Brewing Bad - Common mistakes made by homebrewers video guide

[David Heath]

It is time for a new series of videos that look at common mistakes made by homebrewers all the way through the process from grain to glass.
As a huge fan of the TV series Breaking Bad, I have given this one a tribute name and image.
You will find a lot of information presented within this first part and future parts covering a variety of different topics which I hope act as a checklist that is both helpful and reassuring.
As usual,thank you for all your kind support and enthusiasm for my channel.
Please keep your questions, feedback and requests coming but please give me some time to answer, I get a lot of messages and answer them in the order they were sent in, particularly those on Facebook messenger tend to stack up! If you are comfortable then please ask questions within Facebook groups, forums or Youtube, so that others can also either benefit or contribute.
Happy brewing!

 

[McMullan]

Dry hopping with hops straight from the freezer can cause a temperature shift that affects yeast? So put hops in the fridge for a day or two before dry hopping? Really? Hops have a moisture content <10%. They don't actually freeze. How are they going to cause a shift in temperature, exactly?

 

[An Ankoù]

I liked the warning about cheap all-in-one systems and converted tea-urns. Never used either, but I'm sure there are some dodgy ones around. Not too sure about the mashing in technique. Mashing in is an art form and a balance between getting the strike temperature right and getting the mash homogeneous as quickly as possible. Stepped mashes depend on whether you're using a tea urn or an insulated mash tun. Never used the former. Keeping hops in the freezer? Never done that. The fridge is good enough. Open bags of pelleted hops, ok. Massive temperature fluctuations upsetting the yeast, yes. Gradual changes in temperature which will cause very slow changes in a large body of liquid undergoing an already exothermic process, I don't think so. Each to his own! Sanitation, dechlorination, perhaps water chemistry, mash end point, a decent boil, using a hydrometer, sanitation, sanitation and sanitation. Are what I would have liked to see when I was a newcomer to the subject.

 

[David Heath]

Dry hopping with hops straight from the freezer can cause a temperature shift that affects yeast? So put hops in the fridge for a day or two before dry hopping? Really? Hops have a moisture content <10%. The don't actually freeze. How are they going to cause a shift in temperature, exactly?

If the amount added is small then this will not have an effect but these days people are using large amounts of dry hops and often this will reduce the temperature if used straight from the freezer. I have had experience of this and others have mentioned it in questions they have.

 

[David Heath]

I liked the warning about cheap all-in-one systems and converted tea-urns. Never used either, but I'm sure there are some dodgy ones around. Not too sure about the mashing in technique. Mashing in is an art form and a balance between getting the strike temperature right and getting the mash homogeneous as quickly as possible. Stepped mashes depend on whether you're using a tea urn or an insulated mash tun. Never used the former. Keeping hops in the freezer? Never done that. The fridge is good enough. Open bags of pelleted hops, ok. Massive temperature fluctuations upsetting the yeast, yes. Gradual changes in temperature which will cause very slow changes in a large body of liquid undergoing an already exothermic process, I don't think so. Each to his own! Sanitation, dechlorination, perhaps water chemistry, mash end point, a decent boil, using a hydrometer, sanitation, sanitation and sanitation. Are what I would have liked to see when I was a newcomer to the subject.

Thank you. I have more parts coming in this series that will gradually cover more.

 

[strange-steve]

His dry hops are measured in litres per gram.

 

[Session]

Do I have to repeat what I typed? How much are you adding, FFS?

David’s answer seems pretty reasonable to me. If you put something cold into something warmer it is going to reduce the temperature... I’m not sure where the confusion is?

I’ve certainly dry hopped with 200g hop pellets before and can see that this would be likely to reduce the temperature.
It’s not uncommon to dry hop at rates of up to 20g/L for some big American styles, and it’s probably useful for brewers not accustomed to thinking about temperature shifts to be aware of this. I thought it was a really helpful video, and whilst not all the points necessarily apply to me they are all good to be aware of.

 

[strange-steve]

If you put something cold into something warmer it is going to reduce the temperature... I’m not sure where the confusion is?

