Before I begin my answer to this question, I would like to inform you of the recent article I published on my homepage. Its topic is cooking, and in it I have covered several different forms of food preservation. It is very detailed and could be of some use to you as it contains details on coconut preservation. If you look at the comments, others have also given their opinions, and although I can't include them in my answer without infringing copyright laws, I sincerely recommend them!
Topic: Best Ways to Store an Open Coconut.
There are several good ways to store an open coconut, and they all depend on what kind of environment your in. For example: is your area hot or cold? Humid or dry?
I will write my answer assuming you are based in Chennai as that is what it says on your query.
1. Cut the coconut into small 3-inch cubes. Ensure when cutting that the cubes have clean edges, not ragged, so that that juice inside the coconut doesn't leak out when stored.
Wrap each individual cube in a small square of Polythene paper (this is often available at your local grocery store, generally around 30 rupees for 5 meters), place the wrapped cubes in snap-lock bags and freeze. Remember to check that the freezer temperature is under -10 degrees Celsius.
When you want to use the coconut, open up as many cubes as you will need and defrost/thaw for 15-20 minutes, or, until you can hold the cube in your bare hand for more than a minute without getting hurt by the cold.
Note that this method of preservation can keep the coconut fresh for around two to three weeks.
2. If the above method doesn't appeal to you, this is a good alternative!
Cut the coconut into even quarters and pack each one in micro-freeze bags. After putting them in, prepare a solution of lemon juice and salt. In each micro-freeze bag containing a coconut, add two teaspoons of salt and squeeze 3 lemons. This helps the coconut slow down the process of rotting.
Once you have added the mixture to all the coconut quarters, deep freeze them in their micro-freeze bags. This preserving method makes them last up to one week. When using the coconuts, first wash it to remove the lemon and salt mixture, and then microwave or thaw it. It is important to wash them before microwaving, or else the lemon mixture is absorbed by the coconut, giving it a bitter, sour and tangy taste.
3. This method doesn't preserve the coconut as long as the others, and is mainly useful if you don't have access to, or do not want to use a freezer. However, this method keeps the coconut more fresh and juicy then the other procedures.
Cut the coconut into thick, wedge shaped slices.
Buy or peel banana fresh banana skins, and wrap these around the wedges. Make sure that none of the coconut is left uncovered. This preserving method operates on the basis that the banana rots before the coconut, keeping the coconut fresh. It may sound a little odd, but this is the method I generally use, and believe me, it works!
Store the banana wrapped coconuts in a cool, dry place and wash before eating.
The coconuts will not rot for around 5 or 6 days.
One thing to remember with this method is that the banana skins will smell horrible when they rot, so make sure the coconuts are stored in a place where the smell won't bother you!
1. Remember that no preservation method will leave the coconut how it originally was. If you need an extremely fresh coconut it is easier to buy a new one!
2. Never re-freeze a coconut, or any other food for that matter, after thawing it!
3. Most importantly always remember to drink water after eating coconut, as it has scientifically been proven to balance the alkalinity of a coconut. If you eat large portions of coconut and do not drink water, you will feel stomach aches or pains.
Hope this helps, and best wishes in your preserving!
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