The meaning of garde manger has changed over the years. Garde manger (pronounced "gard man-ZHAY") is a French term that roughly translates to "storing/keeping/protecting to eat," and the term originally referred to a pantry or food storage area. Today, it can mean a person or place in the kitchen.
In the modern culinary arts, the term garde manger can refer to the chef who oversees cold food production. Similarly, garde manger can also refer to the specific area of the kitchen where cold food production takes place.
In the classical culinary arts, garde manger refers to a category of foods produced in the cold kitchen as well as the broad array of techniques used for preparing these foods. Some examples:
- Smoked and cured foods
- Salads and salad dressings
- Sausages, pâtés, and terrines
- Pickled foods and condiments
- Cold sauces and soups
Because the tradition of garde manger dates to an age before refrigeration, it encompasses many classical techniques for preparing and preserving foods, such as ballotines and galantines (which are essentially elaborate stuffed chicken leg preparations and, broadly speaking, a form of sausage).
Even before refrigeration, kitchens generally had one area that was constructed to maintain cool temperatures, usually a cellar of some kind. This was particularly true for large ones where the chefs who cooked for royalty and the nobility performed their duties.
Here was where various methods of food preservation were employed, and sometimes invented, whether it was pickling, salting, or air-drying, all in service of the primary goal of preparing and serving food fit for the ruling class of the day.
To understand how it was possible to preserve food using these techniques, it helps to remember that food spoilage is caused by bacteria, which are tiny organisms that require, among other things, food, water, and oxygen to survive and reproduce.
The food for these bacteria is human food, whatever you're trying to stop from going bad. Preserving it thus means employing some method of ridding it of these bacteria, whether by depriving them of air or water or by creating some other condition that renders it inhospitable to these bacteria (temperature and acidity are two additional factors).
For example, confit is a simple preservation technique that works by storing a cooked item such as a duck leg in a container submerged in its own fat. The fat creates an airtight seal, depriving spoilage bacteria of oxygen, and thus preserving the protein item without refrigeration. Note that it's still important to keep confit in a cool location since the fat can turn rancid if exposed to excessive heat.
Cheese-making is also a form of food preservation. Cheese is made by curdling the proteins in milk (either with a live culture or with a mild acid) and then squeezing most of the water out of it, leaving only the protein and fat.
Thus fresh milk, which is itself highly perishable, is transformed into a product that, because it is low in moisture, can be stored for several months in a cool cellar or even a cave.