Location: Healthy Processed Foods Research
2020 Annual Report
Objectives
The goal of this research is to continue the investigation, development and commercialization of several new infrared (IR) and ultraviolet (UV) based processing technologies including infrared drying, dry blanching, sequential infrared (IR) dry-blanching/dehydration and hot air-drying (SIRDBHAD), and
combined IR and UV disinfection, and IR dry-peeling of specialty crops. Further goals of this research are to use new process technologies including microwave, solar thermal, vacuum forming, casting, extrusion, pasteurization, and homogenization, alone or in combination, to add value to specialty crops. Specific objectives are listed below:
Objective 1: Enable new, efficient and sustainable commercial infrared and ultraviolet based methods for processing specialty crops to improve food quality, value and safety.
Sub-objective 1.1 Investigate and commercially demonstrate an energy efficient drying technology for producing high quality nuts.
Sub-objective 1.2 Investigate, demonstrate, and commercialize a novel IR technology for producing healthy crispy snacks.
Sub-objective 1.3 Develop IR heating and ultraviolet (UV) technology for improved drying efficiency and safety of nuts.
Sub-objective 1.4 Develop sustainable IR peeling technologies for fruits and vegetables.
Objective 2: Enable economical, input-efficient and sustainable commercial microwave and solar thermal methods for processing specialty crops while improving product quality and value.
Sub-objective 2.1. Develop microwave systems for drying and extracting high-value compounds from specialty crops and their co-products.
Sub-objective 2.2 Develop a medium-scale solar thermal cabinet dryer with the capability to operate 24 hours a day during specialty crop harvest periods.
Sub-objective 2.3 Develop solar thermal alternatives for heat-intensive specialty crop processing unit operations beyond cabinet drying.
Objective 3: Enable novel, value-added commercial forming, casting and extrusion methods for processing fruits, vegetables and legumes with improved food safety and nutrition.
Sub-objective 3.1 Develop vacuum forming technologies that can be implemented to increase utilization and consumption of specialty crops and their co-products in a variety of nutritious and value-added forms.
Sub-objective 3.2 Apply the tools of nanoscience to the casting of edible films to improve safety, extend shelf-life and improve quality.
Sub-objective 3.3 Develop healthy and sensory enhanced, ready-to-eat extruded healthy foods from legumes, specialty crops, cereals, fruits and vegetables and their fractions.
Objective 4: Enable new, commercial methods of pasteurizing legumes and specialty crop-based beverages and yogurts, for improved flavor, bioactives and shelf life.
Approach
The research and development of new processing technologies can add value to
specialty crops through the development of new foods containing up to 100%
specialty crop based ingredients with enhanced healthfulness, convenience, and overall consumer appeal. Increased consumption of nutritious fruit, vegetable, nut, and legume based foods will improve the American diet and reduce the prevalence of obesity in our nation. This research will also improve profitability for U.S. growers and processors by increasing demand for specialty crops and by developing new value added products with high potential for export. Development of sustainable processing technologies which result in energy and water savings is another benefit of this research. Food safety will also be improved. Infrared, ultraviolet, microwave, solar thermal, forming, casting, extrusion, pasteurization and high pressure homogenization processing technologies will be explored, alone and in combination, to form novel value added food systems. Ultimately, effects of processing on final product properties will be characterized and processing methodologies optimized to maximize final product quality, safety, nutritional value, and sensory properties. An extensive network of collaborators from universities, research institutes in other countries, commodity organizations, medical research labs and the food industry, as well as sizable grants from Federal and State agencies and industry groups, will be used to support and insure a high degree of impact resulting from the research proposed in this project plan. Scientific impact will ultimately be achieved through scientific publications, patents, new mathematical models and transference of these technologies into commercialization.
Progress Report
This is the final report for project 2030-41000-064-00D, which has been replaced by new bridging project 2030-41000-066-00D. For additional information, see the new project report.
