Introduction

The object of our inquiry - interactive oscillations of dessicated fruits in aqueous media - is a well known phenomenon, at least in some circles, but has never been thoroughly researched. In our preliminary test, we used 5 types of aqueous media and 5 types of dessicated fruit, to obtain a broad-spectrum view of the limits of the phenomenon.

The Question, as initially proposed, seemed simple - to wit: why does a raisin repeatedly rise and fall when immersed in orange soda? When pondering the broader implications of the question, several possibilities came immediately to mind:

1. It is a property of the raisin
1. A raisin is a fruit
2. A raisin has a high surface area to volume ratio - in other words, a raisin is wrinkled
3. A raisin is relatively non-massive for it's volume
4. A raisin posesses "raisin-ness"
2. It is a property of the orange soda
1. Orange Soda is aqueous
2. Orange Soda is carbonated
3. Orange Soda is translucent
4. Orange Soda is orange

Substances Chosen

Substance I - california raisin - control
Substance II - chocolate-covered raisin - satisfying 1.1 & 1.4
Substance III - children's fruit snack rolled into raisin size & shape - satisfying 1.1 & 1.3
Substance IV - pitted prune - satisfying 1.1, 1.2 & 1.3
Substance V - whole prune - satisfying 1.1 & 1.2

Fluids Chosen

Fluid  - de-ionized water - satisfying 2.1
Fluid  - cold coffee - satisfying 2.1 & 2.3
Fluid  - naturally carbonated spring water - satisfying 2.1, & 2.2
Fluid  - orange soda - control
Fluid  - tap water dyed orange - satisfying 2.1, 2.3 and 2.4

 

Interaction of Dessicated Fruits with Aqueous Media

Substance	Fluid	Fluid	Fluid	Fluid	Fluid
Substance I	sank, bloat	sank, bloat	sank, bubbles, lifted	sank 15 sec, bubbles floated 7 min, sank 30 sec, floated 1 sec, sank, bloat	sank, bloat
Substance II	sank, change color	sank, change color	sank, bubbles, change color	sank, bubbles, change color	sank, change color
Substance III	sank, dissolved	sank, dissolved	sank, bubbles, lifted, dissolved,	sank, bubbles, lifted, dissolved	sank, dissolved
Substance IV	sank, bloat	sank, bloat	sank, bubbles, lifted, bloat	sank 20 min, bubbles, floated 5 min, sank 15 sec, floated - interrupted, sank 6 min, floated 3 min, sank 1 min, floated - interrupted bloat	sank, bloat
Substance V	sank, bloat	sank, bloat	sank, bloat, bubbles, lifted	sank, bloat, bubbles, lifted	sank, bloat

Conclusion

As expected, the control combination (Substance I & Fluid )exhibited the desired oscillation, but unexpectedly, so did the combination of Substance IV and Fluid . In fact, the latter substance proved far more persistent at oscillating than the control combination, after a long initial quiet period.

When we carefully examine the evidence, we see a pattern in that the two substances which evinced oscillation shared these characteristics:

• 1.1 - substance was a fruit
• 1.2 - substance had high surface area to volume ratio (wrinkled)

and
• 1.3 - substance had low mass to volume ratio (light)

Only one aqueous fluid supported the oscillation phenomenon - Fluid ; but Fluid  supported pre-oscillation behavior - 'lifting' from the bottom of the container, but not quite breaking away to rise freely. These fluids shared these characteristics:

• 2.1 - Fluid is aqueous

and
• 2.2 - Fluid is carbonated

Theory

Substance is placed in fluid and, being heavier than fluid, sinks. Fluid contains dissolved carbon dioxide gas which accumulates in wrinkles in fruit's skin until substance plus CO₂ bubbles is lighter than aqueous fluid. Substance rises to surface of fluid where bubbles break, losing CO₂. Substance becomes heavier than fluid, which causes substance to sink, where substance again accumulate bubbles, etc. thus evincing oscillation.

The implications of the revelations explicit in this experiment should be obvious. Further derivations of the inital theorem await further funding from our generous patrons.

Acknowledgements

We would like to thank:

Grant money was supplied by the following organizations:
 

e-mail Dr. Beeker: beeker@flyingmice.com

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