Location: Functional Foods Research
2025 Annual Report
Objectives
Objective 1: Innovate processes to improve the properties of underutilized crops such as sorghum, millet, and hemp seed (SMHS), and their byproducts to enable increased commercial use.
•Sub-objective 1A: Enhance the health-promoting and commercially important functional properties of SMHS flours, fractions or extracts such as proteins, and byproducts by thermomechanical processing treatments alone or in combination to obtain new components and composites.
•Sub-objective 1B: Enhance the health-promoting and commercially important functional properties of SMHS flours, fractions or extracts such as proteins, and byproducts by chemical/enzymatic treatments alone or in combination with either thermomechanical processing.
•Sub-objective 1C: Enhance the health-promoting and commercially important functional properties of SMHS flours, fractions or extracts such as proteins, and byproducts by addition of other grain- or legume-based ingredients for functional composite formation, nutritionally complete diets, and flavor, texture, or structure improvement of food matrices.
Objective 2: Integrate the digestive health attributes of various SMHS components and their composites following innovative applications to improve process economics of food products and develop bioproduct ingredients using SMHS components.
•Sub-objective 2A: Develop food applications from SMHS components and conduct digestive health study.
•Sub-objective 2B: Develop non-food applications from SMHS components.
Approach
The dietary benefits of sorghum, millet, and hemp seed (SMHS) are well established and are increasingly recognized as valuable sources of protein, starch, fiber, antioxidants, and other nutrients. These crops are also drought resistant. They are, however, underutilized and used mainly for animal feed and biofuel production (sorghum) in the Unites States. The overall goal of this project plan is to convert these underutilized crops and their byproducts from milling and biofuel production into value-added food products and bio-products based upon their nutritional, physiochemical or chemical properties. There exist two primary challenges facing wider utilization of SMHS: 1) consumption barrier that stems from characteristics of SMHS and perception; 2) byproducts of biofuel (sorghum) and milling of SMHS could be better utilized to defray production cost. We will focus on identifying the effects of synergistic thermomechanical and biological treatments on SMHS grains, flours, and fractions and developing processing strategy based upon understanding of SMHS component interactions and information of in vitro and in vivo digestive health studies to enhance the nutritional, structural and functional properties of SMHS based food products. The processed SMHS materials will be incorporated into standard food formulations with the aim of maximizing the content of SMHS-based ingredients with marketable sensory properties. Non-food applications will also be investigated based on physical and chemical properties of the end products. The outcomes of this research will expand domestic and international markets for SMHS crops and therefore contribute to the sustainability of US agriculture in the era of climate change.
Progress Report
In May 2020 (and terminated in April 2025), the project plan was started with the overall goal to convert sorghum, millet, and hemp seed (SMHS), and their byproducts from milling and biofuel production into value-added food products and bio-products based upon their nutritional, physiochemical or chemical properties. U.S. farmers of sorghum, millet, and hemp seeds have endured many years of low commodity prices for their crops due to lack of domestic demands, particularly non-feed and non-biofuel demands. The project attempted to address this challenge by broadening the use of SMSH in food products and other high-value products using innovative technologies to process these grains into different fractions and extracts. The approach started with milling, jet cooking or enzymatic treatment of SMHS into modified fractions or extracts. The processed SMHS materials were then incorporated into standard food formulations with the aim of maximizing the content of SMHS-based ingredients with attractive sensory properties. Non-food applications were also investigated based on physical and chemical properties of the end products. The outcome of this research will expand domestic and international markets for SMHS crops therefore contributing to agronomic development of rural America.
This project consists of two objectives: Objective 1. Innovate processes to improve the properties of underutilized crops such as sorghum, millet, and hemp seed (SMHS), and their byproducts to enable increased commercial use and Objective 2. Integrate the digestive health attributes of various SMHS components and their composites following innovative applications to improve the process economics of food products and develop bioproduct ingredients using SMHS components.
