Raspberry Sour advice - keg or secondary ferment?

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mtb

Beer Bod
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So I got a bit sour-heavy over the past few months and put down a double batch of 50/50 Pilsener and Wheat malt. Hit my target OG of 1.042, boiled, lacto kettle soured, pH of 3.2 after 72hrs and almost sour enough to vaporise my tooth enamel. Boiled again to kill lacto. Happy days.

In one fermenter (20L) I pitched US-05 and fermented out to 1.01, then added 3.5kg of raspberries. They were frozen, then thawed and pulverised before adding. The FG didn't change much - 1.01 - which isn't too surprising since online calculators tell me that amount of raspberries would've upped the gravity by just a couple points, so it fermented right back out within a day or so.

  • The taste is on point.. I mean, I wanted raspberry, and it's a huge hit of raspberry. Should've expected as much with 3.5kg.
  • The sourness is on point. Hits the back of the tongue after the raspberry, coats the mouth.
  • It's the mouthfeel & consistency I'm worried about. It's thick. Pouring from a hydrometer into a glass showed it to flow with almost.. syrupy texture, but gravity reading is 1.01. Should I dry it out by adding some dextrose and doing a secondary fermentation? Should I rack off the raspberries prior to doing so? Or should I just keg & carbonate as per usual?
It's intended to be a summer chugger alongside the beers, something for the ladies as well as the men, a general crowd pleaser, something to shut up my damn in-laws who somehow have a genetic predisposition to beer-hate. Heathens.
 
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dunno about that man. maybe it's some pectin or something in the fruit that caused it to set a bit. did you use too much gelatin? a beer like that should be crisp as drill Sargent's bed sheets.

Beware the raspberry flavour fades quick quickly. drink fresh!
 
dunno about that man. maybe it's some pectin or something in the fruit that caused it to set a bit. did you use too much gelatin? a beer like that should be crisp as drill Sargent's bed sheets.

Beware the raspberry flavour fades quick quickly. drink fresh!
Since it tastes like raspberry cordial.. I'd say it'll go mighty quick with the wife and her sister in the house :D

Pectin is a possibility, hadn't thought of that. I haven't yet used finings
 
yeah that is a f load of raspberries. This is the one I did not too long ago. I used the coles brand frozen raspberries. It was like raspberry softdrink without the sweetness for the first week. I added 2ml bio pectanase which was the advise from Anthony at craftbrewer and fined with biofine clear. It was absolutely crystal clear with a real fizzy refreshing mouthfeel. The recipe seems a lot like yours. mash and sparge water ph was both 5.2. mashed at 62.

Ingredients:
------------
Amt Name Type # %/IBU
23.00 l Distilled Water Water 1 -
5.00 ml Lactic Acid (Mash 60.0 mins) Water Agent 2 -
2.30 kg Pilsner (2 Row) Bel (3.0 EBC) Grain 3 50.0 %
2.30 kg Wheat Malt (Barrett Burston) (3.2 EBC) Grain 4 50.0 %
3.00 g Hallertau Magnum [13.80 %] - Boil 60.0 m Hop 5 4.3 IBUs
1.0 pkg Safale American (DCL/Fermentis #US-05) Yeast 6 -
2.00 kg Frozen Raspberry Flavor 7 -
 
Practically identical to mine - I threw in a few gm of magnum too. I held off on the lactic acid in case the lacto was sufficient, but I might throw some in anyway. Did your perception of sourness increase with carbonation?

I'll see if I can find some of that pectanase, it sounds like a good idea. Thanks for pointing me in the right direction mate.
 
I held off on the lactic acid in case the lacto was sufficient, but I might throw some in anyway.

The addition of lactic acid is not primarily to contribute to tartness. You add it in the mash so that the starting ph of the wort is a little lower than normal in order to inhibit anything else growing while the lacto does its thing. For non kettle soured beers you rely the immediate pitching of yeast to stop anything else from getting a foothold.

This could explain the unusual pellicle that I got on my last kettle sour when I forgot to add lactic acid to the mash. Picture below. Fortunately the sour turned out great despite this.

full
 
I put 2.5kg into 23l of berlinner and it was too much I reckon. I suspect after a year or so the few i bottled might be just right but most of it never lasts that long.

Oh they went in the primary after a week and it turned out pretty good.
 
This is a great thread, I really want to do a raspberry sour but haven't worked up the courage yet (and I don't have a pH meter either).. learning a few things though, hopefully your sour turns out great mtb!
 
The addition of lactic acid is not primarily to contribute to tartness. You add it in the mash so that the starting ph of the wort is a little lower than normal in order to inhibit anything else growing while the lacto does its thing. For non kettle soured beers you rely the immediate pitching of yeast to stop anything else from getting a foothold
That makes a lot more sense. I was pretty cautious about contamination, I boiled post-mash for 15min, cooled to 40C, in went the lacto bugs, glad wrapped the kettle opening, purged headspace with CO2, and chucked the lid on to seal the glad wrap. I was pretty worried after the souring period because it had an ever so slight aroma of vomit - ie butyric acid. Thankfully that boiled right off.
I put 2.5kg into 23l of berlinner and it was too much I reckon. I suspect after a year or so the few i bottled might be just right but most of it never lasts that long.
I'll definitely tone down the fruit additions in the next batch.. I can always add more, can't take 'em out as easily. Grabbed a cheap chest freezer off Gumtree for stocking up on fruit for all-year sour making..
This is a great thread, I really want to do a raspberry sour but haven't worked up the courage yet (and I don't have a pH meter either).. learning a few things though, hopefully your sour turns out great mtb!
Thanks mate. At minimum it'll be a 4.5% ABV fire engine with real fruit! Get on the souring bandwagon, go for gold. Essential Nutrients IBS Support pills are a cheap go-to for lactobacillus plantarum; just one capsule contains 20B cells (ie enough to innoculate a batch). I dropped my pH meter on my concrete floor a couple weeks ago so now I feel your pain.. so does my wallet.. :mad:
 
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It actually sounds like it could be ropy, pouring thick like that is a bit of a give away. Milk the funk has an ok write up on it. Might go away after awhile, by which point the raspberry will have probably dropped out.

Pretty hight starting and finishing gravities for a berliner, you want it around 3.5% with a FG under 1.006. I don't think it's an overly excessive addition of fruit, maybe not in a beer that's already 3.2pH though!
 

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