THICKENERS IN COSMETICS
Thickeners in cosmetics have several important roles that can affect the stability and quality of the final product. There is no one-size-fits-all thickener, but the choice depends on the nature of the product and the properties you want the thickeners to impart. Let's take a closer look at the most well-known and widely used thickeners in cosmetics.
THICKENERS IN COSMETICS
The main role that thickeners have in cosmetics is to increase viscosity, i.e. to thicken the product. This is particularly useful when you are creating light creams, gels or emulsions. Thickeners give them the viscosity they need without having to use solid vegetable butters, which would unnecessarily grease the product. Thickeners also allow you to prepare pleasantly light serums with only a water base. It is the thickeners that ensure that these products are not too runny and apply well.
Another function that thickeners have in cosmetics is to stabilize emulsions. They are found together with emulsifiers in formulations and promote the stability of the resulting products. As mentioned above, thickeners allow to reduce the amount of solid fats (vegetable butters) in products that would otherwise be needed to thicken the product. Therefore, thickeners are particularly useful in cosmetics for oily or acne-prone skin.
In addition, thickeners allow you to vary the texture of the resulting products. In fact, some thickeners are known to produce very fine emulsions with no lumps and a pleasant texture to the touch. Thickeners also allow you to influence the spreadability of the product or the dispersion of the exfoliating particles in the product.
THICKENERS AND THEIR PROPERTIES
All of the aforementioned properties of thickeners are due to the fact that, upon contact with water or other water-based ingredientsbased ingredients, they begin to increase their volume and build interlocking polymer structures at the molecular level. Natural thickeners are mainly different types of polysaccharides which have different interconnected building units that allow them to increase their volume.
This phenomenon is characteristic of natural thickeners, which include in particular vegetable gums. In addition, there are synthetic thickeners, but these are mostly used in the wholesale cosmetics industry and may work on a different principle from natural thickeners.
THICKENERS IN FOOD
It is now common practice to use thickeners in foods, not just cosmetics. Just plain gelatine is already classed as a food thickener and is commonly used in the confectionery or meat industry. Thickeners based on pectins or agars are used extensively in the production of jams. Cellulose is one of the constituents of dietary fibre and is also used to thicken various types of food. According to their origin, thickeners can be divided into several categories:
THICKENERS OBTAINED BY FERMENTATION
In this case, thickeners have been produced using microorganisms characterized by the production (or overproduction) of a particular type of thickener. Among the thickeners obtained by fermentation are xanthan gum, sclerotium or gellans.
THICKENERS OBTAINED BY EXTRACTION
By extraction, thickeners are obtained from natural plant materials or algae. For this reason, these thickeners include in particular seaweed agars, then pectins or cellulose from plant sources. They also include carrageenans and alginates.
THICKENERS OBTAINED DIRECTLY FROM PLANT PARTS
These are thickeners that are obtained either from seeds such as guar or locust gum, or from tubers such as konjac powder.
THICKENERS IN MIXTURES
When creating your own cosmetic recipes, you don't have to use thickeners alone. You can create your own blends of thickeners in individual products with the viscosity and texture you want. Some thickeners, such as xanthan gum, give products a high viscosity, but such emulsions usually do not have the finest texture. Therefore, if you want to create creams that are smooth and luxurious to look and feel, it is a good idea to use thickeners that provide such a benefit, such as konjac powder.
On the other hand, thickeners that have a nice texture may not give the desired viscosity, so you can try combining two or three types of thickeners to achieve the desired effect in cosmetics.
When deciding which thickeners to use in your product, you have a wide range of choices. Be inspired by a few of the most commonly used thickeners, which you can read about below.
Konjac is one of the vegetable thickeners obtained from the tubers of Amorphophallus Konjac found in Asia. In addition to cosmetics, it is also used in the food industry. It contains glucomannanes, which are capable of increasing up to 10 times their volume in water. The advantage is that it forms transparent gels without a sticky feeling. Konjac is particularly stable in acidic pH, so it is one of the thickeners you will use in products containing AHA acids. In addition, konjac powder is rich in vitamins A, C, D and B group, it also contains lipids, fatty acids and proteins.
Xanthan gum in cosmetics makes it simple and easy to form a gel or thicken a product. It is thus one of the most widely used and versatile thickeners. It is obtained using biotechnology with the help of the bacterium Xanthomonas Campestris. Its affordable price makes it suitable for experimentation by beginners, but it certainly belongs in the basic kit of those who are more experienced in the production of home cosmetics.
It can be used alone or together with another thickener in recipes. In products, it always appears together with glycerin, which allows it to dissolve, and only then other ingredients are added to this mixture. Dissolving xanthan gum in glycerin will allow you to avoid the formation of lumps caused by the xanthan gum not hydrating evenly. At the same time, xanthan gum is one of the very stable thickeners effective in small doses (1% is usually sufficient in shampoos or shower gels). Its thickening effect can be increased by adding 0,5 % sodium chloride.
Hyaluronic acid is not classified as a typical thickening agent because it is primarily used in cosmetics for its moisturizing effects, which is why it is often applied to the face as a cream or serum. Nevertheless, it is able to bind water to itself very effectively, and so helps to thicken water-based (i.e. oil-free) serums without the use of an additional thickener.
The thickening effects of hyaluronic acid depend primarily on its molecular weight. This is usually given in units of Daltons for hyaluronic acid. The more Daltons an acid has, the better it will thicken. For hyaluronic acid types that thicken well, you may also see the term high molecular weight.
The downside of hyaluronic acid is its higher price, on the other hand, if you use hyaluronic acid in your serum, you usually don't need to add other thickeners anymore.
Similar to konjac powder, guar gum or guarana gum is one of the thickeners derived from plants, specifically the beans of the Cyamopsis Tetragonoloba plant. The use of guar gum is versatile, in addition to being classified as a thickener, it helps to stabilize and partially form emulsions. Guar gum is also used in the food industry due to the fact that it thickens very well to a paste-like consistency. This is also why you will often find it in toothpastes. The disadvantage is that it produces less transparent solutions and can cause a sticky feeling on the skin.
There are a few rules for using guar gum in cosmetics, which distinguishes it from other thickeners. Guar gum is characterised by a high pH (above 9), but it is only effective in thickening solutions at pH 7, so products containing guar gum must be acidified, for example with a citric acid solution.
This exotic vegetable gum is derived from the hardened resin of the African Acacia tree, hence its INCI name Acacia Senegal Gum. It is composed of polysaccharides and glycoproteins and is classified as a thickener, which not only increases the viscosity of products, but is also an active ingredient. Specifically, gum arabic serves as a humectant and partly as an emulsifier and stabilizer.
Carrageenans are thickeners very popular in vegan cosmetics as well as foods. They are in fact a non-animal alternative to gelatin. Carrageenan is extracted from the red seaweed Chondrus crispus, in addition to its thickening effects, it has a role in cosmetics as a gelling agent, emulsifier and stabilizer. It helps moisturize the skin, but especially the hair, which is why it is popular in shampoos and conditioners. It is also widely used in these products because it is well compatible with other surfactants and is capable of forming a foaming gel. It is also stable over a wide pH range.
In addition, carrageenan is popular for its mineral content such as magnesium, calcium, zinc and manganese. It is soluble in hot water.
This article was prepared for you by Ivana Jačalová.