Under Objective 1: Sorghum, millet, and hemp seed (SMHS) flours were created from commercial whole seeds and milled in the ARS facility in Peoria, Illinois, then further processed into different components. In many instances, physical treatments such as steam jet cooking, roasting, or extrusion, and biological treatments such as fermentation and germination were applied to induce structural or compositional changes in the flours of SMHS. Products were then examined for physical, chemical, and sensory properties of significant importance to the food industry for consumer acceptance. Roasted millets, especially proso millet, and millet flour with better swelling and thickening properties can be used for the development of various functional and healthy food products. We have evaluated the effect of whole grain roasting temperature and time on the nutritional value, digestibility and functional properties (performance in food processing, such as solubility and foaming ability) of whole and ground millets and other grains in the project. The data analysis indicates the property changes from processing SMHS grains enables SMHS components to be used in existing formulations of a wide range of baked goods including cookies, noodle, cakes, and gluten-free breads. One of these property changes was the reduction in particle size of SMHS flour. ARS scientists in Peoria, Illinois discovered that reduction in the particle size of sorghum flour improved functional properties and resulted in desired characteristics of cookies baked by partially substituting wheat flour with sorghum flour. Particle size affected the water uptake and thickening properties of sorghum flour. Cookies can be made with 30% fine particle size sorghum flour that have a more healthful nutritional profile. This study will provide the food industry with the opportunity to add nutritionally interesting and healthy sources of food ingredients to their existing food product lines and benefit sorghum/millet farmers and processors economically.
Dietary fiber, phenolics and antioxidants, were extracted and evaluated for selected SMHS grains. The results provided useful information on the development of nutritional implications of functional foods. ARS researchers in Peoria, Illinois used novel processing technology, such as Steam Explosion (SE) to break up grain structures to improve functional properties of grain flour and release more phenolic compounds that act as antioxidants. Studies revealed a profound effect of temperature on the stability, color, solubility, and nutritional value of SMHS grains. Steam explosion treatment could provide potential health benefit to SMHS food products such as increased antioxidant ability and dietary fiber content. ARS researchers in Peoria, Illinois also explored the potential of milling byproducts of SMHS for other industrial applications. Initial work was focused on identifying components of the grains that exhibit useful properties for industrial applications such as emulsifiers and adhesives.
Hemp is an annual herbaceous plant that belongs to the Cannabinaceae family which includes marijuana. Initially proposed uses for these hemp crops include animal feed, paper production, cannabidiol (CBD), a type of cannabinoids, and even fiber. After the collapse of CBD market, farmers are looking to diversify hemp’s uses beyond the cannabinoids. Hemp seeds can be used as food and extracted for proteins and oils that can be used in many food formulations. Federal regulations require that any hemp-based products or ingredients cannot exceed 0.3% total THC (the compounds that make people high) limit in their products. Current methods being developed for measuring cannabinoids are time-consuming, requiring expensive equipment, reagents, and expertise. ARS researchers in Peoria, Illinois, developed an analytical instrument-based method that rapidly and accurately measured different cannabinoid fractions including THC. A feasibility study was conducted using 477 hemp flower samples to measure various cannabinoid fractions. The novel method potentially eliminates the need for more expensive and time-consuming laboratory testing with trained technical staff, making the testing affordable and reliable. Hemp seeds are a source of healthy food oils and protein-rich food ingredients. ARS researchers in Peoria, Illinois, also conducted an in-house cold pressing of hemp seeds with other scientists in Peoria, Illinois. The resulting hemp oil shows excellent fatty acid composition for a healthy diet, while the defatted hemp meals collected after pressing are used to extract proteins for snack bars or bakery products.
