MDH

For the record, I have had this same issue occur with a batch of blueberry in which the blueberries were heat processed, strained of liquid, combined with equal the juice weight in sugar with an addition of acid. Years later, it remains in a gelatin state in the bottle. As I understand, the reason the pectin begins to structure is because there is a certain concentration of sugar, acid (which cranberries naturally contain a lot of) and water within the same solution. The fact that a given volume of your spirit contains mostly ethanol means that only a bit of water is reacting with a lot of sugar, acid and naturally occurring fruit pectin. So, needless to say, I am interested in how this turns out for you. Let me know.

Have you tried treating a sample dose of cranberry juice with pectinase and doing a test batch with it?

There are some niche situations where it would make a difference. If you have a yeast strain that metabolize hydroxycinnamic acids, it will contribute clove and medicinal flavors in 2-row with higher phenolic content. My understanding of it is rudimentary at best, but growing site and also seasonal conditions can affect the amount of phenolic acids that a grain will naturally produce.

What is the airflow like in your warehouse? What are your temperatures? A move from 30 to 53 gallons shows you want to age more efficiently or perhaps minimize wood impact - so would you be willing to fill to 65-70% of the potential volume? More airflow, higher temperatures and more empty space in a barrel means faster reactions of aging.

It was done already, but as a gin. I believe the client was Noma in Copenhagen.

Can also testify to this. Specific strains of lactobacillus will break citric acid down into diacetyl which is very undesirable for distillates that require grace, such as gin and fruit brandy. For this reason, fruits to be fermented spontaneously or controlled fermentations to be stored for a long time should never be picked in anything less than a fully ripe state; fruits that are unripe contain higher levels of citric acid.

Here is a Science Direct link which may be helpful to you: https://www.sciencedirect.com/topics/food-science/liqueurs Regarding coffee liqueur, there are several ways to approach it. If you are looking for more volatile, caramel aromas, make a redistilled liqueur with the beans. A major brand, Van Gogh Coffee Liqueur, has a variant which is just coffee distillate. If you want more body, do an infusion of beans. Or do both, and then blend them. I personally like to use medium to medium-light beans, but not too light or dark - the former being rather vegetable-like in aftertaste and the latter being acrid. I do a 24 to 48 hour infusion with the beans in chilled spirit - like a cold brew - and then quickly separate them. This allows volatility and body without anything acrid or astringent. Last but not least, the secret to a good coffee liqueur is to find flavors that are already in the coffee - dissect the beans like you would a spirit, wine or fragrance - top notes (most volatile) to base notes (least volatile) and then pair it with the flavors you find in it. So if your coffee has a bit of an orange aspect, add a little bit of orange. Or if it smells caramelly, add maple, and so on. All just in amounts enough to enhance the central coffee flavor but not overwhelm it. Sorry to be long-winded.

I don't have the time to do a full post today, but this reading may be of interest to you: http://www.alcademics.com/2012/11/essential-oils-and-cointreaus-centrifuge.html

Over-extraction simply tastes like too much of the oak characteristics. Hence, a highly aged product that is overextracted will taste very strongly of vanilla, wood, spices, caramel that one might associate from a Bourbon. However, astringency, bitterness and acrid taste exist in your spirit because it is simply underaged. Extraction does not equate to aging. It is only the very beginning of it. The components you have over-extracted now need to react with alcohol and other compounds in the spirit, and the most volatile fraction of spirit (Which even with a very effective head removal will always be present in newmake spirit) still needs to gradually be reduced through air movement throughout the barrel by varying forces (air movement in room, temperature swings, etc). So simply transfer your overextracted spirit to some well used barrels and allow them to age there conventionally. If you can find a very large barrel (a hogshead or sherry-butt for example), fill it only 60% of the way to allow faster interaction with oxygen and reduction in highly volatile compounds.

My personal opinion is that distilling outdoors is a constant battle for quality control - so-called "parasitic reflux" can be a huge issue, even with pots, making a complete headache of cuts.

The silvery film is the result of fatty acids and other large compounds forming complex larger molecules. Think of tannins in wine precipitating as the bottle ages. They are harmless and will not make it into your final product.

The tastings in San Francisco and London are committed completely blind.

I've asked about this before myself on these forums. My position is one of general skepticism for the vast majority of competitions, especially regional ones. The important are London, New York, San Francisco. The other important ones aren't awards at all, they're just influential people's opinions (eg the likes of Jim Murray, Robert Parker, etc). Media and those on the outer-circles of the industry (e.g. bartenders) do pay attention to these as well and often buy products which appear with top honors.

For convenience, I'd say dry is better, and is also much better for neutral if you plan for this to be used as a base for other spirits. But everything has volatiles. That's what we're doing, is capturing those. When you work with dry material, you don't obtain volatile flavors it once had. I've tried many potato vodkas - William Chase, Schramm, etc., all made with completely fresh potatoes, that were borderline potato eau de vie. So, it depends what you want.

Let me know how it goes, Andy.