Articles
ELECTRONIC NOSE-BASED DISCRIMINATION AMONG SPRING ONIONS GROWN ON TWO DIFFERENT SOILS AT THREE WATER-DEFICIT STRESS LEVELS
Article number
600_71
Pages
479 – 484
Language
English
Abstract
Quality
discrimination for spring onions using conventional methods of sensory
appraisal and analytical tests is difficult, expensive and time-consuming.
Discrimination of spring onion characteristics with electronic nose (E-nose)
technology was investigated.
Plants of cv.
White Lisbon were grown in a
glasshouse in pots containing clay (Alluvial gley) or sandy loam (Brown earth).
Irrigation regimes were regular watering to near field capacity (-0.01 MPa soil
water potential, SWP) or re-watering to near field capacity when available
moisture level was depleted to either ≤50% (-0.80 MPa SWP) or ≤25%
(-1.19 MPa SWP). The E-nose sensor response
(%dR/R) was significantly (P<0.01) influenced by irrigation, with %dR/R
decreasing in association with reducing soil water availability.
Effects of
soil type and irrigation regime x soil type interaction for %dR/R were not
significant (P>0.05). Two-dimension Principal Component Analysis (PCA) plots showed significant (D2>3.0)
differences among data set clusters.
Increases in water-deficit level reduced
separations between data set clusters for plants grown on both clay and on
sandy loam.
Regular irrigation increased pyruvic acid concentration by
43% on the clay as compared with 8% increase in mild water-deficit stressed plants
on clay versus severely stressed plants.
In contrast, pyruvic acid
concentration was reduced by 8% in regularly watered plants grown on the sandy
loam as compared with 8% increase in mild water-deficit stressed plants on
sandy loam versus severely stressed plants.
In conclusion, significant (D2>3.0)
separations of data set clusters in association with water-deficit stress but
not soil type were evident on the 2D PCA plots.
However, while the E-nose has demonstrated potential for
discrimination of spring onion quality, further detailed work is required to
characterise the interactions of spring onion volatile components with
conducting polymer sensors.
discrimination for spring onions using conventional methods of sensory
appraisal and analytical tests is difficult, expensive and time-consuming.
Discrimination of spring onion characteristics with electronic nose (E-nose)
technology was investigated.
Plants of cv.
White Lisbon were grown in a
glasshouse in pots containing clay (Alluvial gley) or sandy loam (Brown earth).
Irrigation regimes were regular watering to near field capacity (-0.01 MPa soil
water potential, SWP) or re-watering to near field capacity when available
moisture level was depleted to either ≤50% (-0.80 MPa SWP) or ≤25%
(-1.19 MPa SWP). The E-nose sensor response
(%dR/R) was significantly (P<0.01) influenced by irrigation, with %dR/R
decreasing in association with reducing soil water availability.
Effects of
soil type and irrigation regime x soil type interaction for %dR/R were not
significant (P>0.05). Two-dimension Principal Component Analysis (PCA) plots showed significant (D2>3.0)
differences among data set clusters.
Increases in water-deficit level reduced
separations between data set clusters for plants grown on both clay and on
sandy loam.
Regular irrigation increased pyruvic acid concentration by
43% on the clay as compared with 8% increase in mild water-deficit stressed plants
on clay versus severely stressed plants.
In contrast, pyruvic acid
concentration was reduced by 8% in regularly watered plants grown on the sandy
loam as compared with 8% increase in mild water-deficit stressed plants on
sandy loam versus severely stressed plants.
In conclusion, significant (D2>3.0)
separations of data set clusters in association with water-deficit stress but
not soil type were evident on the 2D PCA plots.
However, while the E-nose has demonstrated potential for
discrimination of spring onion quality, further detailed work is required to
characterise the interactions of spring onion volatile components with
conducting polymer sensors.
Authors
L. Abbey, D.C. Joyce, J. Aked, B. Smith
Keywords
Allium cepa, clay, flavour, headspace volatiles, sandy loam, soil water potential
Online Articles (132)