Don’t worry you won’t have to erase your search history or be put on an FBI watchlist for renting out the anarchists cookbook, this simply refers to the chemistry we often take for granted in our very own homes.
That said lets jump right into it.
As we stated yesterday cooking is chemistry, everyone who is in their kitchen cooking is technically a chemist in a laboratory. Cooking uses heat to produce chemical reactions between food molecules and subsequently other molecules within the food which in turn give the food new properties such as changing its flavor, smell, color, consistency, nutrition and even toxicity.
When we cook food the changes that occur as a result of heating can be referred to as the ‘chemistry of cooking’. Heat causes many of the complex molecules in food to breakdown into smaller molecules, some of these are important as we covered yesterday, enhancing our ability to think by shortening time for digestion.
For example tough proteins in meat are broken down during cooking into more digestible forms and the heating of the meat also facilitates the occurrence of reactions between the food and the chemicals, some of these reactions have names such as the Maillard reaction as well as caramelization.
We will now delve into some of these reactions, their origins and their uses.
The Maillard Reaction
Louis Camille Maillard ( 1878-1936 ), a French chemist who in 1912 found that if enough heat is applied two of the vital components of food, that is to say two of the most important building blocks for what we now consider everyday eating, proteins and carbohydrates, react together producing a distinctive new set of molecules these new models give some cooked foods their flavors, scents and colors.
Caramelization also occurs in much the same way when the reaction between molecules and heat is applied. Caramelization basically refers to a de-hydration reaction where water molecules are driven off from sugars thus converting them into new forms of sugars and eventually producing the sensation of flavor, smell and color.
The Maillard Reaction and Caramelization work together to produce the distinctive flavors, smells and colors of the cooked foods that we know and love today, many things ranging from something as simple as freshly toasted bread to a well done steak , roasted coffee beans and even popcorn. So why do we as humans find these tastes and scents so alluring?
Not to mention the incredibly fragrant aromas that can often lure one unsuspectingly into a new diner or restaurant simply led by our nostrils?
The key to this is chemistry.
Among the chemicals released during cooking many scent molecules similar to those given off buy fruit once it has been ripened, one which we can all attest to, given that it appealed to our ape-like ancestors as an energy-rich source of sugars which made up a vital component of their diet. .
Fruits probably provided our evolutionary ancestors with refreshing sensory interludes in an otherwise bland and dull diet …. perhaps cooking with fire most valued in part because it transformed blandness into fruit like richness.Harold McGee
Now we shall explore Yeast.
Anyone who’s spent enough time in the kitchen knows that not necessarily all cooking needs to involve heat, for example the kneading of dough in the initial stages of bread making is a great example of the mechanical alteration of the chemistry of food. The kneading action itself elicits a reaction from the proteins present in dough, proteins such as gluten, to align and cross-link to form long elastic-like chains which in turn allowed the dough to rise by trapping the gas produced by the action of yeast.
So what exactly is Yeast?
It can be defined as a fungal micro-organism that converts sugar into ethanol, a type of alcohol, a process which gives off carbon dioxide and which produces the reaction known as fermentation, generally in baking the alcohol is a side product and it’s mostly driven off during baking but fermentation as anyone who drinks beer would know, is a process in itself, and the basis of brewing .
We cannot truly be sure when we as mankind first harnessed the incredibly remarkable properties and chemical abilities of Yeast, many assume it was pre-historic man but like most records they have been white-washed and we cannot truly be sure of how influential non-white civilizations where on these processes given that many of our historical records were destroyed during subsequent invasions of our homelands. According to our common era (CE) history the first records of brewing come from ancient Mesopotamia around the year 4000 BCE, which for those who don’t know stands for Before Common Era ( as a substitute to the more commonly but increasingly less popular BC and AD ), we are also aware that beer was brewed in a pre-dynastic Egypt more or less around the same time. We are aware of this because it was produced in such large quantities as to be made available for export, which in turn makes brewing one of the earliest forms of industrial chemistry.
Where does the word chemistry come from?
From what we know of our current historical records the word chemistry has its roots in the word alchemy which in turn is a western pronunciation of the Arabic word al-kimiya, however the origins of the root word kimya vary according to sources. Philosophers such as the Roman Pliny The Elder initially claimed it derived from the ancient Egyptian kemi which means ‘black’, a reference to the black silt of the extremely fertile Nile River, the first matter in the Egyptian cosmology and the name given to Egypt itself and thus by extension to the Egyptian art. Yet another alternate history is that it was said to be derived from the Greek word khemeia which roughly translates to “pour together” a reference to the fusion of molten metals.
Thus concludes todays article on kitchen chemistry, I will be delving further into this subject as time goes on so stay tuned for that and don’t forget to leave a comment and follow my blog to receive updates on the latest posts.