Steam-assisted roasting inhibits formation of heterocyclic aromatic amines and alters volatile flavour profile of beef steak

In order to evaluate the effect of steam addition during meat roasting, beef sirloin steaks were cooked at five humidities (0%, 25%, 50%, 75% and 100%) under 230 °C to a centre temperature of 71 °C. With increased humidity, heating rate generally increased and the cooked steak gradually lost the typical roasted appearance. Thiobarbituric acid-reactive substances (TBARS) values generally increased, while carbonyl groups were not affected. Increased humidity promoted the formation of volatile aldehydes and alcohols, while pyrazines decreased significantly from 0% to 25% humidity. Steam-assisted roasting inhibited the formation of heterocyclic aromatic amines (HAAs; except for IQ and Norharman). However, further increase in humidity (larger than 25%) did not have additional inhibition effect. Based on the results, it is recommended to roast beef with steam addition to reduce toxic HAAs, but the humidity should be kept at a relatively low level to maintain a typical roasted appearance and flavour profile.