Hop Dry picture tutorial

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Other tips you can utilize...

- Use a space heater to help raise your temps into the 100-130 degree range. (works great if you live in a hot climate with a garage that isn't well insulated!)
- flip the filters so the side nearest the fan doesn't overdry relative to the opposite end


BTW, this is essentially Alton Brown's method for herb drying applied to hops.

AB's beef jerky drying method I believe.

My hops were almost dry off the vine so just a few days on a screen and they were fine.
 
Hi, Nice info Thantos and everyone. I hope to read more on this.
I'll share what has worked for me so far. At harvest time it's still pretty warm here in punxsutawney so
I put them on screens in the basement out of sunlight for like others said about 3 days.
Then I weigh em, shrinkwrap em, and freeze em. I found that if I shrink wrap the hops in individual oz on brew day it's easier to gather what I need for a recipe without leaving half used open bags of hops in my freezer. I might have to build a nice drying rack like Zulu. Nice Rack:)
pic from my garden. I love hops. Virginia Wolf
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The easy answer is 8%, but that's really the target to hit if you are a commercial outfit trying to pelletize.

From what I have seen, anything under 12% is fine for storage and 20% and above is too wet. So the highest moisture content is somewhere between 12% and 20%. The lowest is about 6%. Below that and the bracts fall off.
 
Hmmmm...this makes me want to grow some hops!! I just got hopdirects email today about their hop rhizomes. VERY tempting!! Will keep this in mind for future ref. Thanks.
 
Just a note for those with the cheap-o dehydrators you can rig a regular old dimmer switch to the heating coil and then calibrate it yourself with a sharpie and a thermometer. Couple holes and mounted through the case and you've got some temp control on the cheap.
 
There's quite a wealth of information in this thread. Just thought I'd add a couple points from my own non-hop related experience.

I visited an herb farm near London, Ontario last year that had converted from Tobacco farming to herbs. They used a converted Tobacco Kiln to dry their herbs, but the most important change they made to the Kiln was to lower the temperature. I imagine their principles apply to Hops as well. When I asked about using a cheap home dehydrator to dry herbs, they said if there's no temperature control then its probably too hot. You're better off to air-dry without heat and take a long time than use too much heat. In culinary herbs, you lose a lot of flavour if you dry too hot.

As for target moisture, I'm a big hay producer myself. Our target moisture is below 13%. Anything above 16% has a high risk of mold growth. On the farm we use an acid-based preservative to prevent mold growth in the hay, so I imagine the moisture threshold for hops would be greatly affected by its pH. The more acid it is, the higher moisture it would need to be for bacterial growth. Its a big leap from hay to hops, I know... but you're still just drying plants, right?
 
This hop drying idea with the pillow case and dryer...

anyone care to elaborate on that? Now that its time to harvest my hops, im terrified im going to over dry them. Is there a way to dry them to much?
 
This is a copy from a post I put in a different thread, but relevant to the question you just asked.

It is possible to overdry hops but not easy unless you are using heat or in a desert. When they overdry, the bracts will fall off and the lupulin will fall out. If you are using heat, you may also dry out all the oils and aromas, leaving you with tasteless stigs.

Basically, every non living thing absorbs and desorbs moisture from the air at a rate that is controlled by the relative humidity of the air. For every Equilibrium Relative Humidity (of the air) there is a corresponding Equilibrium Moisture Content (of the hops in this case). If the Relative Humidity goes up, the item absorbs more moisture until it comes back to equilibrium. This is true for hops.

If you check my pictures, I believe I have an isothrem for hops posted. It basically shows that you can dry to less than 15% moisture content regardless of the air conditions. Assuming you are going to freeze them or use them right away, that is probably sufficient. If you are a commercial grower, you want to get to 8 to 10% moisture content, which means 50% RH or less. "Too dry" is somewhere less than 5%.

To hit 5%, you need very dry air for a long time. Or, you put it in a space that is really warm, which lowers the relative humidity, and poof...you have a pile of bracts and yellow dust. In that case, I just saw a thread where someone used the lupulin as a rub on his spare ribs. You can try that.
 
GVH_Dan said:
This is a copy from a post I put in a different thread, but relevant to the question you just asked.

It is possible to overdry hops but not easy unless you are using heat or in a desert. When they overdry, the bracts will fall off and the lupulin will fall out. If you are using heat, you may also dry out all the oils and aromas, leaving you with tasteless stigs.

