A couple of Qs about MJ yeasts

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jceg316

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I'm gonna be using mostly dry yeast from now on (long story) but it's been a while since I used any Mangrove Jacks yeast, probably years now.

The instructions say to sprinkle directly into wort, I've always rehydrated dried yeast the safale way: 10 times its weight in water and on a stirplate for 30 mins prior to pitching. Is there a benefit for doing this with MJ or is it still recommended to rehydrate?

Saflager yeasts require 2 sachets per ~23 litre brew (1 sachet per 10 litres), the Bavarian lager yeasts have the same pitching instructions as the ale yeasts, but would 2 be better anyway? I think the MJ Bohemian lager yeast suggests 2 sachets per 20 litres.

TIA!
 
I do at least two packs with the ale as well. You can slide by with one but it's easier on the yeast with two.
I've never rehydrated and I get fast-starting and strong ferments. I also see no problem with rehydrating the yeast. I'm already pleased with the dry such as MJ but who knows, maybe it would do even better rehydrated.
 
I always re-hydrate but can't say there was any benefit with the ones I've tried, quite a lag in starting and very long tail-off at the end with the 3 different ones I've tried. Bottling at the 3-week point was too early in all 3 cases, but that may have been down to fermentation temp (19C).
 
In contrast with darrelm here above, I always get faster fermentation when I rehydrate them. And I have used M76, M20, M41, M21, M84, M15, M29, M42 and M44.

Faster fermentation for me means, pitch in the evening at around 22:00, get a kraüsen between 8:00 and 12:00 next day.

For lager, indeed, double the amount of yeast you would use for top-fermenting beer.
 
Thanks for your replies.

@darrellm when that happens to me it's usually down to underpitching or not aerating. Did the beers taste alright?
 
Until something comes out better than this I'm rehydrating.
https://bkyeast.wordpress.com/2013/03/13/more-on-yeast-rehydration/
And yeast manufacturers who are starting to say you don't need to hydrate certain yeasts any more - show me something like that. Show me the bodies.
Thanks for the link, it's an interesting read. It seems rehydration is a huge benefit even if the supplier says otherwise? I guess from MJs point of view the easier it is to brew the more people will.
 
I'm too lazy to rehydrate. If you're too tight to buy a second pack of boho lager yeast, you can make a starter with dry yeast. I've done it few times and it works well
 
I'm too lazy to rehydrate. If you're too tight to buy a second pack of boho lager yeast, you can make a starter with dry yeast. I've done it few times and it works well
Something I was considering, because I really like W-34/70, was the brew before a lager make an extra 4 litres or so, ferment in a small demi with one pack of lager yeast and build up a "starter" that way. Depends if I can get organised on time. My next 2 brews are a black IPA and a Belgian stout so I don't need to worry about this right now, and I'll probably be brewing them in the new year.
 
Wow. What a faff. Ten times its weight in water and half hour stir plate. Really??

Never rehydrated yet in a home brew career that started in 1981. Never had a failure or off tastes either. Guess I'm just lucky.......
 
I'm gonna be using mostly dry yeast from now on (long story) but it's been a while since I used any Mangrove Jacks yeast, probably years now.

The instructions say to sprinkle directly into wort, I've always rehydrated dried yeast the safale way: 10 times its weight in water and on a stirplate for 30 mins prior to pitching. Is there a benefit for doing this with MJ or is it still recommended to rehydrate?

Saflager yeasts require 2 sachets per ~23 litre brew (1 sachet per 10 litres), the Bavarian lager yeasts have the same pitching instructions as the ale yeasts, but would 2 be better anyway? I think the MJ Bohemian lager yeast suggests 2 sachets per 20 litres.

TIA!

MJ do recommend re-hydration and give instructions of 30-35c for non lager yeasts. although on the packet this is not mentioned.

https://cdn.shopify.com/s/files/1/0195/8620/files/72539_V6_MJ_CS_YEAST_Bk_WEB.pdf?23
 
There's no harm in rehydrating so I'll so that anyway. It's also not as much as a faff as it sounds, probably takes longer to type out the instructions than to chuck on a stirplate.

Perhaps this is a question for a different thread, but does MJ have an equivalent for WLP005? I really liked that as an English ale yeast for stouts, porters and best bitters.
 
In his book Yeast, a practical guide to beer fermentation, Chris White of Whitelabs suggests that rehydrating dry yeast gives twice the number of viable yeast cells on pitching.
Meg, on the other hand, is still the best drummer in the world.
 
A lot of the dried yeasts now recommend no aeration or oxygenation with the dried yeast as they come with ergosterol's up to you if you re hydrate it isn't just the Lesaffre group but I believe Lallemand do the same CN 36 recommends re hydrate but not to aerate. Depends where MJ got their yeast from for rebadging .
 
A lot of the dried yeasts now recommend no aeration or oxygenation with the dried yeast as they come with ergosterol's up to you if you re hydrate it isn't just the Lesaffre group but I believe Lallemand do the same CN 36 recommends re hydrate but not to aerate. Depends where MJ got their yeast from for rebadging .
That's interesting. Hadn't heard of ergosterols. Will have to look it up. MJ and Fermentis say to pitch direct on the sachet and then suggest rehydration (for more professional results!) on their websites, if I remember right, and I don't recall any reference to aeration.
 
Always rehydrate dry yeast.

I did a brew day with a professional brew once.
He said 'Always rehydrate. It's easy and doesn't add anytime to your brew day.'

Since then I have rehydrated dried yeast form Mangrove Jacks & Fermentis.
 

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