Bringing food chemistry to life

So far this summer I have given two short workshops using wheat, flour, bread,  and baking as a way of bringing food chemistry to life.

The First group was the

Oregon Farm Bureau’s  Summer Agriculture Institute

on the theme of Grain-Gluten-and Great bread. And started with the quote from Henri Fabre a 19th C French entomologist.

“History celebrates the battlefields whereon we meet our death,
but scorns to speak of the plowed fields whereby we thrive;
it knows the names of kings’ bastards
but cannot tell us the origin of wheat”.

We worked through H.E. Jacob’s “Rivalry of the grasses” from “6000 Years of Bread” on the theme that wheat was ascendant partly because it made risen products with palatable textures as a result of the unique properties of gluten proteins [their stubborn insolubility, the ability of the large glutenin molecules to cross-link into enormous (by molecular standards) elastic networks, and the viscous contribution of the gliadins leading to the viscoelasticity of wheat flour dough].

We looked at the fracture properties of grain during milling and how these are related to a single gene that determines if wheat kernels are soft or hard. Then through the genetics of gluten diversity and finally to experiencing some of this in breads and doughs. it was a lot of fun, and we had great bread to eat as well.

The Second Event was the…

Apprenticeships in Science & Engineering (ASE) Mid-Summer Conference

workshop for high school juniors and seniors.

This year we went with the TSoB (the science of baking) workshop again. But this time enhanced with hands-on dough mixing, and sprinkles of…

Polymer chemistry – dough and gluten properties
Physical chemistry – dough hydration and mixing
Physics/Rheology – fracture mechanics in milling, dough properties, bread texture
Organic chemistry – Maillard browning reactions
Physics – the gas laws & rising bread
Biochemistry – fermentation
& Genetics

All the students were remarkably engaged with the topic, helped along by a bribe of very fresh baguettes. The teachable moments were abundant but it seemed the most effective were;

-to experience the relationship between weak and strong dough and dough elasticity by rolling out dough  by hand.

-to hand mix a dough from scratch and to experience the rate of hydration and to feel gluten devlopment and to get to understand why we need air in dough (an aqueous phase saturated in CO2 cannot spontaneously create gas bubbles, they need to be prenucleated in the dough).

-to experience the relationship between water activity and crust browning.

We had a lot of fun and are looking forward to next year.

I don’t have clearance yet to show faces, but even the hands tell a great story about student engagement !

We have one more workshop planned this summer for the K-12 science and math teachers of Lincoln County Oregon.