Author: Julie Le
Date: September 23, 2017
What are Preservatives?
Preservatives are ingredients that can be natural or synthetic. They are essential ingredients in formulations to protect the product from microbial growth or contamination induced by consumers during use1. As well as maintaining the safety and efficiacy of the product over the intended lifespan1. It is important to choose the preservative that is toxic to microorganisms but safe to humans.
The classic preservative used in the industry are parabens which, are regulated by the FDA to be safe. However, with popular marketing trends of ‘paraben-free’, the use of parabens have been looked down upon due to their potential health risks. As a result, many consumers are more attracted to the term ‘natural’ when shopping for personal care products creating a growing market in many countries2. For this reason, this article will focus on the natural alternatives for preservation.
Why use Preservatives?
Skin care products are formulated with water to emulsify the ingredients, this gives the smooth texture that we all know and love. As consumers we all love the sound of ‘natural’ when shopping for our products because we all strive for the best for our skin without the use of harmful chemicals. Though, it is important to incorporate preservatives in these formulations because they are havens for microbial growth. Unless, the products are formulated without the use of water, then as a formulator, you may choose to incorporate preservatives or not. However, it is important to keep in mind the conditions the product will be used in as well as the packaging type. Product packaging design provides a physical barrier from the environment where its primary role is to minimize contamination that may be induced by the consumer.
Type of Natural Preservatives
INCI: Humulus lupulus (Hops) Extract
Hop Extract is characterized by its viscous liquid state that appears to be greenish-yellow-reddish brown with a bitter and abrasive odour. Comes from the hop plant Humulus lupulus where the pine cone-like flowering tops undergoes CO2 extraction to obtain the popular ingredient in the beer brewing industry. The key components of hop extracts are humulones (alpha-acids) and the lupulones (beta-acids), where their primary roles are to prevent microbial growth and increase shelf life2. With its wide range of benefits from anti-bacterial to anti-septic, it is no wonder why it has an increasing popularity within the cosmetic industry.
INCI: Azadirachta indica Seed Oil
The incredible Neem (Azadirachta indica) oil is part of the Meliaceae family of which, the seeds are cold pressed. It is characterized by its yellowish brown to dark brown liquid, where at slightly colder temperatures, the oil becomes more viscous and often times – harden. It also has quite a distinguishable odour that is pungent, earthy with a slight nuttiness. With these distinct characteristics, it is important to keep in mind when formulating that this may impart in the odour and colour of the final product. It encompasses a vast variety of beneficial properties when incorporated in skin care products such as anti-bacterial, anti-viral, anti-septic, anti-fungal and insect repellent. There are studies demonstrating the seed oil at a concentration of 0.3% on agar plates was active against Stahylococcus aureus and at 0.4% was active against Salmonella typhosa3. The seed oil at a concentration of 3% on agar plates, was active against E. coli and Proteus species; a concentration of 6.0% was active against Klebsiella pneumoniae3. Ultimately, indicating Neem oil as an excellent choice as a natural preservative and active component.
INCI: Rosmarinus Officinalis (Rosemary) Leaf Extract
Rosemary is characterized as an evergreen perennial scrub with thick, dark green, aromatic, linear leaves. Through the process of CO2 extraction of rosemary leaves, it gives rise to the popular rosemary extract. Rosemary extract imparts a mesmerizing aroma along with other beneficial properties. As it is a natural antioxidant, it is an excellent choice as a preservative through the reduction of oxidation rate ultimately extending the shelf life of products. It is recommended when using 100% pure rosemary extract as a preservative, the effective range is 0.15 – 0.5%4.
Curcuma Xanthorrhiza Extract
INCI: Curcuma Xanthorrhiza Root Extract
Curcuma Xanthorrhiza belongs to the zingiberaceae family, where it is also known as ‘Temulawak’. It is characterized by their banana-type leaves and rhizomes – that is a dark yellow exterior with a bright orange core. Similar to the extracts/oils mentioned, curcuma xanthorrhiza also undergoes CO2 extraction where it contains 80-90% essential oil and approximately 25% xanthorrhizol2. Xanthorrhizol, specifically plays a key role in eradicating bacterium such as Streptococcus mutans. This along with its camphor-like taste makes it an advantageous ingredient in oral care products such as toothpaste, mouth wash and chewing gum. As curcuma xanthorrhiza extract demonstrates anti-microbial efficacy as well as anti-oxidative properties – this makes it another excellent choice as a natural preservatives to extending the shelf life of cosmetic products.
References: 1. Preservative Information. (n.d.). Retrieved June 30, 2017, from http://www.cosmeticsinfo.org/preservative-information 2. Quirin, K. W. (2007). Herbal Extracts in Support of Natural Cosmetics Preservation. Cosmetic Science Technology . Retrieved July 04, 2017. 3. Natural antimicrobials and preservatives: an emerging trend in personal care. (2006, December 18). Retrieved July 05, 2017, from https://www.cosmeticsbusiness.com/technical/article_page/Natural_antimicrobials_and_preservatives_an_emerging_trend_in_personal_care/47233 4. Using Preservatives to Extend the Shelf Life of Your Products. (n.d.). Retrieved July 07, 2017, from https://www.fromnaturewithlove.com/library/preservatives.asp