This Easter weekend, most of us will find ourselves reaching towards a certain kind of shiny, foil-wrapped sweet treat. Fondant-filled, nut-coated, confectionery-containing: Easter eggs come in all shapes and sizes, but they all have one crucial component in common. Chocolate.
While the biochemistry of chocolate may not be at the forefront of your mind while you accidentally work your way through a family-sized mound of Easter eggs (or is that just me?), there is some rather fascinating science behind it.
Let’s start with the fundamentals; chocolate is made from products which originate from the cocoa bean, derived from the plant Theobroma cacao which is traditionally found deep in the equatorial rainforests of the Americas. It contains cocoa mass and cocoa butter as well as added sugar. Dark chocolate contains just these principal elements whereas milk chocolate contains extra milk solids and fats, and white chocolate is akin to milk chocolate without the cocoa base. It is the presence of the cocoa butter which gives chocolate its characteristic melt-in-the-mouth texture due to its low melting point.
Historically, cacao was viewed as magical and mystical; it played an important role in early American cultures where it had many uses ranging from medication to currency (first occurrence of chocolate coins?!). Although today chocolate is often viewed as a food with minimal nutritional value; from the middle of 17th century to the 20th century Europeans praised the dietary and healing properties of cacao. Additional uses for chocolate included stimulating the kidney and treatments for anaemia, tuberculosis, fever, and gout. The concept that chocolate had health beneﬁts pervaded throughout much of Europe until the 20th century, after which it tended to be viewed as a non-nutritional confectionery food that provides only calories and fats. However, certain chocolates can provide signiﬁcant amounts of a number of essential nutrients, and it can be a rich source of ﬂavonoids.
Chocolate is the most commonly craved food and, for most chocolate cravers, non-chocolate substitutes are inadequate. Fancy a stick of celery to curb that desire? Thought not. Chocolate is not a natural product, and thus its appeal depends on its individual constituents and their unique combination. Chocolate is sweet, raising the possibility of confusion between chocolate craving and sweet craving, but it also contains fat.
Since chocolate -craving has some features of addiction, attempts have been made to identify any psychoactive ingredients. Several candidates have been identified (the biogenic stimulant amines caffeine, theobromine, tyramine and phenylethylamine have all been implicated), but their concentrations are too low to have a significant psychoactive effect and they are also present in higher concentrations in many non-craved foods. Chocolate contains two analogues of anandamine similar to the cannabinoid responsible for euphoria from cannabis. However, any association with pleasure from chocolate is likely to be indirect as the analogues inhibit breakdown of endogenously produced anandamine. Chocolate may interact with a number of neurotransmitter systems (including dopamine, serotonin and endorphins) that contribute to appetite, reward and mood regulation.
Although addictive behaviour is generally associated with drug and alcohol abuse, chocolate may evoke similar psychopharmacologic and behavioural reactions in susceptible persons. However a review of the literature on chocolate cravings indicates that the hedonic appeal of chocolate (fat, sugar, texture and aroma) is likely to be a predominant factor in such cravings. Other characteristics of chocolate, however, may be equally as important contributors to the phenomena of chocolate cravings. Most likely, a combination of chocolate’s sensory characteristics, nutrient composition and psychoactive ingredients will ultimately form the model of chocolate cravings.
So this Easter whilst helping yourself to your tenth egg-shaped chocolate product (again, is this just me?), spare a thought for the biochemical processes triggered in your body. Then perhaps call Chocolate Addicts Anonymous. You might find me in attendance at their next meeting…