Dry hopping issues

[Geoff Logan]

I'm having an issue with dry hopping as of late. It seems that every time I dry hop, the lab comes back with growth on the plates. I need some advice. Here's my procedure.
1.) Reach TG and crash.
2.) Harvest yeast (as to not have too much suspended solids).
3.) Dry hop with stainless funnel clamped to PRV. (I empty two new 11# bags of hops directly into the funnel. Remove funnel, spray with alcohol and replace PRV).

I talked to Dave @ BSI and Matt B. of Firestone and both seem to not be as concerned with the "growth" because most of it (if not all) won't spoil product. Am I paranoid here?

Any advice? Thanks in advance.

Geoff

[dick murton]

Of course you will have "infection". The hops used for dry hopping are not sterile and will be crawling with yeast, bacteria etc which will be growing on the leaves / strig etc. This is in spite of them being "kilned" normally. However, hop resins are a pretty good bacteriocide and do not normally let much grow on the actual hops, or cause infection from the bugs on the hops

Now the handlers hands or what ever is being used to put the hops into the cask / FV are a totally different matter

However, in my experience, I have never heard of infection sufficient to cause problems from the hops.

Which means of course someone will shout out about .........

Keep the hops in cold storage in sealed containers / bags between delivery and actual use and you are unlikely to have problems

[rudge75]

Dick's answer kind of begs the question:
How do you store your hops?

If your hops are stored in a cooler with constantly changing humidities? Do you have them in a walk-in cooler where you're washing tanks, spilling beer, etc.?

or

Are they kept unopened in your cooler then moved to a deep freezer when open?

[Roger Greene]

Have you identified what is growing?

[Geoff Logan]

Rudge: I store my hops in the cold room @ 34 degrees unopened. Then use the entire package through a sanitized stainless funnel through the sanitized PRV.

Roger: As far as we can identify with our microscope and staining methods we can identify bacillus. Whether it's lactobacillus or a more benign, fast-growing bacillus is still in the air (no pun intended).

We plate with on an agar, then if there is any growth we go to HLP. This isn't the fastest process but it helps me sleep better. I haven't ever had any sour beer but growth is always disconcerting.

[MJMurphy]

In from the fields....

The hops will be carriers of all sorts of fun microbes. Pellets may pose less of a source than whole-leaf due to the pelletizing process, but they still carry plenty a decent population.

You will likely see a variety of wild yeast, molds and bacteria, many of which are aerobic and may have limited to no impact on the quality/flavor of the beer. The

The point at which you are adding the hops, after fermentation is complete, or very nearly complete, the pH and alcohol will be conducive in limiting the ability of the hop-borne microbes to establish themselves. The hops may have the additional benefit of providing some additional resistance to lactic-acid bacteria (Sensitivity of lactic acid bacteria to hop acids, http://www.scientificsocieties.org/j...99_5_405.pdf ).

While the hops may present their own potential, the method of addition can pose its own threats. About all that can be done is to minimize the chance of contamination.

[shortz]

differentiate

you should be able to differentiate between lactobacillus and bacillus with your micro and catalase test with KOH (Potassium HYdroxide). also, to add, the temp will be difficult for substantial microbial growth.

[dberg]

Are you growing anaerobic or aerobic on your plates? Why not just use HLP to start, as it's going to catch the two biggest beer spoilers?

[Geoff Logan]

Thanks for the advice fellas!

dberg: We are growing aerobically right now. I used to use the candle in a bucket trick to grow in a pseudo-anaerobic environment, but have since stopped that practice. Anyway, I'm thinking HLP is definitely the way to go here.