Swiss cheese

Swiss cheese is the generic name, in the, and , for several related varieties of cheese, all of which resemble the Swiss Emmental. It has a distinctive appearance, as a block of the cheese is riddled with holes known as "eyes."

The use of Swiss cheese as a generic name for a type of cheese (as opposed to a descriptor of national origin) is not common in the, where the cheeses are usually distinguished individually. As well, that type of cheese is called fromage suisse (Swiss cheese) in Canadian French usage, but not in European French-speaking countries.

Three types of bacteria are used in the production of Emmentaler cheese: Streptococcus thermophilus, Lactobacillus, and Propionibacterium shermanii. In a late stage of cheese production, P. shermani consumes the lactic acid excreted by the other bacteria, and releases carbon dioxide gas, which slowly forms the bubbles that make up the eyes. Swiss cheese without eyes is known as "blind."

In general, the larger the eyes in a Swiss cheese, the more pronounced its flavor; This is because the same conditions that lead to large eyes - longer aging or higher temperatures - also give the acting bacteria and enzymes more time to produce flavor. This poses a problem for makers of pre-sliced Swiss cheese, the most popular category in the United States. Cheese with large eyes doesn't slice well, sometimes coming apart in mechanical slicers. This costs time and money and is one reason why US manufacturers usually produce a product less aged and flavorful than imported cheeses of the same style.

Baby Swiss is another related cheese often found in the US. Made by substituting water for the milk's whey to slow bacterial action, baby Swiss cheese has smaller holes and a milder flavor. Baby Swiss is often made from whole milk.

Lacy Swiss is a further variety of US small hole swiss cheese made with low fat milk. Lorraine swiss is an example of this style.

"Swiss cheese" is often used as a term for when an item has metaphorical holes in it, such as a faulty memory or a poor alibi.