IPA heat experiment

Depending on the amount of oxygen introduced during packaging the exposure to higher temperatures will indeed quickly negatively impact the flavor profile of hoppy beer.

One thing is certain: exposure to high temperatures does not benefit beer.

Cheers!

 

Your conclusions are probably sound, but ideally you would have had several crowlers to try since there is a slight risk that the way the crowlers were filled differed somehow. Certainly @JackHorzempa is correct, it surely is not good for beer to be heated like that.

 

Nice experiment, and thanks for the write-up. You didn't say it, so to clarify, were both beers equally chilled when you tasted them?

 

As has already been said, heat does beer no good, and this was a good experiment.

However, if a more scientific experiment is desired, I have a few suggestions.

First, try limit the variables to only heat.

You can get closer to this by using IPAs from more than one brewer packaged in automatic canning lines rather than only one beer from the same brewer in hand-canned crowlers.

While I recognize you were going for effect during shipping, I would still suggest not using crowlers or growlers, since neither are necessarily consistently filled.

Instead, use machine-packaged canned beer from brewers known to have good quality control over their canning process and that take care to reduce the amount of O2 in the can.

Second, have a couple different hoppy IPA from different brewers for your test.

You can double your sample size with pint cans rather than crowlers, and even having 3 beers in the heat and in the 'fridge is not out of the question for a couple of tasters.

 

Interesting experiment. You may wish to broaden your parameters however. My local beer truck drivers say interior temp is more like 120-125 degrees and can easily go higher if the vehicle sits for awhile.

Don't know about your local conditions but I've visited Missouri in the summer and it can get pretty warm there.

 

Also it would be better to use small bottles
big containers preserve beer better

 

I traded a few growlers of Societe ipas during the summer. The receiver mentioned that were all kinda dull and most people who drank them thought the heat had a negative effect on beer.

 

Flavor compounds in beer can be very sensitive to heat, it essentially speeds up the denaturing of these compounds (and then recombination). Different compounds break down at different rates, and I'm sure everyone here has experienced it.

Organic chemistry is crazy, especially in beer where there are so many compounds that change at different rates.

 

Nice write up.

It would be interesting to know the actual temperatures that are in the FedEx, UPS, etc. vehicles typically during the summer. There must be a lot of heat sensitive stuff sent. Lots of people get food via shipment from Amazon and similar services. Cold and fresh items have ice packs, but the regular pantry stuff doesn't.

I received some chocolate via FedEx last week and they were not melted in any way.

 

This was quantified by Nick J. Huige, Ph.D. in his technical article entitled: Chemical Engineering for Quality Brewing.

http://www.mbaa.com/publications/tq/tqPastIssues/2004/Abstracts/0105-01.htm

Unfortunately you need access to read the paper.

Within the paper is:

“Figure 4. Temperature of outside air and calculated average temperature of air and beer during transportation of a trailer during sunny weather.”

The x-axis of this figure goes for 96 hours (4 days).

The author defined a metric of “shelf-life days” to quantify how long a beer is ‘good’ under varying temperature conditions. For example:

“1 day at 59 °F = 0.47 shelf-life days

1 day at 95 °F = 9.38 shelf-life days”

So, if you use the AB best by duration of 110 days for a beer like Budweiser:

If you continually store the beer at 59 °F the beer will be ‘good’ for 234 days.

In contrast if the beer is continually stored at 95 °F the beer will be ‘good’ for 12 days.

Cheers!

 

Here's what you guys need:

http://shockwatch.com/products/temperature

http://www.drypak.com/temperatureIndicatingLabels.html

 

Interesting. I tried to find access to the paper (free), but could not.
Does it discuss the average or likely temperature the vehicles? Where I live the temperature varies a lot. For example it was 85 yesterday and dropped to about 50 overnight. That probably has its own negative effects.

 

Cool idea, but the results would have more significance if you did a triangle test, with 2 samples of good beer and 1 being the heat treated sample.

 

Yes.

Firstly it is assumed that the average outside temperature is 80 degrees F.

Figure 4 illustrates two curves:

• The air temperature inside the trailer which looks like a roller coaster with the peak being around 90 degrees F and the valley being about 70 degrees F.
• The beer temperature is a rising curve with the start (day 0) being around 68 degrees F and the end (day 4) being around 78 degrees F.

The other assumption worth noting is that the trailer is loaded with 22 pallets of beer. Those 22 pallets constitute a large thermal mass so it takes quite some time (4 days in Figure 4) to reach peak of temperature. Needless to say but a trailer that has a lesser amount of thermal mass would reach a higher temperature more quickly.

Also, it was assumed that all of the beer that was loaded at the start were at 68 degree F. Needless to say but a higher start temperature will result in a higher temperature at the end of the trip (i.e., day 4).

Cheers!

 

Thanks for the info, seems like an interesting paper.

 

How did you cool down the "hot" beer to drinking temperature? By refrigerator or freezer?
I've always imagined this also must have a pretty big impact... I always use a freezer to cool down my room temperature beer; I feel the slower cool down that the refrigerator provides is quite harmful to the beer.

What temperature was the refrigerated beer stored at? Do you keep your beer fridge just above freezing or do you just keep it at drinking temperature? Personally, mine is kept at 33-34 degrees F ; as I feel the colder temp. preserves the beers flavor better.

 

Nice test.

I would likely avoid crowlers and go with the same set of packaged beers.

I'd add two more variables. A beer that gets cold then warms up, then gets cold. I know people freak out when they buy cold beer and they are visibly shaken about it going "bad" on its ride home. Maybe have a 4th that stays a steady 72 (ie store shelf).

1. cold all the time
2. cold some of the time
3. room temp all the time
4. Basically backroom 90 degree non refrigerated truck all the time.

One or the other sensory sampling, I've noticed I do very well. Introduce just a 3rd or a 4th and more than likely, you'll have someone in your group who cant quite make out the "freshest".

In the past, I have done similar sampling with some local IPAs. It would be one IPA. One sample is a fresh growler pour, another is a fresh can, and another is a can that had been sitting in a fridge for about a month. A group of 5 of us had varying answers to what we preferred. Now obviously we did not introduce a bad element like HEAT. But even so, many could not pick out the freshest once we started introducing more variables.

I know you wanted to isolate it to strictly beer trading and a 4 day window. It makes sense, but I definitely feel as others have mentioned, go with a triangle test. Maybe if I have some time, I'll see what I can come up with for my own IPA test