Week 16: Cooking Oil
3 quarts of Cooking Oil
After this week, you should have 3 quarts stored. The program goal is 8 qts. We will address Cooking Oil 1 more time (in week 24).
There are so many oils on the market to choose from and for the longest time, I had no idea which ones were healthy, which ones weren’t, which ones were best for cooking, which ones should avoid heat (or really that any of them were susceptible to heat breakdown), etc. The following information might be more than many of you care about, and if you already know what kind of oil you need, then don’t even worry about reading the rest and go on storing what you use and use what you store. However, if you’re not sure what kind you want/need or would like to learn a little more, then read on.
Types of Fats: Saturated, Unsaturated (Mono and Poly), and Trans
Saturated fats have no double bonds in their chemical structure, and thus, they are “saturated” with as many hydrogen atoms as possible. Because of this chemical structure, they are typically solid at room temperature and are very stable. They also resist oxidation, so they often can tolerate high temperatures. They are found primarily in meat and dairy, but also in palm and coconut oil. Saturated fats can adversely affect certain aspects of your lipid profile and increase the risk for cardiovascular disease.
Unsaturated fats: (Mono and Poly):
Unsaturated fats, on the other hand, have the opposite positive affect, are often preferred. Monounsaturated and Polyunsaturated fats fall under the “Unsaturated” category, and have at least one double bond. Because of this double bond, they are not saturated with as many hydrogen atoms as possible. Hence the designation “Un” (i.e. not) saturated. Because of this unsaturated chemical structure, unsaturated fats are typically liquid at room temperature.
Monounsaturated fats have only one (hence Mono) double bond in their molecular structure. They may help in maintaining the overall health of cells. Further, they can lower bad cholesterol, which reduces the risk for heart disease and stroke in the long run. Monounsaturated fats are liquid at room temperature and are generally more stable than polyunsaturated fats. Monounsaturated fats are found in canola, nut and olive oils. The American Heart Association (AHA) recommends relying more on monounsaturated than polyunsaturated fats.
Polyunsaturated fats have two or more (hence Poly) double bonds in their structure. Much like monounsaturated fats, polyunsaturated fats can help lower bad cholesterol. Polyunsaturated fats also contain omega-3 and omega-6 fatty acids, which your body needs for brain function and cell growth. Polyunsaturated fats are also liquid at room temperature, are the least stable of the three fats, and are typically not labeled for high heat or "high oleic." They oxidize easily and are found in seafood, corn, safflower, soybean and sunflower oils.
A quick word on trans-fats. Trans-fats typically do not exist naturally and therefore are considered “unhealthy.” Trans-fats are artificially formed through a chemical process called hydrogenation, which bombards an unsaturated fatty acid with extra hydrogen molecules in an attempt to saturate it. The result is the formation of hydrogens on opposite sides of a double bond in their chemical structure, which is not at all desirable. Nonetheless, manufacturers started doing this for several reasons, such as: It is an inexpensive process that extends the shelf-life of food, it helps the fats become more solid at room temperature and it actually helps make certain foods more palatable (fastfoods???). These trans-fats are unequivocally bad for you. But don’t worry too much about these artificial trans-fats. In 2013, the FDA declared artificial trans-fats as “generally not recognized as safe” due to studies linking high trans fat consumption to cardiovascular disease. After further investigation on the effect of artificial trans-fats in foods, the FDA ruled in June 2015 that food manufacturers needed to find alternative measures in preparing their processed foods that would eliminate the use of trans-fats during the preparation process and further mandated that this be done by 2018. So trans-fats, for the most part, have been removed from foods and are banned in many countries.
The Extraction Process: Chemical Extraction vs. Pressed (Expeller and Cold)
Getting oil from the seed requires a process. You can squeeze or mechanically “press” it out or you can add chemical solvents that will help release these oils. Olive, avocado and walnut oil, for example, are from soft fruits or nuts that need only expeller pressing and centrifuging, and therefore may be labeled “cold-pressed.” Harder seeds, such as soy or canola, usually require some pre-treatment such as steam before pressing, but they still do not rely on chemical solvents. In contrast to these two methods are the mass-market oils that are generally extracted with toxic solvents such as hexane. These oils then must undergo harsh treatment to remove the solvent. More chemicals, very high heat, and straining are used to deodorize and bleach the oils, rendering them inferior in taste, fragrance, appearance and especially nutritional quality.
