White pepper vs. black pepper

They don't taste identical at all, and even more important, they don't smell the same. White pepper has a distinct "barnyard" odor. People do indeed use them when black flecks might be unpleasant, but in most cases I'd rather go pepperless or just live with the color.

Same plant for both. Black pepper is unripe fruit (green), picked and sun dried til it turns black. White pepper is the fully ripe seed stripped of its outer husk.

Here's the first link that google gave me to verify. http://en.wikipedia.org/wiki/White_pepper#White_pepper

Also, Harold McGee has a couple of pages in "On Food and Cooking" for further detail.

Black pepper and white pepper are differing preparations of the fruit of the Piper nigrum plant.

Black pepper is made from the unripened, green fruit. It is dried, whereupon the fruit shrivels leaving the distinctive black, wrinkly exterior.

White pepper is the fruit's dried seed without the encapsulating flesh. The flesh is removed by a process called retting, essentially the process of allowing microbes to eat away the tissues surrounding the seed.

The two variants do have a differing flavor as the flesh of the fruit contains terpenes which give pepper much of its scent and flavor. White pepper's flavor can differ depending on how long the retting process was allowed to take place. This may be what produced the off flavors you found.

I found an interesting article by Harold McGee, where he writes that the substance rotundone is contained in much higher concentrations in white pepper than in black, and goes on to note:

...they tested 49 people and found that about 20 percent of them could not detect rotundone at all, even at concentrations far above what’s found in white pepper. The scientists say this shows the different experiences two people can have of the same wine, or of the same pepper-seasoned food.

So the recipe you tried may well have been created by someone far less sensitive to the flavor than yourself and your family. Something worth keeping in mind when seasoning food for a group...

Yes white pepper has a very distinct flavour. Many people perceive it to have a "hotter" flavour, while having less complex flavours than black. If the white pepper flavour seems to dominate a specific dish, I'd simply use less. A lot of recipes call for it simply because of the colour. Personally, I think that's ridiculous as the flavour is very different. I quite like the flavour, but wouldn't add it to everything. If you're trying to find a use for it... find flavours that better compliment the usage of it. It is used in a lot of Cantonese soups and sauces, for example.

I find that the "wetter" the food is when it is served, the more I prefer white pepper. However I prefer black pepper whilst the food is being cooked. Okay, maybe I'm weird but that's what I like. Also, keep ground white pepper in the freezer, it doesn't go solid and lasts ages without getting at all "barnyardy",

I think they taste a little different. It seems to me that black pepper is more spicy when you first eat it and white pepper seems to be more of a lingering spiciness.

When I eat black pepper it numbs my tongue and I cannot taste the food (not only the food that has the pepper, but also anything else I'm eating.) white pepper doesn't do this.

There are substantial differences between the two.

White pepper is produced with ripened pepper, while black pepper is not. White pepper has a more spicy taste, and it might have an odor if it's not well dried because, when producing white pepper, it is kept in water for many days to ease the removal of the outer layer.

Personally, I prefer the taste of white pepper on things like potato chips - and as a benefit, fine white pepper sticks better to the chips, where no matter how fine I grind my black pepper, they do not stick to the chips well enough.

On the flip side, grainy black pepper on top of a well-grilled steak... Just something to die for.

So, my comments address point 3 in your question, as well as the "to taste" element of some of the answers above.