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The plan was to make a sour saison that was tart and full of blackberry flavour. What I made was a very sour kick to the knacker bollocks saison that was full of blackberry flavour. I’m well pleased with this even if it makes most peoples eyes implode.

12 bottles worth were bulk aged but this was hurredly bottled so some sediment is visible.

If you are reading this after Armageddon then please take note that it was written in a simpler time under lock down during Covid 19. I’m saying this because like a lot of Walthamstows glitterati I started making sour dough. I was off work, dogging was banned and I needed a hobby…. aaaaanyway…

Previous to this I have only made one sour beer and that was using keffir grains as the souring agent. It was bit of a pain in the arse though produced a nice mildly soured sloe saison with the knowledge and kit I had. Since then I have wanted to get a good reliable souring agent that was easily to hand rather than use expensive commercial lactobiscillus cultures that need refrigeration to keep and a good bank balance to buy regularly… which I don’t. Using sour dough seemed like a good idea as it seems happy at room temperatures and I have a happy culture that sits on my shelves. It is fed on spelt or rye flour when ever I can be bothered to make a loaf and it really does the job souring the bread.

This monstrocity is the pellicle that formed after two weeks of the blackberries fermenting and souring. Yummy!

There are many views on how to sour a beer and I will leave that to people smarterer and more eloquent that what me is. Amongst the myriad of methods you can either sour then boil the wort or boil then sour the wort. I decided to boil as usual then sour afterwards as I wanted the starter to be able to interact with the yeast and hopefully create a more complex beer than kettle souring which happens preboil.

Hitting the acid and sacch rest bang on target

I wanted a very sour beer and to create an ideal wort I used both an acid rest in the mash and acid malt. The mash started with the 45°C ferulic acid rest then my usual 63°C Saccharification rest then it had an extra 60 minutes at the same temperature when the acid malt was added. Acid malt can inhibit sacchrification if initially added so it needed this extra step to bring pH down to give the souring bacteria a good head start as well as enough sugar to be in the wort to ferment.

Once I had boiled the wort for 30 minutes without any hops it was then cooled to 30°C and had the sourdough starter added. The sourdough starter was prepared a day earlier using a sterilised jar to minimise any contamination. 50g of the regular starter was dropped into a jar then had 50ml boiled and cooled water and 50g of flour added. This then sat overnight to get happy and vigorously souring. This is the same method with some precautionary sanitising as I use to make a big loaf and as I know it works I was happy to apply it to the beer to get a large colony of bacteria.

L to R Sourdough starter, added to the wort, mixed into the wort.

The wort complete with starter was then poured into a demijohn so that it could be in airtight conditions to sour with out any hint of oxidation. Sitting in my hot kitchen that had daytime temperatures around 25 to 27°C it started within a few hours and by the next morning the airlock was happily burping. Sourdough starters are a mix of bacteria and yeast so this could be either from a heterofermative lactobiscillus strain producing carbon dioxide and/or yeast. I have no way of knowing and all I know is that it was happy and both smelled and tasted not only sour but good after two and half days. In future I may push this longer and also measure the drop in acidity – for now it was just left to do its thing. After this it was added to the remains of an existing beer that had just been racked away onto some fruit.

Post souring but pre blackberries. A slight haze appeared on the soured saison from the souring bacteria.

I chose to put this onto the remains of the existing beer for a number of reasons. One is cost – I have used an inexpensive souring agent and now I get to recycle some yeast. Being honest it was not the monetary value I was interested to but doing as much of the work as possible with ingredients available at anytime. As well as cost the yeast was also extremely happy and potent having gone from the small vial for the initial beers inoculation to a full sludgy cake at the bottom of the fermentation bucket. It was there sitting happy and ready for a new beer to ferment. It also meant I could “reuse” the existing hops in the remains of the beer but also have a soured beer too. Hops generally inhibit lactobiscillus but combining them now meant I could have a reasonable hop profile to about 7 IBU and have a decently soured beer with out the hops interfering and probably aiding the creation of more complexity.

The intact blackberries sanitising with campden to kill any wild yeast and bacteria.

The blackberries were combined at the same time. They had sat for 8 hours in a minimum of water with campden added to inhibit wild yeast and any bad bacteria on the skins. After the water was drained away the berries were smushed by my clean sanitised hands and and poured into the fermenter.

Hideous wort makes amazing beer.

Over the next few hours the sealed lid of the brew bucket swelled with an extremely vigorous fermentation within. After 24 hours the blackberry content had become more visible through the opaque brew bucket sides, turning from a very pale to bright pink as juice was liberated from the berry flesh and circulated in the beer.

BLACKBERRY SOURDOUGH SAISON RECIPE

Batch:14L (including the 2litres of previous beer)

Start gravity:1.07 (plus fruit addition)

End gravity: Probably about 1.00.

ABV: 7% from the grain, probably 8% with the blackberries.

IBU: 7 (estimated)

Colour: 4 SRM before the fruit addition

Water profile: Thames tap moved towards a lighter beer profile.

GRAIN BILL

Malt Weight Percentage (Per litre) German Pilsner 2.8kg 75.9 233g Acid Malt 360g 9.8 30g Vienna 330g 8.8 27g Munich 150g 4.4 12g Caramunich 50g 1.5 4g

EXTRA FERMENTABLES

Fermentable Wright Percentage (Per litre) Blackberries 1.1kg N/A 92g

MASH

45°c for 60 minutes for Ferulic Acid rest

63°c for 60 minutes Sachrification rest

63°c for 60 minutes Acidification rest

1litre of water to every 500g of grain. Vorlaufed until the wort runs clear. Sparged with water at 63°C to bring it to volume of 12L before the boil.

BOIL

No hops on a 30 minute boil

FERMENTATION

Sour-dough starter made with 50g base starter, 50g sterilised water and 50g spelt flour. Allowed to get to a vigorous fermentation in a jar before being added to the 30°c cooled wort after the boil. This was allowed to sour in a sanitised and closed demijohn for two and a half days until it was to may taste.

Poured onto 2 litres of left over wort form a previous brew that used the same basic grain bill and was mildly hopped. The WLP4021 Saison II yeast was already active in a healthy colony so the soured wort was not aerated except ambiently when poured in. Sanitised and crushed blackberries added at the same time.

Temperature was allowed to free ride straight up to 28°c using a fermentation jacket to help. Fermentation was very very active but kept in the sealed bucket to allow the blackberries to infuse for 10 days so no observation or measurements taken to minimise the chance of oxidation.

Bottled after three weeks in secondary that allowed sediments to settle. Low to moderate carbonation in bottle.

Any ideas or advice always accepted (as long as you are nice!)