What do the words bitter and sour mean to you? I’m not sure if it’s a colloquialism or a general UK difference, but as a kid growing up I was told sour is what you get from lemons, for instance, and bitter would come from eating something like a coffee bean. That said, though, I’ve definitely heard people refer to lemons as tasting bitter, which begs the question what does sour mean to them, and if lemons taste bitter, what would a coffee bean taste like?
Whilst I tend to agree with @Earp and @Xoic about sourness of lemons and bitterness of, well, a pint of bitter, bitter lemon is a thing - it is a drink in its own right, and the title of a book by one of the Durrells, Bitter Lemons of Cyprus (great read as an aside); but - here's a thing - the titular bitter lemons refer to the after-taste of the souring of relations between Greece and Turkey (their governments, not the people who were suddenly expected to be at war with their friends and neighbours). TLDR - wondering whether sour can refer to the taste and bitter to the aftertaste. Or do sour flavours tend to have a sweetness that bitter flavours lack?
Sour and bitter are two distinct tastes detected by two different types of cells within taste buds. Sourness detects acidity (hydrogen ions) and bitter detects unpleasant tastes (therefore potentially toxic). Human Biology of Taste
The tongue map has long since been refuted. https://www.smithsonianmag.com/science-nature/neat-and-tidy-map-tastes-tongue-you-learned-school-all-wrong-180963407/
I agree with @Hammer. People sometimes say lemons taste bitter, because bitter lemon does exist. Bitter lemon is sour, but it also has a bitter taste to it, and some lemons have that undercurrent of bitterness, like a grapefruit does. When people say a lemon is bitter, what they really mean is that it tastes bitter *as well as* tasting sour, because the sourness goes without saying. Even if you put sugar into coffee, it will still have a bitter taste to it, in addition to being sweet.
This is all well and good and all, but the real question is—how do you classify the taste of dill pickles? Not exactly bitter or sour. something else maybe? Something we don't even have a name for, aside from 'tastes like dill'? On second thought I guess they're a type of sour. Sort of like sauerkraut.
The flesh and juice of a lemon are sour and acidic, while the rind and pith are bitter and oily. So for me it depends on what part of the lemon you're talking about. Eating a teaspoon of lemon juice or a teaspoon of lemon zest will be quite different experiences .
Coffee, wine, black tea: astringent is the word you'd use for them. They have bitter notes too, but most pronounced is the drying sensation you 'taste' when consuming them.
I haven't touched coffee in more than 40 years, but I regularly drink black tea. Perhaps "astringent" might apply to some red wines. It is not a word I would ever associate with black tea or white wine.
It's always going to be associated with tannins (phenols). So white wine, no—it doesn't have the grape skin characteristics. But red wine, coffee, and black tea for sure. I also need to get this off my chest because I had to listen to a superior get it wrong: you don't get any more caffeine after steeping tea for 5 minutes. It's just more tannins liberated. Doesn't hurt to squeeze the bag when taking it out, though.
Sour, definitely. Use to pick it from neighbour’s garden and eat it raw, dipped in sugar to counter the sourness.
