There are two problems with making rose vodka:
- anthocyanin (color) stability
- aroma stability
The problem with color stability is that rose petals contain anthocyanins (which give them vibrant colors) but no polyphenols (tannins) whose presence would stabilize the former and prevent their oxidation which manifests as browning.
One option to overcome this is by making a rose syrup by simmering petals with sugar and water. As the water evaporates, the mixture reduces into a thick syrup and somehow fixes the color.
I have never had enough roses at once to make this stuff in substantial quantities. I have different varieties of roses in my garden, but only a few have the color and aroma I want to put in my rose vodka.
So I was forced to find a way to achieve color and aroma stability while I do a cold extraction by infusion: soaking petals from one rose at a time in a high-ethanol solution. I tried citrate, tartrate and sulfate as well as combinations of all three without any success. Finally, John Baume clued me into ascorbate (i.e. vitamin C).
When present in abundance, it prevents oxidation and keeps the color a vibrant fuscia pink. One has to be careful, however. At low concentrations, ascorbate becomes a pro-oxidant. Considering the cost of generic vitamin C, I usually put a few grams in an extraction vessel and stir periodically before I water back to 80 proof.
This keeps the color stable, but the flavors still take on a wilted rose petal quality with a little time – perhaps from the oxygen introduced when I pull out spent petals.
I decided to go back and make a rose sugar used by confectioners and bakers in Europe. I took the petals from a couple of roses and ground it with some sugar in a mortar and pestle. Because I had only a small amount of this paste, I added a bit of water and pectinase, planning to make a syrup. Unfortunately, I put the jar with this concoction in the cellar and forgot about it for a few days while I got busy with other things. When I checked in on it, it had already begun to ferment. It smelled clean so I added more water and sugar, a pinch of DAP and some Côtes de Blanc yeast – which took over the ferment very quickly.
Since that time, I have added a few more roses, and as the volume grew, I moved the must to a 1.5L jug with a stopper and air lock, added some tartrate, more water and sugar and still more petals. It smells great and my hope is to get this finished with some RS, top off with some vodka or rectified spirits, add more ascorbate, let it settle, rack off and blend with the extracts I already have.
In the meantime, the ferment smells fantastic and that is what has me wising for Smell-O-Vision. Those who have ever smelled confectioner’s or baker’s rose sugar or rose water, will have some sense of how this smells.