accidental discovery: walnuts can make things purple?

So I’ve made this recipe belonging to a buddy of mine about five times without any anomalies and consistent flavour. It’s a simple method using an immersion blender, comes up a creamy golden brown, with a little separation continuing after a cloth-straining (no big deal as it’s blitzed into a creamy drink). It’s walnuts, honey, vanilla, water.

Out of nowhere this week, and originally to my absolute horror, as I began blending the walnuts into the honey it began to turn purple… and then black. What the hell had I done? What new element had I introduced? It was practically inky and the foam on top was cement grey-purple.

Turns out this is one the coolest accidents to come my way. It was an acid that is commonly found in the skins of walnuts, called gallic acid. After a bit of google searching I ended up on baking and beekeeping forums, and the wikipedia page of an ink used between the 15th-19th centuries, and this is what I’ve got:

  • A problem for bakers is having their walnut breads turn purple because of gallic acids found in the skin.
  • A highly sought after and quite rare type of honey that occurs naturally is dark purple. Many apiarists believe this is because of high acidity in the soil in the vicinity of hives.
  • Iron gall ink was prepared using iron salts and tannic acids from oak gall nuts (where the name for gallic acid is derived.) A well prepared iron gall ink would gradually darken on the paper to a dark purple colour.

I totally triggered a chemical reaction accidentally. Perhaps the honey contained something that interacted with the walnuts? Maybe I didn’t bring the water entirely to the boil?

Now where do I find this actually purple honey, though?

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artificial flavours: sometimes manhattan smells like maple syrup

Reproducing a flavour out of entirely different ingredients is such a cool trick. Isolating the things that make us taste something, and then being able to copy them so well that we can convince our own tongues? Magic.

I got so into this idea when I came across the modern myth about artificial banana flavour. So this story goes, the reason banana syrups, lollies, and flavoured milks don’t taste that close to real banana is because when the flavouring was first being synthesized, (mid-1800s), it was based on the Gros Michel, which was then pretty much wiped out by a fungal disease in the 1950s. What we see the most of now, the Cavendish, survived, but it’s flavour profile is apparently much milder. Actually, it seems that maybe real bananas weren’t readily available at the time banana essence is first seen referenced, so maybe people were eating artificial banana flavours and when real bananas came along they favoured the Gros Michel because its profile was similar to what they were already used to. Seriously, I love this story more, because it means that chemists tricked people into deciding what a thing should taste like before they’d ever even seen it. (Nadia Berenstein wrote a thing about it if you want to read more about bananas. I highly recommend her blog as a resource in general. She writes a lot on the topic of synthetic and artificial flavours.)

Vanilla essence is a cool one. Vanillin is used, which is a compound that has the exact same structure as the main component of real vanilla, which is why they are really hard to distinguish. The chemical that occurs in barrel aged whisk(e)y to produce the taste of vanilla? It’s the same as the one that makes real vanilla bean taste lIke, well, vanilla. I’m simplifying a little here, but you get the idea.
I read once somewhere that strawberry is really hard to reproduce because its flavour profile is really complex, and can’t be defined by just one or two chemicals.

I’m working with the head chef at the moment to create a drink and food pairing. I told him that I would like to use fenugreek, so he has suggested that an element of the dish will use Château-Chalon. Château-Chalon is an appellation controlled wine from Jura that can only be made from Savagnin in the vin jaune style. It’s known for its nutty flavours, and as it ages can develop curry flavours because of the presence of sotolon. Sotolon is also know as fenugreek lactone. The molecule sotolon was first isolated in 1975 from fenugreek. It is the major aroma and flavour component of fenugreek seed and can also be found in lovage. It’s also present in molasses, aged rum, aged sake and white wine, flor sherry, roast tobacco, and even a type of mushroom. It is also thought to be responsible for the mysterious maple syrup smell that has wafted over Manhattan every so often since 2005. Yup, imitation maple syrup is made with sotolon. We’re going to use the same chemical, present in different ingredients naturally, to create a complimentary theme.