Given the background description of some cooking related query, summarize the question into a title

[EX Q]: When looking for a blowtorch for the kitchen, you can buy some reasonably expensive tools. When looking for a blowtorch for plumbing, you can buy some reasonably cheap tools.The price is different. The look is different. The principle is the same. I guess the gas is the same.Why pay more? Is there a health issue? Is the kitchen blowtorch more precise?
[EX A]: Blowtorch - hardware store vs kitchen store. Is there a difference?

[EX Q]: I'd like to experiment with making purées (particularly carrot and parsnip, if it matters), but I don't have a food processor or any other mechanical mixing/blending tool. Is there anything I can do or is a processor necessary?
[EX A]: Can you purée without a food processor?

[EX Q]: I recently bought something that was labelled at the grocery store as a "purple sweet potato". They were larger than what I am used to for sweet potatoes, but looked similar, although they had a purple skin on the outside and white flesh on the inside. I figured since they were labelled as "sweet potatoes", I would prepare them the same way I like to prepare regular sweet potatoes, by boiling them first (for about 40 minutes), then removing the skin, slicing it into wedges and then pan frying them. I have done this many times with normal sweet potatoes, and it works quite well.However, after I boiled the purple sweet potatoes for 45 minutes, I pulled them out to take the skins off, and they were soft and stringy and incredibly off putting - they felt the same way as a gummy mashed potato would feel, and they fell apart all over the place.Are they more like a potato, requiring less boiling time? Or is there something else going on here that I am missing?Edit: I went to the grocery store today, and they are now labelled as "purple yams". I don't know if that makes a difference or not. I also got a picture of them, to make my description a bit clearer.
[EX A]:
Cooking "purple sweet potatoes" or "purple yams"