Difference between revisions of "Cooking Time and Temperature"
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==Cooking Charts and Tables== | ==Cooking Charts and Tables== | ||
+ | The tables below give a strategy for cooking and a guide for reducing the most common pathogens. To use them, select your food and source from the left column, then follow one of the guidelines. Use the color-coding to find the appropriate table to select your temperature-time combination. | ||
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=== Cooking Strategy === | === Cooking Strategy === | ||
{| class="wikitable" | {| class="wikitable" | ||
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=== Time and Temperatures for Selected Foods === | === Time and Temperatures for Selected Foods === | ||
====6.5D Salmonella Reduction Table==== | ====6.5D Salmonella Reduction Table==== | ||
+ | {| | ||
+ | |+ '''''Extended and Simplified 6.5D Salmonella Reduction Table''''' | ||
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{| class="wikitable" style="background: yellow" | {| class="wikitable" style="background: yellow" | ||
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! °Celsius !! °Fahrenheit !! Time | ! °Celsius !! °Fahrenheit !! Time | ||
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| 58.9 || 138 || 18m 17s | | 58.9 || 138 || 18m 17s | ||
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+ | |} | ||
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+ | {| class="wikitable" style="background: yellow" | ||
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+ | ! °Celsius !! °Fahrenheit !! Time | ||
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| 59 || 138.2 || 17m 28s | | 59 || 138.2 || 17m 28s | ||
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| 66.7 || 152 || 44s | | 66.7 || 152 || 44s | ||
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+ | |} | ||
+ | | valign="top" | | ||
+ | {| class="wikitable" style="background: yellow" | ||
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+ | ! °Celsius !! °Fahrenheit !! Time | ||
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| 67 || 152.6 || 39s | | 67 || 152.6 || 39s | ||
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| 85 || 185 || 0.02s | | 85 || 185 || 0.02s | ||
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==See Also== | ==See Also== | ||
*[http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/teach-others/fsis-educational-campaigns/is-it-done-yet Is it done yet?] a food safety guide from the USDA. | *[http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/teach-others/fsis-educational-campaigns/is-it-done-yet Is it done yet?] a food safety guide from the USDA. | ||
+ | *[http://www.douglasbaldwin.com/sous-vide.html#Technique Douglas Baldwin Sous-vide guide] covers safety and food pathogens. | ||
+ | *[http://www.fda.gov/Food/FoodborneIllnessContaminants/default.htm FDA information about foodborne illness] - includes a list of all the bad bugs | ||
+ | *[http://www.efsa.europa.eu/en/topics/topic/foodbornezoonoticdiseases.htm Foodborne illness information from the EFSA], the European Union's equivalent administrative body. | ||
==References== | ==References== |
Latest revision as of 04:14, 11 August 2013
As the food we cook is generally meant to be fed to humans, making sure it is safe for consumption is important. Heating food to destroy harmful bacteria is a common way to reduce risk for foodborne illness. Controlling cooking time and temperature allow a cook to maintain acceptable safety while causing minimum damage to food texture and taste.
Contents
Background[edit]
There are two types of foodborne illness: infection and food poisoning.
Infection occurs when microorganisms directly penetrate the body and grow. Sometimes these organisms can also secrete toxins. Examples include salmonella, trichinella spiralis, E. coli (certain strands), Listeria monocytogenes, and prions like BSE (mad cow). Noninvasive infection primarily involve organisms such as the tapeworm that live inside humans and, while there, secrete toxins that do damage.
Food poisoning is caused by toxins already in the food. This causes the most rapid onset of symptoms (1-6 hours) as toxins are already present and no infection needs to happen. Examples include C. botulinum, Salmonella and Staphyloccus aureus.
The possibility of symptoms from both bacteria and their toxins is why we cannot leave meat sitting in our refrigerator for too long, cook it to a "recommended temperature", and then still eat it. We could kill the active microorganisms but their toxins wouldn't go away. Foodborne illness happens on many different foods, but most people don't cook things like vegetables to make them safe. As a result, this entire guide will focus on the other problem of killing bacteria before they have already contaminated meats.
Time and Temperature[edit]
Pasteurization depends on time and temperature. As temperature increases from freezing, bacteria thrive and multiply more rapidly up to a point where they start dying. For example, each 15.2 minutes at 130 degrees Fahrenheit kills 90% of intact Salmonella bacteria. At 140 degrees Fahrenheit, this happens every 2.76 minutes. Each time this 90% killing happens is called a decade reduction. So a 2D reduction is 99%, a 99.99% reduction is 4D, and so on. If that 15.2 minute reduction is 1D, then a 5D reduction would take 15.2x5 or 76 minutes, killing off 99.999% of bacteria.
General FDA recommendations for fresh food are to reach a reduction level of 6.5D, or 99.99997% of pathogens present. When we're cooking on the stovetop or in the oven, there is no way to have this level of control over keeping the food at a particular temperature throughout much less time its holding for pathogen reduction against the guidelines. When we cook sous vide, however, we can estimate the time it takes even the center of the food to reach a temperature, and hold it at a pasteurization temperature to achieve the recommended guidelines.
Cooking Charts and Tables[edit]
The tables below give a strategy for cooking and a guide for reducing the most common pathogens. To use them, select your food and source from the left column, then follow one of the guidelines. Use the color-coding to find the appropriate table to select your temperature-time combination.
Cooking Strategy[edit]
Food | Cooking standard | Note |
---|---|---|
intact muscle (steaks or roasts) from:
|
bring exterior to desired cooking temperature, hold for time specified in 6.5D reduction table. No time and temperature standard for interior | achieves a much higher pathogen reduction level than the FDA requires for beef steak. Not appropriate for wild game or other food that may harbor parasites. Not safe for mechnaically tenderized (impaled) food |
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cook core to the temperature provided in 6.5D reduction table | core temperature is appropriate for wild game or ground or mixed meats |
|
serve raw, or cook at any time-and-temperature combination | recommendation is valid only for fish species known not to contain parasitic nematodes |
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prefreeze according to Simplified Fish freezing recommendations, then serve raw or cook at any temperature | the best temperature at which to cook fish for optimum taste and texture is generally less than that specified in food safety guidelines |
cook according to 6.5D reduction table | ||
crab, lobster, shrimp | raw (if you started with a live crustacean) | raw crustaceans carry some contamination risk from seawater; this risk can be minimized or eliminated by hot-water blanching or by cooking the core to a temperature specified in the 6.5D table. |
blanch in hot water to cook exterior according to 6.5D reduction table, then cook at any temperature | ||
core temperature provided in 6.5 reduction table | ||
poultry (whole) | core temperature provided in 6.5 reduction table | |
poultry (parts) | see [[ Simplified poultry table | |
clams, oysters, and other filter-feeding shellfish | raw (with some risk) | filter feeders can absorb pathogens from contaminated water |
core temperature according to 6.5 reduction table | ||
eggs | raw (with some risk) | pasteurized eggs are the least risky and can be served in any style |
pasteurized | ||
core temperature provided in 6.5 reduction table | ||
dairy pasteurization | for general dairy, refer to general dairy table in Modernist Cuisine | the recommendations given in the table are likely excessive but meet current standards |
for high-fat or sweet products (including ice cream), refer to the sweet/high-fat table in Modernist Cuisine |
Time and Temperatures for Selected Foods[edit]
6.5D Salmonella Reduction Table[edit]
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Poultry[edit]
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Fish[edit]
See Also[edit]
References[edit]
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