Development of white mustard (Sinapis alba L.) essential oil, a food preservative

White mustard essential oil (WMEO) has antimicrobial properties due to the presence of p-hydroxybenzyl isothiocyanate (p-HBITC). WMEO containing about 8% p-HBITC was made on a commercial scale as it is not commercially available. When characterised by HPLC/high resolution mass spectrometry, the triacylglycerols of WMEO and white mustard oil were found to be identical. Non-triacylglycerol components of WMEO could be directly traced back to those occurring naturally in the Brassicaceae family and enhanced by the presence of p-HBITC. New HPLC methods for analysing p-HBITC and its hydrolytic products showed that p-HBITC hydrolysis was slower under acidic conditions. The non-sulphur containing hydrolytic products p-hydroxybenzyl alcohol (p-HBA), p-hydroxybenzyl cyanide (p-HBCN) and p-cresol, were also quantitatively analysed. Commercial production of WMEO containing p-HBITC is feasible and will also result in defatted and deheated mustard flour with about 44% protein as a byproduct.