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ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Bioproducts Research » Research » Research Project #427364

Research Project: Bioproducts from Agricultural Feedstocks

Location: Bioproducts Research

2020 Annual Report

The demand for agricultural feedstocks is growing as global demand for food is ever increasing and efforts mount to create alternatives to petroleum products that feed global warming. The goal of this project plan is to use biopolymers to develop sustainable technologies and bioproducts that will benefit the U.S. and that will not negatively impact food reserves. This plan highlights the use of nonfood fibers and crop waste to create new bioproducts and help improve the efficiency in utilizing agricultural commodities via the following objectives: Objective 1: Enable, from a technological standpoint, new commercial value-added biobased materials. a. Utilize conventional and novel processing technologies to produce and characterize nanofibers from biopolymers and investigate potential applications. b.Utilize biopolymers to encapsulate/deliver beneficial soil microbes that improve crop production. Objective 2: Enable new commercial materials based on biopolymers and biobased fillers. a. Develop fiber-reinforced composite materials. b. Develop value-added bioproducts from torrefied crop waste. c. Develop value-added bioproducts from almond, grape and citrus waste.

The overarching approach will be to provide data, technology and prototypes that will not only result in novel bioproducts but also address important agricultural needs including the need for higher crop production, the need for more sustainable farming practices, the need for alternatives to petroleum-based products and the need for new innovations such as nanotechnology. The first approach is development of composite materials that encapsulate beneficial microbes to be used to reduce the inputs of conventional fertilizers and petroleum-based pesticides. A co-development as part of this approach is production of humic acid from renewable resources such as torrefied crop waste to augment soil health. Humates will be used as soil amendments to improve soil fertility and crop production. Also, nanofibers from aqueous solutions of biopolymers will be made and characterized by developing new processes to make nanofibers from a wide array of biopolymers. Bioproducts made using the nanofibers will include controlled-release devices and sensors. Objective 2 is aimed at developing bioproducts from nonfood agricultural products, namely plant fibers and crop waste. The group will apply expertise in dispersing plant fibers in biopolymer matrices and in inorganic binders. The anticipated bioproducts developed in Objective 2a include compression molded food service products containing more than 60% fiber using biopolymers as binders. We will also create lightweight rigid foam products by dispersing plant fibers in inorganic binders including Portland cement and gypsum. California has one of the most diverse agricultural industries in the world and ranks first in production in terms of cash receipts ($43 billion), but also leads in the output of crop waste and residues. Diverse agricultural byproducts such as almond hulls, grape pomace, citrus peel waste, etc., which are concentrated at processing plants and often carry a cost for disposal, will be converted into higher value products. Objectives 2b, and 2c specifically address this need. The anticipated products include black filler for PET plastics and pelletized coal dust made using inexpensive biopolymer binders such as citrus waste and gums from almond hulls. Other bioproducts include essential oils and antioxidants extracted from seeds processed from grape pomace.

