A new study, published in the Journal of Agricultural and Food Chemistry, describes how scientists can identify whether or not coffee purporting to be Kopi Luwak, or Asian palm civet coffee, is authentic.  Kopi Luwak is an exotic coffee from Indonesia.  It is made from coffee berries that have been eaten by the Asian palm civet.  Despite being known as the world’s most expensive coffee, consumers have no means of knowing whether or not the coffee is actually from the Asian palm civet.

Researchers used the extracts of 21 coffee beans from three areas of coffee cultivation.  They explored significant metabolites present in the coffee beans to identify distinct markers of the coffee varieties.  These discriminant markers used certain ingredients, including citric acid, malic acid, and the inositol/pyroglutamic acid ratio, to distinguish between original Kopi Luwak, fake Kopi Luwak, a 50 percent Kopi Luwak blend, and regular coffee.  This study is the first to address validation methods for Kopi Luwak, demonstrating a successful method for doing so.

Raven’s Brew Coffee describes Kopi Luwak as the world’s rarest coffee drink.  The Asian palm civet, also known as the Luwak, lives in the coffee plantations of Java, Sulawesi, and Sumatra.  Luwaks eat the ripest coffee cherries, but are unable to digest the coffee beans.  They excrete the beans and deposit them on the jungle floor.  Stomach acids and enzymes create a unique fermentation process for the beans that go through the Asian palm civet’s digestive system.  The beans are collected by locals and then used to make the expensive coffee.

According to USA Today, products labeled as “civet coffee” or Kopi Luwak go for $150 to $227 per pound.  It is still unclear what makes Kopi Luwak taste different, with some coffee makers claiming the digestive process changes the beans and others stating that it may just be the Luwak selecting the tastiest cherries it wants to consume.

Without a test for the veracity of their claims, unethical coffee producers are able to scam adventurous coffee drinkers seeking a taste of luxury.  This study demonstrates the existence of a possible “metabolic fingerprint” that makes Kopi Luwak identifiably unique.  In particular, civet coffee has higher levels of citric and malic acids.  The inositold/pyroglutamic acid ratio is also a specific amount.  This study uses the science of metabolomics, which is research focused on metabolites.  Scientists use gas chromatography and mass spectrometry to detect the presence of specific metabolites.  While the process still needs to be refined to be used on wider scale for authenticating Kopi Luwak, it is a good start for protecting consumer interests.