Tastes a bit like vinegar and cider

[Deevotronics]

So my first all grain brew in a Brauduino (props to lael and matho) was a roaring success, used the Pilsner recipie from the Spiedel site and ended up with a great batch. My second run, however, tastes quiet sour and has no head. Followed the same steps but the result was significantly different. Can anybody shed light on what makes a beer sour and lack bubbles? I am new to brewing and jumped straight into the deep end, was simply intruiged by the braumeister concept.

 

[TimT]

Probably a bacteria.

 

[manticle]

Sourness can indicate infection. Green apple can indicate beer that has been removed from yeast too early, insufficient or unhealthy yeast or oxidation.

Sour vinegar suggests acetobacter infection - noticed any fruit flies about the place? Other sour infections include lactic- whereabouts are you cracking grain? Near your fermenters?

 

[TimT]

I think we'd need more info about your process - for instance, did you notice anything odd or unusual about the second beer while it was fermenting? Lack of action in the airlock, strange growth on the surface of the beer, lack of ordinary krausen (froth/foam that forms on the top of a beer about one to two days into fermentation), etc etc. These might indicate an infection.

 

[QldKev]

Sour and has no head is infection. Sour from the infection, and no head as the infection attenuates a lot better than normal yeast leaving no body in the beer.

 

[Deevotronics]

I purchase my grain pre-crushed from Grain and Grape in Williamstown. Seems there is a mix of green apple and vinegar notes. Admittedly I had a few drinks while making the brew, so attention to detail was not as paramount as it should have been. The first batch I thoroughly boiled some water then cooled it before pitching the yeast, second batch I pitched directly into the fermenter then used the flow of wort to dissolve it as this was recommended to me. Razz mentioned it may have been improperly cleaned fermenter. The tap is a single piece plastic number and I couldnt get all the gunk out of it, however I did wash everything in a phosphoric acid solution while the wort was boiling so I figured that would have killed all the nasties. There certainly wasnt as much action in the airlock, and when I opened it up to remove my hydrometer prior to bottling I noticed so chunky yellow clumps floating around on the surface and little to no foam had formed during fermentation. All things seem to point to poor yeast cultivation or secondary bacteria.