The German chemicals firm will make the compound – the world’s best-selling aroma ingredient – at a new plant it is building in Ludwigshafen, using the plant oil extract citral as its starting material.
BASF’s production method, described here, uses chiral catalytic hydrogenation and continuous distillation to minimise the post-processing and centrifugation steps that are required by traditional mint oil freeze-based manufacturing approaches.
L-Menthol’s primary pharmaceutical industry applications are as a taste-masking excipient or as an intermediate in active pharmaceutical ingredient (API) synthesis. It is also used in a wide variety of over-the-counter (OTC) drugs, mouthwashes and toothpastes.
Spokesman Andres-Christian Orthofer told in-Pharmatechnologist.com the decision to begin producing L-Menthol is based on customer demand for an alternative to existing menthol sources.
“Currently, we see a lack of capacity of synthetic menthol in the market. As a future producer of synthetic menthol, we do not expect a significant overcapacity in the marketplace but rather a shift in the source of supply pattern.
“In particular as compared to natural sources of menthol we offer stable production, constant, very high purity and reliable supply.“
He added that pharmaceutical grades will be available as 20 kg easy-to-disperse flakes, 180 kg drums and - on request - 20 mt tanks, and explained that: “BASF aims to be the top supplier of L-menthol to the pharmaceutical industry.”
Global demand
Current global ‘natural’ menthol production capacity is about 20,000 metric tons a year – around a quarter of which is used by the pharmaceutical industry1.
In recent years, however, the quantity of mint produced, and hence its price, has fluctuated for a variety of reasons. This has seen industry interest in synthetic menthol increase.
At present the synthetic menthol market is dominated by Symrise and Takasago, which produce approximately 5,000 tons of the compound each year using the raw materials thymol and myrcene, respectively.
Lanxess, a key Symrise supplier, announced its intention to expand production capacity at its intermediates plant in Krefeld, Germany in July.
1 Clark, G.S., Aroma Chemical Profile: Menthol, Perfumer & Flavorist, Vol. 32 (12), 38-47 (2007).