Research Project: Developing Accurate and Efficient Laboratory Methods for Testing End-use Qualities of Pulse Crops, Identify Factors Associated with End-use Quality, and Develop Processes to Add Value to Pulses

Location: Small Grain and Food Crops Quality Research

2023 Annual Report

Objectives
Objective 1: Develop novel techniques to evaluate pulse crop properties such as water holding capacity, starch pasting quality, protein extractability, and mixing characteristics with cereals; discover high-throughput assays to measure these characteristics and develop an efficient service lab to provide these services to breeders. (NP306, C1, PS 1A and 1B). Objective 2: Develop novel techniques for incorporating pulse ingredients into bread recipes to assess dough and bread quality parameters such as milling quality, dough strength, baking qualities, and density, and develop a service lab to help breeders incorporate these traits into new pulse varieties. (NP 306, C1, PS 1A and 1B). Objective 3: In collaboration with breeders, determine the impact and variability induced by breeding and processing on the nutritional quality (proximates, micronutrients, selected other nutrients) of pulse foods. (NP 301, C1, PS 1A and 1B; NP 107, C1, PS 1A). Objective 4: Develop knowledge for incorporating pulse ingredients into novel food applications (e.g., beverages, dairy products, meat analogues), identify techniques for measuring properties of pulses to enable development of ‘healthy’-food applications, and provide support for breeders to incorporate these traits into new pulse varieties (NP 306, C1, PS 1A and 1B).

Approach
Facilities and protocols will be established to study the functional properties of whole and fractionated pulse crop ingredients that would be relevant to food industry applications. Research will be conducted to understand how pulse ingredients can be incorporated into bread recipes (at different inclusion percentages) to assess dough and bread quality parameters. These will include milling quality, dough strength (mixograph measurements), baking qualities (loaf height, color, crust strength, size of air pockets, and texture of slices), density, etc. Methods will also be established to conduct compositional analyses on different pulse varieties, breeding materials, and pulse fractions from these germplasm sources. Research will be conducted to develop high-throughput assays for functional and compositional traits. The Category 1 scientist and staff will establish a Pulse Quality Service laboratory with standardized procedures for accepting samples, generating data, and releasing information to breeders and other pulse scientists to help develop pulse lines that might be used as ingredients for bread or other pulse-based products.

Progress Report
This is a new project (as of March 2020) to establish a Pulse Crop Quality Laboratory to develop accurate and efficient laboratory methods for testing end-use qualities of pulses and to work with public pulse breeders to enhance germplasm to add value to pulses. In fiscal year (FY) 23, work was completed to remodel space in our Biosciences Research Laboratory to house the new pulse service and research laboratory. Equipment needs continued to support the new lab continued and position descriptions are in progress to recruit two scientists. Analyses of pulse seed mineral concentrations were carried out during the year, in collaboration with ARS researchers in Pullman, Washington and Mandan, North Dakota, as well as several University cooperators for a lentil project. Seed samples were received for each of the studies, seeds were ground and digested, and mineral concentrations were determined by optical emission spectroscopy. The results were used to assist both genetic studies to improve seed mineral quality and field studies to assess the impact of agronomic practices on seed mineral quality. Research progress in FY23 also involved a Kansas State University cooperator who was funded through a Non-Assistance Cooperative Agreement to examine bread-making performances of whole wheat flour fortified with pulse flours. These studies are being conducted to develop methods that will be established in the Pulse Quality Lab as a standard measurement for pulse breeders. During FY23 the cooperator investigated the flow properties of various particle-sized pulse flours and compared them to wheat flour. Chickpea flour was found to be highly cohesive and non-flowing, with high compressibility, which could pose challenges for transportation and storage. On the other hand, medium and large-sized lentil flours showed better flow properties that are comparable to wheat flour. The work suggested that the high lipid content in chickpea flour may have contributed to its poor flowability. The roller milling methods developed for dry peas, chickpea, and lentils were further applied to different dry beans with appropriate mill setting adjustment, and dehulled dry bean flours were successfully produced. These findings could have implications for the pulse flour industry and the development of innovative processing methods. With respect to breadmaking qualities, the research showed that incorporating chickpea flour at a level of 7.5% (w/w flour basis) or lower clearly improved the mixing stability and dough strength of wheat flour. Adding the insoluble fraction of the chickpea flour resulted in better stability and extended dough strength compared to other fractions, while adding the soluble fraction of chickpea flour weakened the dough. At the optimum incorporation level (7.5%) or lower, the inclusion of chickpea flour did not alter the physical, texture, or taste attributes of the bread. The cooperator also studied the impact of dry bean flour incorporation on the quality of whole wheat flour bread. Sixteen different types of beans with wide genetic variability were milled to obtain pulse meal. The pulse meal was incorporated in commercial whole wheat flour at 7.5% inclusion level and bread was baked utilizing the American Association of Cereal Chemist International (AACCI) standard baking method. The bread loaf volume and specific loaf volume which are the most important bread quality indicators were measured. The specific loaf volume of the different bread ranged from 67% to 99% of the volume of the control commercial whole wheat flour bread. The top five pulse meal incorporated breads, in terms of specific loaf volume, were bambara groundnut bread, mung bean bread, rice bean bread, pigeon pea bread, and cowpea bread. Finally, to optimize the quality and sensory characteristics of breads from pulse-fortified whole wheat flour, experiments demonstrated some beneficial effects of using conventional dough improvers (vital wheat gluten, enzymes, hydrocolloids, emulsifiers) in improving dough processibility and baking of the wheat/pulse composite flours. These studies are ongoing.

Accomplishments

Review Publications
Nkurikiye, E., Tilley, M., Siliveru, K., Li, Y. 2023. Bread-making properties of varying size pulse flours at different ratios of application in composites with refined wheat flour. Journal of Texture Studies. https://doi.org/10.1111/jtxs.12742.
Tavarez, M., Grusak, M.A., Sankaran, R.P. 2022. Effects of zinc fertilization on grain cadmium accumulation, gene expression, and essential mineral partitioning in rice. Agronomy. 12. Article 2182. https://doi.org/10.3390/agronomy12092182.
Narayanan, N., Cueto-Reaño, M.F., Eroglu, S., Ludwig, Y., Okwuonu, I., Taylor, N.J., Grusak, M.A. 2022. Iron biofortification through genetic modification in rice, wheat, and cassava and its potential contribution to nutritional security. CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources. 17. Article 11. https://doi.org/10.1079/cabireviews202217011.