Hi-Tech Camera "Tastes" Apples to Ensure
Quality By Don
August 7, 2002
Wouldn't it be nice to check an apple's taste before buying it,
without chomping down? You surely wouldn't want an inspector pre-tasting the
apple you buy, but how about a robot?
The robotic inspection cameras envisioned by
Agricultural Research Service scientist
Renfu Lu would "taste" every single apple by bouncing light off it to sense
sugar content and firmness, the top two things that make an apple taste
Lu has developed mathematical equations that relate sugar
content to the amount of light absorbed by an apple, and firmness to the amount
of light bounced off the apple. Lu is an agricultural engineer at the ARS
Sugarbeet and Bean Research Unit in East Lansing, Mich., the third largest U.S.
Washington State produces almost half the nation's apples--and
is partially funding Lu's work--while New York and Michigan together produce
another 20 percent. Lu's research is critical to these and all apple-producing
Apple packinghouses currently rely on digital camera imagery to
sort apples by surface appearance only, flagging those that are visibly
defective or the wrong size or color. The current system can't detect bruises
beneath the skin--or flavor and other internal qualities.
Lu looks deeper by adding lights and spectroscopy to analyze
various wavelengths of reflected light. When the system is fully developed,
specially designed software will allow a computer to sort apples by the
internal quality attributes--firmness, ripeness and taste--required for various
Lu's digital imagery system can easily be merged with those in
packinghouses and adapted to other fruits such as peaches and pears. He is
currently working with cherries as well as apples.
More information on robotic inspection for taste in apples can
be found in the August
2002 issue of Agricultural Research magazine.
ARS is the U.S. Department of
Agriculture's chief scientific research agency.