Before the oil is taken out of the oilseed, the seeds are ground up into a paste. These ground up seeds are then washed with a chemical solvent, usually hexane (a petroleum distillate), to release the fat in the seed. Once the oil has been removed, the solvent needs to be removed from the oil. So, it is then “flashed off” by heating the oil in a sealed chamber. The oil/solvent blend is heated to roughly 212˚ F, so that the solvent can be separated out. In theory, this method shouldn’t leave any residue of solvent behind, but in actuality, it does leave a small part behind. Finally, the oil is bleached and deodorized in order to remove any smell of solvent that may remain in the oil. The oil extraction efficiency is about 97-99% with this method and hence, oils made using this method are the cheapest.
The downsides are it uses a petroleum based chemical (chemicals are always bad) to extract the oil, and there are huge amounts of heat involved, which oxidizes the oil, and compromises its nutritional value. Heating it to such high temperatures alters the properties of the oil molecules in unfavorable ways.
In this method, no chemicals are used and no heat is added, but heat can be generated simply as result of the process. A large press is used to physically squeeze the oil from the seed. An expeller press is a screw type machine, which presses oil through a caged barrel-like cavity using continuous pressure to literally squeeze the oil from the seeds. As mentioned above, there isn’t any added heat in this process, but the pressure and friction involved in the pressing process creates heat from the unit in the range of 140-210˚ F. So technically, this process is not “cold pressed”. Expeller pressing gets out about 87-95% oil, and thus it is a bit more expensive than the cheapest, solvent extracted oil.
Again, due to the heat that is formed in the expeller, there is bound to be some oxidation of oil and also an alteration in the properties of the oil’s molecules. Further, after expelling the oil, many manufacturers add preservatives to the oil to increase their shelf life.
The third and final process of oil extraction is the Cold Pressed Process. According to standards, cold pressed oils are to be expelled at temperatures below 122˚ F, usually done at 81˚ F. Cold pressed oils extraction efficiency is usually about 60-70% only, making them the most expensive of the lot. And since cold pressed oils are not subject to high heat or chemicals, they are the safest of them all.
So the next time you buy oil, look for “Cold Pressed” oils. The ones that are not labeled “Cold Pressed” may be expeller processed or solvent extracted.
Unrefined vs. Refined Oils:
These oils are filtered only lightly to remove large particles. Some, such as sesame or olive oil, may appear cloudy or have visible sediment after sitting. This does not compromise the quality of the oil, however, these leftover particulates lower the oil’s “smoke point” and will therefore burn easily and develop unpleasant flavors and unhealthy properties. Unrefined oils are best used unheated in dressings or on low heat settings, such as while sautéing or baking. Unrefined oils are “whole” oils and their flavor, color and fragrance are more pronounced than refined oils. Like unrefined whole grain flours, unrefined oils are more nutritious, but have a shorter storage life than their refined counterpart. If you choose to bake with unrefined oils, expect the flavor to be more pronounced.
These oils are more thoroughly filtered and strained than unrefined oils, usually with some additional heat, but without harsh or damaging chemicals. While refining does reduce the nutrient level and flavor of the oil, it also removes particles and resins which lowers the “smoke point” or burning point of the oil, making these oils a good choice for high-heat cooking and frying. They also tend to store a little longer. The refined oils recommended for high heat cooking and deep-frying are “high oleic” forms of safflower and sunflower oils. These are from plants bred to be high in monounsaturated fats, as opposed to polyunsaturated fats which oxidize easily and aren’t suited for high heat. To check if it’s “high oleic,” read the nutrition panel on the bottle.
All oils, especially unrefined oils, should be refrigerated after opening to prevent oxidation and rancidity. Natural oils should smell and taste fresh and pleasant. Can’t tell? If in doubt, throw it out. Studies indicate that rancid fats may promote cancer and heart disease. Oil that’s firmed up in the refrigerator will liquefy at room temperature in a few minutes. Place the bottle in a container of warm (not hot) water for five minutes. The quality will not be harmed.
So you have to make sure you rotate your oils, and not store them longer than the expiration date. In a nutshell, don’t sit on your oil supply for years without rotating it. Just a little bit rancid is just a little bit poisonous.
Because of this difficulty in storing fats and oils for any long period of time, many books and articles on the subject of food storage make only passing mention of them, if they say anything at all. This is unfortunate because fat contains nine calories per gram compared to the four calories contained by either carbohydrates or protein. This makes fat a valuable source of concentrated calories that could be of real importance if faced with a diet consisting largely of unrefined grains and legumes. For small children, infants and the elderly, they may not be able to consume the volume of food that would be necessary in the course of a day to get all of the calories they would need to avoid weight loss and possible malnutrition. Additionally, fats play an important role in our perception of taste and texture, and their absence would make many foods more difficult to prepare and consume. Furthermore, a small amount of dietary fat is necessary for our bodies to properly absorb fat soluble vitamins like A, D, E and K.