Objective 1 was completed during the life of the project. Researchers in Albany, California, along with collaborators at the University of California, Davis, designed and built equipment to use infrared (IR) energy to dry walnuts and save energy during processing. This equipment (10-15 tons per hour capacity) was installed at a commercial partner’s facility, where it was tested, and product quality was optimized. A portion of the work was supported by a California Energy Commission (CEC) grant. The ARS researchers also worked with a commercial partner to develop a sequential IR dry blanching and hot air-drying process to produce healthy fruit and vegetable snacks. With financial support from a second CEC grant and a commercial partner, commercial-scale equipment was built, various fruit- and vegetable-based crispy healthy snacks were produced, and the performance of the system was quantified. The patented technology was licensed by a commercial Cooperative Research and Development Agreement (CRADA) partner. The effectiveness of IR heating for processing pistachios was also studied, with the results showing that this technology has great potential for drying and improving food safety of this crop. In addition, researchers completed studies comparing the performance of electrical vs. catalytic IR emitters for scale-up of the processing of grains. In the area of ultraviolet (UV) light in food processing, researchers determined the intensity and duration of UV-B light needed to elicit Vitamin D production in mushrooms. Finally, for IR peeling, it was found that adding flame heating before IR heating significantly reduced the overall heating time needed for peeling tomato, which further improved the throughput of the process compared to IR heating alone, as demonstrated on a pilot-scale system.
Researchers made substantial progress on Objective 2 during the project period. Microwave-assisted extraction of valuable components from specialty crop co-product streams (olive pomace, in particular) was explored. The sun-drying rates of apricots, nectarines, and tomatoes were predicted from real-time measured ambient weather variables. The effects of sulfiting pretreatment and cabinet materials on the sun-drying performance of apricots were investigated, and other stone fruits were dried using a novel tray design that increases the phytosanitary quality of the product. With a CRADA partner, researchers tested the potential of novel solar driers to dry fruit at a commercial farm in California. In partnership with collaborators at the University of California, Merced, ARS researchers developed a novel solar thermal drum dryer and tested it to dry fruit and vegetable purees and pomaces. The dryer derives 100% of its thermal energy from sunlight. This work was supported by a grant from the California Department of Food and Agriculture.
Significant progress was also made on all Objective 3 sub-objectives during the course of the project. Research continued with Children’s Hospital Oakland Research Institute on metabolic balance/obesity prevention bars. After the completion of several clinical trials and the ARS researchers’ improvement of the sensory properties of the bars, the bar that was developed with a CRADA partner was licensed, and a company began to market it commercially. In a partnership with local rural high school students, researchers used vacuum forming to make fruit snacks using locally sourced pear, pomegranate, and kiwi fruit. Researchers investigated and developed applications of nanoscience to edible films, and a project on blow spinning of nanofibers from food materials was completed with support from a USDA - National Institute of Food and Agriculture (NIFA) grant. In collaboration with researchers from Instituto Politécnico Nacional (San Isidro, Mexico), ARS researchers determined the effect of the concentration of cellulose nanocrystals on the microstructure of canola protein isolate edible films. In addition, a Binational Agricultural Research and Development Fund grant supported ARS scientists’ and their Israeli collaborators’ research on UV treatment of mushrooms and mushroom waste. Significant progress was made on developing ready-to-eat lentil-based, gluten-free extruded snacks from novel formulations containing California rice and an underutilized tiger nut (Cyperus esculentus), which is rich in omega-3, short chain fatty acids, and dietary fiber.
Considerable progress was made under Objective 4 by identifying and evaluating a variety of legumes and specialty crops for the potential improvement of flavor, taste, appearance, viscosity, shelf life, and overall nutritional and functional properties of plant-based beverages and yogurts. The effects of different food ingredients such as pea protein, rice, natural gums, honey, brown sugar, low-caloric sweeteners, and different flavors were assessed. Research on plant-based beverages was more extensively studied, due to textural limitations of the yogurt products. Water absorption index, water solubility index, water hydration capacity, viscosity, visual stability index, and sensory evaluation were used to characterize the different beverages’ formulations. The average viscosity within a particular shear rate range provided an accurate way to evaluate and categorize the protein concentration and dietary fiber of the beverages. Particle size reduction protocols were developed to generate particles in the range of < 5 µm by a combination of techniques, including homogenization, sonification, and high pressure microfluidization. The viscosity, pH, and sensory properties of the novel beverages were found to be in acceptable ranges for this type of product. ARS researchers collaborated with visiting scientists from the University of Dijon and LaSalle, France in the development of the value-added plant-based beverages and yogurts.
