Analysis of fragranced products
Odour profiling and ensuring product safety
Analysis of fragranced products is of great importance for manufacturers, whose reputation may rely upon the olfactory qualities of their products consistently meeting customer expectations.
A vast range of fragranced consumer products may be monitored for their odours, including:
- Ointments and topical creams.
- Tobacco products.
- Distilled extracts and essential oils.
- Toiletries, including deodorants.
- Cleaning products.
- Air fresheners.
- Scented candles.
- Surface polishes and coatings.
As is the case for food, fragrance-profiling such products is a challenge because of the presence of many VOCs at a wide range of concentrations, resulting in a highly complex sample matrix. In addition, characteristic (or undesirable) ‘notes’ can frequently result from just one or two trace-level compounds with a disproportionately high odour-activity.
Fortunately, however, improvements in analytical techniques have made it much easier to investigate VOCs in fragranced products. Current interest is in three main areas:
- Fragrance profiling – Understanding the factors that give rise to the fragrance differences between similar products – information that in turn provides the basis for product improvement.
- Harmful chemicals – Determining levels of suspected allergens or potentially harmful chemicals in the products. This also has relevance in an environmental context, where the presence of semi-volatiles in waste water is of current concern.
- Off-odours – Understanding the origin of VOCs giving rise to off-odours or taints, and so ensuring production-line consistency of products from batch to batch.
In certain situations – as for studies of air fresheners – analysing both the products themselves and the environment in which they are used can help the manufacturer to understand which volatile components are likely to be experienced by the customer when the product is in use.
Whatever the focus of study, every aspect of the sampling and analysis protocol needs to be optimised in order to detect and identify the the widest range of analytes. Markes offers a range of solutions for the sampling and analysis of volatiles from fragranced products.
|Detecting compounds in complex matrices || |
Aroma profiling of fragranced products often requires detailed interrogation of complex chromatograms, to confirm the presence (or absence) of key target components, such as trace-level odour-active or taint compounds. It is also often necessary to determine the non-target compounds present, for instance when omparing similar products.
Markes’ TargetView software can help reduce the amount of time spent on these tasks. Through a combination of ‘intelligent’ background compensation, compound deconvolution and library matching, it does away with the need to manually process complex GC–MS profiles, producing a simple report that lists the analytes found in the sample.
What Markes can offer
Thermal desorption systems
Sampling vapours onto sorbent tubes, with analysis by thermal desorption (TD), is a useful method for analysing fragranced products, because it provides the high level of concentration enhancement needed for detailed chemical analysis. It also involves minimal sample preparation and is readily automated, and is so a convenient alternative to conventional sample preparation methods.
In addition, Markes’ UNITY-xr and TD100-xr thermal desorbers are particularly well-suited to the challenges of analysis of fragranced products, for the following reasons:
- The short, inert flow path ensures compatibility with reactive compounds such as mercaptans, amines, and oxygenated species, which often have very low odour thresholds.
- The cryogen-free focusing trap allows selective elimination of unwanted, high-concentration interferents including water, ethanol and acetic acid, which might otherwise compromise detection of trace-level target compounds.
- The backflush operation of the focusing trap allows use of multi-bed sorbent tubes, enabling simultaneous analysis of very volatile and semi-volatile compounds from a single sample.
In addition to the above-mentioned analytical systems, Markes offers a range of TD-compatible options for sampling:
- Headspace analysis for extracting representative odour profiles from a product.
- On-line sampling and near-real-time sampling for monitoring of changes in odour profile with time.
- Alternatively, when the analytes are sufficiently concentrated, grab-sampling of small volumes of sample using Markes’ Easy-VOC, or pumped sampling using Markes’ ACTI-VOC, is both quick and convenient.