Knockbox Mold

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marinewonder

#1: Post by marinewonder »

I get mold on the bottom of my knockbox.

I dump that thing at least every 3~4 days as we drink a lot at home.

I use a plastic knockbox, similar to the Cafelat Tubbi.

I see a lot of people tend to advise to simply empty the thing out every 3-4 days, and maybe that's sufficient in most cases.

But in my case, my pucks may be particularly wetter, I admit in some cases soupy, and while I know I can play with the grind size and water quantity to reduce this (i.e. increase grind size, reduce water), I'm too impatient to try to dial that in, as I cycle at least three different coffee types at any given time, all with different dryness and I keep one single grinder setting which gives a slightly different grind-size for each coffee bean type.

With that said, I know I can improve my method.

But I still think a knockbox should be able to release all material better, regardless of the bottom collecting seeped moisture from the pucks as they collect in the knockbox.

I don't want to have to wash and dry out the knockbox every 3 days, I don't think it makes sense to have to do that to what's essentially an interim trashcan.

Has anyone dealt with this issue by choosing specific materials of the knockbox, is stainless steel better perhaps?

Are there "teflon" coated knockboxes to avoid this completely?

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redbone

#2: Post by redbone »

You can always line it with a plastic bag or sticky plastic film like Saranwrap.
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Rob
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civ

#3: Post by civ »

Hello:
marinewonder wrote: ... mold on the bottom of my knockbox.
Like most everyone else living in areas with a certain (suitable for mold) combination of AT+RH.

I always get mold in my knockbox made from a large plastic drainpipe
More rapidly in the winter months.
I have never been there, but I bet Las Vegas residents don't have too much of a mold problem.

The spores that mold come from are in the air, all around you, it is generally referred to as wild yeast.
Different places/geographies have different types of spores.

They settle on/around the pucks and that's it, mold will start to grow as long as they have the proper conditions.
And it's not related to the knockbox's materials, it is just that the damp pucks are very welcoming to them.

BTW: those very same spores (wild yeast) are the ones responsible for the fermentation of the sourdough starter used to make delicious bread, among many other edible/drinkable things.

Industrial yeast production is one of the most important business enterprises in the world, moves billions every year.
marinewonder wrote: ... empty the thing out every 3-4 days ...
That's exactly what I do.
marinewonder wrote: ... my pucks may be particularly wetter ...
Just being damp is wet enough.
marinewonder wrote: ... a knockbox should be able to release all material better ...
You may want to try with a cheap teflon lined pot and see if you do better.
marinewonder wrote: ... don't want to have to wash and dry out the knockbox every 3 days ...
If you have a garden, coffee grounds make excellent compost material.
But still, your knockbox will still need to be cleaned.

Best,

CIV

dmw010
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#4: Post by dmw010 »

I dump my knockbox out every day, wipe it out under the tap and let it air dry. No mold, cleaning takes about 5 seconds.

jgood

#5: Post by jgood »

I dump it out every day and haven't had any issues. Takes a few seconds. Maybe rinse it out every week or two. But once mold is established I think it needs a serious scrub and soak in a mild bleach solution.

jpender

#6: Post by jpender »

civ wrote:The spores that mold come from are in the air, all around you, it is generally referred to as wild yeast.
I think mold and yeast are different creatures, both fungi though, and both ubiquitous in the environment. I don't use a knockbox because I would expect to have to clean it periodically. I tried using one a while back for presspot grounds and it always molded after a while.

jrham12

#7: Post by jrham12 »

marinewonder wrote:
Has anyone dealt with this issue by choosing specific materials of the knockbox, is stainless steel better perhaps?
I have one of the Joe Frex stainless steel drawer-style knockboxes and it still gets some mold in it if I go past 3 or 4 days without emptying it. When that happens I dump it in the outdoor trash and give it a good spray down with the garden hose and dry it off with a few paper towels. Every other weekend or so I'll give it a good wash with dish soap for good measure.

But no, Stainless steel will not prevent the mold from forming...

Josh

jpender

#8: Post by jpender »

It's the coffee that the mold feeds on, not the container.

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TomC
Team HB

#9: Post by TomC »

Yeah, container materials or linings aren't going to help, if the room is humid enough, they'll grow. I'm washing mine out once a week, but mainly because my espresso consumption is fairly low.

I guess what OP is faced with is the decision whether he'd prefer to empty and clean it every 3 days, or spray diluted bleach/water into the container, then deal with the downsides of that (smell), and still need to clean it out, maybe saving a day or two?

When I visit my hometown in Los Angeles, the high desert of Antelope Valley, this obviously is never a problem. At home in Pacifica, it's ongoing. I also spur myself and my wife on to clean it out more frequently by tossing small bits of trash like the cut off tops of coffee bags in there, since I'm standing right in front of it anyway. Mine never gets more than 1/3 full at most, before it needs to be dumped and washed.
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bronsht

#10: Post by bronsht »

I have a thrown together wood knockbox. I only drink two espressos each morning. I empty the box every day as the box is very small. With San Francisco humidity it just makes sense to get rid of the grounds this way.