From what I have gathered, there's 3 ways to preserve gummies, this guide is not written by me, but I've modified it to suit the needs of the alt-noid community best.
M E T H O D # 1
C I T R I C A C I D / S U G A R
A favorite method of coating gummies is with a mixture of citric acid and sugar. This mixture provides crystalline texture on the outside as well as visual appeal. The real power with this coating is in the citric acid, it can provide enough tartness to accentuate flavor or enough sour kick to make you pucker your lips. The balance is entirely up to you, but a good ratio to start with is 1:4 acid to sugar. This mixture won’t be sour enough to blow your socks off, but will give a nice mild tartness. This ratio can be increased if so desired based on personal preference, you can even leave the acid out altogether.
When coating your gummies, the process is very straightforward. The prepared mixture of citric and sugar can be sprinkled overtop of the freshly popped product, or the gummy can be added directly to a bowl of citric and sugar, tossed, and then removed with a mesh sieve. The use of a mesh sieve is extremely helpful in separating the gummies and removing any excess coating that may be stuck to the surface. After coating with citric and sugar, these gummies can be allowed to cure in a dry space for a day or so to allow the sugar and citric to form a shell-like coating. After curing, package your candies in an airtight container and store in a cool dry place to maintain quality.
This is a fairly simple and flavorful method to coat your gummies for palatability and appearance. The only thing to keep in mind with sugar coatings is that sugar loves water and has the ability to pull water from the surrounding air which can cause the formation of a sticky syrup on your gummy product. Maintaining low humidities in storage and cure spaces will help prevent this before packaging and storage.
M E T H O D # 2
C O R N S T A R C H / P O W D E R E D S U G A R
Another common method used for coating gummies is with a starch, usually cornstarch, which acts as a desiccant that is able to dry products to prevent sticking and dripping of moisture. Cornstarch is used to create a thin skin-like layer between the outside air and the sticky gelled gummy within. A portion of this corn starch can be combined with powdered sugar to help prevent the dry mouthfeel that these starch coated gummies impart (a 1:1 ratio starch to powdered sugar works). The coating of starch also gives the final product a matte finish which can be nice in the right form factor, looking like a weathered beach glass as opposed to a clear polished one. Cornstarch should be used directly after removing gummies from their molds, sifted over a fine mesh sieve that will remove the excess starch that has caked on, and then cured for at least a day in a dry cool environment before packaging.
M E T H O D # 3
C A R N U B A W A X / V E G E T A B L E O I L
Another effective coating product used to eliminate the loss of water and prevent excessive drying while also providing a polished appearance, is carnauba wax. Carnauba wax is a naturally derived wax from a Brazilian palm plant; Copernicia prunifera.
To use carnauba wax, dissolve it in a flavorless oil (carnauba melts at ~180F) at 5% by weight of the oil you’re dissolving into. Any flavorless oil will do (vegetable, canola, peanut etc) the choice is up to you. In the coating process, a little goes an extremely long way and will spread when agitated with other gummies.
For small batches, what I have found to work with ease, is prepping a small volume of oil (47.5g oil with 2.5g carnauba wax to make 50g of coating, which can be stored for later use) working with gloved hands, apply a few drops to your palm and massage the coating mixture into your gummies in a mixing bowl. Repeat this step until an apparent coating can be seen.
Continue to toss the coated gummies in a mixing bowl for several more minutes (this may take a little elbow grease) allowing the coating to evenly distribute between pieces.
The key to this process is using as little oil mixture as necessary, so there is no excessive dripping or saturation of oil. The final product should be a polished coated gummy ready to be cured for another day or so in a dry space and then packaged.
Coating gummies is meant to extend the intended shelf life of the product as well as impart various flavor or textural qualities. No matter where you land on which method to use, your final product will be a higher quality that don’t stick together and lose less water over time. There is no one perfect method, and all should be weighed for their intended application (drying/ flavoring/ anti-stick).
These coating techniques are well suited to make a relatively valuable homemade product last longer without a loss of quality.