Agriculture Reference
In-Depth Information
rotten cores in apples (Kim and Schatzki, 2000), rind puffing (Njoroge et al., 2002),
and quality determination of pecans (Kotwaliwale et al., 2007). Figure 14.7(g) and
(h) shows monochrome images of rind puffing orange fruits, whereas Figure 14.7(i)
and (j) shows the x-ray images of these fruits when x-ray tube voltage was 50-70
keV. X-ray CT (computed tomography) technology has recently advanced so much
and is expected to have practical use online to detect small size problems such as
moth-sucked point and insect eggs, and young worm in fruit (Ogawa et al., 2005).
14.4.2 N
EAR
I
NFRARED
S
PECTROSCOPY
It has been commonly known that internal qualities of fruits are nondestructively
inspected by NIR spectroscopy such as sugar content, acidity, and rotten core.
Application to fruits of this technology was spread in 1990s as one of the innovative
technologies in this research field. Since the fundamentals and applications of NIR
technologies have been described in many studies (Osborne, 2000; Kawano, 2003),
practical NIR inspection systems for internal qualities of fruits on automation lines
are explained here.
The NIR inspection system depends on the type of fruit. The total transmitting
way is used for small fruits such as orange fruits, kiwi fruits, and waxed apples
with a halogen lamp under the condition of 1 m/s conveyor speed, whereas the
semitransmitting way is for medium-size fruits such as peaches, apples, and pears
with several halogen lamps under the condition of 0.5 m/s conveyor speed. The
semitransmitting light conveys the half bottom information on the internal qual-
ity of fruit when detectors were set under the conveyor lines. Predictable internal
qualities are sugar content, acidity, maturity, moisture content, rotten core, tan-
nin, and so on. Multivariate analysis-based calibration is, however, necessary every
year before starting grading operations for the NIR inspection systems to precisely
predict internal qualities.
14.5 SUMMARY
Many facilities have been developed for grains, fruits, and vegetables. These facilities
are highly automated with sensing devices, and some parts are robotized. Recently, not
only sizes of agricultural products but also internal qualities have been precisely mea-
sured in the grading facilities, in which machine vision and NIR technologies contribute
to informatization of the agricultural products. There are many farming operations:
field management, seedling production, crop management, harvesting, and grading. In
the operations, grading and its preprocessing operations in post-harvesting have a spe-
cial role to add product information and to collect many kinds of information on the
production stage, which can create food safety and security traceability.
REFERENCES
Delwiche, S. R., K. S. McKenzie, and B. D. Webb. 1996. Quality characteristics in rice by
near-infrared reflectance analysis of whole-grain milled samples.
Cereal Chemistry
,
73(2), 257-263.
