Source: APPLIED MICROWAVE TECHNOLOGY, INC. submitted to NRP
915 MHZ MICROWAVE HEATING TECHNOLOGY FOR ONE PASS DRYING OF RICE
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
SMALL BUSINESS GRANT
Reporting Frequency
Annual
Accession No.
1019716
Grant No.
2019-33610-29821
Cumulative Award Amt.
$100,000.00
Proposal No.
2019-00395
Multistate No.
(N/A)
Project Start Date
Aug 1, 2019
Project End Date
Mar 31, 2021
Grant Year
2019
Program Code
[8.5]- Food Science & Nutrition
Recipient Organization
APPLIED MICROWAVE TECHNOLOGY, INC.
4115 THOMAS DR SW
CEDAR RAPIDS,IA 524045054
Performing Department
(N/A)
Non Technical Summary
The proposal addresses development of an innovative one-pass drying technology that uses 915 MHz microwave heating characteristics to maximize head rice yield (HRY) recovery. Head rice--which is the mass of milled rice kernels that are at least three-fourths of the original kernel length after milling of brown rice--is the high-value portion of processed/dried rice. National revenue losses related to HRY recovery in 2015 translated to ~$240 million (26 million bushels - HRY equivalent). Therefore, the ability to prevent reduction in HRY values is critical to the rice industry and has significant economic impact on rice producers. The investigators propose to demonstrate feasibility of using 915-MHz microwave heating to dry freshly harvested rough rice, in a one-pass process that is not currently attainable using conventional means, by pursuing the following three technical objectives: determine the (1) specific microwave energy required to achieve one-pass drying of rough rice; (2) extent to which microwave energy used affects millability of rice; (3) relationships among supplied specific energy during microwave treatment and the resulting HRY. The level of performance targeted is to achieve one-pass drying to a moisture content of 12.5-13% wet basis with HRY >65%. This level of success from the current average HRY of 58%, which is achieved through conventional multi-pass drying, will translate to a $145 million increase in rice value annually. Following proof-of-concept in Phase 1, the researchers anticipate to perform detailed studies in subsequent phases to optimize quality characteristics of dried rice and move the technology towards commercialization.
Animal Health Component
80%
Research Effort Categories
Basic
10%
Applied
80%
Developmental
10%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
50115302020100%
Knowledge Area
501 - New and Improved Food Processing Technologies;

Subject Of Investigation
1530 - Rice;

Field Of Science
2020 - Engineering;
Goals / Objectives
The long-term goal of this multi-phase SBIR project is to develop, validate, and commercialize next-generation (one-pass) rapid rough rice-drying technology that maximizes head rice yield--thereby significantly improving regional and national food security and processing efficiency. The specific goal of the Phase I SBIR project is to prove the feasibility of the one-pass rice-drying approach based on 915-MHz microwave heating that will improve the rice-drying rate and milling yield, especially the head rice.The central hypotheses are that 1) volumetric heating associated with microwave technology will help reduce moisture content and temperature gradients within individual rice kernels to result in better head rice yields compared to those achieved with air-drying; 2) the high heat fluxes associated with the microwave heating will result in one-pass drying of rough rice, from harvest moisture contents to safe storage moisture content (12.5%); and 3) attainment of the targeted head rice yield will be unaffected by rice cultivar and initial moisture content.
Project Methods
Study to determine required specific energies of microwaves to achieve one-pass drying of rough rice:Our approach will involve procurement of a broad selection of rice types: long-grain hybrid, long-grain-pureline, and medium-grain. For each rice type, one rice cultivars will be selected. The rice types and cultivars will be procured at harvest moisture contents 16 to 22 percent, wet basis. Correlations among the microwave processing parameters and rice characteristics will aid elucidating the effectiveness of the treatments to achieve one-pass drying. The long-grain hybrid rice cultivars will be cv. XL745; long-grain pureline cv. Lakast; and medium-grain cv. Jupiter. These samples will be procured from commercial farms in Northeast Arkansas. The rationale for this task is that a determination of the interactions among microwave processing parameters and rice characteristics will help to establish regimes of microwave energy that maximize moisture removal from the rice to achieve one-pass drying. When the proposed studies for this objective have been completed, we expect the overall outcome to be well defined regimes of microwave specific energy and treatment duration for one pass drying of the studied rice types and cultivars. Study of the extent to which the supplied specific energies of the microwaves affect the milling degree:Our approach will involve microwave and convective air-drying of long-grain hybrid, long-grain pureline, and medium-grain rice and performing milling tests to determine degree of milling, as expressed by correlations between the surface lipid content and duration of rice milling. The rationale for this task is to determine optimal microwave treatment, in terms of specific energy supply and treatment duration, that results to milling degree/surface lipid content (SLC) of 0.4%. The rice industry has associated SLC of 0.4% with optimal head rice yield recovery and better storability of rice. When the proposed studies for this objective have been completed, we expect the overall outcome to form the foundation of updated guidelines for optimal microwave heating doses, in terms specific energy and treatment duration, for maintaining milling degree desired by the rice industry.Determination of the relationships among the supplied specific energies during microwave treatment and the resulting head rice yield: Our approach will involve microwave and convective air-drying of long-grain hybrid, long-grain pureline, and medium-grain rice and performing milling tests to determine differences in head rice yields. The rationale underlying this objective is that its successful completion will provide sets of processing parameters and product characteristics for maximizing head rice yield during the microwave drying. When the proposed studies for this objective have been completed, we expect the overall outcome to be "process guidelines for rice drying using microwaves." The new guidelines will clearly define the optimal conditions for successful one-pass drying of rough rice while maintaining head rice yields at levels comparable to or better than conventional drying methods (~58%).

