Due to the above 1 and 2, a high efficient heat transfer is achieved.
Comparison of vitamin C content in vegetables after different heat treatments (Report from Inui et al (Osaka Prefecture University)
| Vitamin C (mg/100gFW) |
 Broccoli |
 Carrot |
 Pumpkin |
|---|---|---|---|
| Boil cooking | 16.7±5.9 | 2.1±0.5 | 7.8±1.3 |
| Superheated steam (our device) |
56.0±3.3 | 2.6±0.3 | 10.0±2.2 |
| Raw | 88.3±1.8 | 4.9±0.7 | 12.7±1.4 |
Comparison of vitamin C content in vegetables after different heat treatments (Report from Inui et al (Osaka Prefecture University)
Broccoli |
16.7±5.9 | 56.0±3.3 | 88.3±1.8 |
Carrot |
2.1±0.5 | 2.6±0.3 | 4.9±0.7 |
Pumpkin |
7.8±1.3 | 10.0±2.2 | 12.7±1.4 |
It is verified that in superheated steam cooking, the retention of VitaminC in broccoli which contains a lot of vitamin C is high (63.4% retained)
| Broccoli | Cabbage | |
|---|---|---|
| Superheated steam (our device) |  Kept the green color |
 Kept the green color |
| Boil cooking |  Partially discolored |
 Discolored (whitish) |
| Broccoli |
Kept the green color |
Partially discolored |
| Cabbage | Kept the green color |
Discolored (whitish) |
It is confirmed that a process of degradation is well controled.
Comparison conducted under a condition of boiling potatoes (pieces of app. 15 g)
| Multi steam cooker | Steam Convection Oven 10-stage gas system by company X | Rotary pot (gas) capacity: 190 L | |
|---|---|---|---|
| Processing ability | 140kg / h | 30kg / h | 45kg / h |
| Electricity usage (electricity expense) |
4kW/h (76JPY/h) | 0.54kW/h (10JPY/h) | ー |
| Water consumption (water expense) |
48L/h (19JPY/h) | 10L/h (4JPY/h) | 225L/h (90JPY/h) |
| Steam consumption (fuel expense) |
110kg/h (737JPY/h) | ー | ー |
| Gas consumption | ー | 35kW/h (280JPY/h) | 50kW/h (400JPY/h) |
| Cost for processing1kg of potatoes | 5.9JPY | 11JPY | 10JPY |
