Effects of Temperature and Loading Characteristics on Mechanical and Stress-Relaxation Properties of Sea Buckthorn Berries. Part 1. Compression Tests.

J. Khazaei, Danny D Mann


Force and energy required to rupture the sea buckthorn berry were measured using the
plate test at loading velocities ranging from 0.1 to 4.0 mm/s and ambient temperatures of
4.5, 16.5, 25, and 34.5°C. As berry temperature increased from 4.5 to 34.5°C, the rupture
force decreased 20.7%. There were no significant differences in rupture energy at
temperatures of 16.5, 25, or 34.5°C; but the rupture energy was significantly higher at
4.5°C. Average berry deformation was 1.5 mm and did not vary with temperature.
Consequently, berry firmness decreased as temperature increased. The rupture force and
energy for large berries was significantly higher than that for small berries at 16.5oC,
however, the small berries were firmer. Loading velocity had a significant effect on rupture
force, rupture energy, deformation, and firmness of berries of the Sinensis cultivar, but
there was no effect on berries of the Indian Summer cultivar. For these two cultivars, berry
masses and geometric mean diameters ranged from 0.14 to 0.38 g and from 6.2 to 8.8 mm,
respectively; with the Sinensis berries being more spherical.

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