Thermal inactivation of myrosinase in yellow mustard seed

Yellow mustard seed use has been limited because of the pungent flavor the enzyme myrosinase produces. Complete inactivation of myrosinase could increase use. A continuous pilot-scale process for the thermal inactivation of myrosinase was developed and evaluated. The process consisted of a steam-jacketed screw conveyor for preheating followed by a steam-injection system. Three steam-line pressures, ranging from 101 to 240 kPa, and six seed flow rates, ranging from 300 to 800 g/min, were evaluated. The residence time distribution was characterized, using colored tracer at three different seed flow rates. A steam line pressure of 140 kPa and a mean residence time of 12.8 min appeared to achieve complete inactivation of myrosinase. The flow behavior was a combination of plug flow and perfect mixed flow.