The zero trans fat cooking oil contest


When you buy par-fried French fries, the fries contain the oil that was used for the par-frying. You need to purchase French fries or other food items that have been par-fried in non-partially hydrogenated oil.

If you use French fries or another food item that have already been par-fried in partially hydrogenated oil before they reach the restaurant, the partially hydrogenated par-fry oil will mix with the oil that you have poured in the fryer and get into the food. As you continue to fry without changing the oil, as much as 50% or 60% of the oil in the fryer may be the par-fry oil! As a result, you may violate a trans fat labeling or ban regulation.

We asked a leading expert, Helene Clark, to advise you how to select the best zero trans fat par-fried French fries.

Selecting Zero Trans French Fries
by Helene Clark, Director of Marketing -
Health & Wellness, ConAgra Foods
Lamb Weston

Providing zero grams trans fat french fry options requires making choices about their preparation and the oil in which they’re fried.

The good news is that the industry has been working on trans fat solutions for several years, and a lot of zero grams trans fat options are available in the marketplace already with many more on the way. If the specific fry you currently use isn’t already providing zero grams trans fat per serving, check with your manufacturer to find out when it plans to convert that item. You may have to choose between waiting until that specific item is ready to convert and selecting a different item.

As you begin exploring your fry options, there are a number of things you will want to consider:

Will your customers notice a difference in the taste and texture of your fries?

If customers notice a difference, will they like the new product as well as or better than your current offering?

Will the change in parfry oils result in any operational differences – such as the "clumping" of frozen fries, the leaching of oil onto packaging, or increasing levels of "dust" or crumbs in the fryers that cause the oil to break down faster?

Are other items being prepared in the same fryers that will add trans fat to the fryer oil and cause your fries to pick up trans fat?

Will there be a difference in cost or issues with availability?

Will there be other nutrition trade-offs in order to reduce the levels of trans fats?

Will your larger serving sizes provide zero grams trans fat per serving?

While the food industry is constantly evaluating the ever-growing number of new oil options available, so far most fry manufacturers are using one or both of two major approaches for the parfry step. The first approach is to use either a single liquid vegetable oil, such as canola or blend of similar oils. The second approach is to use a blend of liquid oils and more stable fat. The more stable fat may be lightly hydrogenated liquid oil (a lower trans option, but not necessarily qualifying as zero grams trans), fully hydrogenated oil or a vegetable oil that is solid at room temperature, such as palm oil. All of these approaches have pros and cons.

Liquid vegetable oils will provide very low trans fat levels, generally two percent trans fatty acids or lower. Trans fat may be present in all edible oils that are created when raw oils are processed for human consumption. The levels are low enough per serving that the oils can be labeled as "zero grams trans fat," per the applicable FDA regulation. In addition, liquid oils, such as canola, may provide lower saturated fat levels in parfried products than partially hydrogenated oils, which is a positive health benefit. However, liquid vegetable oils are less stable than partially hydrogenated oils. The lower stability may cause the "clumping" of frozen product, the leaching of oil into the packaging, and reduced fryer oil life due to increased crumbs and "dust" left in the fryer oil. Because these oils are liquid at room temperature, the outer texture of the fries may not be as crisp. In addition, some liquid vegetable oils may impart flavors unique to those oils.

Lightly hydrogenated oil blends include a mixture of liquid oils with partially hydrogenated oils. The combination may provide much of the stability associated with partially hydrogenated oils. However, the product labels still may include partially hydrogenated oil. Also, due to higher trans fat levels in these oils than in straight liquid vegetable oils, the maximum portion size that will qualify as zero grams trans fat per serving will be smaller.

Fully hydrogenated oils occur when liquid vegetable oils are hydrogenated fully, producing saturated fats rather than trans fats. In general, these oils mirror many of the stability characteristics of partially hydrogenated oils. Saturated fat content will generally be higher than liquid oils such as canola.

Oil blends that composed of a mixture of liquid vegetable oils and vegetable oils that are solid at room temperature, such as palm oil, eliminate many of the issues associated with liquid oils alone. These blends generally will have higher saturated fat levels than canola oils, but can be blended to remain neutral for saturated fat content when compared with partially hydrogenated oils.

All of the options available will require some trade-offs. The best solution for your operation will be the product that requires the fewest trade-offs in the areas that are the most important to you. Talk to your manufacturers. Test products in your own operations. Most importantly, if you are claiming zero grams trans fat per portion, check the trans fat levels in your prepared products in real situations – at the beginning of oil life, partway through the oil life cycle, and at the end of your fryer oil life cycle to ensure that nothing that is increasing the trans fat levels beyond zero grams per serving.



Texas A&M has completed the testing of ten oils in the zero trans fat cooking oil contest. The results are posted on the List of Oils & Results page.

Contest Pictures

Click on the image below to see pictures of the oil contest.