Among the swag handed out during the 2013 Beer Bloggers Conference in Boston, the Hydro Flask growler took top prize.  Hydro Flask, based in Bend, OR, provided each of us a 64 oz insulated growler to take home and enjoy.  I’ve coveted one of these for quite a while and was thrilled to get my hands on it.

Hydro Flask claims their double wall vacuum insulation technology will keep your cold liquids chilled (and carbonated) for up to 24 hours, or your hot liquids steaming hot for 12 hours. They are cast from double wall vacuum insulated food grade 18/8 stainless steel, BPA-Free and resistant to bacteria and odors.

Hydro Flask also donates 5% of the gross profits on each bottle to a charity of your choice (from their varied list), an offer they extended even to us based on retail value.  I directed my 5% to the Red Cross.

Hydro Flask growlers are pricey, particularly compared to your typical amber colored glass growler.  So I wondered, if you’re going to shell out $45 to $49, the average retail price online, does it live up to the hype?

Only one way to find out:  devise some tests and grab some beer.  I picked four simulated real-life tests to see if Hydro Flask was worth the investment.  Read on to see how it did.

Test One: Five Hour Room Temperature.

The test:  Filled growler left out at room temperature for five hours.

Why:  For those times when you grab a growler to take to a friend’s house to watch the game or enjoy a party.  The growler gets left out while you’re enjoying some other offerings. This test primarily tests temperature rise.

The process:  I had the Hydro Flask filled at Missoula’s Draught Works Brewery with their That’s What She Said Cream Ale (5.7 % abv, good amount of carbonation, very tasty). It’s a beer I enjoy and have had enough to be able to gauge the freshness and the carbonation. The temperature of the beer after filling was 37 degrees, which I measured using a probe connected to an electronic thermometer.  After a 15 minute ride home in the truck, I set the Hydro Flask on the counter, out of direct sunlight, at room temperature which averaged around 72 degrees.  After five hours, I opened up the Hydro Flask and measured the temperature.

The result:  The temperature had risen to 41 degrees, an increase of only four degrees and a very respectable result.  I poured a pint to check carbonation level and taste.  There was no detectable decrease in carbonation and the beer tasted as good as always.  The temperature suited my tastes just fine.

Test Two: Twelve Hour Room Temperature.

The test:  Same test as before, but left out at room temperature for twelve hours.

Why: I know you wouldn’t do this to a growler unless you’re particularly forgetful or are hiding it under your desk at work, but I thought it would be good to push the parameters. After all, Hydro Flask claims it will keep your liquids chilled and carbonated for up to 24 hours. This one tests temperature rise and carbonation level along with freshness and flavor.

The process: I again filled the growler at Draught Works Brewery with their Cream Ale. The temperature of the beer after filling was 38 degrees. After a 15 minute ride home, I left the Hydro Flask out on the counter, out of direct sunlight.  The room temperature was a little warmer this time, averaging around 76 degrees. After twelve hours, I opened the Hydro Flask and measured the temperature.

The result: The temperature of the beer was 47 degrees, a rise of 9 degrees.  Since it was 5:45 a.m. when I checked it (there’s dedication) I did not pour a glass and check the carbonation level.  There appeared to be plenty of carbonation based on the foam rising up and over the top of the growler.  Instead, I stuck the Hydro Flask into my beer fridge (which hangs out at around 43 degrees) for another twelve hours.  By then, the temperature had dropped one degree to 46.  I poured a full pint and checked it out.  No detectable decrease in carbonation level.  The beer still tasted fresh with plenty of carbonation.  I had no issue with the temperature. I generally prefer my beer to be in the 40 – 45 or so degree range.

Test Three: Forty-Eight Hours in the Fridge

The test: Filled growler, left in the fridge for 48 hours.

Why: Because sometimes you fill more growlers than you can drink. Sometimes you stock up for a holiday weekend when the brewery is closed.  This one tests carbonation and flavor/freshness for those times when you need to store your growler for a bit.

