You're still going to have do a bit of sleuth work to find out whether there are GMOs in your food. 

President Obama Friday signed a bill that nullifies state genetically modified organism labeling laws, including the nation's first, Vermont's that went into effect July 1. The new federal law may only require labeling for some GMO products. The law obligates food manufacturers to give consumers information on the GMOs in their products, but they don’t have to do so on the package. 

Instead of the requisite “produced with genetically engineered ingredients” language set in Vermont’s law, manufacturers can instead produce a label with a QR code, which you need to scan with a smartphone, or tell consumers to try a toll-free phone number.

The final rules manufacturers will have to follow won’t be out for at least two years. 

Support for Vermont’s law forced anti-GMO labeling lawmakers and the food industry to give up their hopes of banning any form of mandatory GMO labeling. In March, a bill that would have made GMO labeling voluntary, dubbed the DARK (Deny Americans the Right To Know), was defeated in the Senate

And this year, several major food companies, such as Campbell Soup and General Mills, announced they would label products containing genetically engineered ingredients. 

“Those changes would not have happened if concerned consumers did not keep the heat on,” says Jean Halloran, director of food policy for Consumers Union, the policy and mobilization arm of Consumer Reports. “And consumers who support on-package labels should be sure to let the companies that have already started labeling GMOs  know that they still expect labeling to continue.” 

Campbell and Mars, Inc told Consumerist that they will continue with on-package GMO labeling. General Mills and Nestle were less clear about their plans, and PepsiCo did not respond to a request for comment.

So here are five tips to help you find food without GMOs:

1. Two labels that indicate a product has no GMOs

Foods that carry the United States Department of Agriculture's 100 percent organic seal usually don’t contain GMO ingredients, but the agency does not test products to verify this. The Non-GMO Project Verified seal is even more reliable because the organization verifies that the product not have more than 0.9 percent genetically modified ingredients. In 2014, Consumer Reports tested different foods for the presence of GMOs. We found that no food with the USDA organic or the GMO Project Verified Seal contained more than 0.9 percent GMOs.

2. Corn and soy are the major GMO crops in the U.S.

According to our 2014 tests, a food had GMOs if a corn- or soy-containing product in it was not organic and did not carry the Non-GMO Project Verified seal or another non-GMO claim. These included: baking mixes, corn cereal, granola bars, tortillas, tortilla chips, soy-based infant formulas, soy milk, tofu, and veggie burgers. Canola oil often includes GMOs, too. Assume that any product made with these three ingredients are genetically modified unless the label says otherwise.

A survey by Mintel, a market research firm, found that 19 percent of fruit eaters are concerned about GMOs in their fruit. But just one fruit currently on the market—papaya from Florida or Hawaii—can be genetically modified. And while you may have heard of genetically modified tomatoes, those are no longer being sold. Vegetables that could be genetically modified are some varieties of summer squash (like zucchini), some potatoes grown in Idaho and Washington, and some sweet corn, although most sweet corn is not grown from genetically modified seeds. 

A GMO variety of apple that doesn’t brown has gone through Food and Drug Administration’s voluntary safety consultation process and the FDA has approved genetically modified salmon, but neither   product is on the market yet. 

3. Sugar can be GMO

Much of the sugar in America’s sugar bowls and processed foods—not only baked goods, soda, and sweets, but also foods such as bread, cereal, soups, and yogurt—come from sugar beets and 99 percent of that crop is genetically modified. High fructose corn syrup is often genetically modified too, as is the artificial sweetener aspartame. Agave, cane sugar, molasses, and turbinado sugar, however, are never genetically modified. 

4. GMOs can surprise you

Canola, corn, and soy are in a lot of foods. So are ingredients derived from them, such as baking powder, beta carotene, cellulose, citric acid, corn starch, lactic acid, lecithin, riboflavin, miso, soybean oil, soy protein, soy sauce, vitamin E (tocopherol), and xanthan gum.  

5. You need to be GMO label savvy

Non-GMO labels can be found on foods that are never genetically modified, such as canned beans and vegetables, chicken, eggs, oatmeal, quinoa, and tuna. Why? Sometimes it is just marketing, but in other cases there’s a reason. For instance, when you see the Non-GMO Project Verified seal on eggs or chicken, it means there are no genetically modified ingredients in the animals’ feed.

Sugar or thickeners, like corn starch, may be added to canned beans and vegetables and tuna is often packed in soy oil. A non-GMO label means those ingredients are absent or are non-GMO.

Still, if you like a particular brand or the brand without the non-GMO claim is less expensive than another, check the ingredients list. If the product doesn’t contain canola, corn, soy, or sugar—or ingredients derived from them—you can feel reasonably certain that it does not have GMOs.