Long-term storage of fats may be problematical, but it is not impossible. There are some general rules you can follow to get the most life out of your stored cooking oils and fats:
First, exposure to oxygen, light and heat are the greatest factors to rancidity.
If you can, refrigerate your stored oil, particularly after it’s been opened.
If possible, buy your oils in opaque, airtight containers. If you purchase it in plastic, particularly clear plastic, then transfer it to a gas-impermeable glass or metal container that can be sealed airtight.
If you have the means of doing so, vacuum sealing the storage container is an excellent idea as it removes most of the air remaining inside, taking much of the oxygen with it.
Transparent glass and plastic containers should be stored in the dark, such as in a box.
Regardless of the storage container, it should be stored at as cool a temperature as possible and rotated as fast as practical.
Oils and fats with preservatives added by the manufacturer will have a greater shelf life than those without them, provided they are fresh when purchased.
Unless they have been specially treated, unopened cooking oils have a shelf life of about a year, depending upon the above conditions. Some specialty oils, such as sesame and flax seed, have even shorter usable lives. If you don’t use a great deal of it, try not to buy your fats in large containers. This way you won’t be exposing a large quantity to the air after you’ve opened it. Once opened, it is an excellent idea to refrigerate cooking fats. If it turns cloudy or solid, the fat is still perfectly usable and will return to its normal liquid clear state after it has warmed to room temperature. Left at room temperatures, opened bottles of cooking oils can begin to rancid in anywhere from a week to a couple of months, though it may take several more months to reach such a point of rancidity that it can be smelled.
Although darker colored oils have more flavor than paler colored oils, the agents that contribute to that flavor and color also contribute to faster rancidity. For maximum shelf life, buy paler colored oils.
Cooking with Oils
When oil gets too hot, it begins to smoke, and this is termed its "smoke point." You should never heat oil to its smoke point. If oil smokes in the pan, discard it. The temperature is too high. Clean the pan and start over at a lower temperature. The point where oil smokes signals that the oil has been damaged and potentially cancer-causing properties have formed. For more information on which oils to use with heat, reference the chart below. Please note that this chart does not view correctly on mobile devices.
Note: One common question is, Can I use olive oil for all of my cooking? The answer is No. Extra virgin olive oil deserves its reputation as a healthy culinary oil. It contains heart-healthy monounsaturated fats and phenols — protective compounds that provide numerous benefits. But to maximize the health benefits, it is recommended you use it raw for salads and dips or for lower-heat cooking.
This guide will help you choose what oils are best suited for specific cooking techniques, or used raw.
In conclusion, I hope you find the following excerpt from Mark Sisson’s “The Primal Blueprint” Chapter 4, subsection “Fats and Oils” helpful and educational. I know I did.
Many oils offer significant health benefits, but they are generally high in calories with minimal vitamin and mineral values. Many oils offer a way to boost your intake of omega-3s and other healthy monounsaturated and saturated fats, but moderation is advised in this food category. Nuts and avocados offer similar health benefits to oils and carry much greater nutritional value. It’s important to choose your oils wisely and strive to balance omega-6 and omega-3 intake. Stay with nut oils as they offer a healthy alternative to the decidedly less healthy polyunsaturated oils from vegetables, grains, and other sources.
As you probably know, various processing methods dramatically affect the health quality of olive oil, with extra virgin designated as the purest form. As with fruit, you should strive for oil produced locally or at least domestically (instead of the vast majority of products shipped from Greece or Italy) for maximum freshness. The additional distinction “first cold press only” suggests that the olives have been pressed only once and bottled immediately, instead of being repeatedly pressed for maximum crop yield (this is the most common method, particularly with the large bottle–low price imports). You’ll notice the difference with a single taste of a locally grown, first cold-pressed extra virgin olive oil in comparison with a much blander, duller-tasting extra virgin import. The aroma and taste are incredibly powerful—the high level of tocopherols (a potent antioxidant) may actually sting the back of your throat!
High omega-3 oils are a great dietary addition. These oils are extremely delicate and easily suffer damage from exposure to heat, light, and oxygen. Thus, you’ll find them in health food stores refrigerated in small black containers (recognize that all bottled oils are damaged by heat, light, oxygen, and time). It’s best to store your oils in the refrigerator and use them quickly—usually within six weeks of opening. Every time oils are exposed to air, they oxidize a bit. If you detect a slightly rancid smell in any oil or if it’s been on the shelf for more than six months, discard the product immediately.
High polyunsaturated oils (corn, safflower, sunflower, cottonseed, and all partially hydrogenated oils) should be avoided, because they also oxidize easily. Canola oil, while enjoying mainstream popularity due to its high monounsaturated content, is inferior to olive oil because it’s a heavily refined, genetically engineered product only recently cultivated (in contrast to olive oil’s reign of thousands of years). Canola oil is derived from the rapeseed plant, which is thought to be toxic to humans and animals (particularly harmful to respiratory function). Most canola oil is put through a deodorizing process that converts some of its natural omega-3s into harmful trans fats.
