Case Study 2 — The Knowledge Transfer

Setting

A Tuesday afternoon in early May. Three different rooms, three different people, three different versions of the same scene — each one a moment of teaching. The subject of the case study is not any one of them. The subject is the pattern.

This is what a book wants to do, in the end: travel through hands. The book itself is finite. The teaching is not. We follow three short scenes from one week, in three different places, where someone is teaching something they learned from this book — or from books like it, or from cooks like Aroon — to someone else.

The scenes are: Pat Hammond's chemistry classroom in rural Ohio; Aroon Sornprasit's restaurant kitchen in Toronto, where Danny is wrapping up his apprenticeship; and a small community kitchen in a Boston public library, where a volunteer named Esther is running her weekly Tuesday cooking class for retired adults.

Scene 1: Pat's Classroom

Pat is in front of twenty-six AP Chemistry students. There is a hot plate on the front bench. There is a small saucepan. There is a candy thermometer. There are six small bowls of granulated sugar. There is, on the whiteboard behind her, a blank chart with two columns labeled "TEMPERATURE" and "WHAT HAPPENS." Underneath the chart she has written, in marker: the candy stage ladder.

This is the lesson. Each pair of students will heat a small amount of sugar in water, with the candy thermometer in the pot, and call out to the class as the temperature rises through each candy stage — soft ball, firm ball, hard ball, soft crack, hard crack. As each stage is reached, Pat will pause the demo, drop a small amount of the syrup into a glass of cold water, and let the students see what each stage looks like in the cold-water test. The students will fill in the chart from observation.

The point of the lesson is the stages themselves — yes — but the deeper point is that the same chemical (sucrose) goes through a series of very different physical states as it loses water and accumulates concentration, and that each physical state corresponds to a kind of candy: fudge at one stage, taffy at another, brittle at a third. The lesson is that physical chemistry is visible if you know how to look for it.

A student named Marcus, who has so far this year been polite but not engaged, is paired with a student named Aliya. They run their pot. The temperature climbs. Marcus is calling out the readings. Aliya has the dropper. At 250°F (121°C), Aliya drops a small amount of syrup into cold water; it forms a firm ball. Marcus walks up to the front of the room and uses his fingers to roll the cooled drop. He says, with surprise: this is fudge.

Pat smiles. She says: that's right. That's exactly fudge texture. That's why the recipe says cook to 240°F (115°C) — soft ball — for fudge. If you go ten degrees too hot, you've got something that's too firm. The chemistry of the syrup decided what kind of candy you were going to get, and the temperature is what tells you which chemistry you're in.

Marcus, walking back to his bench, says — and Pat will tell me this story months later, because this is the moment that made the lesson work — so candy is just sugar at different temperatures. That's it.

Pat says: that's it. The syrup goes through every state of candy on its way up the temperature scale. You stop where you want to be. The candy ladder is the most underrated chart in chemistry.

Aliya, beside Marcus, says: we should make brittle.

Pat says: next class. Bring patience.

Six students stay after class to ask Pat where to read more about it. Pat hands them a list. The list includes this book. The list also includes Harold McGee's On Food and Cooking and Stella Parks's BraveTart. Pat does not promise that any of these will make them cook better. She promises that, if they are interested, the books will tell them what was really happening in the pot.

This is the scene of a chemistry teacher doing what chemistry teachers can do at their best: opening the door, naming the science, handing forward the references. Pat will retire in three years. Some of her students will go into nursing, some into trades, some into technical jobs of various kinds. They will not become food scientists. But they will, for the rest of their lives, understand the pot of sugar. And if they ever try to make fudge, they will know to stop at soft ball. And if their fudge fails, they will know what went wrong.

Pat's notebook of demos is, at this point, the size of a phone book. She is going to leave it to the chemistry teacher who replaces her. The notebook is, in some way, her version of what this book is — a transmission of the knowledge that food is the entry point. She has been telling teachers for twenty-eight years that the kids who think they hate chemistry love the kitchen lab. She has been right every time. The notebook is the proof.

Scene 2: Aroon's Kitchen

Across the border and seven hundred miles to the north, Aroon Sornprasit is in the kitchen of Mae Som on a Tuesday afternoon. The restaurant is not yet open for service. The line cooks are prepping. Danny Reyes-Park, in the second-to-last day of his two-week apprenticeship, is on the salad station, doing what Aroon told him to do this morning, which is making yam neua — Thai grilled-beef salad — by feel, without his thermometer.

