Pea flour is increasingly used in food preparations due to its health benefits. Milling is an important requirement in preparing pea flour for use in recipes. This study investigated the impact of particle sizes on flour quality and functionality. Yellow pea seeds were cyclone milled to maximum particle sizes of 0.25, 0.50 and 1.00 mm. Microstructure, rheological and thermal characteristics of the samples were examined using SEM, rheometer and DSC, respectively. Chemical profiles of the samples were monitored using FTIR. Techno functional properties of the samples were assessed. Principal component analysis (PCA) was applied to corelate the different sample attributes to particle sizes. Results showed that particle sizes have significant impact on pea flour quality. SEM and FTIR analysis showed that flour samples milled to maximum particle size of 0.25 mm had higher disentangled protein particles, more damaged starch and changes to flour chemical composition. Flour milled to 0.50 mm maximum particle size showed highest values for storage modulus (G′), loss modulus (G″), viscosity, higher peak temperature and least onset gelatinization temperature. Techno-functional properties such as water absorption, oil absorption, foaming capacity and stability differed significantly and were higher for samples with 0.50 mm maximum particle size. PCA plots elucidated milling impact to flour functionality and grouping. These findings demonstrate that milling conditions can be a potential tool to manipulate flour quality and suitability to different application, further leading towards standardizing and prediction of pea flour functionality.

The roller mill is a highly flexible milling equipment used by millers and food processors to create flour fractions that could be used as-is or blended to meet specific end-use requirements. During the milling process, the molecular and microstructure of the flour are impacted by the mill settings. Because the structure-function relationship is crucial to creating high-quality end products, a thorough understanding of such functional properties is important. Therefore, in this study, the functional properties of roller-milled chickpea and navy bean flours, viz. starch lamellar structure, starch crystallinity, and porosity, were studied. The conventional techniques of X-ray microtomography (XCT), small-angle X-ray scattering (SAXS), and powder X-ray diffraction (PXRD) that are commonly used to study these parameters suffer from limitations in terms of resolution, wavelength selection, and coherence, and are laborious. In this pioneering study, synchrotron X-rays were used due to their ultra-high resolution, robustness, and reliability to investigate the molecular changes resulting from different mill settings. The flours were categorized into different break and reduction stream flours and evaluated for porosity, starch lamellar structure, and crystallinity using XCT, SAXS, and PXRD, respectively. The preliminary analysis revealed that break stream flours had higher crystallinity and porosity than reduction stream flours with distinct lamellar structures. In conclusion, the use of synchrotron X-rays in this study proved to be a powerful tool in investigating the molecular changes in roller-milled pulse flours. This research has significant implications for food processors in creating healthier and more nutritious products for consumers.

Though regarded as a sustainable alternative to protein production to augment increasing demand, the sustainability outlook of pea-protein extraction is dented by the gross underutilization of its co-product, pea starch. This gap has heightened interest in designing innovative and sustainable upcycling actions to attain optimal sustainability benefits. Pea starch contains about 80-90 % starch and minute compositions of fibre, proteins, and ash, indicating its viability as a carbon-rich candidate for biotechnological use. In this study, we leveraged the unique characteristics of pea starch in the designing a production system for single-cell protein, taking the prospects it holds in sustainably augmenting protein supply and promoting a circular bioeconomy. Solid-state fermentation, increasingly prominent for its technoeconomic and environmental benefits due to less demand for energy and water, was preferred as the biotechnological alternative for the process design. To ascertain the sustainability performance of the designed system, life cycle and technoeconomic assessments were conducted using appropriate simulation software. Furthermore, hotspot and sensitivity analyses were performed to identify operational flashpoints and test the system’s response to resource and technological variations. We hope to provide baseline insights to justify the production and sustainability potentials of single cell protein production from pea starch. In the long run, this will serve as a valuable guide for developing and commercializing a pea-starch-based single-cell protein production system.

Red beet antioxidant compounds and pea protein flour fractions can combine to create novel protein-based ingredients. Red beet extract is rich in antioxidants, such as betalains and phenolic compounds, that have commercial value for improving the color characteristic of food products. Our study investigated the interactions of red beet pomace extract with pea protein flour (PF), and stage 1 and stage 2 foamate obtained from foam fractionation of pea protein flour (PPFF 1 and PPFF 2), respectively. The effect of such interactions on pea protein function and conformation was also studied. Circular Dichroism (CD) and Fourier transform infrared spectroscopy (FTIR) were used to analyze conformational changes in the protein structure with different concentrations of red beet extract (1-5g/mL). The addition of red beet extract affected the α-helix and β-sheet structures in PF, PPFF1 and PPFF2, and the antioxidant compounds in red beet were more likely to form non-covalent interactions with pea protein fractions. PPFF2 showed improved foaming, emulsifying and solubility properties after complexation with red beet extract. Furthermore, the complexation of PPFF2 and red beet extract showed improved ability of pea proteins to act as an antioxidant. The findings of this research are important for a better understanding of the underlying mechanisms and potential applications of red beet extract and pea protein complexes as functional ingredients in food products.