Tuesday, October 1, 2013

All About Cooking Oils-

"This is not exhaustive, but intended to convey only the most important information as relating to the impact of oils on health, especially cooking oils". by Su Fairchild, MD
http://www.kumc.edu/school-of-medicine/integrative-medicine/health-topics/healthy-cooking-oils.html 




Polyunsaturated fatty acids (PUFA):
PUFAs are easily oxidized by oxygen and heat, and form much higher amounts of toxic lipid peroxides than saturated or monounsaturated oils. These lipid peroxides cause oxidative damage, and their intake needs to be minimized. Some oils, such as canola and perilla, are high in alpha linolenic acid, which when heated, can lead to the formation of carcinogens and mutagens.
Omega 6 oils are found abundantly in corn, soy, canola, sunflower, safflower and other commercially used cooking oils.  The proper balance is fats in a body is important, as if our fat balance is off, cell membranes and other cellular processes do not function quite as well. People today eat way too much omega 6 oils. The ideal ratio of omega 3 to omega 6 is about 1:4.

Approximate PUFA content of various oils and fats:


Types Of Oils
PUFA
SAFA
Cholesterol
Evening Primrose oil
81%


Hemp oil
80%


Flax oil
72%


Grapeseed oil
71%


Chia oil
70%


Safflower oil
75%


Sunflower oil
65%


Perilla oil
63%


Corn oil
59%


Soybean oil
58%


Pumpkin oil
57%


Walnut oil
55-63%


Cotton seed oil
 50%


Sesame oil
41-45%


Canola oil
30-37%


Rice bran oil
36%


Beech nut oil
32%


Peanut oil
29-32%


Pecan oil
29%


Brazil nut oil
24-36%
24%

Pistachio oil
19%


Cashew oil
17%
20%

Almond oil
17%
8%

Duck fat
13%

1%
Lard
12%
41%
1%
Filbert oil
10-16%


Avocado oil
10%


Macadamia oil
10%
15%

Goose Fat
10%
1%

Palm oil
8%
50%

Olive oil
8%
14%

Butter
4%
50%

Ghee
4%
48%
2%
Cocoa Butter
3%
60%

Coconut oil
2-3%
92%
0%
Palm Kernel oil
2%
82%


Oils to Avoid:
1. Avoid food cooked in any oil over a 20% PUFA content: soy, canola, perilla, safflower, sunflower, corn, walnut oil, rice bran oil, and/or peanut oil.
2. Ideally, choose oils that have a PUFA content of 10% or less for cooking. The higher the PUFA content of an oil, the more delicate it is, and the more carefully it should be handled. This means it needs to be kept airtight and refrigerated.
3. Canola oil is about 21% linoleic acid, and 7-10% alpha linolenic acid; and alpha-linolenic acid is an omega-3 PUFA which should NEVER be heated.
4. Avoid margarine and any oil that is hydrogenated.

Oils to Cook With:
1.The best oils to cook with are the ones lowest in PUFA. But be aware that manufacturing and extraction processes can affect the quality of the oil.
2. Always choose organic virgin grade oil if possible.
3. Do not cook with any nut or seed with a high PUFA content. This is calculated by considering the percentage of PUFA in the oil, and the percentage of oil in the nut or seed.
4. Avoid cooking with walnuts, sunflower seeds, sesame seeds, pumpkin seeds, chia, flax.
5.  People do cook with sesame seeds in small amounts, but remember that almost a quarter of the volume is PUFAs.
6. Cook with virgin coconut oil, organic ghee.
7. Drizzle organic virgin olive oil over your food after it is done cooking, or if desired, sesame oil can be used for flavor.
8. Other gourmet oils not mentioned can also be used in small amounts drizzled over food, but not for cooking unless low in PUFA.
9. Coconut oil is good for stove-top cooking as well as baking. Almond oil, macadamia oil, virgin palm oil, and olive oil can be baked with but are less ideal for the stove-top.
10. Walnut oil must NEVER be heated; treat it as delicately as flax oil.
11. Many poor quality commercial ghees have measurable amounts of trans fat, which could be due to adulteration with vegetable oils. But properly made quality ghee has been shown to decrease cholesterol levels and increase excretion of bile. Ghee can also lower prostaglandin levels and decrease secretion of leukotrienes, both of which are mediators of inflammation. Wistar rats fed native and oxidized ghee showed that a 10% ghee-supplemented diet decreased arachidonic acid levels in macrophage phospholipids. This being said, some people may experience higher triglyceride levels with ghee, so if you consume ghee, do so in moderation. It is important that ghee be organic, as non-organic butter and therefore non-organic ghee is high in PCBs(Polychlorinated Biphenyl). PCBs belong to a broad family of man-made organic chemicals known as chlorinated hydrocarbons).
Health benefits and how to make ghee from butter. http://nutritionforasianindians.blogspot.com/2013/10/how-to-make-ghee-from-butter-and-its.html

Benefits of Healthy Oils:
1. Studies have shown that moderate (not high) fat diets can promote weight loss.
2. Coconut oil has the added benefit of being high in medium chain fats that the body preferentially burns for energy instead of storing as fat.
3. One to four teaspoons of good oil with each meal is very reasonable. Olive oil is high in monounsaturated fats, which are beneficial in small to moderate amounts.
4. Avoid taking in any extra processed or heat damaged polyunsaturated fat as much as possible.
5. Good fats and oils are very important, as they are required for absorption of fat soluble vitamins.
6. The cells in our body also require good fats in the cell membrane. We cannot live without fat.
7. As you can see in the chart below, coconut oil contains the most saturated fat of all edible oils. Don't be scared away by the negative view of 'saturated fat' portrayed by the media. Many studies have shown that a low-fat diet is not the answer for preventing heart disease, and some scientists are calling for new dietary guidelines that reflect this discovery".
Type of Oil Monunsaturated Polyunsaturated Saturated
Canola 58.9 29.6 7.1
Coconut 5.8 1.8 86.5
Corn 24.2 58.7 12.7
Flaxseed 22 74 4
Grapeseed 16.1 69.9 8.1
Olive 77 8.4 13.5
Palm 37 9.3 49.3
Palm Kernel 11.4 1.6 81.5
Peanut 46.2 32 16.9
Safflower 12.6 73.4 9.6
Sesame 39.7 41.7 14.2
Soybean 23.3 57.9 14.4
Source: http://www.virgintogo.co.uk/

Read More : http://foodmatters.tv/articles-1/what-oil-is-best-to-cook-with-and-which-oils-should-never-be-heated


Article :Healthy Cooking Oils by Su Fairchild, MD
Copyright 02/21/2012, revised 02/27/2012
This page may be freely linked to or reproduced only in its entirety with proper acknowledgements.
Acknowledgement and thanks to Diana Noland RD, who shared knowledge with me.
References:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3215354/ "The effect of ghee (clarified butter) on serum lipid levels and microsomal lipid peroxidation"