Yes but by how much? Applying a little physics you can work out that 200g of ice at -10° added to 20L of water at 20° would reduce the temperature by less than 1°. That's for ice which probably has a higher specific heat capacity than hops, so the change would be minimal.

 

[McMullan]

David’s answer seems pretty reasonable to me. If you put something cold into something warmer it is going to reduce the temperature... I’m not sure where the confusion is?

I'd say any confusion here seems to be due to David Heath erroneously overlooking the fact that hops don't freeze due to their low moisture content thereby act as very, very poor insulators. Once removed from a freezer and their packaging they soon feel at room temperate for some 'bizarre' reason

 

[Cwrw666]

I liked the warning about ... and converted tea-urns.

There are such things as thermometers.

 

[Session]

Yes but by how much? Applying a little physics you can work out that 200g of ice at -10° added to 20L of water at 20° would reduce the temperature by less than 1°. That's for ice which probably has a higher specific heat capacity than hops, so the change would be minimal.

Ah that makes sense - thanks! I hadn’t stopped to think about the numbers

 

[Session]

I'd say any confusion here seems to be due to David Heath erroneously overlooking the fact that hops don't freeze due to their low moisture content thereby act as very, very poor insulators. Once removed from a freezer and their packaging they soon feel at room temperate for some 'bizarre' reason

I use mine straight from the freezer so have never had them out long enough to notice this - good to know! I imagine whole cones would be even less capable of holding temperature than pellets, which is what I mainly use. Thanks!

 

[MmmBeer]

I'd say any confusion here seems to be due to David Heath erroneously overlooking the fact that hops don't freeze due to their low moisture content thereby act as very, very poor insulators. Once removed from a freezer and their packaging they soon feel at room temperate for some 'bizarre' reason

Interesting concept. I tried looking for a specific heat capacity for hops or similar plant matter, the closest I could find was for wood pulp or cellulose, which was approximately 1400 J/kgK or one third that of water. This would explain why hops from the freezer don't feel cold to the touch, especially leaf hops, (which are preferrred for dry hopping) because of the greater surface area.

Running the maths on the worst case example of adding 20g hops per litre, straight from the freezer at -18°C would lead to a bulk temperature change of 0.12°C in the beer, unlikely to be enough to cause thermal shock, especially as much of the yeast will be lying dormant by the time dry hopping occurs.

I don't think that I will start removing my hops from the freezer a day before dry hoppping, but it may be worth weighing them out five minutes earlier, while I remove the FV from the brew fridge and get the primings organised.

 

[darkbright]

David is a certified Materbrewer and former commercial brewer of 30 years experience, so maybe that impacts on his view on brewing practices and hop amounts.

 

[Gerryjo]

Got to give him respect for his time, effort, experience and the fact that these bad brewing practices in both videos so far will actually give benefit to a lot of brewers out there especially if just converting to AG but bar that it's across the board.
I'm glad that there are those out there that will take the time to make videos which are free for us to view and take it from it what we want as it is from his experience by himself and obviously interaction with other brewers.
I quite enjoyed them actually but doesn't mean I have to practice what I see and hear. It's a guide.
Keep up the good work @David Heath

 

[An Ankoù]

As for me, I don't know the guy and certainly hope my early comment hasn't offended. I simply found the advice in this "first video" a bit random and not "common" mistakes in my experience. Yes yeast temperature shock and grain crush size are important, but for many of us, we don't add 250 g of dry hops close to 0K to a 20
litre batch and many of us have little control over our grain crush size. When there are more obvious and common mistakes. That's all.

 

[An Ankoù]

Good.
Let's have video #2 then Dave and we'll love the bits we love and wrangle over the bits we can find to chew. Like we always do.

 

[MyQul]

I really like Davids vids. I think they're's things for novice brewers and more the experienced. I like that he keeps on topic and doesnt ramble all over the place across a number of topics. So I can just watch the ones I'm interested in knowing that I wont have to listen to stuff I'm not particularly interested in

 

[Gerryjo]

Good.
Let's have video #2 then Dave and we'll love the bits we love and wrangle over the bits we can find to chew. Like we always do.

 

[Sadfield]

I probably would have made this video number one of the series. Wash on, Rinse off Daniel-san.