Basically, every non living thing absorbs and desorbs moisture from the air at a rate that is controlled by the relative humidity of the air. For every Equilibrium Relative Humidity (of the air) there is a corresponding Equilibrium Moisture Content (of the hops in this case). If the Relative Humidity goes up, the item absorbs more moisture until it comes back to equilibrium. This is true for hops.

If you check my pictures, I believe I have an isothrem for hops posted. It basically shows that you can dry to less than 15% moisture content regardless of the air conditions. Assuming you are going to freeze them or use them right away, that is probably sufficient. If you are a commercial grower, you want to get to 8 to 10% moisture content, which means 50% RH or less. "Too dry" is somewhere less than 5%.

To hit 5%, you need very dry air for a long time. Or, you put it in a space that is really warm, which lowers the relative humidity, and poof...you have a pile of bracts and yellow dust. In that case, I just saw a thread where someone used the lupulin as a rub on his spare ribs. You can try that.

I planted 5 different types this year. I know that next year will be pretty good but when i harvest them in the summer and dry... Here is the big question AMOUNT? If i normally use 1 oz of cascade pellets how much do i use of my dried fresh stuff?
 
Perhaps this has been covered somewhere else, or it's common knowledge, but I haven't seen it anywhere so I thought I'd add it to this thread.

If you're shooting for 5-15% moisture then you should be aiming for 25-35% of your original mass. Just thought I should put that up here in case it hasn't been covered elsewhere.
 
Perhaps this has been covered somewhere else, or it's common knowledge, but I haven't seen it anywhere so I thought I'd add it to this thread.

If you're shooting for 5-15% moisture then you should be aiming for 25-35% of your original mass. Just thought I should put that up here in case it hasn't been covered elsewhere.

What does this mean. I had to throw all my hops out last year as I did not get them dry enough. I used a box with a screen attached that would hold about threee gallons of hops. The hops were 2-3 inches deep and I used a fan to blow ambient temperature air. I would measure a small sample of hops at the beginning and monitor until I was below 20%. I would occasionally stir them. To measure the moisture, I would pick out a sample of 20 hops of differing sizes.
 
What does this mean.
I'm not sure if I've posted this in this thread or just elsewhere, but here's the math behind the reduction in weight to 1/4 to 1/5.

The basic equation for determining moisture content of anything (hops, hay, herbs, etc.) is:

M% = ((Ww ‐ Wd)/ Ww) x 100

M% = moisture content(%)
Ww = wet weight of the sample
Wd = weight of the sample after drying​

If you want to know the moisture content, take a small sample and weigh it to get Wet Weight (Ww). Then get the moisture out. Either bake it or put it in a microwave to pull out the moisture. When you are sure it is completely dry, that is your Dry Weight (Wd). Now plug it in to see your starting moisture content.

I wouldn't use that Dry Weight sample in your beer, though. They are extremely dry, crumbly, the lupulinic resins have changed and you will probably burn them the first few times you try.

The problem for the homegrower is that you would need most of your crop to get an accurate enough reading of the moisture content...nearly a 1/3 of a gallon of hops if you have a balance that goes to 2 decimal places when using grams. So it is somewhat pointless.

Instead, let's assume the starting moisture content is 80%. (I have seen from 93% when picked in the rain down to 74% for some smaller cones. So 80% is pretty much the middle.).

Let's pretend we have a 1/2 of a pound of cascade that we picked out of the backyard. Since we are assuming that it starts at 80%, we can use the above formula to calculate the Dry Weight....0.1 pounds.

Now let's say we want to dry down to a final moisture content of 10%. (Commercially, we shoot for 8%, but 10% is fine since you aren't pelletizing.) with a moisture content of 10% and a Dry Weight of 0.1 pounds, the "Wet Weight", which in this case is the weight of the dried hops, would be 0.111 pounds.

Working that out, the ratio of beginning to end weight is 0.111/0.5 = .222 or another way to say it is that the final weight of the hops is somewhere between 1/4 and 1/5 the starting weight.
 
I had to throw all my hops out last year as I did not get them dry enough. I used a box with a screen attached that would hold about threee gallons of hops. The hops were 2-3 inches deep and I used a fan to blow ambient temperature air. I would measure a small sample of hops at the beginning and monitor until I was below 20%. I would occasionally stir them.

zrule, you main problem here was that the hops bed is too deep. At 2-3 inches deep, a box fan would not be able to blow through the whole bed so only the stuff on the top and bottom would be dry and the hops in the middle would stay pretty wet.
 
