Many people from the United States, Liberia, Palau, the Federated States of Micronesia, and the Marshall Islands, who continue to use the Fahrenheit temperature scale, have trouble converting Celsius to Fahrenheit.
- Fahrenheit to Celsius: (65°F − 32) × 5/9 = 18.333°C
- Celsius to Fahrenheit: (18°C × 9/5) + 32 = 64.4°F
- Fahrenheit to Celsius, subtract 32 then divide by 1.8. (65F – 32) / 1.8 = 18
- Celsius to Fahrenheit, multiply the degree Celsius by 1.8 then add 32. (18.33 x 1.8 + 32 = 65
Still, it is quite difficult to do this mentally. A simpler but slightly less accurate method is:
To convert Celsius to Fahrenheit is to double the Celsius temperature, subtract 10 percent, and add 32. (18×2)+32
To convert Fahrenheit to Celsius is to divide the degree Fahrenheit in half, add 10% and divide by 2. (65/2)+10%/2.
If all of the above are difficult to do mentally, pick up your smart phone and ask Siri or Alexis, “What is 65 Fahrenheit in Celsius?” You can also Google it by entering “What is 65 Fahrenheit in Celsius”
Example
If the temperature in Celsius is 20˚, doubling it equals 40. Subtracting 10% (4) equals 36. Adding 32 results in 68˚ Fahrenheit.
Since we are discussing temperature, we should also discuss how temperature plays an essential role in cooking in Cuernavaca.
Cooking at 2200 meters
Those who came from a much lower elevation, say Los Angeles, which has an average elevation of 93 metres (305 feet), know that the pressure is lower at higher altitudes. This is why some have trouble climbing stairs or going for a morning run when arriving in Cuernavaca.
The lower pressure also affects cooking times. Newcomers to Cueranvaca who came from a lower elevation and attempt to prepare home-cooked meals are often surprised to find that the cooking times may vary significantly from what they are used to.
Some may have already noticed that while water boils at 212°F (100°C) at sea level, in Cuernavaca, it boils at a lower temperature, i.e., much faster, due to the lower atmospheric pressure. This is why boiling water in a covered pan will boil over the pan and spill onto the range much quicker than thought.
Lower Atmospheric Pressure
A liquid’s boiling point is the temperature at which its vapor pressure equals the surrounding atmospheric pressure. Water’s boiling point is also lower since atmospheric pressure is lower at higher altitudes. At higher altitudes, the atmospheric pressure is lower than at sea level. This means the water molecules need less energy to overcome the surrounding pressure and transition into a gaseous state (boiling). Thus, water boils at a lower temperature at higher altitudes than at sea level. However, for every 500 feet (152.4 meters) increase in altitude, the boiling point decreases by about 1°F (0.5°C).
Cuernavaca’s average elevation is about 7,200 feet (2,200 meters) above sea level, varying between a high of 7,726 feet (2,355 meters) in the northeast and 4,117 feet (1,255 meters) in the southwest.
Implications for Cooking
As stated, cooking food requiring boiling or simmering will take longer because water boils at a lower temperature at higher altitudes. For example, cooking pasta or eggs will take longer at 5,000 feet than at sea level.
Note: Most recipes are created without an idea of adjusting cooking times for different altitudes. For example, someone may have grown up in Austin, Texas (300 feet / 91.44 meters) and will give cooking times for that altitude. Thus, due diligence is necessary to discover the correct cooking time for Cuernavaca. Consider that Cuernavaca is on a mountainside, and those in the northeast will be at a higher altitude than those in the southwest.
Some smartphones have an elevation feature that allows for checking the current altitude. On the iPhone it is found by opening the Compass app. At the bottom of the screen, it displays the current coordinates and elevation.
Boiling
Cooking times for soups, stews, and pasta may need to be increased. Add a minute of cooking time for each additional 1,000 feet of elevation above sea level when boiling foods like pasta or vegetables.
Baking
Baking times must generally be decreased at higher elevations to adjust cooking times for altitude differences. Reduce baking time by 5-8 minutes per 30 minutes of bake time at sea-level for every 1,000 feet above 3,500 feet. Increase oven temperature by 15-25°F when baking to help counteract the effects of lower air pressure.
Moist Heat Cooking
Meat and poultry cooked by moist heat (like boiling, simmering, or braising) may take up to 25% more cooking time at 5,000 feet than at sea level.
Example: A roast that takes 2 hours at sea level might take 2.5 hours at 5,000 feet. The author lives in Vista Hermosa at an altitude of 1,550 meters / 5085.3 feet, which requires adding 30 minutes to sea-level roast recipes.
Frying
Decrease the frying temperature by about 3°F for each 1,000 feet increase in elevation.
Additional Tips
Increase the liquid in recipes slightly, adding 1 to 2 tablespoons at 3,000 feet and 1 1/2 teaspoons for every additional 1,000 feet. This is especially important when baking.
Flour: More flour may be needed at higher elevations.
Leavening: There may be a need to reduce the amount of leavening agents like baking powder or yeast.
Sugar: Consider reducing the amount of sugar in recipes slightly.
Experiment: It’s always a good idea to experiment with and adjust recipes based on preferences and specific ingredients.
Adjusting Cooking Time for Oven Temperature
To adjust cooking time for different oven temperatures, a good rule of thumb is to decrease the time by about 25% for every 25 degrees Fahrenheit (about 15 degrees Celsius) increase in temperature. For example, if a recipe calls for 60 minutes at 400°F and the preference is to cook it at 450°F, reduce the cooking time to about 45 minutes. Alternatively, also think of it as increasing the temperature by a certain percentage and then decreasing the cooking time by that percentage.
Calculate the percentage difference by dividing the initial temperature by the new temperature. For example, if going from 400°F to 450°F, calculate 400 / 450 = 0.889, which is 88.9%.
Adjust the cooking time: Multiply the original cooking time by the percentage difference. In the same example, if the original cooking time were 60 minutes, multiply 60 * 0.889 = 53.3 minutes.
Add a buffer: It’s always a good idea to check food early and add extra time.
General Guidelines
- Higher temperatures, shorter times. Generally, the hotter the temperature, the faster the food will cook.
- Consider the specific food: Some foods, like pastries, are more sensitive to temperature changes than others.
- Don’t be afraid to experiment: Pay attention to the oven and adjust accordingly, especially when cooking at higher temperatures.
