Vacuum Packing Coffee Results 2

A weeks on and more news

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OK, It's one week on and things have been working out really well. I roasted up a batch of coffees for testing

  • Colombian Supremo
  • Sumatra Manheling G1
  • Nicaraguan Maragogype
  • Brazil Fazenda de Lagoa Peaberry

Now a few things I did differently, although I am not sure how much difference it makes (beyond the first re-vacuum). As the coffees degass, I was re-vacuuming the bags. I am pretty sure the 1st re-vacuum could actually flush out those last traces of Oxygen the initial vacuum may have not removed. The dilution with the CO2 from degassing, helping to remove it. I did, however, diligently remove the gasses every day or two. I had some coffee friends round and we simply did our normal drinking coffee and chatting thing. The big difference was their reactions to the coffee. They felt the smell was fresher, richer and seemed to have more flavour about it. The taste was perceived as more complex, fresher and….well yummy. The coffees seemed to come alive in the cup. I simply smiled, as I had been enjoying the experience of "new" coffee tastes for a while now.

One of my friends had some Guatemalan Finca Isabel, he had roasted 3 days ago and I had my 12 day old roast of the same bean (or what was left of it). I had been re-vacuuming the bag after removal of beans to make coffee. We compared the smells of the coffee….unbelievably the 12 day old roast smelt better and the roasts were pretty much to the same degree. It's not that his roast smelt bad, it simply smelt as it usually would (and as mine used to), the vacuum packed roast was just more complex and came alive. We pulled some shots from this roast and they looked identical to shots poured 3 or 4 days post roast and tasted great.

The other thing I have been noticing for the last week, is the fantastic smell of the gas that comes out of the bag when you re-vacuum to remove the degassing CO2, it really is out of this world.

Next for me, is a test of a future batch of coffees, where I allow them to degass for a day or two and simply re-vacuum them once only, just to get any residual oxygen out. I also want to find out if continual re-vacuuming is bad for loss or destruction of aromatics. But I am in no rush to do this

People have been asking if I have done various more complex tests and comparison tests…no I have not and probably won't rush to do them. The main reason is…I don't need to, the taste difference is so obvious. Both my friends after tasting the difference, decided to adopt the system, one got up early this morning and went to Lakeland in Guildford to buy his sealer and bags, the other has just a set of bags and intends to use mouth suction only (which actually does a reasonable job).

One point to stress and I do keep emphasising this, I like the use of a plastic bag, because the vacuum process removes air, but isn't as "hard" a vacuum as if the coffee were in a rigid container. I am not sure if that sort of "hard" vacuum would be good for coffee or the volatiles it contains. it's also the reason I am considering a single re-vacuum after a day or so degassing, but that's all (apart from air removal after opening the coffee and resealing it).

Something else to consider is the ability to take pre-ground coffee into work, without it spoiling within hours….I can't be sure, but think this system would also be ideal for that purpose, especially as the bag can be resealed by mouth suction, saving having to carry the vacuum machine itself into work.

Some guesses at what I think is happening (speculation)

I can't be sure, but I think that after roasting, different compounds either continue to be formed or gradually migrate to the surface of the bean, perhaps both. I think the oxidation process happens far faster than we realise and certainly within hours after roasting, significant oxidation may take place. I try and pack the coffee as soon as possible after roasting e.g. 10 min.

A question that has bothered me is why the roasting process itself doesn't create significant oxidation and the only answer I can come up with, is: Possibly many of the compounds take time to form during roasting and are not as vulnerable and are perhaps locked deeper in the bean.

I also think that staling, one started is a destructive process, and even if the supply of oxygen is used up in any standard container or one way valve bag (which is doubtful), continues to degrade the coffee. I was concerned that oxidation could be responsible for proper flavour development, but I no longer believe this is the case.

Because coffee is hard and brown, it's difficult to believe such short exposure to oxygen can cause damage, but one of the reasons I started all this was slicing some apple for my kids and literally watching it go brown in minutes! now I can't be sure that any compounds in coffee can oxidise this rapidly….but what if they can!

So where does that leave further tests to convince others to adopt this method……the quick answer is, I don't care icon_wink.gif, if you want to try it, feel free to do some tests, if you think it won't work, fine. Me, I will do more tests as and when it's convenient….but I don't need any more convincing. As far as I am concerned, it works so well, further testing would be almost pointless, although I am curious to know how long, coffee will remain great tasting packed this way.

Now, I must remember to buy shares in Vacu Seal