I think that maybe spicy food isint spicy at all. I mean that the taste is weaker but the tongue just makes the taste stronger. So my question is: Is the spicy food spicy by itself or does our tongue make the taste stronger?

A condition called ‘pine mouth’ is on the rise. It is characterized by an extremely bitter taste in the mouth after eating or drinking. The bitter taste occurs the day after eating pine nuts, and lasts for up to 10 days. It does not happen to all individuals who eat the nuts, and appears to only be from certain batches of pine nuts. It has been suggested that a toxin on the surface of some imported nuts may be responsible. Can anyone provide a plausible biological explanation for this.

Marian Brennan

Newcastle, Wicklow, Ireland

Ginseng oolong tea tastes like ordinary tea (a bit muddy to my palate) until you breathe in through your mouth, and then it feels sweet.  Or at least my sweetness sensors register something.  It's quite a different experience from drinking sweetened tea, which tastes sweet immediately.  Why is this?

Welcome to this Friday's round-up of the week's top questions on The Last Word.

Questions this week have been overwhelmingly biological. Today, we're wondering what is happening to symphylan's tastebuds. When drinking well water after chlorinated water, symphylan experiences a strange bitter taste. Can you explain these tastebud troubles?

For a bit of entomology, Alisong found a 5.5-centimetre-long moth on her gatepost. There's been quite a discussion about it - take a look to find out what it is, or add more heat to the debate.

This one's not for the faint-hearted, but it's pretty egg-citing: take a look at what's hiding in the white of these chickens' eggs.

Ed_Harman was puzzled by his ability to sleep until exactly midday every day, irrespective of the time he goes to bed. Some of our Last Worders help explain why he awakes at the same time every day.

The exception to the biological theme was celliottuk's question: if you want to stop fizzy drinks from going flat, would it help to squash the bottles that contain them?The Last Word members strike again with explanations of what gaseous shenanigans are going on in those bottles.

If you have a better answer for any of this week's questions, roll up your sleeves and get stuck in. Otherwise, sit back and enjoy the explanations!

All the best,

Kat

Letters and comments editor, New Scientist

It's happened a couple of times now that directly after I have a vaccination (the most recent was the rabies vaccine) that I get a slightly acrid taste in my mouth. What causes this?

We're all no doubt familiar with the somewhat metallic taste of blood, but seeing as the tongue has a healthy supply of the stuff, how can it detect it at all?  Surely the tongue should be so used to the presence of blood that any extra should effectively taste of nothing at all?

Most of us will be familiar with the somewhat metallic taste of blood, but how are we able to detect the taste of blood at all, when the tongue already has a healthy supply of the stuff?  Surely with this blood supply adding itself to the taste of everything we, er, taste, then blood itself would effectively taste of nothing?

I live part of the year in an area with chlorinated water, and part of the year in an area with well water. For a few days when switching from chlorinated to well water, the well water tastes bitter. After awhile, the well water tastes delicious. Bottled water also tastes bitter when I've been drinking chlorinated water. What’s going on with my taste buds?

When I have an upset stomach, I sometimes take a strong mixture of baking soda and water. Immediately after drinking this nasty, salty concoction (which works very well, by the way), I drink plain water to wash the taste away. This water invariably tastes extremely sweet, as if it contains sugar. What’s going on with my taste buds?