In the ever increasing trend to treat beer more like wine, there are now dozens of suggestions online for beer / food pairings. There are some serious and useful (don’t get me wrong, I like the food pairing stuff) graphics from places like craftbeer.com to help with this. As far as I can tell, the way to determine if a liquid and a food go together is to collect anecdotes, the lowest form of evidence from a scientific point-of-view.

“Are people doing it currently? Does it make the two things taste better? Then it is a food pairing.” Not a very thoughtful way to determining something.

I’ve been increasingly curious with why things taste good together. I’ve had discussions that do amount to “well I know better” about beer and food pairing, specifically about whether or not beer pairs well with spicy foods. I decided to look into it the way an academic would look into it. I don’t want to take anything away from people like Garret Oliver who wrote one of my favorite books on the subject or Greg Engert, owner of one of my favorite bars. While their opinions are useful and definitely valid, they ultimately boil down to a sort of “argument from authority”…I’m right because I know I’m right sort of thing. Also, advice is separate from measurement and science. I want to know the science behind taste perception, not just looking at peoples advice. There are a dozen blogs on my feed filled with beer / food recipes that are full of good advice. To my pleasant surprise, there is some actual science behind food pairing and some people doing legitimate work to discover not only WHAT foods go together but WHY foods go together.

It turns out that food pairing is studied scientifically and one of the leading hypotheses about how to pair foods is to look at what aroma/flavor chemicals are shared between the two substances. On the surface it makes sense in a “why didn’t I think of that” sort of way. Like goes with like, but more at the chemical level. Pairing two foods that have the same chemical make-up, or the same array of flavor-active compounds, might enhance the flavors, it makes sense at least. What does this observation means for “beer” as a food product.

Obviously, beer is a complicated food product. Beer is a beverage that combines the flavors of primary beer ingredients (malt, water, hops, and yeast) as well as what other spice or adjunct you added to the beer during or after fermentation (coriander, citrus, juices, fruits, honeys, etc). On top of this complexity there are more than 100 different KINDS of beer, and the flavor components of those different styles of beers will obviously affect the flavor and therefore the pairing.

So I was poking around on the internet the other day and came across this article from 2011. I thought it was interesting enough to summarize and elaborate on it here. The authors of the article built an impressive database of flavor/aroma active chemicals and assigned them to different foods, then drew association maps between different food products and showed that foods that shared more chemicals were classically considered to be paired together. Is this definitive? No, absolutely not, but it is a fascinating way to look at food. The basic premise of the article is that chemicals form groups based on what flavor sensations they evoke within your sensory system, chemicals that are similar or the same will generate similar perceptions and so they will pair together. The graphic belwo shows what chemicals are shared in a dish of mussels with a tomato sauce. There are dozens of shared chemical components with taste consequences.

“Cool, you just told me why spaghetti sauce tastes good….neat…” OK OK, this is a BEER blog. Let’s talk about beer.

I’ve touched on some of the chemicals that affect flavors that are produced during a normal fermentation with Saccharomyces species and with Lactobacillus species. But those posts focused primarily on what flavors the yeast or bacteria itself produces, not what flavors the hops or the malts would produce independent of the fermentation. I was curious what flavor compounds were used in this analysis since “beer” was included in the food products. To a beer snob like myself, calling something “beer” raises a lot of questions. It is sort of like calling a food “cheese”…well it’s a place to start but a pilsner and a stout are both beer and both chemically distinct not to even mention mixed fermentation beers that will contain lactic acid as a major product. “Beer”….I left a table at the end of this document with the 229 compounds found in beer (a pale ale) used to make this network of flavor interactions (there were a total of 1106 compounds in the database used) .

That is a busy graphic and hard to read but allow me to summarize it for you. Beer shared at least one compound with 948 different food products (out of 1532 food products in the database). Their analysis of shared compounds between beer and their panel revealed that beer had the most in common with the following Blue Cheese, Cheddar Cheese, Swiss cheese, Gruyere cheese, Beef, Apple, Pork, Liver, Katsuobushi, Milk, Roast, Beef, Coffee, Corn, Cocoa, Galanga, Soy Sauce, Watercress, and Rutabaga. Some of these are not surprising. Really quick, Katsuobushi is dried fermented tuna. I had never heard of it, perhaps I should get out more. Without lumping or editing their database, I pulled out the top 75 hits for “beer” and flavor pairings, table below.

