Alcohol is one of those relatively unique items that you want to have with you everywhere but that people would really rather you not have with you anywhere but dark quiet places like bars or your house. This has historically not stopped anyone who really wanted to drink. To be honest it simply makes the serious Teetotalers look silly. The lengths to which people will go to make the anti-drinking zealots feel better is somewhat absurd. The number of crypto-flasks has exploded in the last few years. The Wine-Bra, Wine-Purse, Booze Tampon, Sunscreen flask, Shampoo Flask and flip-flop flask all speak to the same desire, to keep a usable quantity of alcohol on your person or in your luggage.
So let us take a look at the tools of consumption for a moment and examine what makes for a good flask.
Item 1: Volume
The primary function of a flask is to provide enough alcohol to get you comfortably inebriated. If that’s a single glass of wine you might not need more than a couple of ounces. If you’re trying to keep shots for you and 4 of your closest friends you are going to need something a bit bigger. A single shot is in the order of 1.5oz, a glass of wine 4-8oz, a beer 8-16oz. Leaving carbonation aside as a factor a 16oz flask is going to be at best the size of a small book. A 2oz flask can be about the thickness of a matchbook or the area of a credit card. Given this need there is something for everyone out there from the simple metal 2oz to the comically large 64oz flask. Which I would argue is actually more of a flask shaped growler than any kind of portable drinking solution.
Item 2: Size
The inverse of volume is size. A key component of concealment is the ability to fit your flask inside something else that doesn’t look like a flask. Because our contents are liquid their actual shape doesn’t matter but the size of the container can make a great deal of difference. The classic metal flask styling has a gentle curve to it that allows for it to be placed against the body at hip, leg, or arm. To increase the size of a flask one has to either increase the thickness of the flask, or increase the surface area of the sides. This rapidly becomes a question of ratio, if something becomes as thick as it is wide you’ve got a cube which is not a functional shape for our purpose.
A second factor to size is that in general the flask itself serves as cup as well as bottle. This means the flask needs a certain amount of thought given to how it fits in the hand. Boxy or awkward flasks are going to be difficult to withdraw, use and remove without undue difficulty.
Item 3: Shape
More than just size here we come into the second factor of concealment. Natural camouflage is a helpful method of avoiding undue attention. Some things are going to be better in this regard than others. The cellphone, camera or Ipad flasks are all going to elicit some concern as they aren’t normally something you put to your mouth. While they try hard, these flasks are only going to fool someone at an extreme distance. The items in question are too ubiquitous to fool anyone with their cheap construction. Similarly the sunscreen, shampoo or toothpaste flasks are going to raise an eyebrow, as seeing someone drink spf 50 isn’t terribly common. In this case the normal flask shape is even less helpful as flasks look exactly like what you expect booze to come in, and are seldom used for anything that isn’t suspect.
Item 4: Cleanliness
As with any drinking vessel once you have used it the problem becomes how to clean it. Peach brandy sounds great for a single outing, but left too long it’s entirely possible that everything you drink afterwards will taste like peaches whether you like it or not. The only real solution here is to put the same thing into the flask every time. Off flavors aren’t always going to show up, but in such a small volume you’re going to get flavors what whatever was there before with even a minor amount of residue. Now it is important to note that you should not leave alcohol of any kind in a flask. Alcohol is a solvent, it will strip just about anything that it is possible to strip and high proof things like whiskey and vodka operate more quickly than low proof liqueurs. High sugar things like liqueurs and creams have the added problems of sugar and milk products. Sugar eventually becomes gummy, or separates or settles which given the smaller size of the flask opening makes it almost impossible to remove. Use your flask quickly, wash it as soon as possible and be sure to leave it open to dry. Getting a small selection of bottle brushes or pipe cleaners is a good preparation for those times when you forget a flask of fireball in a coat pocket.
Do not use soap. Liquid, powder or gel it doesn’t matter. No matter how careful you are there is always going to be the potential for off flavors being left by whatever residue the soap imparts. If you thought peach was a bad flavor for bourbon imagine what dawn is going to taste like. Your best bet for cleaning a flask with some kind of residue is vinegar and baking soda. Sure I hear you say, “vinegar? ” The potential residues aren’t toxic, the flavor doesn’t stick around long and the interaction will get even the gummiest rock candy nonsense out of your tiny hip flask.
Item 5: Temperature
There is nothing in the world worse than hot booze. At least hot straight booze. This is doubly true of wine and beer. Most of the better class of flasks are made of stainless steel, which while excellent for holding shape and keeping clean is a fair conductor and container of heat. Lacking any real insulation a hip flask is going to very quickly heat your tipple to body temp which is at least 10-15 degrees higher than desirable. Similar problems can be had with the bra flask and any other item where concealment puts the liquid in close proximity to your body. Double walled vacuum insulation is possible in a pocket flask but this will almost double the size of the flask without increasing the actual volume. Uninsulated flasks can be carried in a bag or backpack but this increases the necessity of camouflage. Appearing lower on the list than any of these previous concerns means that focusing on temperature may result in problems elsewhere.
In the end the flask that works best is the flask you have at hand. My desk is awash in flasks of varied sizes, construction and material. None of them are perfect but each serves the purpose in a different way.