“Ooh, you look much tastier than Crabbe and Goyle, Harry” said Hermione, before catching sight of Ron’s raised eyebrows, blushing slightly and saying “oh you know what I mean – Goyle’s Potion looked like bogies.“
Harry Potter and the Deathly Hallows, J.K. Rowling

Polyjuice potion changes both colour and taste, depending on who you’re transforming into. So how do you convert that idea into a drink for your Harry Potter party? By creating a polyjuice potion kit that’s unique to each person– and you can create this kit using ingredients you find in the grocery store.

How does it work?

The foods we use to create the base colour contain a pigment called anthocyanin. The extracted pigment contains the anthocyanin molecules that will change colour based on the pH it comes in contact with. To create a truly magical experience when mixing your potion, we start with the base colour(purple), add alkaline to alter the colour to a blue or green, then we add acid to transform it into a pink or red.

The ‘magic’ base colour.

If you ever did the red cabbage science experiment at school, you’ll be familiar with this ‘potion’. Plants rich in anthocyanins include blueberry, cranberry, bilberry, black raspberry, red raspberry, blackberry, blackcurrant, cherry, eggplant (aubergine) peel, black rice, ube, Okinawan sweet potato, Concord grape, muscadine grape, red cabbage, and violet petals.
**Please note that I’ve only tested the red cabbage and berries for this recipe.

order	colour	What to add	taste
base	purple	red cabbage or berry water	water with minimal hint of fruit or cabbage
alkaline	blue to green	pH booster drops or bicarbonate soda	slightly alkaline
acid	light pink to red	clear cordial + lemon juice, lime juice or citric acid	flavour

The concocting of polyjuice potion in the Harry Potter series is made up of two parts, so it’s only fitting that we have two stages to make it feel more like a potions

To make this as magical as possible, remember:

Add the ingredients in the order they appear. The first two stages aren’t about tasting, they’re about colours transforming. The final stage is where you add your flavour. Turning the water to alkaline before acid is a must– it would take a lot of alkaline to convert the colour back and runs the risk of tasting terrible!
If you aren’t sure if your guests will stick with the recommended amount, measure out the amount they need into test tubes and small potion bottles.
Only use a clear cordial. The magic is in the fact we are adding to no food dye to the purple, and yet the colour transformation is astonishing to see.

DIY Polyjuice Potion Kit | Harry Potter

Print Recipe

Author: Bryton Taylor

Ingredients

red cabbage OR fresh or frozen berries * see notes

bicarbonate soda OR pH booster drops

water

clear cordial: elderflower, lime, lemon OR flavoured water drops

lemon juice OR lime juice OR citric acid

Instructions

Extract the pigment.

Red cabbage.

•Chop up or grate half a red cabbage (or one small cabbage), place it into a large saucepan and fill with just enough water to cover the cabbage.

•Either let this sit in water for several hours or help speed up the process by bringing to a simmer for 20 minutes until the water is a dark purple.

•Let the cabbage water cool before straining into a potions bottle for serving.

Blueberry, cranberry, blackberry, black currant.

•Place fresh or frozen berries in a bowl, mash to break them up, then pour just a bit boiling water over them.

•Let sit for 5-10 minutes, then strain using a fine cheesecloth or tea strainer.

Create your potion.

•In a glass filled with 250mL of water, add in just enough base colour to change the colour of your water.

•Drop in several drops of pH booster drops or sprinkle a pinch of bicarbonate soda. The colour will turn to a shade of blue to green depending on the pH level.

•Next pour in your clear cordial, following the bottles measurement suggestions for a 250mL drink.

•You may, in advance, add in some additional lemon juice or stir in some citric acid to your cordial before adding, for a more vibrant result.

•Alternatively, you can have another test tube filled with lemon juice or a small potion bottle with a sprinkling of citric acid for the final result.

•Give the potion a final stir with your ‘wand’. The end result will be a shade of pink to red, depending on the acidity level.

Notes

* Berries include blueberries, cranberries, blackberry, blackcurrant.

**Only fresh or frozen berries should be used. The blueberry or cranberry juice that you buy in the supermarkets often contain acidity regulators in the form of lemon juice, so will be too acidic to start with. These berries each have a different starting base colour, however, all can have a magical transformation.

*** You can prepare your base colour the day before your party.

Keywords: harry potter, polyjuice potion

Displaying the polyjuice potion kit

It’s all in the details at a Harry Potter party. Here are some ideas to make your polyjuice potion even more magical.

Make potion ingredients available in vintage glass bottles on the table. The base colour and a variety of cordials with varying amounts of acidity can be displayed in a number of potion bottles.
Alternatively, you might want to measure out correct ingredient amounts for each person and make them available in test tubes in a stand at each table place.
Include at each table setting a ‘mini wand’ aka wooden chopstick for stirring. Search for Japanese chopsticks to find chopsticks that have ornate handles. Place the chopstick in a small box with an Ollivanders label. As an example, these ones on Amazon come with 5 sets– 10 wands in total: https://amzn.to/2V1jIhs

DIY Polyjuice Potion Kit | Harry Potter

How does it work?

The ‘magic’ base colour.