We have talked onions before. Keeping ability Depends on the type & variety of onion and how it is grown. The big sweet onions that we in the USA like to slice thickly for use on hamburgers are very high moisture, mild and sweet but are likely to start to rot in 3 weeks to a month (This includes the big reds & whites that are sometimes called salad onions) The medium yellow onions are the best keepers and are the ones liked for cooking, much less moisture when fresh and much more intense onion flavor. These can be carried over all winter if stored at cool (not cold) dry dark contitions. In the spring they tend to sprout no matter how they are stored. If you catch them when they just start to sprout the sprouts can be used like "green onions" and the bulbs will be very intense with a bit of bitter taste that will grow with the sprouts. MY theory is that the sugars stored in the bulb are being converted to feed the sprouts.Neko-chan said:Onions should keep well by themselves. I've never had an onion go bad. I keep them fresh for cooking. i have yet to understand the need to freeze or dry them.
Remember those potatoe onions I wrote about before? They keep much better than the big sweets but not quite as well as the common yellows.
If you are growing your own for keeping you need to "cure" them. that is the bit about knocking over the tops (which usually breaks off most of the roots) when the tops have started to brown the outer skin will dry up too as excess moisture leaves the bulbs. They will lose moisture until the outer skin is dry and paper like. From that point on they must be kept dry so if you want to spray with water to get off the dirt, do it BEFORE the outer skin dries up. When well cured you can either snip off the tops (leave a stub) or braid the tops together to make a kitchen decoration or gift
For the original question I make 4 kinds of onion relish (pickled) They are (no recipies) Fresh (w/ &w/o) mustard and carmalized (w & w/o mustard). Fresh I use sweet onions chopped, add some Ball crisping agent for crunch (look for it with the pickeling supplys, small can NOT pickling lime) then I use the same mix as for pickled beets with pickling spice, I love mustard so I add Coieman dry prepared mustard (It is Strong!) bring the vinegar/spice mix to a boil and pour into the onion packed jars. lids and rings usually seals. There is enough vinegar that I don't waterbath, carmalized- Yellow onions, sweet onions go to candy in this process. I use a dutch oven Full to sweat down the onions, but a smaller pan to get them to a golden or brown WITHOUT BURNING THEM. leave out the crisping agent and finish as above. I love them all but that doesn't mean you will. I like the Fresh on hotdogs and the carmalized on burgers or grilled meats. Make & use at your own risk.~gd
. They give up their oniony smell to the air around while drying, and it can be pretty overwhelming in the house. I set up my dehydrator on the covered deck, and do a full load, every year or so. I also chop some onions and keep them in the freezer, for those times when I only need a small amount.
