Biology 12

Chapter 2 Enzymes and Energy • MHR 51

Biology At Work

Cheese Plant Manager

Elaine de Rooy

Elaine de Rooy did not intend to make a full-time career

of her summer job at the cheese factory in Winchester,

Ontario, 60 km south of Ottawa. She had been training

as a medical lab technologist; however, after she

graduated in 1979, she accepted a position in the

factory’s quality control lab. She rose through the ranks,

eventually becoming the plant manager.

Today, the factory where deRooy works processes

250 000 kg of milk into 25 000 kg of cheese annually.

The cheese is shipped to many countries, including the

United States, Great Britain, Japan, Mexico, and

countries in the Caribbean.

De Rooy enjoyed biology as a high-school student, and

she feels that her scientific training is an asset in her

work. She and the medical technologists she has hired

for the lab bring a detailed scientific understanding to

the process of cheese making.

An Ancient Process

Cheese making is a very old craft. At least 6000 years

ago, people discovered that milk curdles in the stomach

of a young mammal. This process occurs in order for

the milk to be digested properly. Bacteria initially curdle

the milk (separate it into solid curds and liquid whey).

Enzymes in the animal’s stomach accelerate this process.

These enzymes, traditionally called rennet, are chymosin

and pepsin.

Dried calf stomachs, called vells, were the traditional

source of enzymes for cheese making. Today, enzymes

from fungi and enzymes made through recombinant DNA

are used to make cheese. Cheese can be made without

using enzymes, but the results (fresh cheeses, such

as cottage cheese) are “unripened” and should be

consumed within a few days. Cheese made using

enzymes can be stored for longer periods of time without

spoiling. According to de Rooy, cheeses made using

rennet obtained from calf stomachs are “a better quality

of cheese for aging.” Around the world, thousands of

varieties of cheese have been developed, depending on

the precise methods and bacteria employed.

Managing a cheese factory makes heavy demands on

de Rooy’s time. The factory operates 24 hours a day,

seven days a week. “If everything is running really well,

you’ve got a really nice mix between home life and work,”

she explains. “When there are problems, it’s a huge

demand on your time. During the past month, I have

been here every day. I have been here in the middle of

the night and gone home to catch a few hours sleep and

come back to work again. That’s my biggest challenge.”

However, de Rooy enjoys solving the variety of problems

she encounters on the job. For instance, any day might

involve dealing with equipment failure, bacteriological

problems, or safety issues.

Career Tips

Managing a factory in the food industry is a multifaceted

job. Managers organize and oversee the work of many

employees. In addition, managers must be aware of what

is involved in each step of producing a product, so they

can ensure production goes according to schedule. This

type of work involves leadership, organizational, social,

and troubleshooting skills.

Select a food industry and research the managerial

challenges specific to that industry, with respect to the

biological processes involved in making the product.