I'm not sure if I've posted this in this thread or just elsewhere, but here's the math behind the reduction in weight to 1/4 to 1/5.

The basic equation for determining moisture content of anything (hops, hay, herbs, etc.) is:

M% = ((Ww ‐ Wd)/ Ww) x 100

M% = moisture content(%)
Ww = wet weight of the sample
Wd = weight of the sample after drying​

If you want to know the moisture content, take a small sample and weigh it to get Wet Weight (Ww). Then get the moisture out. Either bake it or put it in a microwave to pull out the moisture. When you are sure it is completely dry, that is your Dry Weight (Wd). Now plug it in to see your starting moisture content.

I wouldn't use that Dry Weight sample in your beer, though. They are extremely dry, crumbly, the lupulinic resins have changed and you will probably burn them the first few times you try.

The problem for the homegrower is that you would need most of your crop to get an accurate enough reading of the moisture content...nearly a 1/3 of a gallon of hops if you have a balance that goes to 2 decimal places when using grams. So it is somewhat pointless.

Instead, let's assume the starting moisture content is 80%. (I have seen from 93% when picked in the rain down to 74% for some smaller cones. So 80% is pretty much the middle.).

Let's pretend we have a 1/2 of a pound of cascade that we picked out of the backyard. Since we are assuming that it starts at 80%, we can use the above formula to calculate the Dry Weight....0.1 pounds.

Now let's say we want to dry down to a final moisture content of 10%. (Commercially, we shoot for 8%, but 10% is fine since you aren't pelletizing.) with a moisture content of 10% and a Dry Weight of 0.1 pounds, the "Wet Weight", which in this case is the weight of the dried hops, would be 0.111 pounds.

Working that out, the ratio of beginning to end weight is 0.111/0.5 = .222 or another way to say it is that the final weight of the hops is somewhere between 1/4 and 1/5 the starting weight.

I think we arrived at similar destinations through different paths. However, I don't think you took into account the unchanging mass of the solid mass of the hops.

I remember reading somewhere that fresh hops are 80% water and 20% solid mass. So if we take an ounce of fresh hops, we have 0.80 ounces water and 0.20 ounce of solid mass. Upon reducing the moisture content to 10% we can defer that the make up of the overall mass will be 0.10 ounces water and 0.20 ounces solid mass, providing the drying process removed ONLY moisture. Our ending mass would be the combination of the final moisture mass and the solid mass, 0.30 ounces.

This is scale-able so therefore to achieve 10% overall moisture you want to shoot for 30% of your original mass.

In general terms....

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Upon reducing the moisture content to 10% we can defer that the make up of the overall mass will be 0.10 ounces water and 0.20 ounces solid mass

Oops! Moisture is measured as a percentage of current weight, not initial weight. Your example is consistent with the equation you posted, but that's not how moisture is measured.

The reason you don't measure moisture as a fraction of the original weight is that the original moisture content of the hops can vary quite a bit, depending on weather and humidity.

In your example, once you dry down an ounce of hops (that started at 80% moisture) to 10% moisture, the dry mass would still be .2 oz as you pointed out, and the water mass would be 10% of of the current (not the initial) mass. So you would write (ww -.2)/ww = .1 and solve for the wet weight, ww = .222 oz. The total weight at 10% moisture as a fraction of the total weight at 80% moisture is .222 oz / 1 oz = 22.2%

You both took into account the dry mass of the hops, but you just want to be sure you're expressing moisture as a fraction of the current mass of the hops, not the mass when they were picked.
 
Right...either way, the point is you are not dry until you are at a weight at least 1/4 of the original starting weight or less. But if you are less than 1/5, you are running the risk of being over dry. By over dry, I mean bracts falling off, strig snapping, lupulin falling out.

Just some further advice, you should get to under 15% to prevent spoilage. This is easily possible with using plain old air...no heat...no dehumidification...just air and time. You can tell when you start getting close because the bracts will start to open up like a pine cone. I usually see this start in the 22% to 17% range.
 
I just picked my first hops. I dried them on a screen with a fan blowing on them and a dehumidifier in the room. The humidity was 60%.
I dried them for two days, and they were very dry.
they seem to have lost all their cascade aroma. They smell like "grass" to me, not that kind, but regular old grass.
I think I let them stay too long on the vine. They were pretty dry when I picked them.

