Cheese & Milk Terms Explained

We are bombarded with jargon everyday, all day: at our work, from our friends, from the radio, the television, and the internet. There are many technical and jargon words used in the dairy and cheese industry, which are actually useful to communicate a particular significant fact regarding a dairy product. We receive a lot of questions everyday here at Boston Cheese Cellar, so we have gathered a few of the major culprits of confusion here, and broken them down for you!

A wonderful resource, if you want to delve further is the Oxford Companion to Cheese, of which we have a copy in the shop for you to enjoy.

Acid or Acidity: A measure of the level of free and potentially reactive hydrogen atoms (H+) within a liquid. This is important in cheesemaking as it influences the quality/texture/malleability of the curd, as well as acting as a preservative (more acid, less spoilage). High levels of acidity can provide crumbliness to a cheese, whereas mozzarella requires an exact level to be stretched. Acidity is measured in pH units, the lower the pH, the more acid. Neutral is 7.0.

Affinage & Affineur: The process of, and person in charge of, the controlled ageing of cheese.

Ageing: The process by which cheese develops its flavor through microbial action on the proteins, sugars, and other the molecules in the cheese.

Alpine: One of the 'genre' of cheeses, that we use in the shop to classify cheese. Alpine style cheeses share a common method of make resulting in similar texture and taste, these include: a high temperature treatment of the curds to drive out moisture, low salt content, common microbiota, the final shape often being a large-squashed disc (which a large surface area to volume ratio). Initially made in the Swiss & French Alps, hence the name. Examples are Emmental, Gruyère and Comté.

Blue: Another of our 'genres' in the shop classification system. Cheese which intentionally contains blue moulds (e.g. Penicillium roquefortii or Penicillium glaucum)

Cheddar: A cheese made using a step called 'Cheddaring' where blocks of curd are stacked on top each other where heat and pressure help to drive out whey.

Curd: Rennet action on milk, produces a large single jello-like block of a network of casein molecules, entrapping water, fats, minerals etc. This is called a coagulum or junket. Once the coagulum is cut, the entrapped liquid is released, called whey, and the solid remaining is the curd.

Homogenized Milk: Milk which is treated by forcing through a very small apperture, breaking large fat globules in the milk into smaller, more even (homogenous) ones. This helps to prevent the cream/large fat globules clumping and floating to the top of milk (partitioning). Homogenization also disrupts the cryoglobulin proteins which aid this clumping process.

Lactose: The milk sugar, lactose, is the only sugar found in milk. It can cause digestive issues in man, including bloating and discomfort. As newborns, we have the ability to breakdown lactose through the production of a protein called lactose dehydrogenase. Many western europeans contain a mutation in within this gene, which allows it to function throughout our adult life. Without this mutation we lose the metabolic ability and excess lactose metabolism by bacteria (not us!) causes these uncomfortable feelings. Lactose is continuously metabolized in cheese during ageing, and is regarded as having reached minimal levels at 1 year. Therefore if you are lactose intolerant, try cheese that is aged greater than 1 year. Milk from goats, cows and sheep does not vary significantly in its lactose content.

Microbes: The general name for microscopic organisms, which include bacteria, yeasts, fungi and moulds. They can be beneficial or dangerous (pathogenic). Many microbes are integral to cheese making, either by acidification of the milk during the initial stages (e.g. lactococci), or by being critical to to the ageing process (e.g. penicillium roqufortii, or lactobacillus helveticus).

Mold: Either a filamentous fungi (microbe), or a shape which holds curds during cheesemaking.

Pasteurized Cheese: After milking, the milk undergoes the process of pasteurization - it is heated to 161 F for 15 s and cooled rapidly. This has been shown to eliminate Staphylococcus aureus, Escherichia coli., Lysteria monocytogenes, etc. and is therefore used to cleanse milk of potentially dangerous microbes. This is why pasteurized cheese is recommended for those with weakened immune systems (pregnant women, the elderly, the very young and those undergoing cancer treatment). However, this step does not distinguish between good and bad microbes, and therefore those which may contribute to flavor are also lost. To provide flavor development during ageing, cheesemakers add their own mix of desired microbes to the milk after pasteurization.

PDO/DOP/AOC/PGI: These various designations recognised by the World Trade Organisation and European Union, provide protection for types of cheeses, that are made either in specific regions (e.g. Stilton, Brie) or by specific methods of manufacture (e.g. Brie, Taleggio, Comté).

Raw Cheese: Milk that has come directly from the cow, with the only step of cooling for storage is called Raw Milk and can be used to make cheese. The raw milk contains microbes from the environment where the cow/goat/sheep grazed, and therefore raw milk cheese will be a reflection of that environment. In the United States, raw milk cheeses must have been aged for a minimum of 60 days to be sold. State laws vary regarding the purchase of raw milk.

Rennet: The substance which transforms milk into a solid network of curd, which further processed will become cheese. Traditional rennet is a paste of a variety of enzymes isolated from calf or lamb stomachs. Vegetarian rennet is a single enzyme (chymotrypsin) and is sourced from laboratory cultures of bacteria - where no animals are harmed. Some 'rennet' can be isolated directly from plants. Soft Bloomy: A cheese with a soft, fluffy white rind, e.g. Brie, Camembert, Brebirousse. Another classification 'genre'.

Terroir: The flavor of a local environment, passed through the milk of the cow/goat/sheep and into cheese. This will be dependent on the presence of original microbes (requiring raw milk), but will also have contributions from organic flavor compounds in the grass the cow/sheep/goat grazed on (which will still be found in pasteurized milk). Thermized: A mid-way point in-between pasteurized and raw milk, where milk is heated between 141-145F for 15s. This destroys many bacteria which can survive under refrigeration (such as Lysteria), but leaves many others untouched. In the USA, thermized milk is regarded as raw!

Rind: The outer layer of a cheese, which can be of many textures, colours, flavours etc. Edible, unless it is made of wax.

UHT Milk: Ultra-Heat Treated milk is pasteurized to extreme levels, where the milk is held at 284 F for 4 seconds. This destroys all microbes, prolonging shelf life of milk considerably, however, it also destroys the protein required to make cheese. UHT milk, can therefore not be used to make cheese!

Washed Rind: Another 'genre' of cheese we use to classify the cheese in the shop. The outer surface of a cheese, that has been washed with a bacterial and brine or alcohol-based liquid. This encourages particular microbes to grow on the rind to produce flavor.

Whey: The liquid release once a coagulum or junket black has been cut into curd.

Yogurt: Milk is heated to destroy the milk proteins, and then microbes are added to allow them to work on the sugars in milk, to acidify the mix. This acid causes the denatured milk proteins to randomly clump together, rather than forming organised curds, as in cheese.

Want to learn more? Come to Boston Cheese Cellar to hear more, or attend one of our Cheesemaking classes where we delve deeper into such topics!