2017 ASHS Annual Conference

Blueberry fruit (Vaccinium spp.) are harvested at nearly equal rates through hand and mechanical methods. There is a trend away from hand harvesting due to labor, time, and economical concerns. Current mechanical harvesting methods are primarily used for fruit destined for the processed market due to the high level of damage and reduced storability. There is an interest in developing new blueberry varieties that are tolerant of these levels of damage, and therefore amenable to machine harvesting for the fresh fruit market, however, there is a 10-15 year timeline for these efforts. In the short term, it is necessary to re-engineer machine harvesting methods to reduce the overall level of damage due to berries impacting hard surfaces of the harvester. In our research we simulated impacts onto two different surfaces (a foam pad and a steel plate) of distances known to occur in machine harvesting and processing lines to induce damage (bruising) and evaluated fruit quality post-storage. We showed that the distance a berry falls and the elasticity of the surface onto which a berry impacts has an effect on weight loss and fruit firmness after a four-week storage period. The following year, we used these data to evaluate the ability of a new harvest assist platform with shaking harvesting apparatuses to minimize fruit damage and to determine the effect on post-harvest storability. In these experiments, we found that firmness and internal quality post-storage was affected by the catching surface and the energy supplied to the shaker head, but by far, the greatest impact on quality was from cultivar. These data are being utilized in the current year of this study to continue to refine the design of the harvest-assist platform to minimize bruising and increase storability of semi-machine harvested fruit.