The process: Keeping things consistent, I filled the Hydro Flask at Draught Works Brewery with the Cream Ale. The temperature of the beer after filling was 37 degrees. After a 15 minute ride home, I put the Hydro Flask in the beer fridge.  The temperature in the fridge was 43 degrees (there is only beer in there, no food).  After 53.5 hours, I opened the Hydro Flask and measured the temperature.

The result: Yes, this was intended to be a 48 hour test, but due to the schedules of daily life, that got extended by 5.5 hours.  After 53.5 hours, the beer was 43 degrees, matching the temperature in of the beer fridge.  No carbonation was rising to the top upon opening, unlike previous tests.  I poured the beer into a pint glass and was able to generate a good head, but less than previous tests.  The taste was still fresh, but there was noticeably less carbonation.  I’d go so far as to say the beer was “fine,” but it lacked the crisp carbonation of a normal Draught Works Cream Ale.

It must be noted, however, that Hydro Flask makes no claim it’s growler will keep beer carbonated for 48 hours. Thus, while the growler did not ace the 48-hour fridge test, the beer was still quite drinkable. I would not rely upon it to maintain beer in a perfect condition for two days, but its nice to know I’ll still have some pretty good beer if need be.

Test Four: Two Hours in a Vehicle on a Sunny Summer Day

The test: Filled growler, left in a vehicle with the windows rolled up on a hot summer day.

Why: Because you’re an idiot.  You grabbed your list of errands and stopped by the brewery to fill your growler to share with your significant other once you’re done.  You head to the next stop and lose track of time.  Before you can utter the words “bitter beer face,” you remember your foolish error and race back to your vehicle.  This one tests whether you’ll still be welcome back at home.

The process: Consistency is important in these endeavors. I again filled the growler at Draught Works Brewery with their Cream Ale. The temperature of the beer after filling was 37 degrees.  I left it in the truck, closed the windows and let the growler sit in the sun shining through the lightly tinted windows.  The temperature in the truck at the start of the test was 84 degrees.  The outside temperature was 82.   Two hours later, the outside temperature was 92 degrees.  The growler caught a bit of a break as some high clouds moved in and softened the brunt of the summer sun, but the inside of the truck had risen to a toasty 125 degrees.  I then opened the Hydro Flask and checked the temperature of the beer.

The result: You can go home and pretend nothing ever happened. The temperature of the beer was 40 degrees, a rise of only 3 degrees.  There was no detectable decrease in carbonation level and the beer still tasted fresh.  Consider yourself lucky.  The Hydro Flask bailed you out, but you really should be more careful with your beer.

In between the four tests I also found myself in Helena, MT, at Blackfoot River Brewing Co. and had the Hydro Flask filled with their most excellent North Fork Organic Porter. After a two hour car ride back to Missoula I stuck the growler in the beer fridge. Twenty four hours after it was filled we cracked it open and poured a pint. It was fresh and well-carbonated.

Being stainless steel, the Hydro Flask is easy to clean, especially if you rinse it out before anything dries.  In that regard it does not have an advantage over glass, which, like the stainless steel, is free from retaining odors. However, the Hydro Flask excels over glass by being impervious to light and it’s obvious insulating benefit.

My only complaint is that the initial pour from a full growler is a little difficult to pull off, especially one handed.  It’s a minor nitpick that you can overcome with the help of a friend. Hey, it’s a full growler. You’re probably not going to be lacking in offers for help.

These tests were all performed with a full growler.  No growler will maintain a good carbonation level if it is not full.  Once you take that first pint off the top, you’ll want to share the rest with friends, or get crackin’.  Plus, all bets are off if your bartender is not adept at filling growlers.

Hydro Flask makes double walled vacuum insulated water bottles in a variety of sizes and shapes and all come with a lifetime guarantee.  I can vouch for the quality of 64 oz growler.  It is definitely Growler Fills tested and recommended.