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ARS Home » Northeast Area » Kearneysville, West Virginia » Appalachian Fruit Research Laboratory » Innovative Fruit Production, Improvement, and Protection » Research » Publications at this Location » Publication #319460
Title: Blueberries for fresh market and measure of mechanical impacts in commercial blueberry packing lines and mechanical harvesters and potential damage to blueberry fruit

Author
item Takeda, Fumiomi
item LI, CHANGYING - University Of Georgia

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/11/2015
Publication Date: 8/14/2015
Citation: Takeda, F., Li, C. 2015. Blueberries for fresh market and measure of mechanical impacts in commercial blueberry packing lines and mechanical harvesters and potential damage to blueberry fruit [abstract]. Second Chilean Congress on Berries. p. 13-15.

Interpretive Summary:

Technical Abstract: In the United States of America (USA), fresh blueberries are now available all year round because of significant amount of shipment of fresh blueberries during winter months from Chile and several other countries in South America. Blueberry fruit is susceptible to bruising from mechanical impact. Bruised fruit has shorter postharvest shelf life and softens rapidly in cold storage than non-bruised fruit. A blueberry packing line consists of a hopper for transferring fruit in field containers onto a conveyor line that moves fruit into trash removal equipment, electronic sorter, inspection line, and finally onto clamshell-filling equipment. Blueberry fruit drops as it is transferred from one equipment to the next on the packing line. The mechanical impacts that occur on blueberry packing line equipment were measured quantitatively with a miniature, instrumented sphere called the blueberry impact recording device (Fig.1). BIRD I and II were used to evaluate 11 packing houses in Florida, Georgia, North Carolina, and Michigan in 2013 and 2014 and eight packing lines in Chile (Linares, Cauquenes, Parral, and Chillán). The BIRD II sensor recorded impacts at transfer points or wherever there was a vertical drop on the packing line (Fig. 2). The potential for impact damage was determined in 'Farthing', 'O'Neal', 'Reveille' and 'Star' in North Carolina and ‘Legacy’ in Chile by dropping fruit from different heights. The measured data revealed that the largest impacts (approximately 230 g) were recorded when the sensor dropped into the hopper above the clamshell filler on eight empty lines. When the transfer points were padded with Poron foam sheet, significantly lower levels of impact were recorded by the sensor. The severity of bruise damage resulting from fruit being dropped was related to the impact data recorded by the BIRD sensors. Using peakG-velocity change plot and the fruit bruising rate, several large impacts sufficient to cause bruising were identified (e.g. greater than 25 percent of cut surface area indicating bruise damage) (e.g. in 76 percent of 'Reveille' fruit). The research quantitatively measured the mechanical impact on blueberry packing lines for the first time and the information will assist in improving the design and configuration of blueberry packing line equipment. These changes should result in reducing the magnitude and frequency of mechanical impacts and bruise damage in blueberry fruit. In the USA, the harvesting of blueberries for fresh market is done with over-the-row machines although mechanical harvesters cause bruise damage to the fruit. The BIRD I sensor measured the quantity and magnitude of mechanical impacts created by three major types of commercial blueberry mechanical harvesters (rotary, slapper, and sway). The data collected by the sensor revealed that the slapper and sway harvesters generated not only larger number but also higher magnitude impacts than the rotary. Our analyses suggested that these disparities were mostly caused by different agitating mechanisms, contacting surface materials, and designs between the three harvesters. Results indicated that most impacts lasted 5–7 ms in all three harvesters. The distribution of the impacts showed that 90 percent of impacts from the rotary were less than 190 g and 90 percent of impacts from the slapper and sway were less than 250 g. The highest impacts occurred when the sensor contacted the catcher plate. Corresponding measures were identified to reduce potential bruise damage in the harvesters. The information is useful to selecting harvesters that create the least impacts and to improve current mechanical harvester designs. See attached document with figures.