Why are fresh eggs useful when cooking meringue

There are two components to flavor: aroma and taste. The wonderful smells you get are the volatiles of the ingredients you have been cooking, and while they add a lot to dishes, aromas are just part of what makes food enjoyable. One also needs to worry about taste, and that may be the missing part. When I decided to improve my cooking three years ago I was mystified by flavors. I wanted to know how spices worked and how to use them better, but all the reading and experimenting did not help my cooking.

Then I learned the Remick Maxim (lower the temperature when possible) and the quality of what I made went up more than in the entire previous year. I then heard Thomas Keller speak about salting and things clicked. One has to get the salt, acid, and sweetness of the dish right or everything else amounts to nothing. Once I learned to pay attention to taste, spices became easier.

The next steps have been:

• Understand caramelization (the Maillard process or reaction), it is a great source of flavor.
• The main ingredient needs to be rich in flavor. Even something as simple as rice will make a difference. Try making rice with Basmati from India or Pakistan, where they age the rice before selling.
• There are a lot of underdeveloped recipes out there. Beware.
• Use spices in groups that traditionally grow in the same region. Cumin and coriander, basil and thyme.

I don't remember the exact science behind the potatoes not turning to mush ... I know it was discussed on an episode of America's Test Kitchen, and they even discussed the amount of vinegar and how it affected the window for cooking times. (I want to say it was on an episode where they were making an Austrian potato salad)

... and it's not specifically vinegar, and not solely potatoes. Acids will stop quite a few items from softening when cooking. I know the list inclues onions (pre-cook onions before adding acids if you want them to disolve into a sauce), potatoes, apples ... I'm guessing there's others.

For potatoes and apples, most recipes claim it's to slow down browning. You see it in potato salad, but not mashed potatoes. You'll see it in apple pies, but not in applesauce ... because they'll come out lumpy.

Matt already mentioned three uses for vingear:

• as half of a chemical leavener
• tenderizing / marinades
• preservation / picking
• coagulation (eg, when poaching eggs)

But also :

• stabalizing eggwhite foams (might just be a variation of coagulation?)
• denaturing / "cooking" (eg. in the case of ceviche; a variation of marinating?)
• flavor (might not be a 'science case' ... but sour is one of the primary tastes; especially helps to balance out fatty dishes)
• cleaning / disinfection (might not be a 'cooking' use)