The group after Jon defended his honors thesis and right before all the seniors represented chemistry and biochemistry at multi disciplinary poster session celebrating experiential learning and the Boundless campaign.
From our seniors…
Amen Taye (’25)
“…one of the most important things I learned was how much I’ve grown both personally and professionally through my time in the lab. While applying for jobs, I found that most of my interview answers, whether personal or professional, were based on my experiences here. The lab gave me a chance to build both hard and soft skills that are highly transferable, and it helped me realize how far I’ve come from having minimal experience to gaining real confidence in myself as a scientist.
While the science itself wasn’t necessarily new to me this semester, I believe I refined my technical and troubleshooting abilities by engaging with the challenges my mentees faced. This mentoring experience not only shaped my semester but also taught me meaningful life skills that I’ll carry forward
…you can do anything so long as you put your mind to it and are willing to put in the work.
She has pushed me to accomplish more than I believed possible in two and a half years.
The Colabroy Lab Spring 2025
We will miss Jon (who heads off to Cornell for a PhD), Bernice (heading off to Virginia Tech for a PhD), Amen (joining a clinical research group at U Penn) and Or-El (joining a clinical trials team in Boston).
The supporting material – including guided inquiry activities and laboratory exercises for the second edition of The Science of Cooking by Provost, Colabroy, Kelly, Corrigan-Steffey and Wallert can be found HERE.
In Summer 2020, I worked with five students remotely. It’s hard to do chemistry remotely. But we did our best. Here are their presentations from the Celebration of Student Research and Scholarship in October 2020. I’m so proud of what we managed to accomplish. Alex and Miranda’s work spanned more than just the summer, since they are seniors now. But David’s work really contributed to the publication I’m writing, and Paige and Snow’s work became part of BCM 341: Experimental Biochemistry in Fall 2020.
Raw milk mozzarella (Flint Hill Farms, Coopersburg, PA)
This raw milk mozzarella was made using 1 gallon of raw, whole cow’s milk, 1/4 of a vegetable rennet tablet, and 1.5 tsp of citric acid. I used bottled water to dissolve the rennet and citric acid.
Something that I did (without realizing it) was crush the rennet tablet between wax paper with the flat side of my knife. Then I slid the powdered tablet off the wax paper and into the water. This made the rennet easy to disperse in the solution, and it was clearly working. The curds obviously formed between 20-30 seconds and were thick enough to resist the spoon.
Milk + citric acid reaches 90 degrees, and I add the rennet. After a slow 30 seconds of stirring the rennet, the curds are resisting the spoon
After standing, 5 min, removed from the heat. Curds have cleared pulled away from the sides of the pot
After cutting the curds, I stirred gently and heated to 105 degrees. Curds clump together in the center of the pot
Heat to 105 degrees
After the pot reached 105 degrees, stirred for 5 minutes off the heat, then scooped curds into bowl. Temp is around 100 degrees
Before microwaving
After microwaving for 1 minute. More whey is released.
Drained off some of the excess whey into the sink
Pressed curds with gloved hands to drain whey
Temp is around 123 degrees
Microwaved in 10-20 second bursts, until 135 degrees was reached
Streched curds by shaping into a ball
The curds were hot and easily stretched.
During stretching and shaping, the curds became glossy
Continued folding and smoothing into a ball.
The entire stretching and shaping process took 30-60 seconds. Shaped ball was still very warm.
Pasteurized “Whole” Milk Mozzarella
I used the same technique in which I crushed the rennet tablet with the flat side of my knife between a folded piece of wax paper. The rennet and citric acid were the same as above. I had only 1/2 gallon of pasteurized whole milk, so I used another 1/2 gallon of 2% pasteurized milk for 1 gallon total.
Added citric acid and gently stirred milk until it reached 90 degrees
Removed milk from heat, and added rennet. Stirred for a slow 30 seconds. Noticeable curd formation by 20 seconds, and by 30 seconds the curds were resisting the spoon.
After sitting for 5 minutes, off the heat, lid on. Notice the curds are not as tightly formed compared to the raw milk curds above
After cutting the curds, I stirred them very gently and slowly on the heat to reach 105 degrees. I didn’t realize it, but my thermometer was poorly placed, and the mixture got hotter than I intended…closer to 120 degrees.
I spooned out the curds. They are smaller clumps than the raw milk curds above.
The whey after straining out the curds. The whey is “clearer” and more yellow than the whey from the raw milk.
The strained curds are warmer than I intended. When I did this for the raw milk, the curds were around 100 degrees at this point.
