea, coconut, oil-quinoa-chia), soy protein concentrate, and brewers' spent grain. We evaluated the chemical composition, water and oil retention capacity (ORC), viscosity profile, and flour particle size distribution, along with the developed breaders (Formulation 1 and 2) and a commercial breader (CB), in addition to texture, color, fat, and moisture contents of the fried chicken nuggets prepared with the developed breaders and the CB. The total dietary fiber content (TDF) of the nuggets breaded with only Formulation-1 and CB was determined. Nuggets breaded with Formulation-1 showed lower (p ≤ 0.05) ORC, better moisture retention (67.6%), and more TDF (4.5% vs. 2.3%, p ≤ 0.05) compared to CB-breaded nuggets. Nuggets with Formulation-1 showed the expected texture and color characteristics for fried products. Formulation-1 has the potential to be used as a breader due to its moisture, reduced ORC, and the texture and color it imparts to the fried nuggets, providing higher amounts of nutrients and possible health benefits.