Given a paragraph about cooking, and a set of conversational question answers about the paragraph, generate a relevant question to the topic of the paragraph. The paragraph has the prefix 'CONTEXT:'. Each conversation question has a prefix `Q:` followed by the answer prefix `A:`.

[EX Q]: CONTEXT: Just an idea... I've had problems making foam because of hard/basic tap water (a lot of chalk in the water) - making frape though, not garlic foam:) Foam will more easily form in soft water as you can easily test with a piece of soap. If you have hard tap water you could try using boiled water (some of the chalk in the water will react and leave a residue on the bottom of the pot) or bottled water with pH 7 (neutral). Another idea would be to add just enough acid for neutralisation but I imagine that could be a bit tricky and you'd risk the milk curdling so I wouldn't recommend it.  <sep>  Q: Why was there not enough foam in my garlic foam with soy lecithin? A: Just an idea... I've had problems making foam because of hard/basic tap water (a lot of chalk in the water) - making frape though, not garlic foam  Q: This was my first attempt at making a foam using soy lecithin do you think that will help? A: If you have hard tap water you could try using boiled water (some of the chalk in the water will react and leave a residue on the bottom of the pot) or bottled water with pH 7 (neutral 
[EX A]: I got a bit of foam on top but there wasnt a lot of it. It felt like a waste of a lot of milk. How much foam should I be expecting?

[EX Q]: CONTEXT: Yes, it can go bad.It's pretty much the same as the way flour can go bad: the fats can go rancid. Grains are mostly starch, but they contain enough fat for rancidity to be a noticeable problem. There's a huge amount of variability in how long that takes, though. If it's airtight and kept in a cool, dark place, it'll last much longer than the best before date. But if it's been exposed to air, light, or heat, it can go pretty fast, perhaps even before the best before date.So, smell it. If you detect any unpleasant smells, you probably don't want to eat it. Even if you don't smell anything obvious, it could still be subtly rancid, so if you're planning on serving it to anyone, you might want to cook a small bit to test.  <sep>  Q: Does polenta 'go off'? A: it can go bad  Q: What is an indication that it goes bad? A: If you detect any unpleasant smells, you probably don't want to eat it. Even if you don't smell anything obvious, it could still be subtly rancid  Q: Does the taste change when it goes bad? A: Grains are mostly starch, but they contain enough fat for rancidity to be a noticeable problem 
[EX A]: What else changes when it goes off?

[EX Q]: CONTEXT: I have seen this happening more than once. While I don't know the whole theory behind it, each time it happened, there was something just below the hole, let's call it "the lump". What I think happens is that the lump is too heavy. When the batter below it tries to rise, it doesn't have the strength to push up the lump. This could be combined with differences in heat transfer throughout the batter vs. on the batter-lump transition in preventing rising (I am certain they exist, but I don't know whether they have an effect at all). The result is a hole where the batter didn't rise, surrounded by nicely risen batter. As to where the lump comes from: you say "chocolate and pear cake". If you have pear pieces in the batter, right under the surface, they can do this. I have certainly seen it happen when the recipe includes fruit pieces in the batter. If there are no pear pieces, my second guess is badly dissolved flour. The directions for this type of cake normally include folding the whites very gently, and generally erring on the side of too little whisking. This could contribute to uneven batter texture, resulting in lumps. In the second case, the cake may have some less-than-pleasant pieces, but will still be mostly good. If it is fruit, the holes are purely a cosmetic problem. So not much harm done either way, unless you are shooting for a prize at a baking competition.  <sep>  Q: I baked a cake and it has holes in it why? A: each time it happened, there was something just below the hole, let's call it "the lump  Q: Was it because the batter was uneven? A: What I think happens is that the lump is too heavy  Q: Could it be uneven rising? A: When the batter below it tries to rise, it doesn't have the strength to push up the lump  Q: How could this be prevented? A: folding the whites very gently, and generally erring on the side of too little whisking 
[EX A]:
Anything else?