Progress Report
This is the final report for Project 2030-41000-058-00D, "Bioproducts from Agricultural Feedstocks," which has been replaced by new Project 2030-41000-067-00D, "Bioproducts and Biopolymers from Agricultural Feedstocks." The present terminating project successfully built upon the prior successes in bioproduct development from renewable resources, agricultural commodities, and crop waste and was facilitated by partnerships and collaborations with industry, academia, commodity commissions, and ARS colleagues. There were changes in research staff during the project including the retirement of one senior scientist early on and the eventual replacement with a junior scientist. Despite the staff changes, all project plan objectives were met, and significant accomplishments were achieved in both technology transfer and peer-reviewed scientific publications. In support of Objective 1 and Sub-objective 1A, prior research in our laboratory successfully developed a novel method called solution blow spinning (SBS) for making nanofibers from polymer solutions. Much of the nanofiber work was accomplished in a collaborative research effort with Brazilian colleagues and with ARS colleagues in Albany, California. Specific research activities included fundamental studies to determine how SBS processing parameters affected the thickness and morphological features of nanofibers spun from poly(lactic acid) (PLA) polymer solutions. The optimal settings in nozzle air-pressure, polymer concentration, and feed rate for obtaining the smallest diameter fibers were determined using a Box-Behnken experimental design as described in the project plan. In addition, nanocomposite fibers were made by incorporating cellulose nanocrystals (CNCs) in nanofibers of PLA. A fraction of the cellulose nanocrystals was exposed on the surface of the PLA fibers thus making them more hydrophilic. Such composites may have potential application as filtering membranes or adsorbents. The nanofiber work explored ways to produce CNCs at a lower cost which would enable their broader use by industry. A two-step process was developed to extract CNCs from pulp fiber. The pre-treatment consisted of incubating the fiber in low-cost bacteria-rich digestate followed by high-shear mixing to obtain cellulose micro/nanofibers. The digestate treatment partially removed amorphous components of the pulp fiber thereby decreasing micro/nanofiber diameters and enhancing the crystalline content. The results demonstrate the effectiveness of digestate treatments coupled with high-shear mixing to produce mixtures of micro- and nanofibers. New sources of CNCs with novel properties were also investigated with Brazilian colleagues including a cactus native to Northeastern Brazil. Ceramic nanofibers have various industrial uses and are typically made with polyacrylonitrile (PAN) using hazardous solvents. Ceramic nanofibers were successfully made by an SBS process using polyvinylpyrrolidone and a very safe solvent, ethanol. The fiber samples were carbonized at 550°C in nitrogen. The ceramic nanofibers had properties similar to ceramic nanofibers made with PAN. These fibers had a cotton-like morphology and were produced at higher output rates than those achieved by other current spinning technologies. Ceramic nanofibers fabricated using the safer materials and higher production process could significantly reduce costs and increase the likelihood of commercial viability. ARS colleagues in Albany, California, received a grant to explore possible food uses of nanofibers. Nanofibers were made by SBS using solutions of the corn protein, zein, in acetic acid. The SBS process was also used to form nanofibers from food-grade gelatin extracted from mammalian and fishery byproducts. While the mammalian gelatin did not form acceptable nanofibers, much better results were obtained with the fish gelatin. Food-grade nanofibers from zein and/or fish gelatin could be useful as carriers for active compounds. In support of Sub-objective 1B, an encapsulation media for soil microbes was developed and patented. The patent was licensed by two companies to explore commercialization. In addition, a grant from the California Department of Food and Agriculture was received to conduct field trials to assess the effect of encapsulated beneficial soil microbes on crop production. The field trials revealed that the treatments did not significantly improve crop production under the conditions tested. Nevertheless, greenhouse trials under more controlled conditions revealed that specific soil microbes could significantly improve plant growth. A phosphorous solubilizing bacterial strain was tested in stringently controlled greenhouse trials. Microbial treatments significantly improved the growth of corn plants. In support of Sub-objective 2A, new fiber-based composite materials were developed. Starch/fiber composite sheets were thermoformed into food packaging that would be both