Inhibition of potato tuber sprouting during storage by the controlled release of essential oil using a wick application method

A method is described whereby the effect of some essential oils on potato sprout growth was investigated. The essential oils were applied by wick volatilization to assess both cumulative release and release rate of each oil. Sprout suppression was assessed on the basis of sprout length at 14 and 28 days after applications. The mechanism of the volatile oil release was a first order kinetic action and the release profile demonstrates a diffusion-based delivery system. The oils evaporated rapidly during the first three days, reaching 45%, 39%, 42%, 32% and 30% for Monodora myristica, Cymbopogon citratus, Chenopodium ambrosioides, Lippia multiflora and Zingiber officinale, respectively. Thereafter the evaporation rate was relatively constant. Tubers treated with L multiflora and C. citratus had shorter sprout at 14 days with sprout length of 4.00 mm and 4.56 mm, respectively, when compared to tubers treated with the other volatile oils and control. At 28 days Z. officinale appeared to have the greatest sprout suppression activity with sprout length of 5.65 mm. The formulated essential oils are suitable for application as sprout suppressants. The responses were concentration and time dependent. The wick method reduced the volatility of the essential oils and extended the sprout-free period of stored potatoes. (C) 2012 Elsevier B.V. All rights reserved..