Fun with Grapes - A Case Study

Last Updated: 14 June 1994


Patrick R. Michaud,


Using only cheap, readily-available equipment, you can create a spectacular lightshow in the comfort of your very own kitchen, providing hours of fun and excitement for your family, friends, and pets!

Ordinary grapes, when properly prepared and microwaved, spark impressively in an extremely entertaining manner.


We have made an important new discovery in the field of culinary entertainment. Properly prepared, the common seedless grape can be made to combust spectacularly when subjected to a short (5-10 second) duration of microwaves. This study was conducted based upon suggestions from dozens of IRC #root participants using locally available funds and equipment.

Materials Required

The following materials were needed for this study:


  1. The authors carefully cleared the laboratories of all non-essential personnel, especially those persons who might attempt to abort the experiment while the grapes were still in the pre-combustion phase.
  2. Next, the grapes were carefully prepared for proper theatrical effect. The knife was used to carefully slice the grape almost in half, leaving the grape halves attached by the skin. Next, the grapes halves were placed face down in the middle of the microwave safe plate (Figure 1).

    Figure 1. Grape prepared for theatrical effect

  3. Next, the plate with the prepared grapes were placed into the center of the microwave oven and the door carefully shut. The microwave was set to cook at full power for 40 seconds. Finally, after the various recording devices were in place, the start button on the microwave was engaged.

Observed Results

As can be seen from figure 2, the effect of the microwaves on the sliced grapes produced an extremely satisfying flare and associated sparks. The photographic quality of figure 2 is slightly deteriorated due to the poor lighting conditions at the time of the experiment.

Figure 2. Theatrical effect

The sparks began approximately 5 seconds after the microwave was started. Approximately 3-4 seconds after that, the force of the sparks separated the grape halves by approximately 1.5 cm, ending the theatrical effects. At that point the microwave session was aborted to prevent further damage to the microwave and/or grape. The post-combusted grape is shown in figure 3.

Figure 3. Post-theatrics grape.

Discussion and Conclusions

As this report was being prepared, it became evident to the researchers that a mis-communication occurred from the experimental design to the actual conduct of the experiment. The original experimental design called for the grapes to be placed on the plate with the sliced side up, whereas this experiment occurred with the sliced sides placed downward. Further research will be required to determine if the positioning of the grapes significantly affects the theatrical results.

A future experiment calls for the microwaving of multiple grapes simultaneously for increased theatrical effect. For those who wish to forge ahead on this research, the authors suggest separating each grape by a distance of 1.5 cm or more. Note that the authors take no responsibility for any accidents resulting from mis-application of this study. If your microwave blows up and your house catches fire, call the fire department, not us. Our microwave ovens appear to be in good shape after repeated experiments.

The results of this study will greatly enhance the field of culinary entertainment. New pyrotechnic methods have been developed using commonly available grapes and microwave ovens. The results of this study and its derivative works provide fertile ground for new research. The authors are planning to use this research as a basis for experimentation with other species of grape and produce. Results of such study will be made available in future publications.


The authors gratefully acknowledge the operators of IRC and the participants of channel #root, without whom this study would have been left incomplete.

Patrick R. Michaud/