Drying is a critical process in the preservation of agricultural products such as fruits and nuts, playing a key role in extending shelf life and reducing postharvest losses

Oregon State University received a $610,997 Project Grant from the U.S. Department of Agriculture's National Institute of Food and Agriculture under the Agriculture and Food Research Initiative (AFRI, CFDA 10.310) program, effective September 1, 2025 through August 31, 2028. The project develops and evaluates innovative drying technologies for agricultural products, specifically examining cold plasma pre-treatment as a method to enhance moisture removal in fruits and nuts. The research combines cold plasma pre-treatment with conventional hot air drying and radiofrequency-assisted drying techniques, using grapes and hazelnuts as model systems to optimize drying rates, energy consumption, product quality, microbial safety, and sensory attributes.

The primary deliverables include comprehensive technical assessments measuring energy efficiency gains, greenhouse gas emission reductions, and production cost savings compared to conventional drying methods, along with environmental and economic sustainability evaluations. The project incorporates close collaboration with industry stakeholders to ensure commercial viability and facilitate technology adoption. Additionally, the award supports workforce development through training of food scientists and engineers and the establishment of industry-academic partnerships to advance sustainable innovation in food processing, positioning the research to address the food industry's growing need for energy-efficient preservation technologies.

However, drying is also one of the most energy-intensive operations in food manufacturing, accounting for a significant share of processing-related energy use. This high energy demand leads to higher production costs, increased carbon emissions, and long drying times, especially for foods with natural moisture barriers like skins or shells that hinder water transfer.as the food industry faces increasing pressure to reduce its environmental footprint and adopt more energy-efficient technologies, there is a growing need for innovative and sustainable drying methods. This project explores the use of cold plasma, a type of low-temperature ionized air, as a novel way to pre-treat fruits and nuts before they are dried. This pre-treatment helps modify surface structures of food, facilitating faster moisture removal during subsequent drying. The research will evaluate and optimize the effectiveness of cold plasma pre-treatment in combination with conventional hot air drying and radiofrequency-assisted drying, using grapes and hazelnuts as model systems. Key metrics will include drying rate, energy consumption, product quality, microbial safety, and sensory attributes. In parallel, environmental and economic assessments will be conducted using sustainability evaluation tools. The project also involves close collaboration with industry stakeholders to ensure practical relevance and facilitate potential adoption. The ultimate goal is to develop a more sustainable drying approach that lowers energy use, reduces greenhouse gas emissions, decreases production costs, and delivers high-quality dried products. In addition, the project will contribute to workforce development by training future food scientists and engineers and fostering industry-academic partnerships to support sustainable innovation in food processing.