Beetroot Pigment and Color Stability


The lip stain (and 'kissy' lip-print) you see up there is from last year. I was so pleased with the formula, it was included in my book The Art of Making Glycerites for Cosmetics. The lip stain is even featured on the cover.

The colorant is sourced from beetroot and packs a pretty pink punch of color – for a while.

Plants as cosmetics colorants are full of interesting surprises and can be a bit of a challenge to work with.

Ahem, that was a serious understatement.

Since I started testing various 'plants as pigments' in my self-appointed quest to develop a series of 100% plant-based makeup products (that double as skincare), I have to admit plants as cosmetics colorants are a massive and multi-faceted challenge to work with.

One of the biggest and most challenging issues is color stability.

Today, we're going to get a little up close and personal with the coloring abilities of beetroot (INCI: Beta Vulgaris).

Beta Vulgaris 

Although we are mainly approaching beetroot from a make-up coloring perspective, there are a few additional beneficial properties I got a little excited about while researching, so there are a few included extra tidbits of info.

And since we're talking about make-up, let's take a quick look at the chemical make-up of this color-packed vegetable.

(see how I cleverly snuck a little science introduction in there while still using the word make-up?)

Betanin: What Makes it So Red

The main reason for beetroot's deep rich color is a substance called betanin. Beetroot has a lot of it. A research paper published in 2011 states about 75 - 95% of the total coloring matter in beetroot is betanin (ref.)

One might assume – as it is plant-based and all – the color is safe for consumption and other uses.

One assumes correctly.

Beetroot is approved for use as a colorant in food and cosmetics where the pigment mixture is used in the form of powder or as juice concentrate (ref.)

As you can see from the pic directly above, beetroot crystals (which is freeze-dried juice) will produce a rich, intensely colored glycerite.

Science Says Beetroot has Even More to Offer

Apart from providing us with a fabulous color, there is growing evidence that suggests beetroot's natural colorants may help reduce risk of cardiovascular disease and other diseases associated with aging (ref).

It also looks like betanin has potential blood pressure lowering effects (ref).

So despite the challenges of working with it as a colorant, it's hard to dismiss the added benefits.

Plants vs Minerals

It may seem odd to compare plants to minerals, but from a colorant angle, mineral based pigments are an indisputable benchmark.

I mean let's face it, micas and oxides are rock-steady color-stable (pun intended).

When you think about it, it kind of makes sense. How long does it takes for a rock to form as compared to a plant?

Even though a plant-based color may offer benefits a mineral colorant can't, the stability issue can't be ignored.

Nobody wants their carefully chosen eyeshadow or lipstick to morph a different shade over time.

So that's a challenge.



How Beetroot Performs as a Colorant

I've worked with beetroot powder and crystals in different formats and mediums. There are both ups and downs.

The crystals will produce a surprisingly stable-colored glycerite (check the photo a bit higher up). A self-preserving beetroot glycerite I made in December of 2017 continues to be stable in every way as I write this (just over a year later).

The color stability problem happens when other ingredients come into play.

To some degree, keeping the pH at a certain level can help extend the stability of the color stability (ref), but it still won't come anywhere close to the stability of mineral pigments.

The photograph just above shows a lip-print made on the January 20, 2018 shortly after the lip stain was made, and again about 3 months later (May 10th to be exact). Even though the product is still good, there is no denying the color change.

I will continue working with beetroot as a colorant  - partly because it's got so much potential and partly because it has added benefits, but mostly because I can get pretty stubborn about solving my own self-appointed challenges.

Stay tuned for more plant colorant fun!

Do Tell

If you work with plant colorants, I'd love to hear a bit about your experiences! Please share in a comment below.


More About Beetroot, Betanin, and Color

Red Pigment of the Root of the Beet - the Preparation of Betanin, jbc.ord
Betanin, the Main Pigment of Red Beet, molecular origin of its exceptionally high free radical scavenging activity, HAL archives, ouverts.f
Betanin - a Food Coloring with Biological Activity, pubmed
Degradation of Color in Beetroot, Journal of Food Science Technology
Betalain, Wikipedia



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