Summer Sausage

Summer sausage represents a group of fermented meat products where commonly a lactic acid bacteria culture is added. The product can be made from dark poultry meat, skin and fat, but usually some pork meat and fat are included; pork fat is added because it is more stable and harder at room temperature. In this process, lactic acid bacteria are used to lower the pH of the product from about 5.7 - 4.8 and also to add unique flavor notes. In the past, microorganisms from a previous successful batch were introduced into a new batch, and the product was allowed to ferment. Today, the industry mainly uses commercial starter cultures with a known composition of microorganisms (predominantly lactic acid bacteria). The producer can select from cultures that grow at different temperatures and produce distinct flavor compounds. Recently, a lot of progress has been made in the field of starter cultures, mainly through the use of genetic engineering, where desirable characteristics from one strain can be moved to another.

Overall, the use of a starter culture is highly recommended because it ensures that lactic acid bacteria dominates the fermentation (commonly added at about 107 per g), suppresses pathogens and produces the desired flavors. The degree of fermentation can be controlled by the quantity of the carbohydrate added (i.e., an energy source for the microorganisms) or by continuous pH monitoring. After the fermentation (1-2 days with a starter culture), the product is either smoked, cooked or only dried. The dry product is usually shelf stable due to its low pH (4.6 - 5.0) and low water activity (Aw - 0.90).