[Pseudoscience-is-malarkey (OP)]

When taken out of the freezer (the only good way to eat them I think) you have a good five minutes to devour them before becoming soft and boring to eat.

[vhfpmr]

What are candy bars in this context?

Apart from temperature difference, there are three things that determine the rate at which something will thaw out: size, specific heat, & latent heat.

Size.
The amount of energy required to melt something is proportional to its mass which is proportional to volume, but the rate at which heat can enter it via the surface is proportional to the area of that surface. As the size of an object increases the volume increases with the cube of the dimensions, but the surface area only increases with the square, so large objects will have a higher mass to surface area ratio and will therefore take longer to thaw than smaller ones.

Specific Heat.
Is the name for the amount of energy required to raise the temperature of a specified amount of material by a specified temperature: the higher the specific heat the more energy it will take to raise its temperature, and the longer it will take to absorb that energy.

Latent Heat of Liquefaction.
Is the energy required per unit mass to change phase from a solid to a liquid (and LH of vaporisation from liquid to gas), so just like specific heat, the higher this figure is, the longer it will take to absorb enough heat to melt.

Find the mass, surface area, specific heat and latent heat for the ingredients your candy bar is made of, and you'll have the answer to your question.

Perhaps you've noticed that the bars are melting fast compared to ice? Well, the specific heat and latent heat of water are one of the highest of all materials, so if you compare it with other materials it will often be the slowest to thaw.

[alancalverd]

I can't speak from experience of having become soft and boring etc but candy bars contain a lot of sugar and fat so have a lower freezing point and latent heat of solidification than pure ice.

[Bored chemist]

Candy bars typically have melting points at or near 37C.

So they aren't doing any "thawing" when you take them out of the freezer.

Because there's no phase change, there's no need to transfer latent heat.
And with less heat to transfer the transfer is faster.

[alancalverd]

Candy Barr featured in several  gentlemen's entertainment films in the 1970s but they may be considered soft and boring by modern standards.

[paul cotter]

Aha, so you are a connoisseur of such material? Tut tut Alan.

[Pseudoscience-is-malarkey (OP)]

Because there's no phase change, there's no need to transfer latent heat.

If this is true, how do you explain their texture change?

[alancalverd]

Softening of a liquid is not a phase change, just a reduction in viscosity.

[Bored chemist]

Because there's no phase change, there's no need to transfer latent heat.

If this is true, how do you explain their texture change?

Ask a blacksmith.

[Petrochemicals]

Aha, so you are a connoisseur of such material? Tut tut Alan.

Maybe Paul, but it maybe a reference to his star turn as a leading man.

[alancalverd]

Have you come to calibrate my MRI machine?
    Yes, ma'am. What seems to be the problem?
The magnet has ripped all the buttons off my clothes and the escaping helium has made me feel very friendly
    All in a day's work, my dear.
Is that a 3-axis magnetometer or are you just pleased to see me?
    Let's start with your Region Of Interest......

[Director].....ad lib euphemisms and double-entendres, fade to pink and play "Je t'aime" one more bloody time....don't we have any other records, FGS? 

[Petrochemicals]

Have you come to calibrate my MRI machine?
    Yes, ma'am. What seems to be the problem?
The magnet has ripped all the buttons off my clothes and the escaping helium has made me feel very friendly
    All in a day's work, my dear.
Is that a 3-axis magnetometer or are you just pleased to see me?
    Let's start with your Region Of Interest......

[Director].....ad lib euphemisms and double-entendres, fade to pink and play "Je t'aime" one more bloody time....don't we have any other records, FGS? 

I was thinking more "carry on tromboning" with barbera windsor

[Bored chemist]

If "tromboning" isn't a euphemism for something then it probably should be.
If it is a euphemism for something, I can probably live without knowing what.
But in any event, I wonder if a thread about candy is the best place for stuff that's less "family friendly" than most.

[Pseudoscience-is-malarkey (OP)]

Softening of a liquid is not a phase change, just a reduction in viscosity.

I was about to report you to the British Physicist Guild or something for making up a scientific word until I found out it is an actual word.

[Bored chemist]

Softening of a liquid is not a phase change, just a reduction in viscosity.

I was about to report you to the British Physicist Guild or something for making up a scientific word until I found out it is an actual word.

Softening?

[Kryptid]

A word of warning: don't put a Snickers bar in the freezer. I broke a filling that way.