Physics

Soil water

Organic chemistry

Phaseolus

Sorption

Biology

Leaching (pedology)

Adsorption

Engineering

Moisture

Soil science

Chemistry

Geotechnical engineering

Materials science

Water content

Equilibrium moisture content

Dehydration

Botany

Quantum mechanics

Environmental science

Biochemistry

Electric field

Hydration, a crucial preliminary stage of dried bean processing is mostly performed as a slow, batch-wise process. Here we investigated the effect of thermal and pulsed electric field (PEF)-assisted hydration of two common beans (Phaseolus vulgaris) on hydration behaviour, mass loss and leaching of bioactive components. Beans were hydrated in media either using a thermal process (30–80 °C, 10 °C intervals) until equilibrium moisture content (EMC) was reached or were hydrated to 40 g/100 g dry basis moisture at 45 °C, then PEF-treated at an electric field intensity of 4 kV/cm, f = 2 Hz, pulse width 15 μs, pulse numbers from 200 to 1000 (specific energy from 91 kJ/kg to 455 kJ/kg) and further hydrated until EMC. PEF-assisted hydration reached higher equilibrium moisture values and reduced the hydration time by 3-fold for small red beans (1000 pulses, 455 kJ/kg specific energy) compared to 45 °C soak, however, it also leached higher amounts of bioactive polyphenols into the media. Comparable losses of prebiotic oligosaccharides from beans into the media were found in the two hydration approaches. PEF-assisted hydration is a promising alternative to soaking to reduce process time for slow hydrating beans and leaching of bioactive components could be minimised through process optimization.

Thermal and pulsed electric field (PEF) assisted hydration of common beans