Any thoughts suggestions?
thanks
 
my first year hops didn't have that great of aroma either when dried, i'm hoping the 2nd year is better...
 
Randar said:
Other tips you can utilize...

- Use a space heater to help raise your temps into the 100-130 degree range. (works great if you live in a hot climate with a garage that isn't well insulated!)
- flip the filters so the side nearest the fan doesn't overdry relative to the opposite end

BTW, this is essentially Alton Brown's method for herb drying applied to hops.

I did this and the outside of the hops got really dry and crumbly before the center was even close to dry. Maybe I did not have enough air flow... temp was 128*
 
I did this and the outside of the hops got really dry and crumbly before the center was even close to dry. Maybe I did not have enough air flow... temp was 128*

Too much heat...too little airflow.

Heat is applied to lower the relative humidity. This helps drive moisture out of the hop cone because the air has the capacity to hold more water. The big boys do it so they can dry their entire days harvest fast enough to be ready for the next days harvest to come in.

Temperatures above 100F drive out your oils and other flavors. Temperatures above 140F degrades the alpha acids that give you bitterness. So they bring in massive amounts of air, heat it up to increase its desire for moisture and then pass them over the hops.

In your case, you added heat but there wasn't enough air movement so you just cooked the hops.

Why wasn't there enough air movement? A fan's airflow is dictated by the speed of the blade, shape of the blade and the pressure drop imparted on it. Speed and shape are decided by the manufacturer. Pressure drop depends on how much stuff you are trying to push the air through.

The box fan you used can probably do 2,000 CFM without anything in its way. (0 pressure drop). Put one of those 50 cent furnace filters (Just a mesh of fibers that you can see through) and the air flow drops to about 800 CFM. Put a second and the air flow drops to 350 CFM. Throw some hops in there and your airflow is negligible. Use a high quality filter and air flow is zero. Without airflow, the water can't be swept away.

By far, the best and least expensive method is to lay them out about 1 cone deep in a dry area on a screen. If you want to speed it up, blow air across them. If you really want to speed it up, put a dehumidifier in the space to drop the humidity level.
 
So I just dried some hops I got from a friend. I used a food dehydrator in shorter durations to try not to overdue it.
When I turned it on the 2nd time there was a great exodus of aphids. Now if I had air dried them would the bugs have left or just stuck around? I'm sure it was the heat of the dehydrator that drove them out. Personally I'm not to concerned because the hops will eventually go in a boil, but I would think some people would be more squeamish about bugs in there beers.

Anyone have any comments or ideas or had this problem before?

And of course I know one could take steps to prevent aphids from infesting the bush in the first place.. that's probably the best plan.
 
Ha...once the cone starts to dry, the bugs understand that their home/source of food is no longer and they will take off. In your case, you are right that the quick change of air flow and heat drove them out. Either way, they would have walked off on their own. Something to think about when you are selecting a location to do your drying.

This reminds me of a funny story of mine. Early on in our hop farming experience, we would dry the hops at a facility several miles from the farm. So we would pick the hops and put them in ventilated shipping crates that could drop into the oast. The crates were 4 foot long, so they stacked beautifully in the back of my minivan. So we would load up 4 foot by 8 feet up to 4 feet high of hops and away I would go. I would crank the A/C to start the drying process and keep them from spoiling. Well, that process also alerted the critters that change was afoot and they abandoned ship...into my minivan. This was a Saturday.

Sunday morning I load my wife, mother-in-law and 3 daughters into the hopmobile and head off to church. Halfway down the road, I hear blood curdling screams from the back seat. A big old spider has dropped down from the ceiling and is hanging at eye level between two of the girls. That's when everyone starts glancing around. There were spiders, stinkbugs and countless other creepy crawlies in every crevice of that van. While everyone went in for the Sunday morning sermon, I got a myself a can of raid and made a homemade bug bomb, waited 10 minutes, vacuumed up all the corpses, hit it with some air freshener and headed back to pick them up with a bug free van.

When we replaced that vehicle, SWMBO's first words as we drove off the lot were, "You will never, ever put hops in this."
 
Growing malting quality barley and then malting it takes a fair amount of space and is more of a challenge than growing hops...but yes, many do it. You will find posts about it in this section.
 
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