Onions 101

Onions, also known as the allium cepa, are a part of the allium family. There are more than 300 species of alliums including garlic, leeks, chives, green onions, and shallots. Alliums make up one of the most important culinary plant families adding delicious dimensions to many dishes! Since it is used quite often, I wanted to share a little more about the onion and demonstrate how I was taught to dice an onion properly in my food science class in college.

Onions 101  
Nutrition facts: Studies suggest that onions may help in lowering high blood pressure, reduce risk of heart attacks, and may even help protect us against cancer which is likely due to the presence of phytochemicals and flavonoid quercetin. 
1 cup chopped raw onion = 64 calories, 3 grams fiber, 2 grams protein, 20% Vitamin C, 4 % Calcium, and 2% Iron. 

Types: Fresh and Storage

Season: 
Fresh onions arrive spring and early summer - spring onions, sweet onions, scallions and leeks. 
Storage onions are picked at the peak of summer harvest season - pearl, cipollini, torpedo, red onions, and shallots. 
The perfect pick:
Look for the ones with dry, clean, paper-thin skin, and make sure that the onions are firm and heavy for their size. Choose firm bulbs with no soft spots, bruises, or other signs of damage. When picking garlic look for the bulb that is tightly closed and hard. Check for moldy spots, especially with fresh onions.
1 pound of onions = 3 cups sliced or about 4 servings of cooked onions
Storage: 
Spring onions - use soon after you buy them as they will only keep in the refrigerator for about 3 days. 
Sweet onions - if you plan to use within a week or so then you can leave them out on the counter. Longer storage put in a cool, dark place like an open brown paper bag or loose in the crisper drawer of your fridge on top of a piece of newspaper to keep them dry (avoid plastic bags to prevent molding from their juices). 
Storage onions - keep for months in a cool, dry, dark place. 
Cut Onions - use within a day or two. 

Another great thing to know is if your recipe doesn't call for all the onions you just cut, put the leftover raw chopped onion in a heavy duty plastic zip-top bag and freeze it for the next time you need to use an onion.
How to manage the tears and smells:
Tears - some things that I have found that works for me is to peel and chill in the refrigerator before slicing then use a sharp knife and good technique to get the job over and done with as fast as possible.
Smells - rub hands with a little of lemon juice or try rubbing fingertips on stainless steel (either run on a bowl of a stainless steel spoon under warm running water or rub the stainless steel kitchen faucet).

Preparing an onion:
Peeling small onions like shallots, pearl or cipollinis - place in a large bowl, cover with boiling water for 3 minutes, then drain. The skins should come of easily.

My demonstration of how to dice an onion properly:
(Sorry if the pics are little blurry - I had my husband take them and let's just say he's not that into picture taking ;)

1) Trim one end off but leave much of the root intact (I prefer to cut the stem end to delay cutting the root end which has the stronger odor). This way you will have one end to keep your fingers on while cutting.

2) Cut in half from end to end.

3) Peel each half. 

 4) Lay one half on it's cut side. Make one or two horizontal cuts (how many cuts depends on the size of the onion), keeping the knife parallel to the cutting board - be careful not to cut through the root end. 

5) Make parallel vertical cuts from the root end to the cut end, again make sure not to cut through the root end. Space the cuts as wide as you want your dice to be.

6) Make a series of cuts perpendicular to the previous cuts, space them out as wide as you want the dice to be. Hint: Keep the fingers on the onion curled so you want cut your fingertips off!