moisture and oil resistant. A second starch/fiber composite foam material was developed that could be formed into sheets or molded into shapes and containers. The foam had excellent thermal properties and was readily biodegraded. These composite materials are being commercialized by an industrial partner. A baking process was used to study starch/fiber composites for food packaging applications. This research was conducted in cooperation with scientists in Mexico. The starch used in the study was from locally sourced plantains and chayotextle tubers. The results of the trials showed that lightweight foam made of locally sourced starches and fiber could be used for food packaging applications. Agricultural fibers were also tested and evaluated in composite materials developed cooperatively with colleagues in Brazil. Specifically, a process was developed for incorporating fiber from corn waste, pine, sugarcane bagasse, and eucalyptus polyesters and polypropylene. These composite materials contained significant amounts of plant fibers and could reduce the amount of plastics used in commercial products. A starch-based composite material was developed as a control-release system for agricultural fertilizers. The starch-based pellets can be loaded with nitrogen or other plant nutrients and formed into granules similar to conventional fertilizers. The granules are designed to minimize losses from run-off and leaching. In support of Sub-objective 2B on value-added bioproducts from torrefied crop waste, collaborations were established with various companies and stakeholders to produce torrefied biomass-polymer composites for different applications. Grants were awarded by the Almond Board of California and the California Walnut Board to develop polymer composites containing torrefied almond and walnut shells. The research showed that composites containing torrefied shells were stiffer and had greater thermal stability than that of the neat polymer sample. Up to 30weight% torrefied shells could be incorporated into composites without adversely affecting the mechanical properties. Also, composites containing smaller particles had better thermal and mechanical properties. In addition, a combined torrefaction reactor and compounder system was designed and constructed to produce composites in a single, continuous process. An Innovation grant was awarded to help fund this part of the project. This combined system is a one step process and has the advantage over conventional systems that require separate steps for torrefaction and compounding. A patent application was submitted for this design. The properties of volatiles and solids produced during torrefaction of almond shells were also examined. The energy values of condensates and equilibrium moisture contents of solids were studied and revealed to be accurately predicted from just the mass loss of the entire sample during torrefaction. Computer modeling was used to examine the effects of inorganic species on the torrefaction kinetics of almond and walnut shells. The inorganic species reduced the mass yields of torrefied shells since they catalyzed the decomposition of the shells. A CRADA with an industrial partner was initiated to develop composites that incorporated torrefied sorghum. The results demonstrated that tensile strength of composite materials could be increased by incorporating 10% by weight of torrefied sorghum. In other work, cooperative research with several companies was instrumental in producing pallet and slip sheet prototypes that incorporated torrefied biomass. An Innovation Fund grant was received to help with this part of the project. In yet other work, a grant was awarded to work with a company that makes packaging for produce. The objective of this grant was to design and produce a large scale torrefaction reactor that could ultimately lead to the production of 2,000 tons of torrefied biomass-polymer composites per year. In support of Sub-objective 2C, cooperative research was done with a company that develops and markets agricultural byproducts for the poultry and livestock industries, to strip the outer skin layer from grape seeds. This layer contains large amounts of antioxidants. A novel method was developed to remove the skin layer by using a stone grinding mill. Dried grape seeds were ground for 5 minutes until the seeds changed color. This removed 20% of the outer layer of the seeds. A ground sample was provided to the cooperative company for evaluation. In further support of Sub-objective 2C, a grant was received from a regional commodity board to extract sugars from almond hulls for use as bee food. The effects of temperature and time on the extraction of sugars from hulls using water were examined. The results indicated that most of the sugars were extracted after 30 minutes, even at room temperature. The extracts were fed to honeybees, however, the extracts proved toxic due to the high phenolic content of the extracts.

