HOPS are the main ingredient in the production of beer. Hops are what gives the beer its distinctly bitter taste but unknown to most people, HOPS also acts as a natural preservative. The use of hops in traditional beer was more as a preservative than a flavoring agent ( who would want a bitter tasting beverage? ) but the taste caught on and HOPS became synonymous with beer.
But do HOPS really work efficiently as a preservative? Lets look at the science behind this phenomenon.
Two chemists, Zanoli and Zavatti in 2008 showed that HOPS demonstrated a characteristic mechanism of microbial control in beer which is loaded with microbe forming nutrients. HOPS inhibited gram positive bacteria such as as Lactobacillus, Streptococcus, Staphylococcus, Micrococus, Bacillus, and Pediococcus. The exact mechanism by which HOPS inhibit bacterial growth was explained by Simpson in 1993. ). β‐Acids, α‐acids, and also iso‐α‐acids are incorporated into cell membranes where they act as mobile‐carrier ionophores, catalyzing processes including the electroneutral influx of undissociated molecules, exchange of protons for divalent cations such as Mn2+, and efflux of the resulting complex. This leads to the intracellular accumulation of protons, dissipation of the transmembrane proton gradient, decrease in proton motive force (pmf)‐driven uptake of nutrients, starvation, and cell death. In simple terms the acids in HOPS destroys the cellular integrity of bacteria causing them to starve and die. Simple enough!!
Not just beer but the use of HOPS as a food preservative was demonstrated by scientists (Kramer B, Thielmann J, Hickisch A, Muranyi P, Wunderlich J, Hauser C.). The efficiency of hop extracts as a natural food preservative was tested in a model meat marinade at 2 and 8°C, respectively, and on marinated pork. The experiments showed that Gram-positive bacteria were strongly inhibited by hop extracts containing β-acids and xanthohumol.
The demand for cosmetics with an all natural label is growing and the ability to use naturally occurring anti microbial compounds poses a challenge to most companies. However, these natural compounds do exist and companies that have the will, shall find the way. It’s all about commitment to your customers and a motive beyond profit.
The author is a Natural product scientist that produces all natural cosmetics.