Jeff Root schreef
What distinguishes fruits which taste fruity from those which
do not?

P van Rijckevorsel replied to Jeff Root:
Mostly sugar? Also color, smell and taste. The substances
responsible for the last two are only very subtly different.

I'm marginally aware of the complex relationship between the
senses of smell and taste, and considered mentioning it in my
first post, but left it out for simplicity. My understanding
is that the sense of taste is limited to sweet, sour, bitter,
and salty, while the sense of smell seems to be unlimited.
So I'm pretty sure that it is really fruity odors that I'm
asking about, when I ask about fruity "taste".

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Actually you are misreading me here. What I said here (very concisely) is
that the chemical substances responsible for smell and taste in a certain
plant are only subtly different from those used by the same plant in
repelling boarders (hey, a pun!). I was assuming you were interested in
chemistry.
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Could you give me examples of:

Fruits which taste fruity but are not cultivated for food.
(And maybe some indication of *why* they aren't.)

98% of all fruits? Laziness?

That seems unlikely.

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Likely has nothing to with it. I am talking Science not Law. Science deals
with observable facts (Law is all about making facts dissappear).
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Everything goes into somebody's mouth at
some time or other, especially when famine hits. If it turns
out to taste any good, someone will try to make money off of it.

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Making money and doing work (or worse: thinking and planning) do not usually
go together. Also, trying is something else than succeeding.
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Fruits which do not taste fruity and are not cultivated for
food. (And again some indication of why they aren't.)

Acorns. Although the fruits are used the trees are not cultivated
for this.

Are you saying that nobody plants oak trees with the intention
of eventually harvesting acorns from them [for food]?

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Surely an eminently safe thing to say?
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The description of "fruit" that I'm using is:

An ovary of a plant, containing the seed or seeds,
together with its envelope and any closely-connected parts.

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This approach is both practical and self-defeating.
If you define as a fruit everything that serves (endo)zoochory (spreading
seeds by including them in something eaten by animals, or the seeds being
designed to be eaten themselves) you are doomed not to get far in finding
examples of plant parts that are fruity without the structure actually being
connected to seeds.
PvR