In order to assess the basic cooking and processing properties of Aquagas-treated food materials, a comparison between Aquagas treatment and boiling and steaming using conventional cooking methods was undertaken using broccoli as a test material. Quality was assessed using physical properties, color, levels of vitamin C and organoleptic criteria and the following results were obtained: 1. Aquagas-treated broccoli scored significantly higher in evaluations of the less watery texture, high degree of sweetness, proper balance of tastes and total score compared to boiled and steamed broccoli, indicating the superior nature of Aquagas food treatment over conventional methods. 2. Physical properties of Aquagas-treated broccoli showed higher values in “skin firmness”, “fracture energy” and “interior firmness.” These results were consistent with total texture scores of the sensory evaluations and meant that Aquagas-treated broccoli was preferred rather than steamed broccoli. 3. Comparisons in color tones between three broccoli samples subjected to different treatments showed significant differences in the green-color indicator-a^* value. The intensity of green color was highest in the boiled broccoli, followed by the Aquagas and steam-treated samples, but no significant differences were observed in sensory evaluations of color and color differences (ΔE^*) among the three samples were minor. Changes in the green color indicator-a^* value in broccoli samples subjected to the three treatments after five days of chilled storage were less noticeable under dark storage conditions compared to illuminated storage conditions. The Aquagas-treated broccoli samples exhibited the smallest change in color. 4. After treatment, the amount of vitamin C remaining in the broccoli samples was 100%, 68%, and 48% for the Aquagas-treated, boiled and steamed broccoli samples, respectively.