Skip to main content
ARS Home » Northeast Area » Kearneysville, West Virginia » Appalachian Fruit Research Laboratory » Innovative Fruit Production, Improvement, and Protection » Research » Publications at this Location » Publication #310620
Title: Measure of mechanical impacts in commercial blueberry packing lines and potential damage to blueberry fruit

Author
item XU, RUI - University Of Georgia
item Takeda, Fumiomi
item KREWER, GERARD - Krewer Consulting
item LI, CHANGYING - University Of Georgia

Submitted to: Postharvest Biology and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/15/2015
Publication Date: 8/4/2015
Citation: Xu, R., Takeda, F., Krewer, G., Li, C. 2015. Measure of mechanical impacts in commercial blueberry packing lines and potential damage to blueberry fruit. Postharvest Biology and Technology. 110:103-113.

Interpretive Summary: Blueberry harvesting and processing of harvested fruit in packing houses have become increasingly mechanized and automated. A mechanical blueberry harvester can harvest more than 1,000 lbs/hour, whereas a hand picker can harvest only 10 to 15 lbs/hour. In the packing house, electronic color sorter and a soft-fruit sorter can sort blueberries at a rate that previously required 30 or more workers to manually sort. As mechanization and automation have increased, fruit bruising and internal damage are contributing to the loss of fruit quality and postharvest shelf life. In this study, impacts created by commercial blueberry packing lines were measured quantitatively using a miniature instrumented sphere with size and weight of a real blueberry. It recorded impacts encountered by blueberries as fruit moved on the transfer belt either by rolling or dropping through a series of packing line equipment. Laboratory tests determined the relationship between the impact level and the bruise rate of the fruit which were useful for accurately estimating the bruise potential of each of the packing line components. The potential for bruise damage tended to be high at some transfer points where blueberries dropped greater than or equal to 30 cm onto inclined stainless steel surfaces. Padding these locations significantly reduced fruit bruising.

Technical Abstract: Modern blueberry packing lines create impact damage to blueberries which will result in fruit bruising. In this study, impacts created by commercial blueberry packing lines were measured quantitatively using a miniature instrumented sphere. Impacts were recorded at transfer points. Average peakG of 66 to 97g, maximum peakG of 230 to 402g, cumulative peakG of 1720 to 2469g and number of impacts of 25.5 to 26.8 were recorded. The highest impact level and largest number of impacts were found when the sensor dropped into clamshell filler or collecting trays. Laboratory tests determined the relationship between the impact level and the bruise rate of the fruit which were useful for accurately estimating the bruise potential of each packing line components. The potential for bruise damage tended to be high at some transfer points where blueberries dropped greater than or equal to 30 cm onto inclined stainless steel surfaces. Padding these locations significantly reduced fruit bruising.