The Cutting Edge in Sorting Technology and Harvester Improvement
|
Fig. 1. Fruit image under a hyperspectral transmittance camera using 1070 nm wavelength. Red color indicates bruised tissues, green color for healthy tissues, and blue color for calyx center. |
In the 2018 growing season in Oregon, a fixed hyperspectral transmittance imaging (using 1070 nm) camera was used to detect fruit IBD after sorting. Our study found that ‘Duke’ blueberry harvested by machine had only 30% fruits with no IBD at all, 58% fruits have IBD between 0.1-10%, 8% fruits have IBD between 10-20%, and 4% fruits have more than 20% IBD. These results indicate that sorting did not remove some fruits with significant IBD at more than 10%. Fruit with significant IBD usually became soft after one week in cold storage and have a shorter shelf life. The improvement in sorting technology, especially using NIR imaging, is needed to increase the efficacy of sorting out the IBD fruit.
With the OBC support, Oregon Department of Agriculture has funded a two-year Block Grant for us to continue developing of a modified fresh blueberry harvester. Design changes in using soft materials on the over the row (OTR) machine harvester to reduce fruit IBD has showed promise in our previous studies. Multiple harvesting experiments with a modified OTR harvester from Oregon and Washington in 2018 demonstrated that fruit firmness and pack out equal or are comparable to hand harvested fruit and better than standard OTR harvested fruit. Fruit IBD was also significantly reduced with soft materials on the OTR. The advances in the OTR harvester design along with better sorting technology will bring the machine harvesting for fresh blueberry ever closer to reality.
SPRING 2019 |