Six kitchen wastes of raw, acid‐washed, NaCl‐loaded, Na2CO3‐loaded, NaB‐loaded, and Na‐exchanged noodles were torrefied at 300 °C. The six torrefied noodle samples were then gasified in air (equivalence ratio = 0.2) at 600, 800, and 1000 °C, respectively. The results suggest sodium could significantly increase the production of CO and H2. For Na‐exchanged noodles, the yields of CO and H2 at 1000 °C were 0.39 and 0.30 Nm3/kg, respectively, much higher than that of 0.29 and 0.20 Nm3/kg for acid‐washed noodle. Meanwhile, sodium could accelerate the decomposition of liquid, particularly for the polycyclic aromatic hydrocarbons. The catalytic effect of sodium as ion‐exchanged form is stronger than that of sodium in H2O‐soluble form. Among the H2O‐soluble sodium compounds, Na2CO3 shows the best catalytic effect. When torrefied noodle samples were gasified, the amounts of sodium as CH3COONH4‐soluble and H2O‐soluble forms were reduced from 48.4% and 18.3% of torrefied noodle sample to 5.1% and 5.9% of gasified noodle sample at 600 °C, indicating that the CH3COONH4‐soluble sodium had the higher volatility than H2O‐soluble sodium. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.