Danny has the steak on the charcoal grill in the back. The grill is the small Japanese-style charcoal grill Aroon prefers for steak; the coals are at the temperature Aroon trusts (about 260–290°C / 500–550°F at the cooking surface, but Aroon does not say this). Aroon is over by the prep counter, slicing herbs. Danny is watching the steak. The steak has been on the grill for two and a half minutes. He flips it. He waits another two minutes. He picks it up with tongs and presses the back of it with a finger.

The press, in classical chef training (the touch test), is one of the most contested techniques in cooking. The idea is that you can match the firmness of the steak to the firmness of different parts of your hand to estimate doneness — touch your thumb to your index finger, the firmness at the base of the thumb is rare; thumb to middle finger is medium-rare; thumb to ring finger is medium; thumb to pinky is well-done. Some chefs swear by this. Others say it is unreliable, that the firmness depends on the cut and the cook, and that the only honest way to know is the thermometer.

Danny has been thinking about this for two weeks. He has watched Aroon do the touch test. He has done the touch test himself on every steak that has come off the grill, and then immediately checked the temperature with a probe to see if the touch test was right. After ten days, his touch tests are within two or three degrees of the probe readings. The technique works for him. He has been, in some sense, calibrating his own hand against the thermometer the way you might calibrate a measuring device against a gauge.

Today the steak is off the grill. Danny presses it. He says, to no one in particular: fifty-four. Maybe fifty-five.

He puts the probe in. The probe says 55°C (131°F).

Aroon, from the prep counter, has not looked up. He says: correct.

Danny puts the steak on the rack to rest. He has, by Aroon's standard, just done what Aroon does. He has a thermometer and he can use it; he also has a hand, and the hand is now telling him the same thing the thermometer is, because the thermometer trained the hand. The hand and the thermometer are not in opposition. The hand is what the thermometer becomes after enough years.

Aroon walks over. He looks at the steak on the rack. He says: good. You did it without the probe.

Danny says: I did it with the probe yesterday. The probe was teaching my hand.

Aroon says: that is right. That is the whole game. The science gives you the gauge; the gauge calibrates the hand; the hand is what cooks the food. Twenty years from now, you will be teaching some kid the touch test, and the kid will think you have a magic finger, and the magic finger will be the thermometer that you put down ten years ago.

Danny laughs. He says: I want to remember to tell the kid the truth.

Aroon says: good. Tell the kid. Most chefs do not tell the kid.

He goes back to the prep counter. The salad station gets busy. The dinner service starts. The steak goes out to the dining room as part of a table's order, and a customer who has been eating at Mae Som for years sends back the compliment that the yam neua tonight is exactly the way she remembers it.

Danny, in the back of the kitchen washing his hands at the end of the night, has a moment of recognition. The science was what taught his hand. Aroon's grandmother was the same hand, three generations earlier, taught by her hand-with-experience, which was itself the science working without being named. The lineage is the same lineage. The science is the named version of what was always being passed down. Danny is going to open a restaurant in five years; he is going to teach line cooks; he is going to use the thermometer with them and then put it down with them. The whole thing is one continuous transmission.

This is what Aroon has been doing across the entire span of this book. He has been demonstrating that the science is the naming of what cooks have always known. The lineage is older than the names. The names just make it easier to teach.

Scene 3: Esther's Library Class

In the basement of the Brighton Branch Library in Boston, in a small kitchen that the library renovated three years ago through a community grant, a woman named Esther Quintanilla is running her weekly Tuesday cooking class. Esther is sixty-one. She is not a chef. She is a retired nurse who, after her husband died four years ago, started cooking from the boredom of being alone in the house. The first books she read were the food chemistry books that started showing up at her local library — including, eventually, this one. She has, over four years, gone from a person who knew nothing about cooking to a person who runs a free weekly class for other people in her neighborhood, most of whom are also retired, most of whom are also widowed or divorced or living alone.

The class today is eggs. Six attendees. The youngest is fifty-five; the oldest is eighty-two. Esther has set up the kitchen so each person has a small saucepan, a couple of eggs, salt, a thermometer, and a pad of paper. The lesson she is teaching is the Chapter 14 lesson: that the egg, cooked at different temperatures, gives you different egg dishes, and that the temperature you stop at is the difference between a runny soft-boil and a chalky over-boil.

Esther says: the egg white starts to set at 62°C (144°F). The yolk starts to thicken at 65°C (149°F). The yolk fully sets at 70°C (158°F). If you take the egg out at 64°C, the yolk will be runny and the white will be just set. If you take it out at 75°C, the yolk will be hard. You can pick. The thermometer tells you exactly where you are.

