What are the grey-black specks that appear when whipping cream in stainless steel bowl

The main goal with temperature is to kill anything nasty. Those nasties die based on temperature and exposure. Much like a human could live forever at 95 degrees, for a long while at 110, shorter while at 150, and would die instantly at 750, so for all the stuff in Pork. 160 is considered a safe temperature because at 160, everything dies instantly. The FDA has a chart for all this, here. You'll see that even 120 degrees is safe IF you cook it for 21 hours!

I cook a lot of sous vide, so these temperatures and times are easy to get and be precise about. The thing you need to be careful about is that the time table shows the amount of time that the whole piece of meat needs to be at a given temperature, so make sure you heat it through before you start counting.

I'll regularly do pork chops in the 135 range, and it's lovely and moist without the stringy overcooked texture you get when well done.

Ok... I'm going to ruin your day with this. In orange juice for instance, the process of homaginization and storage kills the flavor of orange juice, so the industry has enlisted the help of the perfume industry to help them. Each orange juice company has basically a perfume of orange flavors that it uses from the peels and rinds and biproducts that it uses to try to recreate the taste of real orange juice... It's why every orange juice brand tastes slightly different even though they are all "fresh squeezed" (btw, they are technically fresh squeezed, they're just then stored :))

If you google "orange juice flavor packs" you can see what this is talking about. The flavor packs are incidentally made out of parts of the orange, so the fda has no problem with them (sadly).

http://consumerist.com/2011/07/oj-flavor-packs.html

So to directly answer your question, you can flavor something with fruit derived perfume and call it "natural flavors"

Here's a quote from the site:

Juice companies therefore hire flavor and fragrance companies, the same ones that formulate perfumes for Dior and Calvin Klein, to engineer flavor packs to add back to the juice to make it taste fresh. Flavor packs aren't listed as an ingredient on the label because technically they are derived from orange essence and oil. Yet those in the industry will tell you that the flavor packs, whether made for reconstituted or pasteurized orange juice, resemble nothing found in nature. The packs added to juice earmarked for the North American market tend to contain high amounts of ethyl butyrate, a chemical in the fragrance of fresh squeezed orange juice that, juice companies have discovered, Americans favor.