P van Rijckevorsel replied to Jeff Root:

What distinguishes fruits which taste fruity from those which
do not?

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".

I strongly doubt that sugar (sweet) is the main determinant of
whether something tastes fruity. This is an assertion I've seen
before, though, and I don't understand why.

Adding sugar to tomatoes, cucumbers, or squash doesn't make
them taste fruity. I've had many fruits that tasted fruity
without tasting sweet (although I have no idea of the actual
sugar content), and fruits which normally taste fruity which
had noticeable natural sweetness but equally noticeable lack
of their normal fruity taste.

Color is surely irrelevant.

For example, apples, oranges, bananas, strawberries,
and grapes usually taste fruity when ripe, while bell peppers,
tomatoes, cucumbers, okra, olives, and squash generally do not.
(When anyone other than a botanist mentions "fruit", what is
meant is almost always a member of the first group, and not
the second.)
Could you give me examples of:

Parts of plants which taste fruity, but are not fruits.
(The only example I can think of is rhubarb.)

cashew (not the nut), juniperberry, yew berry, etc

I never heard of the cashew "fruit" before, and a search turned
up only a single web page which tells about it. It appears that
the cashew fruit is part of a strategy by the cashew tree to get
animals to eat the tasty flower stalk and throw away the nut
encased in its hard shell protected by caustic oil.

Juniper berries sound familiar, but it is a long time since I
last looked at a juniper plant up close. Without a photo, it
is hard to imagine how a cone can look like a berry. Apparently
the berry is used mainly for its fragrance in cosmetics, but is
also sometimes used as a spice. As far as I can tell, the
juniper berry serves the same purpose as a fruit, so I would
think that the most reasonable way to classify it would be to
say that it *is* a fruit. Like birds have wings, and bats have
wings-- they're both wings even if they evolved independantly.

This description was given of juniper berry oil: "It's pungent,
herbaceous, pepery odor is pine-like and comphoric." Since they
misspelled "peppery", I'm guessing that "comphoric" should have
been "camphoric". That doesn't sound exactly "fruity", but may
be somewhat close.

The only info I found on yew berries is that the fleshy covering
of the berry is the only part of the tree that isn't poisonous.

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. 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.

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?

Could you give me examples of:
Parts of plants which taste fruity, but are not fruits.
(The only example I can think of is rhubarb.)

cashew (not the nut), juniperberry, yew berry, etc

And, strictly speaking: apples and pears, strawberries and
raspberries, figs, etc

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.

Although I'm asking these questions in a botany newsgroup, I'm
writing mainly for people who are familiar with fruits they find
in grocery stores, and will likely never go far beyond that.
If it looks like a fruit, smells like a fruit, tastes like a
fruit, and is in the fruit section of the produce department,
they will say that it probably *is* a fruit.

Thank you! This is more work than I wanted, but progress!

-- Jeff, in Minneapolis

Subtract 1 from my e-mail address above for my real address.
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