Different results with flip-top bottles and bottle caps

[Zoltan]

I made a batch of ale and bottled it with two kinds of bottles--capped Sierra Nevada bottles, and Grolsch-style swing-cap bottles. The beer in the capped bottles is pale (I used pilsner malt), clear, and nicely carbonated, while the beer in the swing-cap bottles is darker, murky, and rather flat. The obvious conclusion is that swing-cap bottles aren't making a good seal, but they're new, and the spring seems tight. I also don't know why that would change the color of the beer. Any ideas?

 

[ba-brewer]

Oxidation will darken the beer, sounds like your swing tops are not giving a good seal. Not sure about the murky part.

edit: Any chance the seal washers are silicone?

 

[MaxStout]

Maybe there was some mold under the rubber seals and it spread into the beer?

Those rubber seals harden over time and can leak, which might explain the flat beer. Replace them from time to time.

 

[Drewch]

How old were the rubber grommets on the swing-tops?

 

[micraftbeer]

Keeping in mind that "bought new from the store" doesn't mean these weren't sitting on their floor inventory for a couple years...

 

[Deadalus]

What was nww, the bottles, the gaskets, or both? What color are the swing tops?

All my bottles get a quick rinse them go in a bucket. When the bucket is full I fill the bottles and bucket with water and dawn. If any have labels I add ammonia and let them sit until I feel like scrubbing them. I take the gaskets off the flip-tops. I use a bottle brush on all but I hit the ceramic tops with a toothbrush. I boil the caps and gaskets when bottling. I starsan the bottles and make sure to dip the ceramic top in the bowl. I have one of those spring loaded sprayers that sit on a bottle tree.

If all the flip-tops are new and off-flavor however, sounds like something may be wrong with the gasket material or you didn't clean and sanitize correctly.

I store mine clean with the gaskets off but the top is closed.

 

[Unicorn_Platypus]

Make sure you aren't using silcone gaskets

Unfortunately most new flip bottles nowadays come with terrible seals that are highly permeable to oxygen

Buy these ones for morebeer, you will get a great seal and the material has a much better oxygen barrier than the normal silicone ones

I contacted morebeer and the said the material of these gaskets is TPE (thermoplastic elastomer)

While they weren't able to provide fact sheets on the permeability, the googling I've done on the material leads me to believe its much better tha than silicone

https://www.morebeer.com/products/r...IOPdqmhcVo-9SUsts01UBdVfwcg0B3wRoClDEQAvD_BwE
The material matters just as much as the quality of the seal. Silicone can seal well, but oxygen can still creep in through the pores in the material

If I were to guess you probably have a bad seal and bad material