Oils 101: The best oils for cooking — and which to avoid

Sesame Oil

With the sesame plant being drought-tolerant,able to grow where other crops failed, sesame oil is of the oldest oils in existence.

It has been used by the Chinese since 5000 years ago and was once thought to have mystical powers as shown in the expression “open sesame,” from the Arabian Nights tale of “Ali Baba & the 40 Thieves.”

If you want an all-purpose cooking oil, opt for non-toasted sesame oil since it has a naturally neutral flavor. To add a rich nutty flavor to dishes like stir-fries or if you’re crafting a strong sesame flavored dressing, use the toasted variety.

Safflower Oil

Safflower oil is one of the least flavorful cooking oils and is prized for being neutral as it doesn't mask or distract from the flavors of other ingredients.

Saflower oil has 2 neutral-flavored oil:

a. regular-has a high polyunsaturated fat content that helps it remain liquid at cold temps and is ideal for dressings

B. high-oleic varieties- better for high-temp cooking, like deep frying and roasting.

Safflower oil is also used commercially to make margarine with California as its main source.

Vegetable oil

The top four vegetable oils consumed in the US are soybean, canola, palm, and corn oil. Also referred to as RBD oils which describes the process by which they are manufactured: refined, bleached and deodorized.

Vegetable oil can also be made from any different oils, including corn, ___ and more.

It’s a staple in baking because of its neutral flavor and goes well in cooked dishes where you don’t want to mask the flavor of the ingredients.

Canola Oil

Canola oil is made from pressed rapeseed and can handle high heat, so it’s usually a go-to for deep frying. Plus, it has a mild flavor that gives it a wide range of use. Use it for sautéing, baking and frying, but skip it for dressings and sauces since it doesn’t add much flavor.

Sesame seeds contain about 44-60% oil, which can be extracted 2 ways 

A. By expeller-pressing 

Cold-pressed oil

- oil extracted by expeller-pressing the seeds in cooler temperatures

- produces the highest quality oil

B. By the use of chemical solvents. 

- when sesame seeds are further refined through solvent extraction (usually hexane), neutralization and bleaching to improve its cosmetic aspects especially when it was sourced from low quality seeds. 

Sesame oil derived from quality seeds are usually not refined to preserve its nutty, sesame flavor. 

The top four vegetable oils consumed in the United States are soybean, canola, palm, and corn oil.

These are referred to as RBD or refined, bleached, deodorized oils – referring to the process by which they are manufactured.

RBD oils are produced by crushing the plant material, usually seeds, to express the oil, followed by extraction of the crushed material with a low-boiling solvent, most commonly hexane, to obtain the remainder of the oil.

One primary concern is the use of solvents such as hexane to extract the maximum amount of oil from the seed.

Refined oils extracted with hexane contain approximately 0.8 milligrams of residual hexane per kilogram of oil.

Hexane is a very volatile solvent with a very low toxicity used to extract oils from plant material since the 1930s. 

While there is no clear evidence of the dangers of ingesting foods containing trace residual concentrations of hexane yet, hexane has been recognized for more than 40 years to cause long-lasting and even permanent nerve damage in the limbs.

https://www.msdsonline.com/2014/11/19/understanding-the-hazards-of-hexane/

Hexane is a chemical commonly extracted from petroleum and crude oil consequently giving off a subtle, gasoline-like odor.

Common uses of hexane include:

• Extracting edible oils from seeds and vegetables
• As an additive in gasoline, glue, varnishes and inks
• As a cleaning agent in the textile, furniture and printing industries;
• As a special glue used in roofing, shoemaking and leather products.

Though trace levels of hexane in RBD oils is relatively harmless, studies show that hexane, if (short-term exposures) inhaled or absorbed by the skin, can cause headaches, dizziness, nausea, drowsiness, and other effects similar to intoxication.

If exposures are high, long term and frequent, the effects can be long-lasting or permanent. High exposure levels have been associated with a condition called peripheral neuropathy.

If swallowed, it may cause severe abdominal pain and affect the respiratory system, resulting in shortness of breath, coughing, burning of the mouth, throat or chest.

Those who would like to avoid RBD oils can opt for cold-pressed oils instead, since they are not treated with heat, not extracted with solvents, and not deodorized. 

Depending on the type, these oils may be labeled as “cold-pressed,” “unrefined,” “virgin,” etc. 

However, due in part to their higher price point there were cases of adulteration (such as undisclosed “blending” with an RBD oil) of these types of oils. 

To completely avoid RBD oils choose only high-quality oils from reputable sources that have been verified to meet quality standards

Sunflower Oil

Contrary to what is believed, the higher smoke point of sunflower oil is not an indicator that it a great choice for roasting and frying.

There are types of sunflower oils that when heated to temperatures of 356°F (or 180°C as in deep-frying) release aldehydes.

*aldehydes - toxic compounds that can damage DNA and cells, consequently contributing to conditions like heart disease and Alzheimer’s.

Therefore, gentle, low heat cooking methods such as stir-frying may be a safer use of sunflower oil.

It can go rancid very quickly, so be sure to store it in a cool, dry place.

Though often touted as a healthy oil that may benefit heart health, potential benefits of sunflower oil depend on the type and nutrient composition.

Sunflower oil is primarily composed of:

A. linoleic acid - a polyunsaturated fat

B. oleic acid - a monounsaturated fat

There are 4 types of sunflower oil available in the market:

1. High linoleic (68% linoleic acid)

2. Mid-oleic (65% oleic acid)

3. High oleic (82% oleic acid), and

4. High stearic+high oleic (72% oleic acid, 18% stearic acid)

- 80% oleic, 20% lanoleic avid + saturated fats

- the healthiest of the 4; has the most amount of monounsaturated fat.

*Has 1 of the highest oleic acid content of all vegetable/seed oils

- a favorite among home cooks, food manufacturers:

• a stable oil that can withstand high heat, making it ideal for frying and baking
• has a more neutral taste, lets the true flavor of the ingredients to shine through
• its high oleic acid content helps the food last longer in storage without going bad, helping manufacturers improve the shelf life of food, reducing the amount of money that goes to wasted products.

-70% lanoleic acid + 20% oleic+10 % other saturated fats

- the original sunflower oil,has been the most common type of sunflower oil in the market

- not as stable as the other 2: hydrogenated to become more stable

- least healthy of the 4

- too much of it can be harmful: can worsen cholesterol levels & heart health

- major ingredient in margarine, salad dressings & shortening

- found to be more potent than HOSO when applied topically in treatment of skin problems, improves skin's natural barrier, has an anti-inflammatory effect that is safe enough to be used topically on premature infants

- 65% oleic acid + 25% linoleic acid + <>10% saturated fats; trikes a balance between the oleic and linoleic acid content

- a healthy option that gives you both the essential fatty acids in your diet. 

- considered to be the standard sunflower oil, the most common type available in the world, giving health benefits at a reasonable price point, similar to that of other seed oils.

- used by manufacturers of snacks like potato chips and crisps, as it is affordable and yet will not go rancid in storage without hydrogenation.