[morebortplates]

>Ethanol is far more calorie-rich and energy-rich than non-fermented sugars

That's true but there should't be any benefit in terms energy density since the energy content per mass unit in fermented fruit is lower than in unfermented. Yeast uses sugar as an energy source to grow and it converts the sugar into alcohol, CO2 and water as byproducts of its matabolism.

[8note]

If you drop some mass out of the fruit in terms of CO2 and water, the remaining fruit can be more energy dense.

The total mass of the fruit is different

[arrosenberg]

Unless fermentation makes more of the energy accessible for the monkey. Cellulose has high energy content, but humans can’t access it without using heat, acid or microorganisms to break it into something digestible.

[cshokie]

Alcohol does have some calories of its own. I’m unsure to what degree that balances out the reduced sugar, though.

[kencausey]

I think the point is that the fermentation is taking place in an effectively closed system, there is no calorie input. The fermented fruit cannot possibly have any more caloric content than the original fruit, it has just changed form.

[postalrat]

Are you sure? Couldn't the energy be locked away in some form that can't be digested until it's fermented?

[morebortplates]

Exactly. Couldn't have said it better. :)