A man named Pierre, who is eighty-two, says: I have been making eggs for sixty years. I never had a thermometer.

Esther says: and you make them well, I bet.

Pierre says: well enough. But I cannot tell anyone how to do it.

Esther says: that is why we have the thermometer. The thermometer is for explaining. Once you can explain, the next person can learn faster.

Pierre says: who am I going to teach?

Esther says: your granddaughter, when she comes over this weekend. She is twelve. She has never made an egg.

Pierre is silent for a moment. Then he says, with sudden interest: I have a thermometer at home. I never used it.

Esther says: you will use it on Saturday.

The class continues. People run their eggs through a low-temperature water bath, take them out at chosen temperatures, crack them open on plates, and observe the results. Each person makes the egg they like — Pierre prefers a hard yolk, two of the women prefer a runny yolk with a set white, one woman prefers a fully soft-poached egg that flops out of the shell. Each person now knows the temperature that produces the egg they like, written down on the pad of paper.

Esther tells me, when I ask her about the class, that the most important thing the class does is not the cooking. The most important thing is that the people in the class feel capable. They are people who are alone more than they used to be, who often eat alone, who often eat the same thing they always have, and who feel, sometimes, that they are no longer learning anything. The class is a class about learning something. The food is the vehicle. The capability is the gift.

Esther says: they leave feeling like they did something. The eggs are good. But the more important thing is, they wrote down the temperature they like, and they will go home and make that egg again, and they will be able to tell their grandchildren about the temperature. The science is what makes the teaching possible. Without the science, the egg is just an egg. With the science, the egg is something I can teach to a person who has eaten eggs for eighty-two years and never had a way to talk about them.

What the Three Scenes Have in Common

The three scenes are different in every detail. A high-school chemistry class in Ohio. A Thai restaurant in Toronto. A library cooking class for retired adults in Boston. Different ages, different cuisines, different teachers, different students. The lesson in each scene is different (sugar stages, steak temperatures, egg temperatures). The relationship between teacher and student is different (institutional in Pat's case, mentor-apprentice in Aroon's, peer-led in Esther's).

But every scene is the same scene at a deeper level. In each scene, one person who has come to understand something is making it possible for another person to understand it too. The medium of the transmission is the science, which has names for what is happening and which can therefore be taught. The content of the transmission is the practice — the actual cooking, the actual hands, the actual food that comes out at the end. Both the science and the practice are necessary; neither is sufficient alone.

This is what a working food culture looks like. Not a stack of cookbooks. Not a collection of restaurants. Not a list of ingredients. A transmission — between generations, between traditions, between strangers who happen to be in the same kitchen — of the knowledge of how to feed people well. The transmission has been happening for as long as humans have cooked. It has been happening, until very recently, mostly without science vocabulary. The vocabulary is new. The transmission is old.

What is new — and what this book has been trying to add to — is the speed of the transmission when the science is named. Pierre, after sixty years, can tell his granddaughter about the egg temperature on Saturday in a way he could not have told her last week. Marcus, after one chemistry class, knows the candy ladder. Danny, after two weeks of apprenticeship, can call the temperature of a steak by feel. None of these accelerations would have been possible without the science. None of them replaces the years of practice. They seed the practice. The practice grows from there.

This is the case the book is making, across all forty chapters: the science is not in tension with the cooking. The science is the language in which the cooking can be more rapidly taught. Every cook who can read this book is a node in a transmission network older than recorded history. The book is a small contribution to the network. Your cooking, after the book, will be a larger contribution.

Analyze This

Pick one of the three scenes and answer:

1. What is the transmission, in chemistry terms? (Identify the specific reactions, processes, or principles being taught.)

2. What was the teacher's role, beyond presenting information? (Pat is not just lecturing; Aroon is not just demonstrating; Esther is not just leading. What is each one actually doing?)

3. Where did the teacher acquire what they are teaching? (Trace the chain back as far as you can — the teacher's teacher, that teacher's tradition, the science behind it.)

4. What does the student do with what they receive? (Knowledge that is received and not used does not transmit further. Predict what each student will do next.)

5. In your own life, who are you the teacher to, and who is your teacher? (Be honest. Many people, especially in a culture where cooking is delegated to professionals, are not in active teacher-or-student relationships around food. If this is you, name it. The first step in joining the network is noticing you are not in it yet.)

Optional, for the reader who wants to write: pick yourself and write a fourth scene. Where, in the next year, will you be teaching what you have learned from this book? Who is the student? What is the lesson? What is the food?

The answer is the assignment for the rest of your cooking life.