How To Make Cheese: An Introduction

Learning to make cheese is as much of an art and science as the making of wine. Many factors such as environment, temperature, and certain ingredients all work together to make quality cheese. At the very foundation of the process is curdling milk in order to break it down into curds and whey, the solid and liquid portions of the milk. In order to learn how to make cheese at home, you have to do much more than let the milk sit and go bad. When you make your own cheese, it's a time-consuming process requiring a few additions.

You can make cheese at home from any kind of milk. The most commonly used milk is cow's milk, but sheep and goat milk is also used for some cheeses, like feta or parmesan cheese. You might be surprised to know that real mozzarella cheese comes from water buffalo milk. The first cheeses were simple, nothing more than curds and whey. While people still eat curds and whey today, the varieties of cheese have expanded, with practically each country having its own specialty. Cheese is also divided into two categories, determined by the chosen starter (cultures that help ripen milk).

Mesophilic Cultures: This starter has bacteria that thrive at low temperatures, with room temperature being the best. Cheddar and Gouda are included in this category.

Thermophilic Cultures: This type of starter loves heat and works well for harder cheeses such as Swiss or Italian varieties.

The easiest cheese to make is cottage cheese, where the milk is warmed and left to stand after treatment with a lactic starter. It is probably the closest to the early forms of cheeses mentioned above.

Acidifa-what?

When you make cheese, you start with a process called acidification. This process helps to lower the pH content of the milk and allows certain acids to build up. Bacteria added to the milk eats the lactose in the milk and produces lactic acid as a by-product. The real science in trying to learn how to make cheese at home comes in knowing how much lactic acid is required to make the kind of cheese you want. Too much acid and the cheese becomes hard and crumbly. Too little, and you end up with mush.

Adding Rennet

Rennet is a key ingredient needed to make cheese. Traditionally, rennet was an enzyme taken from the stomach lining of calves. The enzyme chymosin is the one that helps to coagulate the milk. Of course, cheese can be made through the acidification process alone, but you run the risk of making the curd too hard and dry.

The first cheeses were probably made by accident when a person tried to store milk in a bag made from a calf or young goat. The milk would curdle and separate into the curds and whey. Milk spoiled quickly, but through the discovery of how to make cheese, ancient cultures found they could make their dairy products last much longer without spoiling.

Up until a few years ago, calves were the only source of rennet. In 1990, a group of scientists came up with a process of genetic engineering that allowed for a rennet substitute.

These scientists isolated the gene responsible for chymosin and were able to duplicate its properties in a lab. Now, most of the cheese made in the United States comes from this genetically engineered substitute. Rennet comes in tablet or liquid form and is available in forms that contain no animal products, called vegetable rennet. Vegetable rennet is made from the coagulating properties of fig tree bark, nettles, mallow or thistles. This provides a great alternative if you want to make cheese for vegetarians.

Processing the Curd

Once the coagulation has done its job and the curd sets, you can move on to the next step of cutting and pressing the curd. By heating and cutting the curd, the whey is separated further. As the curd heats up, it begins to squeeze out the liquid whey. Removing more moisture will help to harden the curds and depending on what type of cheese you make, you may want more or less moisture. An example of a soft curd is the type of curd you find in cottage cheese, while a harder curd might be the type you find in parmesan cheese that is dry and crumbly.

After the curds have reached the desired hardness, you can start salting and pressing the curds into shape. For this, you will need a cheese press. You can purchase a cheese press at any cheese-making supply store or some people use ceramic crocks or coffee cans. At this stage, salt is added for flavor and to halt the growth of unwanted microbes. As you begin to press the curds together, small curds will join to form larger curds.

Aging Your Cheese

Various cheeses take different amounts of time to age or ripen, and the methods for how to make cheese at home are just as diverse. Everyone will discover his or her own techniques along the way. During the aging process, bacteria is allowed to continue to grow and in some cases, different types of bacteria are introduced to change the flavor, texture and appearance. Penicillium spores are often used when making blue-veined cheese like Roquforte and grow ripe from the inside out. Other cheeses, like Brie, are coated with another type of penicillium that gives the Brie its hallmark white rind. Cheeses like Brie ripen from the outside in.

Cheeses that are surface ripened are either wiped with a bacterial broth or the very atmosphere of the curing room provides the catalyst for creating the rind. This is known as a "washed rind." These washes can consist of everything from salt water to expensive brandy.

Other rinds are created by dipping the cheese in a wax bath or brushing with oil and some cheese is simply left alone and not treated at all. The purpose of the rind is to protect the inside of the cheese while it continues to age. Cheese with a tough outer rind, like some varieties of Swiss cheese, is due to heavy salting, while cheeses like cheddar are barely salted at all and have very little rind.

Of course, this is a very simplistic overview of how to make cheese at home. Learning how to make homemade cheese will take a lot of time and research depending on the types of cheese you want to make. The best advice is to start with a simple cheese. The consensus among seasoned cheese makers is that cottage cheese is the easiest to start with. Soft cheeses come next and after that, the challenging hard cheeses. The more you make cheese, the more you will learn what works and what doesn't. Keep a journal each time you make cheese. Keep track of what ingredients you used, what temperatures and conditions were present with each batch, and how much time was spent at each stage. In time, you will be able to make cheese you can be proud of and keep your guests coming back for more.