Substantial progress was realized on a number of subordinate projects, all of which supported the objectives of the base-funded research program.
Toward the general project objectives of developing new sustainable processing technologies to produce healthy, value-added foods from specialty crops, a USDA-NIFA Agriculture and Food Research Initiative project on isochoric (constant-volume) freezing was initiated. ARS scientists collaborated with engineers at the University of California, Berkeley, to develop a novel freezing technology to improve the quality, nutrition, and safety of foods while reducing energy consumption during processing. Researchers completed experiments measuring the effects of isochoric freezing on cherries, spinach, fish, and tomatoes. These studies indicated that isochoric freezing produces foods with higher quality than conventional freezing in terms of texture, color, structure, and nutritional value. Researchers also found that isochoric freezing has the potential to inactivate food pathogens including Listeria monocytogenes, Salmonella typhimurium, and Escherichia coli suspended in buffer solution under certain time/temperature conditions. The team demonstrated that isochoric freezing has the potential to substantially reduce energy consumption during freezing.
In support of Objective 1, and in conjunction with a CRADA partner, a crunchy puffed oat snack product was developed as an alternative to nutrient-poor snack foods. The collaborators originally approached ARS researchers with the idea of “popcorn” oats (a puffed oat product), however oats themselves could not be popped due to low starch content. Thus, a crunchy “corn nut” like oat product was developed. It was discovered that IR heating could rapidly gelatinize starch in the oat, which allowed further processing into an expanded crunchy oat snack. The product was optimized and characterized, and a patent was filed in 2018. The CRADA partner was awarded a Small Business Innovation Research grant in 2019. Under this grant, commercial production equipment was procured, and sensory analysis of commercially-produced and -packaged product was conducted in 2020.
Also, in support of Objective 1, ARS researchers and CRADA partner scientists explored ways to improve the drying process for brewers spent grains – a co-product of beer brewing. In the process, it was discovered that not only was IR drying energy efficient, it added a special toasted note to the grain. A patent was filed in 2017 and granted in 2020.
Toward aspects of Objectives 2 and 3, ARS scientists and a CRADA partner sought to find uses for olive pomace, which is the solid co-product of olive oil processing. The pomace is high in antioxidants and has potential for high food value. In 2018, the researchers began to examine ways to de-pit, stabilize, and dry the pomace. It was found that a finisher commonly used for fruit puree could be used very efficiently to remove the pit fragments from the pomace, yielding a bitter but edible puree. Commercially-produced pomace was processed for pit removal and then analyzed for moisture and antioxidant content. In the 2019 season the processing was moved to the CRADA partner’s facility; the samples stabilized on-site were taken to the ARS lab for analysis.
Lastly, ARS researchers worked with a CRADA partner whose plant-based beverage is based on pea protein. The main concerns for this product are flavor and texture. In support of Objective 4, ARS researchers investigated different drying technologies with varying time/temperature combinations to determine their effect on flavor of the final product and solubility of the pea protein. Processing parameters were narrowed down and testing of pH treatments on a new pea protein was initiated.
Accomplishments
1. New isochoric freezing technology provides foods with similar quality to fresh foods while reducing energy consumption. Current freezing technologies result in thawed products with poor quality, which decreases consumer approval for frozen foods; in addition, conventional freezing processes are energy-intensive. Therefore, there is a need to develop a new freezing technology that ensures high quality as well as minimal energy use. ARS researchers at Albany, California, in collaboration with engineers from the University of California, Berkeley, developed a new freezing method called isochoric freezing, that allows food preservation at subfreezing temperatures without any ice damage. As a result, isochoric freezing preserves the quality and nutritional properties of foods to a greater extent than conventional freezing. The researchers also used fundamental thermodynamic analyses to demonstrate that isochoric freezing requires up to 70% less energy compared to conventional freezing. Isochoric freezing is poised to transform the global frozen food market, valued at over $250 billion.
