Multiple drying options, which is best?

My work gives me several options to dry my incoming harvest, curious if anyone has any opinions on which is best?

Convection oven, temperature can be lowered

Typical fan/filter method as illustrated in the sticky

Placed in a box to create a chamber, and pump dehumidifed, or dessicated air in (Could get too hot? No control over the temperature, i've seen it as hot as 125F)

Freeze dry.

Any thoughts? Thinking of picking up a bag of hops from the local store that have already been dried, and trying them all to see if freeze drying can over-dry them, if thats possible, I have moisture measuring equipment to check percentages and be accurate, just wanted thoughts.

I'd go with the sticky. There are some oils in hops that become volatile at temps over 100*F, so that would drive out a lot of awesome flavors and aromas.

No to the convection oven and any method that gets you up to 125F.

You are growing these hops to give you bittering and flavors. Flavor and aroma come from very delicate oils and other volitiles that dissipate quickly as temperature goes up. The four primary oils in hops are Humulene, Caryophyllene, Farnesene and Myrcene. Farnesene has a boiling point somewhere in the 85 to 95F range, so if you are above 100F, you are definitely sending that one away.

So the idea is to use the lowest temperature air possible. You could use the desiccant to get the low RH but be cautious of the temperature rise.

By the fan/filter method...I'm guessing you mean the "Alton Brown" method of placing them between two 50 cent filters and attaching it to a box fan? I do not like that method. Box fans cannot handle a large pressure drop and that is what you are doing with that method. You are much better laying those filters out flat, or using a screen, and blowing air across them. Then they don't get squished, have more airflow, don't get imbedded with filter fibers, etc. That's the method I recommend to all home growers.

Freeze dry...this is something I have looked into but found it could never work on a commercial scale because of the economics. On the home grower scale, why not? it would be a great way to preserve the oils and aromas.

Could you over dry? Sure, you can over dry using just about any method. the danger of overdrying is that the cone shatters (falls apart) and you loose the lupulin. In the case of freeze drying, its frozen and contained in some sort of vessel. So if you overdry, I don't think you would loose the "good stuff" as easily. The only problem now is that you have a more concentrated hop and when your recipe calls for "1 oz", that 1 oz is going to pack a much bigger punch than the stuff you get at your LHBS.

It sounds like you want to access what you have available through work and I don't have any experience with those methods but I use a food dehydrator/jerky maker with the control knob set down to the lowest setting (95 degrees) and it works great...

I haven't had a chance to do my experiment with the vacuum freeze dryer. Hopefully next week when I'm not on call. I'll see if there are any detrimental effects if being in a vacuum.

Obviously, they won't look as "pretty" when you thaw them because the large ice crystals will break the cell walls but it shouldn't effect their performance. To be on the safe side, I would probably throw them in while they are still frozen so it doesn't fall apart. Most likely the ice crystals will rupture the lupulin glands. Not the end of the world since its the same thing that happens when we make pellets, except the process of pelletizing holds it all together. Loose whole leaf won't do the same.

But please experiment and let me know. I've been trying a number of other things myself. A lot of them would probably work well for a homegrower but doesn't scale up well for commercial growing.