Irwin Donis-Gonzáles

Irwin Donis-Gonzáles

Position Title
Assistant Cooperative Extension Specialist

Biological and Agricultural Engineering


Donis-Gonzáles, an assistant Cooperative Extension specialist in the Department of Biological and Agricultural Engineering, specializes in postharvest systems engineering. Donis-Gonzáles completed his Ph.D. in biosystems and agricultural engineering at Michigan State University (MSU). He was a postdoctoral associate at MSU prior to joining the UC Davis faculty in 2015.

Research interests: 

Postharvest engineering, produce handling, agriculture and food storage operations, agricultural produce storage, produce drying, traceability, processing of agricultural commodities, agricultural produce and food quality, agricultural produce and food safety

Brief overview: 

In agriculture, postharvest handling is the stage of production immediately following harvest. Postharvest includes transporting, temperature management, drying, cleaning, sorting and packing of fresh agricultural produce. 

The goal of my program is to research and effectively implement postharvest engineering strategies to reduce energy consumption while ensuring agricultural produce quality and safety. These are critical issues for the fresh fruit and vegetable market in California and the world, as well as the dried fruit, tree nut, and rice industries. 

Postharvest engineering strategies include the development of improved cooling methods, better packaging and handling systems, and an in-depth understanding of what mechanisms impact the loss of quality or safety in agricultural produce. With better postharvest handling, we can improve food security by minimizing agricultural produce losses, which also reduces food waste and energy consumption.

Current projects:

  • Developing a micro-computed tomography method to visualize the microstructure of food
  • Improving walnut quality and drying efficiency through implementation of a two-stage drying and ventilated storage system
  • Investigating usage of different desiccant (hygroscopic) salts for optimized dry produce storage
  • Developing a computer vision system to assess walnut kernel surface color
  • Evaluating water management techniques and fertilizer rates in onion postharvest quality in California low desert areas
  • Developing a better understanding of sweet cherry postharvest cracking in California and potential strategies to reduce its incidence