Milling and differential sieving to diversify flour functionality: A comparison between pulses and cereals

Development of novel process for production of high-protein soybean semolina and its functionality

This study aims to develop a semolina roller milling process for differently processed soybeans and investigate the physicochemical, functional, and pasting properties of the resulting milled products. Soybeans underwent pre-milling treatments: roasting (RT), germination (GT), and hydrothermal processing (HT) before being roller-milled to produce fine semolina (FS), coarse semolina (CS), husk (H), and flour (F) fractions. The results indicated that FS yield was highest for GT (47.21%) and lowest for HT (42.52%), while CS yield was highest for control (31.83%) and lowest for GT (26.79%). Nutrients were unevenly distributed among the milled products, with ash, protein, and total dietary fiber concentrated in the CS across all treatments. Both water and oil holding capacities were highest for HT and lowest for GT. Pasting properties, including peak viscosity, hot paste viscosity, and cold paste viscosity, were highest for control and lowest for HT and RT soybean. These findings demonstrate that soybeans can produce uniformly sized semolina under standardized roller milling parameters. This emerging process will provide a new possibility for utilizing protein-rich soybeans. Utilizing soybean semolina as an ingredient could enhance the use of protein-rich soybeans in daily diets and open new opportunities for the soy-processing industry.

Glycemic impact of cereal and legume-based bakery products: Implications for chronic disease management

This review examines the glycemic impact of cereal and legume-based bakery products and their potential role in chronic disease management, particularly in type II diabetes and cardiovascular diseases. The primary objective is to assess the glycemic index (GI) and glycemic load (GL) of bakery products made from cereals such as wheat and barley, and legumes like chickpeas, and to explore their effects on postprandial blood glucose response. Cereal-based products typically exhibit higher GIs (55-80), while legume-based bakery products demonstrate lower GIs (40-50), potentially contributing to better glycemic control. Incorporating legumes into bakery formulations can lower their glycemic index by up to 25 %. Legume-enriched bakery products may effectively manage blood glucose and reduce chronic disease risks like diabetes. However, more long-term studies are needed to confirm their broader benefits. This review emphasizes the need for innovation to improve the nutritional and sensory appeal of functional foods.

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).

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.

Important roles of coarse particles in pasting and gelling performance of different pulse flours under high-temperature heating

Dehulled pea, lentil, and faba bean grains were milled into flours with 0.5- to 2.5-mm sieves. As the particle size decreased, damaged-starch contents of the flours from the same pulse crop increased. At a holding temperature of 95 °C in RVA, peak and final viscosities and gelling ability of the flours generally increased as the particle size decreased. When the holding temperature increased from 95 to 140 °C, pasting viscosities of pea and lentil flours and gel hardness of lentil flours gradually decreased. In contrast, pasting viscosities and gel hardness of faba bean flours reached the highest values at 120 °C. The comparison of the pulse flours varying in particle size across the three market classes revealed that coarse particles comprising agglomerated starch, protein, and dietary fiber (i.e., particles of the second peak in the bimodal particle-size distribution curves) showed significant correlations with certain important functional properties of pulse flours.

High-Pressure Pasteurization of Oat Okara

The issue of the short microbiological shelf life of residues from the plant-based beverage industry creates a large food waste problem. Today, the oat beverage residue, in this study referred to as oat okara, is generally converted to energy or used as animal feed. High-pressure pasteurization (200 MPa, 400 MPa, and 600 MPa) was applied to oat okara to investigate the effect on shelf life and microbiological activity. A 4-week microbiological storage study was performed and thermal properties, viscosity, and water and oil holding capacities were analyzed. The total aerobic count, including yeast and mold, was significantly reduced (p < 0.05) by 600 MPa after four weeks of storage at 4 °C. The content of lactic acid bacteria after four weeks of storage was low for untreated oat okara (3.2 log CFU/g) but, for 600 MPa, the content remained at the detection limit (2.3 log CFU/g). Conversely, the treatments of 200 MPa and 400 MPa increased the microbial content of the total aerobic count significantly (p < 0.05) after two weeks in comparison to untreated oat okara. The thermal properties of untreated and high-pressure-treated oat okara demonstrated an increase in protein denaturation of the 12S globulin, avenalin, when higher pressure was applied (400-600 MPa). This was also confirmed in the viscosity measurements where a viscosity peak for avenalin was only present for untreated and 200 MPa treated oat okara. The water holding capacity did not change as a function of high-pressure treatment (3.5-3.8 mL/g) except for the treatment at 200 MPa, which was reduced (2.7 mL/g). The oil holding capacity was constant (1.2-1.3 mL/g) after all treatments. High-pressure pasteurization of 600 MPa reduced the microbial content in oat okara resulting in a shelf life of 2-4 weeks. However, more research is required to identify the microorganisms in oat okara to achieve a microbiologically safe product that can be used for food applications.