Paper · 2020 · HortScience

Nondestructive Determination of Fruit Surface Area Using Archimedean Buoyancy

Grecia Hurtado; Patrick Lüdeke; Moritz Knoche

12
claims
12
verbatim quotes
2
citations
2
research areas
✓
Open access · cc-by-nc-nd

Abstract

Estimates of fruit surface area are often required in physiological and technological studies. The objective was to establish a procedure to accurately quantify the fruit surface area based on Archimedean buoyancy measurements. The setup comprised a fixed, linear stepper motor mounted with its spindle vertical and aligned directly above the pan of an electronic balance. A fruit was clamped to the motor spindle and a beaker of water rested on the balance pan. When the motor was activated, the fruit was progressively immersed, stepwise, in the water. Each vertical displacement step increased the buoyant upthrust on the fruit, which was opposed by a corresponding increase in the downthrust on the balance. Pairs of the step displacement length (mm) and corresponding buoyancy increment (g) values were recorded in an MS Excel (Microsoft, Redmond, WA) spreadsheet using Arduino components. Each displacement step immersed another “virtual slice” of the fruit in the water. From each pair of known displacement–buoyancy measurements, the volume (mL) of that slice could be calculated with high precision based on the known density of the liquid (g·mL −1 ). With the fruit orientated so that its morphological “long” axis was vertical, for most fruitcrop species, the slice can be assumed to have a circular cross-section. Hence, the slice can be analyzed geometrically as a truncated cone of known height (mm) and known volume (mL). Therefore, the surface area of its outer face is calculable. The surface area of the whole fruit was calculated as the cumulative total of the surface areas of all steps (virtual slices). The procedure was evaluated and calibrated using stainless-steel spheres in place of the fruit. However, the measured surface area was slightly greater than that calculated for a sphere. The calculated and measured areas did not differ by more than 1.7%. The surface area determinations were highly reproducible ( cv = 0.95%). The magnitude of the displacement steps affected the variability of the surface area measurements. Increasing the step displacements decreased the measurement variability, but there were no significant effects on the surface area measurements of the surface tension of the liquid or of the wettability of the surface of the fruit or the stainless-steel subject. Using stainless-steel spheres (diameter, 5–60 mm) or rubber truncated cones (mean diameter, 8–45 mm) revealed an excellent agreement between the measured and calculated surface areas. Using tomatoes, grapes, blueberries, and strawberries, the measured surface areas were in excellent agreement with those calculated from the fruit dimensions and appropriate geometrical assumptions. The results demonstrate that the surface areas of fruit with approximately circular cross-sections normal to their morphological axes can be determined with high accuracy and reproducibility using Archimedean buoyancy.

Abstract from the paper’s OpenAlex record; open copy licensed cc-by-nc-nd. Read at the source ↗

The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.

Claims 12

Method / resourceobservedoriginal resultmeasured

Claim · model-written summary

Measured sphere surface area was slightly greater than calculated area.

Outcome
measured surface areae0
Direction
slightly greatere0
Comparator
that calculated for a spheree0

Not reportedTaxon

Verbatim

e0

“the measured surface area was slightly greater than that calculated for a sphere.”

✓ located verbatim in the source · abstract, characters 1730–1811 · show in text ↑
Method / resourceobservedoriginal resultmeasured

Claim · model-written summary

Measured and calculated sphere areas differed by at most 1.7%.

Outcome
calculated and measured arease0
Direction
did not differ by more thane0
Value
1.7%e0

Not reportedTaxon

Verbatim

e0

“The calculated and measured areas did not differ by more than 1.7%.”

✓ located verbatim in the source · abstract, characters 1812–1879 · show in text ↑
Method / resourceobservedoriginal resultmeasured

Claim · model-written summary

Fruit surface area measurements were highly reproducible with cv 0.95%.

Outcome
surface area determinationse0
Value
cv = 0.95%e0

Not reportedTaxon

Verbatim

e0

“The surface area determinations were highly reproducible ( cv = 0.95%).”

✓ located verbatim in the source · abstract, characters 1880–1951 · show in text ↑
Method / resourceobservedoriginal resultmeasured

Claim · model-written summary

Increasing displacement steps decreased measurement variability.

Treatment
Increasing the step displacementse0
Outcome
measurement variabilitye0
Direction
decreasede0

Not reportedTaxonComparator

Verbatim

e0

“Increasing the step displacements decreased the measurement variability”

✓ located verbatim in the source · abstract, characters 2051–2122 · show in text ↑
Method / resourceobservedoriginal resultnot significant (as stated)measured

Claim · model-written summary

Liquid surface tension did not significantly affect surface area measurements.

