Can’t show the students for administrative reasons, but we had a good and educational time once again.
Bringing you highlights from the second iteration of “BRINGING FOOD CHEMISTRY TO LIFE”.
Mayonnaise and egg white foams, and ways of messing them up that were instructive for the chemistry lesson.
Using the Brookfield viscometer to show how viscosity changes with molecular weight @ equivalent w/w concentration, and how it changes with w/w concentration @ equivalent molecular weight. The Brookfield with the helipath stand was also good for demonstrating how the viscosity of the mayonnaise decreased with increasing shear rate [shear thinning]. The helipath stand makes sure the sensor is going through an as yet unsheared region, taking time-dependent thixotropic behaviors largely out of play.
Fun with spherification whilst experiencing the gel forming capabilities of biopolymers with different gelling mechanisms [alginates, glucomannans, methylcellulose].
COFFEE WEEK: browning reactions, & foam and emulsion production and stability in espresso as related to roast degree [and therefore the interplay between arabinogalactan peptide, and maybe galactomannan, extractability [during hot water extraction] and thermal degradation [during roasting] in determining the stability of the espresso crema]
Prepared for a cupping [monsooned, versus washed arabicas, versus robusta]
Color versus roast degree via tri-stimulus color meter.
How fun to have an espresso machine as part of the lab equipment! And coffee roasters too.
The instructor/barista hard at “work”
STARCH WEEK: not just formal viscometric studies, but also hands on experience of the different gelatinization temperatures and pasting behaviors of a variety of starches [e.g. potato versus wheat].
The instructor/starchista hard at work.
Using freshly made noodles as a way of bringing to life the profound functional influence of differences in starch amylose content on food texture.
MEAT WEEK: As a plant scientist I find this work really hard to clean up because of all the fats!