I heated for 20 seconds only (rather than 1 minute) to get the curds close to ~120-125 degrees. I strained the excess whey into the sink. The curds are stiffer and smaller than the raw milk curds. I choose this time and temperature because I was heating the curds to match the temp I got for the raw milk curds (after I heated those for 1 minute)
The curds are about 114 degrees at this point. I need to heat to 135 degrees for stretching
Microwaving for 20 seconds gets the curds to 135 degrees (after a few seconds of waiting for the temp to stabilize)
I folded the hot curds over and over. They are looser, and required more work to make them stiffen and become glossy.
As the curds stiffened, I was able to shape into a ball. The curds are less stretchy than the raw milk curds. The entire stretching and shaping process takes 30-60 seconds.
In both pieces, “War” and Coffee Poems the color of the coffee is significant. The Coffee Poems talk about coffee’s blackness, with the color of ink. It is contrasted with milk by color, but not in meaning – the authors imply that milk and coffee share the same “purity” – in fact, the color is the seal of its purity. In War, there is an extensive discussion about the use of milk to turn coffee brown – the exact color of a monk’s robe. The exact color is known only to a select few who must know in their mind the brownness of the robe, and match the color by balancing the amount of milk against the strength of the brew. We might expect the authors of coffee poems to find the kapuziner impure. In War, Allen tells the reader that Turks believed milk added to coffee caused leprosy.
What is interesting here is not the presence of milk, but rather the appeal to coffee’s color. The coffee poems appeal to the blackness of the coffee as evidence of its purity – and by implication, its holiness. The writers of coffee poems imply the purity of the coffee imparts God’s favor or blessing – the drinker also experiences enlightment, by the pursuit of wisdom. The addition of the milk to make the coffee brown in the kapuziner would therefore be an adulteration of the beverage. And yet, being able to make the kapuziner is evidence of one’s depth of knowledge of Vienna’s coffee culture – you have to know the exact color of the monk’s robe. So in the case of the kapuziner, the knowledge was required to change the coffee’s color. The enlightenment (or state of enlightment) of the coffee drinker/brewer is significant.
Certainly Balzac (The Pleasure and Pains of Coffee) would have been delighted to read “Eight Cups a Day” (Johnson, NYTimes, 2008). Balzac was a writer made legendary for the sheer quantity of writing he produced in his lifetime; productivity fueled perhaps by his obsession with coffee.
In reading the two pieces, written over 100 years apart, I was first intrigued by the number of references to human anatomy. For example, in “Eight cups a day” we read of cardiovascular difficulties, lowering of the risk for atherosclerosis and the cerebral infarction – all medical terms associated with the heart and the brain. Balzac too mentions the diaphragm, and the plexus of the stomach, and also the brain(x2)/cerebral. He addresses the stomach (x2) filled with suckers and papillaeand its digestive juices. Between all these anatomical references, the brain/cerebral is repeated most often.
Interestingly, the physical and anatomical would seem opposed to the spiritual. Something spiritual is intangible, while a brain or a stomach is certainly not. In “Eight Cups a Day”, we find a reference to mydemon and Satanic worship – both written in reference to coffee’s effect on the author and other drinkers. In Balzac, “few writers are actually becoming more spiritual” (P1), while coffee effects on the stomach are as a “pythoness appeals to her god”. Apythoness is a female priestess or practioner of divination. Finally, at the end – the coffee drinker is referred to as a “man of spirit” – implying that the presence of spirit is evidence of coffee drinking. In these reference, it would seem that the evidence of the spirit/spiritual/possession is a result of the coffee drinking – something so physical, the act of drinking, producing measurable biological effects that are simultaneously spiritual/non-physical.
Perhaps the reference to the spiritual or the intangible is implying the intangibility of the ideas themselves. The ideas are a product of the coffee drinking, after the pythoness appeals to her godBalzac does find sparks shooting up to his brain. But this is not consistent with “Eight Cups a Day” where the author abstains from coffee and is able to function “just about normally again” – apparently recovering from his “sluggish brain.” Was the author able to generate ideas without the coffee? It would seem so…
And yet the author of “Eight Cups a Day” refers to the coffee as “my demon”, while Balzac’s pythoness appeals to her god. Who is her god? If the pythoness is conjuring spirits from her god, then “she” is conjuring spirit from Balzac himself. Balzac and Johnson (“Eight Cups a Day”) are both the gods and coffee is doing their bidding. And perhaps in the mystery inherently associated with these kinds of intangible words – demon, spirit, god – these authors are pointing to the invisible science that turns stomach acid, blood, nerves and brain matter into words, sentences and ideas.
Certainly Balzac (The Pleasure and Pains of Coffee) would have been delighted to read “Eight Cups a Day” (Johnson, NYTimes, 2008). Balzac was a writer made legendary for the sheer quantity of writing he produced in his lifetime; productivity fueled perhaps by his obsession with coffee.