1. New technology provides moisture and oil resistance for packaging. Per- and polyfluoroalkyl substances (PFASs), known as “forever chemicals” have long been used in paper wraps and food service-ware to provide moisture and grease/oil resistance. However, PFASs have become an environmental and health concern due to their persistence in nature, bioaccumulation, and association with various health conditions. Scientists in Albany, California, have developed two different alternatives to PFASs that are safe for food contact and that biodegrade in many environments. Provisional patents have been filed for both materials. This technology provides manufacturers new options for coating food-service ware.

Review Publications
Castro, J.P., Nobre, J.C., Bianchi, M., Trugilho, P., Napoli, A., Chiou, B., Williams, T.G., Wood, D.F., Avena Bustillos, R.D., Orts, W.J., Tonoli, G.D. 2018. Activated carbons prepared by physical activation from different pretreatments of amazon piassava fibers. Journal of Natural Fibers. 16(7):961-976.
Castro, J., Nobre, J.C., Napoli, A., Trigilho, P., Tonoli, G.D., Wood, D.F., Bianchi, M. 2020. Pretreatment affects activated carbon from piassava. Polymers. 12(7):1483.
Placido, D.F., Dierig, D.A., Cruz, Von, M.V., Ponciano, G.P., Dong, C., Dong, N., Huynh, T.T., Williams, T.G., Cahoon, R.E., Wall, G.W., Wood, D.F., Mcmahan, C.M. 2020. Downregulation of an allene oxide synthase gene improves photosynthetic rate and alters phytohormone homeostasis in field-grown guayule. Industrial Crops and Products. 153:112341.
Bilbao-Sainz, C., Sinrod, A., Powell-Palm, M., Dao, L.T., Takeoka, G.R., Williams, T.G., Wood, D.F., Ukpai, G., Aruda, J., Bridges, D.F., Wu, V.C., Rubinsky, B., McHugh, T.H. 2018. Preservation of sweet cherry by isochoric (constant volume) freezing. Innovative Food Science and Emerging Technologies. 52:108-115.
Ramos, R.R., Siqueira, D.D., Wellen, R., Leite, I., Glenn, G.M., Medeiros, E. 2019. Development of green composites based on polypropylene and corncob agricultural residue. Journal of Polymers and the Environment. 27:1677-1685.
Castro, J.P., Nobre, J.C., Napoli, A., Bianchi, M., Moulin, J.C., Chiou, B., Williams, T.G., Wood, D.F., Avena Bustillos, R.D., Orts, W.J., Tonoli, G.D. 2019. Massaranduba sawdust: a potential source of charcoal and activated carbon. Polymers. 11(8). Article 1276.
Wagschal, K.C., Jordan, D.B., Hart-Cooper, W.M., Chan, V.J. 2019. Penicillium camemberti galacturonate reductase: C-1 xidation/reduction of uronic acids and substrate inhibition mitigation by aldonic acids. International Journal of Biological Macromolecules. 153:1090-1098.
Chiou, B., Cao, T.K., Bilbao-Sainz, C., Vega-Galvez, A., Glenn, G.M., Orts, W.J. 2020. Properties of gluten foams containing different additives. Industrial Crops and Products. 152. Article 112511.
Flynn, A., Torres, L.F., Hart-Cooper, W.M., McCaffrey, Z., Glenn, G.M., Wood, D.F., Orts, W.J. 2020. Evaluation of biodegradation of polylactic acid mineral composites in composting conditions. Journal of Applied Polymer Science. 137. Article 48939.
McCaffrey, Z., Thy, P., Long, M., Oliveira, M., Wang, L., Torres, L.F., Aktas, T., Chiou, B., Orts, W.J., Jenkins, B. 2019. Air and steam gasification of almond residues. Fuel Processing Technology. 7(21):84.
Bilbao-Sainz, C., Thai, T.T., Sinrod, A., Chiou, B., McHugh, T.H. 2020. Functionality of freeze-dried berry powder on frozen dairy desserts. Journal of Food Processing and Preservation. 43(9):e14076.
Giroto, A., Garcia, R.H., Colnago, L.A., Klamczynski, A.P., Glenn, G.M., Ribeiro, C. 2019. Role of Urea and Melamine as synergic co-plasticizers for starch composites for fertilizer application. International Journal of Biological Macromolecules. 144:143-150.
Osorio-Ruiz, A., Avena Bustillos, R.D., Chiou, B., Martinez-Ayala, A. 2019. Mechanical and thermal behavior of canola protein isolate films as improved by cellulose nanocrystals. ACS Omega. 4(21):19172-19176.
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.
Costa Farias, R., Mota, M.R., Severo, L., Medeiros, E., Klamczynski, A.P., Avena Bustillos, R.D., Lima Santana, L., Araujo Neves, G., Glenn, G.M., Rodrigues Menezes, R. 2020. Green synthesis of porous N-Carbon/Silica nanofibers by solution blow spinning and evaluation of their efficiency in dye adsorption. Journal of Materials Research and Technology. 9(3):3038-3046.