Treatment
surface tension of the liquide0
Outcome
surface area measurementse0
Direction
no significant effectse0

Not reportedTaxonComparator

Verbatim

e0

“there were no significant effects on the surface area measurements of the surface tension of the liquid”

✓ located verbatim in the source · abstract, characters 2128–2231 · show in text ↑
Method / resourceobservedoriginal resultnot significant (as stated)measured

Claim · model-written summary

Subject wettability did not significantly affect surface area measurements.

Treatment
wettability of the surface of the fruit or the stainless-steel subjecte0
Outcome
surface area measurementse0
Direction
no significant effectse0

Not reportedTaxonComparator

Verbatim

e0

“there were no significant effects on the surface area measurements of the surface tension of the liquid or of the wettability of the surface of the fruit or the stainless-steel subject.”

✓ located verbatim in the source · abstract, characters 2128–2313 · show in text ↑
Method / resourceobservedoriginal resultmeasured

Claim · model-written summary

Measured and calculated surface areas agreed excellently for stainless-steel spheres.

Outcome
measured and calculated surface arease0
Qualifier
excellent agreemente0
Comparator
stainless-steel spherese0

Not reportedTaxon

Verbatim

e0

“Using stainless-steel spheres (diameter, 5–60 mm) or rubber truncated cones (mean diameter, 8–45 mm) revealed an excellent agreement between the measured and calculated surface areas.”

✓ located verbatim in the source · abstract, characters 2314–2497 · show in text ↑
Method / resourceobservedoriginal resultmeasured

Claim · model-written summary

Measured and calculated surface areas agreed excellently for rubber truncated cones.

Outcome
measured and calculated surface arease0
Qualifier
excellent agreemente0
Comparator
rubber truncated conese0

Not reportedTaxon

Verbatim

e0

“Using stainless-steel spheres (diameter, 5–60 mm) or rubber truncated cones (mean diameter, 8–45 mm) revealed an excellent agreement between the measured and calculated surface areas.”

✓ located verbatim in the source · abstract, characters 2314–2497 · show in text ↑
Method / resourceobservedoriginal resultmeasured

Claim · model-written summary

Measured tomato surface areas agreed excellently with geometric estimates.

Outcome
measured surface arease0
Comparator
those calculated from the fruit dimensions and appropriate geometrical assumptionse0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Solanum lycopersicum
Solanum lycopersicum · TaxonKod B · CC BY-SA 4.0 · Wikimedia Commons ↗

Verbatim

e0

“Using tomatoes, grapes, blueberries, and strawberries, the measured surface areas were in excellent agreement with those calculated from the fruit dimensions and appropriate geometrical assumptions.”

✓ located verbatim in the source · abstract, characters 2498–2696 · show in text ↑
Method / resourceobservedoriginal resultmeasured

Claim · model-written summary

Measured grape surface areas agreed excellently with geometric estimates.

Taxon
grapese0
Outcome
measured surface arease0
Comparator
those calculated from the fruit dimensions and appropriate geometrical assumptionse0

Verbatim

e0

“Using tomatoes, grapes, blueberries, and strawberries, the measured surface areas were in excellent agreement with those calculated from the fruit dimensions and appropriate geometrical assumptions.”

✓ located verbatim in the source · abstract, characters 2498–2696 · show in text ↑
Method / resourceobservedoriginal resultmeasured

Claim · model-written summary

Measured blueberry surface areas agreed excellently with geometric estimates.

Taxon
blueberriese0
Outcome
measured surface arease0
Comparator
those calculated from the fruit dimensions and appropriate geometrical assumptionse0

Verbatim

e0

“Using tomatoes, grapes, blueberries, and strawberries, the measured surface areas were in excellent agreement with those calculated from the fruit dimensions and appropriate geometrical assumptions.”

✓ located verbatim in the source · abstract, characters 2498–2696 · show in text ↑
Method / resourceobservedoriginal resultmeasured

Claim · model-written summary

Measured strawberry surface areas agreed excellently with geometric estimates.

Taxon
strawberriesFragaria ×ananassae0
Outcome
measured surface arease0
Comparator
those calculated from the fruit dimensions and appropriate geometrical assumptionse0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Fragaria x ananassa
Fragaria ×ananassa · TaxonIvar Leidus · CC BY-SA 4.0 · Wikimedia Commons ↗

Verbatim

e0

“Using tomatoes, grapes, blueberries, and strawberries, the measured surface areas were in excellent agreement with those calculated from the fruit dimensions and appropriate geometrical assumptions.”

✓ located verbatim in the source · abstract, characters 2498–2696 · show in text ↑