Saturday, 21 November 2015

Know your Onions ? and how to chop.

Know your Onions ? and how to chop.
The onion plant (Allium cepa) is unknown in the wild but has been grown and selectively bred in cultivation for at least 7,000 years.
The ancient Egyptians worshipped it
believing its spherical shape and concentric rings symbolized eternal life.
Onions were even used in Egyptian burials, as evidenced by onion traces being found in the eye sockets of Ramesses IV.

The Onion Futures Act passed in 1958, bans the trading of futures contracts on onions in the United States.
This prohibition came into force after farmers complained about alleged market manipulation by Sam Seigel and Vincent Kosuga at the Chicago Mercantile Exchange two years earlier.
The subsequent investigation provided economists with a unique case study into the effects of futures trading on agricultural prices. The act remains in effect as of 2013.

Great post Lacerant Plainer thanks
#knowyouronions #onions

Originally shared by Lacerant Plainer

The Onion :  The onion (Allium cepa) is used as a vegetable and is the most widely cultivated species of the genus Allium. The humble Onion has been cultivated and modified by humans for over 5000 years.  Onions have been used for their medicinal properties and in food down the ages.

What makes you cry when cutting an Onion? : The component in an onion that makes your eyes water is called lachrymatory factor, from Latin lacrima, or “tear.” (How appropriate is that!) Lachrymatory factor irritates the eyes and stimulate the tear glands to produce tears, much like the action of a tear gas. Onions are rich in two health-benefiting compounds: flavonoids and sulfur-containing compounds. Flavonoids are potential antioxidants that could protect us against cancer, heart disease, and aging. They are often found at high concentrations in the skins and outer layers of onions with yellow or brown color (but some are masked by red or purple color).

Tear-free (GM) onions have been developed by Crop & Food Research (NZ) and in Japan : As a matter of fact, inhibiting lachrymatory-factor synthase would not only stop onions from making your eyes water, but would also increase the yield of thiosulfinate because all the sulfur compounds released from onions will be converted into thiosulfinate. So the onions lacking lachrymatory-factor synthase activity would be tear-free but retain that odor and flavor distinct to fresh onions.

How temperature affects potency : When temperatures drop, reactions take place more slowly because all the molecules have less energy. So, chilling onions in the fridge before chopping them reduces the amount of syn-propanethial-S-oxide that can be produced. Freezing the onions works even better, in fact it completely disables the enzyme, although it might make chopping a bit more challenging.

Common myths : Powering an Ipod with an onion, rubbing your hands with stainless steel reduces the smell of onions (This is a commonly held belief, but there is no scientific evidence to support it, though one can theorize why it may happen). Rub an onion on your foot and you can smell it 30 minutes later....This is definitely not true. Can onions reduce the smell of fresh paint (fumes)? .... there is some truth in this, though part of it is psychological.

Medicinal uses : Onions have been shown to improve cardiovascular health, blood sugar lowering abilities and blood thinning properties.

Smelly Chemicals (The organic Chemist's view) :

Wikipedia link : (link to main pic on left).
PBS link:

Additional reference:

A little bit of history :

Pic credit for pic on right:

#onion #science  

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