Investigating factors affecting postharvest splitting in radish (Raphanus sativus)

Splitting of the radish (Raphanus sativus) hypocotyl is a problem for commercial growers as losses due to splitting can reach 30%. High levels of splitting means batches of radish have to be hand sorted which is costly.
Previous experiments have shown the moisture content of the hypocotyl can vary as a result of both pre and post-harvest environment.
It is thought the moisture content and turgidity of the hypocotyl at harvest, and during post-harvest handling, may influence the susceptibility of the hypocotyl to damage.
Hypocotyl moisture content was manipulated by saturating the hypocotyl in de-ionised water or by air drying to achieve a range of moisture contents between 94 and 97%. The hypocotyls were tested for susceptibility to splitting as a result of post-harvest mechanical damage using impact, compression and puncture tests.
Radish hypocotyl moisture content was found to be negatively correlated with puncture force.
Puncture force decreased linearly from 1.1 kg for hypocotyl moisture contents less than 95.5% to 0.7 kg for moisture contents above 97.5%. Additionally failure force due to compression decreased linearly from 26.7 kg for hypocotyl moisture contents above 95.5% to 15.3 kg for hypocotyl moisture contents below 98.5%. No relationship was found between splitting due to impact and hypocotyl moisture content.
These results suggest radishes are more susceptible to splitting post-harvest from compression and puncture at high hypocotyl moisture contents.

XXIX International Horticultural Congress on Horticulture: Sustaining Lives, Livelihoods and Landscapes (IHC2014): International Symposium on Root and Tuber Crops: Sustaining Lives and Livelihoods into the Future

R.A. Lockley, I.G. Grove, J.M. Monaghan

moisture content, hypocotyl, texture analysis, crush, impact, puncture

https://doi.org/10.17660/ActaHortic.2016.1118.25