Food Product # of Shared Compounds white wine 118 cabernet sauvignon wine 107 red wine 106 roasted beef 106 jamaican rum 104 rum 103 boiled beef 103 sherry 103 fried beef 103 braised beef 102 blue cheese 102 grilled beef 102 raw beef 102 coffee 101 gruyere cheese 101 parmesan cheese 100 cognac 99 cheddar cheese 97 black tea 97 roasted cocoa 96 roasted green tea 95 green tea 95 swiss cheese 95 cocoa 94 camembert cheese 92 cooked apple 92 sparkling wine 91 provolone cheese 91 botrytized wine 90 mozzarella cheese 90 port wine 90 fermented tea 90 feta cheese 89 rose wine 89 rooibus tea 89 russian cheese 89 domiati cheese 88 dried green tea 88 romano cheese 88 dried black tea 88 limburger cheese 88 brewed tea 88 cottage cheese 88 jasmine tea 88 tea 88 pouching tea 88 ceylon tea 88 seychelles tea 88 kola tea 88 fermented russian black tea 88 comte cheese 88 strawberry 87 sheep cheese 87 cheese 87 soybean 87 cream cheese 87 goat cheese 87 roquefort cheese 87 tilsit cheese 87 munster cheese 87 emmental cheese 87 wine 86 champagne wine 86 peanut butter 82 roasted peanut 82 cured pork 81 roasted chicken 79 milk 78 butter 77 grilled pork 73 tomato 73 uncured smoked pork 72 roasted pork 72 beer 70

There are definitely themes in this list. Such as….wine, beef, tea, and cheese. Also known as the best foods. So not surprising, there are a lot of fermented foods on that list. A lot. What are the flavor chemicals that are driving those interactions exactly? Well, there are several chemicals that appear in dairy, meat, and beer products. The chemicals driving this interaction include o-cresol, 2-butanone, propyl acetate, ethyl lactate, decanoic acid, isoamyl laurate, pyrazine, phenethylamine, thiazole, indole, pyrrolidine, 3-hydroxy-2-pentanone, 2-hepten-4-one, ethyl isovalerate, propyl acetate, n-valeraldehyde, methyl acetate, and guaiacol. Looking at a list of chemicals like that makes you wonder how these lists were made and if they are weighted at all. I traded emails with the authors of the paper and as far as I can tell, the different chemicals were not weighted (or were weighted the same if you prefer) and the lists were populated from the literature and a couple of books that contained lists of compounds found in food products.

If you like beer, eat chicken, beef, pork, and dairy products is the bottom line. Also tea…I’m fine with all of that.

Final Thought

This sort of analysis is a deep rabbit hole. There are a lot of limitations to this sort of thinking and analysis, most notably is you are limited by what compounds you include in the initial analysis and I was initially surprised that ethanol was not on their list (especially since even without it all the alcoholic beverages still clustered together). Ethanol definitely has a flavor and would influence this sort of analysis as well as people’s taste preferences but I understand how that is such a huge contributor that you might not want it in the analysis. It would also affect the solubility of other chemicals that would have flavors…enhancing those. Second, what foods you select are going to bias your analysis. In this respect I think the authors did an amazing job selecting a variety of foods from several cultures that hit several “areas” of food. At times I found the list a little redundant but I should never judge their database building. It would be great to have a database that was 10 or 100x larger though, then you could really do some detailed analysis. Lastly, there wasn’t a serious effort to take into consideration the overall contribution each flavor compound had on the individual food or drink item. The threshold for different taste chemicals would be different and the overall taste detection would be dependent on the concentration of each compound. This would be really hard to do though and I recognize that. Also, it might be misleading as lots of things that do pair do NOT share a compound that is dominant in one of the ingredients. It would be pretty hard to parse that sort of data in a meaningful way.

Like I said above, it would be interesting to do this with a few different kinds of beers. I didn’t include it in the analysis for a couple of reasons but the authors included a second beer they labeled as “bantu beer”…I did not include it in the analysis above because it was so close to the generic beer, they shared the greatest number of compounds of ANY TWO entries in the entire database at 227, grilled beef and roast beef were second at 207 shared compounds. Bantu beer and beer were nearly interchangeable in this analysis, often appearing side-by-side in the cells of the spreadsheet. In fact, the primary difference between the two beers on their list came down to the presence of three simple compounds in the bantu beer not listed in the “beer”: ethylene oxide, methyl myristate, and 1-phenyl-1-propanol. I’m not sure why those compounds were listed with bantu beer and not with the generic beer but perhaps they are present due to the sorghum used in the fermentation. Who knows? Not me. It would be fun to do a stout versus a pale ale or a lager versus an ale though. Perhaps if I have a bottomless pit of time I will do that analysis one day.

Ultimately, one could spend hours pouring over their data and making interesting connections. My primary interest in this centers around the fact that this sort of analysis has the potential to work. Provided you could side step the obvious problems I pointed out in the beginning with chemical

“Across the troubled maelstrom of time, people always need beer.” -Ellen Kushner

Supplemental Information. List of compounds found in beer used for the matching.

