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A couple weeks ago, I put a plate of food with a dish containing curry and lamb outside in the cold (my refrigerator was broken, and I know that this was an unsafe practice; I will not be asking for any professional advice based on this fact, just a scientific query about fat residue). Shortly after, the food was exposed to the elements: sun, rain, and a raccoon. Recently, I took the food back inside, dumped all the expired contents, and washed it immediately in hot water and dish soap. Much to my surprise, there was a layer of fat residue on part of the inner side of the plate that would not come off! I tried scrubbing it with different kinds of soap, running it through both hot and cold water again, scrubbing it with my fingers, but to no avail. My fingers merely left print marks on the fat as I was scrubbing it, and when I smelled it, it still had the faint odour of freshly cooked lamb. The fat was white with a yellowish tint, very thick, and may have reduced the friction coefficient on my hands after I washed them (although I'm not entirely sure about this one).
I have two questions:
1) What possibly could have caused the lamb fat to procure an industrial-strength durability?! I do not recall the plate being this hard to wash right after putting the lamb dish in it, if I had tried transferring it to another plate and washing the first one.
2) What chemical or technique can I use to remove the fat from the edge of the plate? Am I better off throwing out the whole plate? (I'm playing it safe here, and assuming that the plate is only safe when all surfaces are disinfected by heat, without residue of any kind that could harbour pathogens -- again, I'm not asking for any professional advice related to this, medical or otherwise).
Thanks. (I live in Canada, where the temperature at night can easily drop below -10C Centigrade).
I don't know about the first question. I could speculate, but I'll leave that for others.
Soap can be used to remove fat because it works as an emulsifier. If that's not good enough, you can try a stronger base, like ammonia solution or even sodium hydroxide solution. Bases act on the fat by breaking it down into glycerol and fatty acids, which tends to be rather effective. But bases have a tendency to dissolve aluminium, so if you're dealing with an aluminium plate, better try something else. PiusImpavidus (talk) 09:25, 26 February 2020 (UTC)[reply]
I'd suggest (a) scraping off as much of the fat as possible with a thin knife blade followed by (b) re-heating the plate to liquify the residue before recleaning it with hot water and soap/detergent. You don't mention the composition of the plate, but if it's conventional glazed porcelain without cracks or pores it shouldn't have actually absorbed any of the fat – that's why tableware is made from porcelain. {The poster formerly known as 87.81.230.195} 90.202.162.227 (talk) 13:47, 26 February 2020 (UTC)[reply]
I would suggest NOT to heat a ceramic plate by conventional means, lest the OP wants to explore the wonderful world of thermal shock and fracture mechanics. Same advice for plastic (because of the absolute temperature rather than the gradient though). Maybe microwaving could work in heating the residue rather than the plate, but whether it will be enough to make it come loose is another question. TigraanClick here to contact me 17:04, 27 February 2020 (UTC)[reply]
If the plate is plastic, I would not rule out some kind of weird chemical reaction between the decomposing fat and plastic itself. --Jayron32 12:59, 27 February 2020 (UTC)[reply]
I usually wipe fat like that off with a paper towel, it seems to get almost all of it off, then wash in hot water and detergent.49.197.54.240 (talk) 05:51, 28 February 2020 (UTC)[reply]
Can anyone recommend me some not too hard to read, Brian Greene type books about chemistry? I was reading Feynman's Lectures on Physics and was intrigued by the description in the introduction of how chemistry uses macroscopic methods (colors of substances etc.) to understand in an "unexpected" way the microscopic structure of a compound, and I'd like to learn a little more about that. Thanks! 95.168.116.25 (talk) 18:39, 26 February 2020 (UTC)[reply]
Our Category:Science communicators sadly isn't disaggregated by branch of science. Category:Popular science books is, but from a cursory glance, has nothing about chemistry. So, for now, and pending a better answer (I feel like this Q deserves one), take a look at this list on GoodReads. Aecho6Ee (talk) 19:14, 29 February 2020 (UTC)[reply]
Thanks, I've borrowed Uncle Tungsten, might not be what I was going for but I'm a big fan of Sacks so it's so far an entertaining read anyway! 93.136.1.34 (talk) 20:47, 2 March 2020 (UTC)[reply]
looking for CPSS or CSS info (UPS-style device) and interlanguage wikilink[edit]
What kind of geological processes have led to Java Sea's current shape? I've just noticed it seems oddly rectangular. 89.172.8.50 (talk) 23:51, 26 February 2020 (UTC)[reply]
Find the rectangle
The tectonics of Indonesia is very complex, and the processes that gave rise to this specific shape are probably best described in terms of randomness. (Explain why Italy is a high lady boot kicking a deflated football named Sicily.) Contributing factors are also the desire of hydrographers to assign neat boundaries to somewhat arbitrary partitions, and our bias to seeing patterns and familiar shapes that have no objective existence. When viewing this on a blind map, the alleged rectangularity is not particularly striking. --Lambiam 09:05, 27 February 2020 (UTC)[reply]
What do tectonics have to do with the Java Sea? It's relatively recent, formed by the submerging of a limestone plateau at the end of the last Ice Age. The shape, and its simplicity, is largely random, but also a combination of some coasts which are lacking in large estaurine features, together with large sea boundaries which are simply drawn as straight lines, and mostly perpendicular to the coasts. Andy Dingley (talk) 19:47, 27 February 2020 (UTC)[reply]
Lambiam is onto it. Our brains tend to try to make sense of random things, and sometimes sees things that just happen to remind us of something. The Man in the Moon is an obvious example. ←Baseball BugsWhat's up, Doc?carrots→ 20:11, 27 February 2020 (UTC)[reply]
Sorry, I should've added the picture. It's more obvious in this picture on the right or the one here: Indonesia#Administrative_divisions. Look at the coasts of Lampung, Banten and West Java province for the best match. The right side of the quadrangle in the Java Sea picture requires drawing two imaginary lines from Celebes but the other three sides seem fairly obvious to me. My first thought was also tectonics, but Borneo, Java and Sumatra are all on the same plate. Amusingly the angle between Banten & Lampung coasts at the Sunda strait matches the angle of the southwest corner of Borneo (my crude measurements [1] give 98.8° and 98.9° for the angles). Altho that one can only be a coincidence considering that the rest of the coast doesn't match. 89.172.8.50 (talk) 21:04, 27 February 2020 (UTC)[reply]
The forces of nature can do most anything. Note the likewise vaguely rectangular shape of the Hawai'ian island called Moloka'i. ←Baseball BugsWhat's up, Doc?carrots→ 21:35, 27 February 2020 (UTC)[reply]
Both that example and the one this section is about are primarily created by current sea levels. Ten metres higher or lower and the shapes may well be very different. Perhaps the question should be why the sea level is what it is today. HiLo48 (talk) 21:43, 27 February 2020 (UTC)[reply]