2. Tiger nut: a gluten-free ingredient in healthy lentil-based extruded snacks. The number of people diagnosed with celiac disease has increased in recent years, and the disease is a major public health challenge worldwide. This has promoted an increase in food market demand for gluten-free (GF) products by consumers. To address this need, ARS researchers in Albany, California, developed ready-to-eat lentil-based, gluten-free extruded snacks from novel formulations containing California medium size rice and the nonconventional and underutilized tiger nut (Cyperus esculentus). Tiger nut is rich in omega-3, short chain fatty acids and dietary fiber. The ready-to-eat, gluten-free extruded snacks could provide a healthy alternative to commercial snacks (made mainly from gluten-containing cereal mixes), for millions of people suffering from celiac disease and enter into the increasing food market demand for gluten-free products.
Review Publications
Quispe-Fuentes, I., Vega-Galvez, A., Aranda, M., Poblete, J., Pasten, A., Bilbao-Sainz, C., Wood, D.F., McHugh, T.H., Delporte, C. 2020. Effects of drying processes on composition, microstructure and health aspects from maqui berries. Journal of Food Science and Technology. 57:2241-2250. https://doi.org/10.1007/s13197-020-04260-5.
Bilbao-Sainz, C., Sinrod, A., Dao, L.T., Takeoka, G.R., Williams, T.G., Wood, D.F., Bridges, D.F., Powell-Palm, M., Ukpai, G., Chiou, B., Wu, V.C., Rubinsky, B., McHugh, T.H. 2019. Preservation of spinach by isochoric (constant volume) freezing. International Journal of Food Science and Technology. 55(5):2141–2151. https://doi.org/10.1111/ijfs.14463.
Bilbao-Sainz, C., Sinrod, A., Chiou, B., McHugh, T.H. 2019. Functionality of strawberry powder on frozen dairy desserts. Journal of Texture Studies. 50(6):556-563. https://doi.org/10.1111/jtxs.12464.
Da Silva Alves, P.L., Berrios, J.D., Pan, J., Ramirez Ascheri, J.L. 2018. Passion fruit shell flour and rice blends processed into fiber rich expanded extrudates. CyTA - Journal of Food. 16(1):901-908. https://doi.org/10.1080/19476337.2018.1503618.
Poverenov, E., Arnon-Rips, H., Zaitsev, Y., Bar, V., Danay, O., Horev, B., Bilbao-Sainz, C., McHugh, T.H., Rodov, V. 2018. Potential of chitosan from mushroom waste to enhance quality and storability of fresh-cut melons. Food Chemistry. 268:233-241. https://doi.org/10.1016/j.foodchem.2018.06.045.
Milczarek, R.R., Vilches, A.M., Olsen, C.W., Breksa III, A.P., Mackey, B.E., Brandl, M. 2020. Physical, microbial, and chemical quality of hot-air-dried persimmon (diospyros kaki) chips during storage. Journal of Food Quality. 2020. https://doi.org/10.1155/2020/7413689.
Ban, Z., Horev, B., Rutenberg, R., Danay, O., Bilbao-Sainz, C., McHugh, T.H., Rodov, V., Poverenov, E. 2018. Efficient production of fungal chitosan utilizing an advanced freeze-thawing method; quality and activity studies. Food Hydrocolloids. 81:380-388. https://doi.org/10.1016/j.foodhyd.2018.03.010.
Liu, F., Saricaoglu, F., Avena-Bustillos, R.D., Bridges, D.F., Takeoka, G.R., Wu, V.C., Chiou, B., Wood, D.F., McHugh, T.H., Zhong, F. 2018. Preparation of fish skin gelatin-based nanofibers incorporating cinnamaldehyde by solution blow spinning. International Journal of Molecular Sciences. 19(2):618. https://doi.org/10.3390/ijms19020618
Zhu, L., Olsen, C.W., McHugh, T.H., Friedman, M., Levin, C.E., Jaroni, D., Ravishankar, S. 2020. Edible films containing carvacrol and cinnamaldehyde inactive Escherichia coli O157:H7 on organic leafy greens in sealed plastic bags. Journal of Food Safety. 40(2). Article e12660. https://doi.org/10.1111/jfs.12758.
Toyofuku, N., Mahoney, N.E., Haff, R.P. 2019. Aflatoxin cross-contamination during mixing of shelled almonds. Journal of Food Processing and Preservation. 44(2). https://doi.org/10.1111/jfpp.14330.
