Where is Your Chocolate From? — Chromatography Traces Its Origins

Knowing exactly what you are eating and drinking seems to be of increasing importance as people switch from mass-produced produce to ‘designer’ brands. Organic fruit, vegetable and meat sales have all increased in recent years. Single-origin coffees are on the lips of all coffee drinkers searching for the best brew possible. Even craft beers from microbreweries are to be found on the cobbles of Coronation Street.

The latest foodstuff to join in is chocolate. A walk down the confectionary aisle in your upmarket supermarket will reveal chocolates made from beans from one specific country — even in some cases from a specific estate or plantation. These products are sold for a premium, hence, the importance for knowing that what’s on the wrapper is what’s on the inside.

Single origin — Always better?

The flavour profile of chocolate — just like coffee or wine — can be complex. This is due to the many different chemicals that can react with the taste and odour receptors in your mouth and nose. There are so many things that go into making the chocolate taste the way it does. The starting point is the beans — and the beans flavour profile — and that is before the expert chocolatier gets their hands on the beans.

There are many variables that affect the flavour profile of the beans — but perhaps the main variable is geographic location as this ultimately affects the other variables. It is geographical location that affects soil, climate and exposure, all variables that affect the taste of cocoa beans and coffee beans — another product sold with a single origin premium.

But post-production also has an impact on the taste and quality of the finished product. And as with coffee beans, the type of drying, washing and roasting has an impact on the flavour of the chocolate beans —and that is before the chocolatier uses his expertise in creating a chocolate masterpiece.

Where is your chocolate from?

A recent paper in Food Analytical Methods has used chromatography to analyse the chemical composition of cocoa beans to help determine their geographical origin. The researchers used high performance liquid chromatography with a diode array detector and mass spectrometry (HPLC-DAD-MS) to analyse chocolate to investigate the country of origin. Using chromatography to analyse chocolate is discussed in the article, Rapid Screening of Volatile and Semi-Volatile Organic Components in Cocoa Beans and Chocolate Products Using a Portable GC/MS System.

They tested 47 chocolate samples with three different types of cocoa beans from 12 different countries. The main components analysed were polyphenols including catechin and epicatechin. After the chemical analysis, using a statistical process known as Principal Component Analysis (PCA), they could generate polyphenol profiles that could be used to identify chocolate samples into different locations and bean type.

Could you tell your African from your South American chocolate?