Under Objective 2: ARS researchers in Peoria, Illinois, conducted research on the applications of the above flours, flour components (e.g., oils and proteins), and composites of SMHS grains in various food categories. The lack of food application of SMHS in America is mainly due to the perceived taste, digestibility, or reputation of the grains. To overcome this barrier to consumption, processing technologies must be developed to eliminate unappetizing taste and texture. For some studies, the SMHS flours or components developed under Objective 1 were used as healthy replacements for formulations of commercial food products (baked products, noodles, beverages); in other studies, the SMHS composite materials developed under Objective 1 were tested to ensure that they retain consumers’ acceptability and enhanced nutritional and healthful qualities. Novel composites of SMHS grains and pulses, which are equally healthful and have complementary amino acid profiles, are being tested to develop food ingredients that are nutritionally complete and functional in various food formulations. ARS researchers in Peoria, Illinois anticipate that these innovative SMHS-containing baked products will have nutritional and textural qualities that are comparable to existing all-wheat baked goods. Research was also conducted by adding healthy bean or oat flours or their byproducts to these processed SMHS fractions or flours to achieve nutritional completeness in existing food products and meet the requirements of commercial scale production. These new composites had optimal amino acid profiles to support human health, and they were rich in health-promoting components (dietary fibers, antioxidants, etc.). The composites also provided hydrocolloids, a family of functional components important for food processing and shelf life. These features made our new SMHS composites useful as food ingredients that deliver nutrition without changing the taste, texture, or color of foods loved by Americans. New studies have been initiated on jet cooking composites in our pilot plant. The effect of jet cooking and roasting was studied on yield, quality, and texture of hydrocolloids, protein-rich fractions, and soluble fibers. The natural antioxidants derived from the grains will also be tested in frying oil or baked goods. New and expanded markets for underutilized grains, including their byproducts, are important for improving the profitability of American agriculture. Food applications of these grains were the focus, but applications were also explored on the uses of processed and fractionated components of milling byproducts for non-food applications at the commercial level. ARS researchers in Peoria, Illinois built upon their success in converting soybean hulls into biobased cat litter with new initiatives of converting milling byproducts of SMHS grains into renewable biobased cat litter and other pet care products.
This is the final report for this project which terminated in April 2025. See the report for the replacement project, 5010-41000-182-00D, “Advancing Sustainable Technologies to Improve End-Use Quality of Underutilized and Climate-Resilient Food Crops for Value-Added Food and Consumer Products” for additional information.
Accomplishments
1. Improving silflower’s economic viability through breeding and optimizing farming practices. Silflower has drawn great interest as a potential new oilseed crop due to its drought and stress resilience, high squalene level (a potentially commercially viable alternative to shark liver oil-based squalene that is widely used in vaccines and skincare products), and healthy fatty acids and phytochemicals beneficial to human health. However, there are still many challenges that need to be addressed before the crop can be adopted in the United States as an economically profitable cash crop. Current research focuses on breeding and optimal farming practices. This study aimed to understand the effect of growing conditions such as temperature and precipitation on oil properties from different breeds of silflower. ARS scientists in Peoria, Illinois, analyzed silflower seeds from different plant varieties grown at three different locations in 2022 and 2023. They found that several important economic traits of silflower seeds do vary with breeds and environment (rainfalls and temperature variation). This finding will help silflower farmers to better manage their crop planting and maintenance and for breeders to develop new breed lines with high oil quality (including high squalene content) and less chlorophyll in the oil and extracted protein meal.
2. Different crude hempseed oil extraction methods affect final oil quality. Hempseed oil is valued as a promising healthy oil from hemp crop. Crude hempseed oil, extracted using either solvent or mechanical presser, contains pigmented compounds that cause oil degradation and unacceptable colors. However, removal of these pigmented compounds is costly and requires additional material input that ultimately leads to disposal problems. ARS scientists in Peoria, Illinois, investigated treatments of both mechanical-extracted and solvent-extracted crude hempseed oils and identified the optimal process for the best hemp seed oil quality. They found that mechanically extracted hemp seed oil requires the least amount materials to remove the pigmented compounds, exhibits stable oil quality, and retains the largest number of antioxidants. This finding will help hempseed oil processors to optimize their hempseed oil refining processes to produce high-quality and shelf-stable edible oil for health-conscious consumers.