Minutes of the Institute for Oleic Research, Part 4

09.26.08
Which oil is fit for frying and which falls flat? The Institute investigates a wide range of specialty oils.

At the Institute, we have been noticing a profusion of new bottles of culinary oils in our local supermarkets. From four corners of the world, these products often have lively, colorful labels, but they tend to be deficient when it comes to providing information about the oils’ properties and uses. In the coming weeks, we’ll be collecting samples of oils now available at the market and analyzing them so we can report their advantages and disadvantages. Should they be used for cooking? And, if not, do they find their highest and best use in salad dressings or as flavoring agents?

Avocado Oil

A quick search of oleic literature indicates that avocado oil is a popular base for anti-wrinkle creams, and one source asserts it has sunscreen properties. But can avocado oil also be used to make french fries? The sample we bought originated in Chile, was cold-pressed from Hass avocados, and—according to the label—its virtues can be credited to “the rich and generous Chilean land.” It retails for $19.99 (500 ml), making it about 4 cents per milliliter (or $1.18 per ounce). It comes in a nearly opaque glass bottle, which suggests that oxidation during storage might be a problem. (Our storage tests have not yet been completed.)

The smoke point of avocado oil is the highest we’ve found for a vegetable oil, at 520°F (271°C). That makes it a superlative medium for frying, if not for the high price; frying with it would be like putting Barolo in sangria.

The oil appeared dark green with black highlights when poured into a clear glass Petri dish set down on a white lab towel. When we tasted it, the flavor was mild and rich, with a fruity finish and a slight peppery burn at the very end, like the kind you get from Italian olive oils that have been recently pressed.

Our conclusion: Use it wisely, and primarily as a flavoring. We tested it by frying potatoes in it (great results, but way too expensive), in a vinaigrette (good usage, but it barely tastes different from olive oil, so go easy on the vinegar to highlight the oil’s taste), and as a flavoring agent (especially decadent when poured over an avocado half sprinkled with sea salt). The oil also excelled in a gazpacho, which we thickened in the old fashioned way with breadcrumbs.

Grape Seed Oil

Our Huile de Pepins de Raisin, which came in a metal cylinder, was produced by a French company that claims to have been making it since 1898. It comes from the pressed seeds of purplish grapes (species Vitis vinifera). Despite the grapes’ color, the oil is nearly colorless. It has no distinct flavor either, except for a very mild burn on the tongue, not apparent to everyone at the Institute who tasted it.

At $10.99 for a one-liter can, the price is relatively cheap: 1.1 cents per ml (or 32.8 cents per ounce). The oil has a smoke point of 420°F (216°C), so it worked magnificently for frying. Potato cubes turned out crisp and golden. The oil didn’t work well in a salad dressing though, adding no perceptible flavor or particular richness. Since it has virtually no flavor, it wouldn’t be worthwhile as a flavoring agent either.

Our conclusion: Fry away! This oil works almost as well as peanut oil for frying and is competitive in price.

Sunflower Oil

The sunflower oil we collected had the rather evocative name of Rapunzel, and its label boasted that it had been milled in the south of France from organic sunflower seeds. Organic or not, the oil has a pleasing pale orange color and an almost-nutty flavor.

While its smoke point is low (320°F/ 160°C), meaning it isn’t particularly good for frying or sauteeing, this oil’s taste made it a natural choice for dressings, especially a light one that doesn’t overwhelm, say, baby lettuces. Since its delicate flavor is unassertive, use less vinegar, or a sweet light vinegar like white wine or apple, for dressings.

The 500 ml bottle retailed for $8.99, so the cost per ml is 1.8 cents (or 53 cents per ounce). This monosaturated oil is reportedly high in Vitamin E and Omega 9 fatty acids, so maybe the higher price is justified by perceived health properties.

Our conclusion: We consider it a good, light addition to any household portfolio of culinary oils.

Subscribe to Gourmet