what is the maximum amount of time high risk food can be in the temperature danger zone
Danger zone (food safety) The temperature range in which food-borne bacteria can grow is known as the danger zone. Food safety agencies, such as the United States' Food Safety and Inspection Service (FSIS), define the danger zone as roughly 5 to 60 °C (41 to 140 °F).[1][2][3] The FSIS stipulates that potentially hazardous food should not be stored at temperatures in this range in order to prevent foodborne illness (for example, a refrigerator's temperature must be kept below 4 °C (40 °F)[4]), and that food that remains in this zone for more than two hours should not be consumed.[5] Foodborne microorganisms grow much faster in the middle of the zone, at temperatures between 21 and 47 °C (70 and 117 °F).[6]
Medieval cuisine Food preservation methods were basically the same as had been used since antiquity, and did not change much until the invention of canning in the early 19th century. The most common and simplest method was to expose foodstuffs to heat or wind to remove moisture, thereby prolonging the durability if not the flavor of almost any type of food from cereals to meats; the drying of food worked by drastically reducing the activity of various water-dependent microorganisms that cause decay. In warm climates this was mostly achieved by leaving food out in the sun, and in the cooler northern climates by exposure to strong winds (especially common for the preparation of stockfish), or in warm ovens, cellars, attics, and at times even in living quarters. Subjecting food to a number of chemical processes such as smoking, salting, brining, conserving or fermenting also made it keep longer. Most of these methods had the advantage of shorter preparation times and of introducing new flavors. Smoking or salting meat of livestock butchered in autumn was a common household strategy to avoid having to feed more animals than necessary during the lean winter months. Butter tended to be heavily salted (5â€“10%) in order not to spoil. Vegetables, eggs or fish were also often pickled in tightly packed jars, containing brine and acidic liquids (lemon juice, verjuice or vinegar). Another method was to seal the food by cooking it in sugar or honey or fat, in which it was then stored. Microbial modification was also encouraged, however, by a number of methods; grains, fruit and grapes were turned into alcoholic drinks thus killing any pathogens, and milk was fermented and curdled into a multitude of cheeses or buttermilk.[47]