Glossary

Virus of the bacterial culture for the cheese.

Biochemical oxygen demand (BOD) is the amount of dissolved oxygen used by microorganisms to break down organic matter, like sewage, in water. BOD is increased by the amount of sewage and pollution in the body of water. A high BOD causes less oxygen to be available to higher animals like fish because it is being used up by microorganisms. Treating wastewater is one way to lower BOD.

Whey drainage that occurs in forms.

Shoveling pieces of cheese curds to one side of a curd table.

A substance that is able to speed up reactions in organisms.

Small curd particles that are not recovered in the cheese.

Can break down fats.

The act of cheese curds sticking together after cutting the curd.

Optical isomers are two compounds which contain the same number and kinds of atoms, and bonds (i.e., the connectivity between atoms is the same), and different spatial arrangements of the atoms, but which have non-superimposable mirror images, in the same way that your left glove does not fit on your right hand. Each non-superimposable mirror image structure is called an enantiomer. The left and right enantiomers are referred to as L and D, respectively. A dairy example is lactic acid. L-lactic acid tends to remain soluble in cheese but D- or blends of D- and L-lactic acid tend to form white crystals of calcium lactate on cheese surfaces.

Principle, natural proteolitic enzyme in milk.

Can break down proteins.

Refers to micro-organisms that are able to grow at temperatures less than 7°C.

The process of breaking up and rejoining genetic material. In this case, the chymosin gene is taken out from the cow genome and placed in a plasmid, which is piece of DNA that is able to replicate independently. The plasmid is then inserted into a microorganism which starts to produce chymosin. Chymosin is produced by transcribing and translating the chymosin genetic code in the plasmid.

Another term for chymosin, the proteolytic enzyme which causes milk coagulation.

A series of dilutions that occur sequentially. Whey gets transferred into Beaker 1 filled with 99 mL of reconstituted skim milk (100x). The Beaker 1 solution gets transferred into Beaker 2 filled with 99 mL of reconstituted skim milk (10,000x). This process repeats until the solution reaches Beaker 4, which is a 1 million times dilution.

Count of the number of somatic cells in a fluid. SCC will increase with presence of pathogenic bacteria.

Syneresis is the contraction of curd to expel water, and is controlled mainly by the temperature and time of cooking, as well as the temperature of the wash water. Syneresis increases with higher temperatures during cooking or washing.