Why do Lifesavers no longer produce a blue flash, but Altoids still do?

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Discussion Overview

The discussion centers around the phenomenon of triboluminescence observed in wintergreen Lifesavers and Altoids, specifically why Lifesavers no longer produce a blue flash when crushed, while Altoids still do. Participants explore potential chemical changes in the ingredients and the implications of these changes on the observed effect.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant notes that the blue flash in wintergreen Lifesavers is attributed to triboluminescence, where breaking sugar bonds releases UV light that is re-emitted as blue light by methyl salicylate due to fluorescence.
  • Another participant suggests that the use of corn syrup as a sweetener in Lifesavers could be a factor in the absence of the blue flash.
  • It is mentioned that the ingredients of Altoids include both natural and artificial flavoring, while Lifesavers only list artificial flavoring, raising questions about the potential loss of natural wintergreen oil.
  • A participant shares a video demonstrating the flash and provides a sequence of events that leads to the emission of light, indicating that added chemicals could interfere with the fluorescence step.
  • One participant expresses excitement about the potential engineering applications of triboluminescence for detecting friction and material stress.
  • Another participant proposes using a UV camera to investigate whether Lifesavers still emit UV light when crushed, questioning if the loss of the visible flash is complete or just a change in fluorescence.
  • A participant reflects on their experiences with the wintergreen blue flash and expresses concern about the changes, while also acknowledging the potential for dental issues with attempts to recreate the effect.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the reasons behind the change in Lifesavers, with multiple competing hypotheses regarding the ingredients and their effects on triboluminescence remaining unresolved.

Contextual Notes

The discussion highlights uncertainties regarding the chemical interactions involved in triboluminescence and the specific contributions of different ingredients in the candies, which are not fully explored or resolved.

Ivan Seeking
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Most nerds know that if you crunch a wintergreen lifesaver in your mouth or with a pair of pliers, it flashes blue light due to triboluminescence, . Breaking the bonds in the sugar molecules releases UV, which is then re-emitted as blue light by the wintogreen flavoring [ Methyl salicylate ] due to fluorescence. It has long been a fun, favorite science demo for kids.

Recently I mentioned this to a young engineer at work who immediately had to try it. But she said it didn't work! WHAT? So I picked up an identical product which also did not produce a flash. But Wintergreen Altoids do flash.

I am wondering if the use of corn syrup as a sweetener could be the problem. I haven't dug into the chemistry but it struck me as a suspect when I read the ingredients label. Also, the Altoids, which do still flash, list natural and artificial flavoring. The Lifesavers only list artificial flavoring. So I wonder if they stopped using natural wintergreen oil. in any event, I thought it would be fun to figure out what has changed. l

It is too bad that this fun demo seems to be going away.
 
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@Borek may have an answer. Calling @Borek you’re wanted in the candy aisle.
 
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Nah, we don't have these here so I am clueless.
 
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Can we send you some for evaluation?
 
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Here is a nice video of the flash, with explanation.

Here is one with more general explanation, not as good pix.

It seems it goes:
break crystal --> separate charges --> get spark --> UV photon --> make fluorescence with neighboring molecules

Added chemicals can interfere with the fluorescent step (can be a problem with fluorescent microscopy).
I don't know about the other steps.
 
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BillTre said:
Here is one with more general explanation, not as good pix.

OMG I am all excited now. Triboluminescence has sparked my imagination! :D As the man says, this might be used as an engineering tool for the detection of friction, stress/strain, and fracturing, in a wide range of materials. I can easily imagine using this knowledge for what I do.
 
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PS, if anyone has a UV camera, maybe you could try this with lifesavers and see if you get a UV flash when you crush one. Have we lost the UV flash completely or just the fluorescence in the visible range?
 
Perhaps it would be easier to see if they fluoresce under UV

I have amazed and bemused countless folks of all ages with the Wint-o-green blue flash. I would be more upset by the change but at my age any attempts to produce the flash could well invite dental repair. So it goes. Very interesting though.
 
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