jasmone methyl 2-methylthiobutyrate methylsulfinylmethane benzothiazole 2-acetylfuran nonyl acetate 4-hydroxy-3-methoxybenzoic acid 2-methylpyrazine p-ethylphenol isoamyl formate 3-ethylpyridine isoamyl acetate 4-methyl-2,3-pentanedione g-dodecalactone isoamyl octanoate 2,3-dimethylpyrazine ethyl butyrate g-hexalactone ethyl-3-methylthiopropionate pyruvic acid methyl-2-pyrrolyl ketone 3-methylbutanethiol 2-methylbutyl acetate 2-nonanone 4-decenoic acid isoamyl propionate isopentylamine isobutyl formate oleic acid cis-3-hexenal eugenol 1-decanol ethyl isobutyrate 2-ethyl-3,5(6)-dimethylpyrazine undecanal valeric acid amyl butyrate resorcinol 1-octen-3-ol 2-acetyl-5-methylfuran 2-ethyl-5-methylpyrazine 2-hexen-1-ol palmitic acid 2-nonanol g-decalactone hexanoic acid pyridine isoamyl benzoate ethyl 3-hexenoate myristaldehyde 2,4-dihydroxybenzoic acid isoamyl hexanoate 3-hexanone lauric acid ethyl lactate vanillin 3-(methylthio) propionaldehyde s-methyl 4-methylpentanethioate ethyl thioacetate 1-octanol nonanoic acid ethyl octanoate 2-octanol n-furfuryl pyrrole ethyl acetate isobutyl benzoate isobutyl acetate furfuryl alcohol g-nonalactone 4-(2,6,6-trimethyl-cyclohexa-1,3-dienyl)but-2-en-4-one cinnamic acid isobutyric acid decanoic acid hexyl octanoate pyruvaldehyde 2-oxobutyric acid 2-methylbutyric acid d-camphor 6-methyl-5-hepten-2-one g-valerolactone heptyl alcohol isoamyl laurate methyl nicotinate 2-trans, 4-trans-decadienal nona-2-trans,-6-cis-dienal 4-hydroxy-3,5-dimethoxybenzaldehyde vanillin 4-methyl-2,6-dimethoxyphenol pyrrole propyl mercaptan 9,12-octadecadienoic acid (48%) plus 9,12,15-octadeca- trienoinc acid (52%) (methyl esters) nerolidol 2-methylpentanal prenylthiol (+/?) heptan-3-yl butyrate heptyl acetate g-butyrolactone hydrogen sulfide 4-mercapto-4-methyl-2-pentanone ethyl propionate 1-butanethiol citronellyl acetate ethyl nonanoate octanoic acid diethyl sulfide butylamine amyl hexanoate phenethyl butyrate hexyl isobutyrate isovaleric acid 2-ethylpyrazine n-nonanal 4-methyl-2-pentanone dimethyl trisulfide isopropyl acetate (+/?)-2-(5-methyl-5-vinyltetrahydrofuran-2-yl)propi-onaldehyde hexyl butyrate 2,6-dimethylpyridine 2-octanone methyl sulfide propyl alcohol phenethyl acetate hexyl acetate lauryl alcohol 4-hydroxybenzoic acid 2-hexenal 2-methyl-1-propanethiol 4-ethylguaiacol 3-(methylthio)propyl acetate n-octanal 2-ethyl-3-methylpyrazine decanal myrcene 4-hydroxybenzaldehyde trimethylamine 4-hydroxy-2,5-dimethyl-3(2h)-furanone 2-methyltetrahydrothiophen-3-one alpha-terpineol 3-hydroxy-2-oxopropionic acid phenethyl propionate geranyl isobutyrate propionic acid 3-acetylpyridine heptanoic acid 3-methyl-2-oxobutanoic acid 3-(methylthio)propanol lauric aldehyde phenylacetaldehyde phenylacetic acid methyl mercaptan ethyl heptanoate 3-phenylpropionic acid 2,3,5,6-tetramethylpyrazine 2-methylbutyraldehyde benzyl isobutyrate fenchyl alcohol 2-hydroxybenzoic acid 3-methylbutyraldehyde octyl butyrate 2-trans, 6-trans-nonadienal 4-ethyl-2,6-dimethoxyphenol geranyl acetate 1-penten-3-ol a-phellandrene ethyl formate isobutyl alcohol isobutyl hexanoate myristic acid 5- and 6-decenoic acid salicylaldehyde 2-methyl-3-butenal 2-methoxy-4-vinylphenol pyrazine isoamyl nonanoate phenethylamine heptyl formate maltol 5h-5-methyl-6,7-dihydrocyclopenta(b)pyrazine l-malic acid 2-methoxy-4-methylphenol 3-phenylpropionaldehyde 2,3,5-trimethylpyrazine 2,3-pentanedione thiazole 3-methylbutyl-2-methylpropanoate 2-heptanone 2-acetylpyridine indole n-butyric acid pyrrolidine 2-pentanone p-vinylphenol 3-hydroxy-2-pentanone furfuryl acetate glycerol 3-methyl-2-buten-1-ol phenethyl hexanoate 2-acetylthiazole 4-propenyl-2,6-dimethoxyphenol methyl hexanoate 2-pentanol 2-hepten-4-one methyl disulfide phenethyl isovalerate ethyl isovalerate 5-methylfurfural diacetyl citronellol propyl acetate 4,5-dimethyl-3-hydroxy-2,5-dihydrofuran-2-one propionaldehyde carvacrol n-valeraldehyde nerol 2-methyl-2-pentenal methyl acetate 3-hexenoic acid phenethyl alcohol isopropyl alcohol phenethyl octanoate phenol s-methyl thioacetate phenethyl isobutyrate nonyl alcohol s-methyl hexanethioate 2-heptanol guaiacol