Coconut oil offers numerous health benefits but has received a bad rap because it’s the most saturated of all oils (at 92 percent, it’s nearly solid at room temperature; this is the distinction between a saturated and an unsaturated fat). As you may be aware, saturated fat does offer many health benefits. Coconut oil has been found to help normalize blood lipids and protect against damage to the liver by alcohol and other toxins, and it has anti-inflammatory and immune-supporting properties. Coconut oil is less sensitive to heat than unsaturated oils, making it the best choice for cooking. Butter and unprocessed palm oil are also great choices for cooking.
Great Fats and Oils: (in alphabetical order)
This list contains a variety of saturated and unsaturated types. The saturated fats listed here (animal fats, butter, coconut oil, and palm oil) are great choices for cooking because they are temperature stable (they won’t oxidize under high heat). Review the list carefully, stockpile your fridge, and be sure to stick to the best-intended use for each.
Animal Fats: Chicken, duck, or goose fat; lard (aka pork fat), beef, or lamb tallow; and other animal fats are excellent for cooking because their saturated composition makes them temperature stable.
Butter: An excellent choice for cooking or enhancing taste of steamed vegetables. A good source of vitamins A and E as well as selenium.
Coconut Oil: Temperature stability and numerous health and immune-supporting benefits make it the premier choice for cooking.
Dark Roasted Sesame Oil: This oil’s intense flavor makes it a great choice for wok vegetables, meat, or salads.
High Omega-3 Oils: These delicate oils come in small dark containers and require refrigeration and quick use. They are a great addition to salads or protein shakes for an omega-3 boost. Recent research suggests that it may be more difficult to assimilate omega-3 benefits from flaxseed oil than other types. Choose borage, cod-liver, krill, salmon, hemp seed, or hi-oleic sunflower or safflower seed oils (not to be confused with their unhealthy polyunsaturated derivatives) as alternatives.
Marine Oils: Typically delivered in capsule or soft-gel supplement form, these fish or krill oils are an excellent source of omega-3s.
Olive Oil: Choose extra virgin, first cold press, locally grown, and savor the flavor! Best not to cook with olive oil due to temperature fragility.
Palm Oil: The unprocessed variety (not to be confused with widely used partially hydrogenated palm oil) is great for cooking.
Oils and Fats to Strictly Avoid: (in alphabetical order)
Many of these oils are considered polyunsaturated fatty acids (PUFAs), which have a variety of serious health objections. The concerns stem from PUFAs’ long-chain fatty acids, which are unstable, quickly go rancid, and are easily oxidized in your body. Consequently, PUFAs have a pro-inflammatory effect and disturb homeostasis in many other ways. The endocrine system is especially vulnerable to the effects of PUFA ingestion, leading to symptoms like a slowed metabolism, low energy levels, and sluggish thyroid function. Heavy consumption of PUFAs in the modern diet is blamed as a leading contributor to obesity, diabetes, heart disease, cancer, immune problems, arthritis, and other inflammatory conditions. Strictly avoid PUFAs, trans and partially hydrogenated fats, and the other fats and oils detailed as follows:
Canola Oil (PUFA): Heavily refined and genetically engineered. Still can contain small amounts of trans-fat.
Cottonseed Oil (PUFA): Heavily processed oil popular in packaged and frozen foods, often in partially hydrogenated form.
Corn Oil (PUFA): Derived from a grain! High omega-6, low omega-3 value.
High-Temperature Processing: Avoid all oils heated to high temperatures in the course of frying or deep frying food.
Margarine: Contains objectionable ingredients and processed with chemical additives at high temperatures. While most margarines today have the “trans-fat free” distinction proudly adorning the label, the PUFAs that some margarines contain still potentially raise LDL, lower HDL, and suppress immune function and insulin sensitivity. Research strongly suggests an increased risk of cancer and heart disease from margarine use.
Partially Hydrogenated Oils: High-temperature, chemically altering processing methods make these toxic to your DNA. Extreme health hazard!
Safflower and Sunflower Oils (PUFAs): Some of the most popular PUFAs.
Soybean Oil (PUFA): High omega-6, low omega-3 values. There is evidence that some forms may disturb thyroid function.
Trans Fats: Similar, but not identical, to partially hydrogenated oils. Also an extreme health hazard!
Vegetable Shortening: Similar to lard in appearance but chemically produced to create a trans fat. The brand name Crisco is an acronym for “crystallized cottonseed oil.” Bad stuff—stay away!”