Progress 08/01/19 to 03/31/21

Outputs
Target Audience:Graduate students Rice Growers Research Scientist and Engineers Educators & Goverment Organizations Extension agents Rice Processors Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project has provided opportunity for two graduate students and a support personell with post-doc level expertise to learn basics and application of microwaves to rice drying. In addition, we have communicated in a trade magazine the application of this technology in the rice industry. The students participated in writing the magazine; this was a great training effort to improve their writing and public speach skills. How have the results been disseminated to communities of interest?Two abstract for conferences (American Society of Biological & Agricultural Engineer's conference and the NC-213 Annual meetin); a magazine write-up. we also conducted online presentations to stakeholders with inquiry about use of the technology to dry parboiled rice to 5% moisture content for rice flour production. Dissemination was also done via publications below; Manuscripts Bruce RM, Atungulu GG*, Sadaka, S., & Smith D. (2021). Impact of specific energy input of a 915MHz microwave dryer on quality, functional and physicochemical properties of different rice cultivars. Cereal Chemistry (accepted for publication). Bruce RM, Atungulu GG*, Sadaka, S., & Mauromoustakos, A. Impact of harvest moisture content and milling duration on physicochemical properties of rice dried at 915 MHz microwave frequency. (under construction) Conference Presentations Bruce RM, Atungulu GG*. 915 MHz microwave heating technology for one pass drying of freshly harvested high moisture rough rice. ASABE, Virtual & On Demand, 13 - 15 July 2020. Bruce RM, Atungulu GG*. Microwave specific energy impact on the quality, functional and physicochemical properties of different rice cultivars. Cereals and Grains conference, Virtual, 25 October - 13 November 2020. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Major research findings for accomplished Microwave specific energy had a significant impact on rice quality and physicochemical properties such as moisture removal, head rice yield, pasting properties and resistant starch content. Setback and final viscosity increased while peak viscosity decreased with increasing specific energies. Kernel surface lipid content and protein content slightly decreased with increasing specific energies although specific energy did not have a significant effect on these responses. Resistant starch content decreased with increasing specific energy for hybrid rice. In terms of functional properties, specific energy had no significant effect on oil and water absorption capacities of microwave dried rice Specific energy of 525 kJ.[kg-grain]-1 (power-5kW, heating duration-3.5min) was predicted (using statistical models) as the most suitable for drying medium grain rice Titan and long grain hybrid XL753 based on physicochemical properties relative to the control samples. Rice growing location had a significant effect on the physicochemical properties of long grain hybrid rice dried using the 915 MHz industrial microwave dryer. Therefore, changes in the properties of rice dried using the 915 MHz microwave should not only be attributed to the effect of microwave drying parameters (power and drying duration) but also the growth history of the rice. It is recommended that the cooking, storage, and sensory properties of rice dried at the desirable specific energy of 525 kJ.[kg-grain]-1 (power 5 kW, heating duration 3.5 min) be investigated to fully understand the effects of this technology on rice eating characteristics and consumer preference. Rice milling duration had a significant impact on the surface lipid content, trough viscosity and whiteness index of rice dried using the 915 MHz microwave. Milling duration had moderate negative and positive correlations with surface lipid content and whiteness index, respectively. On the contrary, milling duration did not significantly influence the head rice yield, crude protein content, starch damage, peak viscosity, and final viscosity. Harvest moisture content had a significant effect on the head rice yield, surface lipid content, final viscosity, trough viscosity, peak time, and moisture points removed during microwave drying. We recommend that desirable milling durations based on cultivar, harvest moisture content and microwave specific energy should be selected for rice processing.

Publications

  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Bruce RM, Atungulu GG*, Sadaka S, Smith D. 2021. Impact of specific energy input of a 915 MHz microwave dryer on quality, functional, and physicochemical properties of different rice cultivars. Cereal Chemistry, 00, 1-14. DOI: 10.1002/cche.10398
  • Type: Journal Articles Status: Other Year Published: 2021 Citation: Bruce RM, Atungulu GG*, Sadaka, S., & Mauromoustakos, A. Impact of harvest moisture content and milling duration on physicochemical properties of rice dried at 915 MHz microwave frequency. (under construction)
  • Type: Conference Papers and Presentations Status: Other Year Published: 2020 Citation: Bruce RM, Atungulu GG*. 915 MHz microwave heating technology for one pass drying of freshly harvested high moisture rough rice. ASABE, Virtual & On Demand, 13 â¿¿ 15 July 2020.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2020 Citation: Bruce RM, Atungulu GG*. Microwave specific energy impact on the quality, functional and physicochemical properties of different rice cultivars. Cereals and Grains conference, Virtual, 25 October â¿¿ 13 November 2020.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2020 Citation: Atungulu GG. 2020. Coating, cooling and drying of Petfood. Petfood Forum Petfood Essentials reimagined into an online short course launched November 3, 2020.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2020 Citation: Atungulu GG. 2020. Rice processing and postharvest systems engineering. Invited seminar, Kansas State University, Grain Science, April, 23, 2020.