Chemicals in My Food

Hershey Foods owns Hershey Park, a chocolate-themed theme park, in, unsurprisingly Hershey (“the sweetest place on earth”).  Associated with the park is the rather wonderful Hershey Chocolate World; a museum and “edutainment” on chocolate manufacturing.   Their latest attraction allows you to “build a bar”.  You buy a ticket ($15!), put on an apron and hairnet, and then use a touch screen terminal to design your product.  You can choose the type of chocolate (only milk on the day I visited), up to three inclusions, and whether to add sprinkles on the top.  You then go to the production line, pull a lever and release a little “canoe” of solid chocolate that joins a line moving down a conveyer belt.  Your bar is tracked as it passes under a series of depositors which either delivers the inclusion into the canoe or not depending on what you asked for.  Your bar moves under an enrober which covers the inclusions and fills the canoe with liquid tempered chocolate and then onto a vibrator to try to shake out the air bubbles and flatten the surface.  From there the product goes into a cooling tunnel for about ten minutes while you design your own packaging sleeve in time to see it packaged when boxed then your sleeve is added manually and you get your $15 chocolate bar.

Technically the exhibit is very impressive.  The chocolate canoe with dry inclusion fillers was a clever way of visually demonstrating the assembly of the product but is not a realistic demonstration of the real process.  The clever part is the process control to keep people and product moving through the exhibit reasonably quickly and in sync with one another.  Rockwell Automation is listed as a sponsor of the exhibit and I would love to know the amount of time they had to put in to make it work.  

Scientists often struggle to defend themselves against the accusation that their subject is boring.  “Difficult yes, boring no” we argue.  “Admire our creativity! Marvel at our insights! Some of us even own Macs!”  All of these things are true but they disguise the need at the core of practical science for lots and lots of incredibly careful, repetitive and boring work. 

Measure something.  For example, say the average particle size of some emulsion droplets in a cream sauce before and after cooking.  Hooray! Cooking increases the droplet size of this particular emulsion.  Before you start writing that up though, you should consider what else could have contributed to your result.  Perhaps you made an error in weighing out your ingredients (100.4 g and 99.6 g of oil would weigh the same if your balance only reads to the nearest gram), perhaps the heating was uneven, perhaps the protein didn’t have enough time to dissolve, perhaps, perhaps, perhaps, perhaps.  At the end of your first experiment, you have two numbers that differ but you have no idea if that difference is due to the main effect you are excited about. 

So you replicate the experiments.  Do it exactly the same – weigh out the ingredients, mix them up, measure the droplet size, cook and measure again.  Then do it again, and again, and again until all the little “noise errors” average out and you are left with the only persistent difference being the major effect you hope is there. [Insert statistics here]. 

Many new scientists struggle to understand that the point of the replication steps is to do exactly the same protocol again and again.  You are not looking to improve your process at this stage just repeat it, warts and all.  If a new and more precise balance is delivered in the middle of the experiment, just ignore it and continue with what you started with.  Do exactly the same experiment again and again.  This is the boring part of science.  You know what you expect the result to be but you have to keep on repeating the same laborious and intricate protocols like a robot doing tai chi.  It is boring but it can’t be mindless.  You must be aware of what you are doing to the smallest detail and have the will power to keep doing it without cutting corners.