If I hadn't known about a new study of yogurt for properties that can help us keep our diabetes and high blood pressure in check, I wouldn't be enjoying soy yogurt now.
I love yogurt, but have preferred a dairy product, plain nonfat yogurt from Straus Family Creamery, a family-owned farm just north of San Francisco. This yogurt is surprisingly thick for being nonfat. It is also quite sour, but is delicious when I add a non-caloric sweetener.
After eating more than my share of soy cheese, I couldn't imagine that soy yogurt could taste anything like the real thing. I was wrong, at least for two of the three soy yogurts that I was able to find in the places where I buy my food, Whole Foods and Wild Oats, the two biggest natural food chains.
Two soy yogurts taste great and offer health benefits. One comes from WholeSoy & Co., an independently owned company in San Francisco. The other comes from Stonyfield Farms, in Londonderry, New Hampshire. The French food giant, Groupe Danone, owns 85 percent of Stonyfield Farms. Both Whole Foods and Wild Oats carry these delicious soy yogurts.
On the other hand, Silk Soy Yogurt tastes too much like soy. It's not at all smooth or creamy. The carton says that it comes from Boulder, Colorado, where I live. But Silk is actually a subsidiary of White Wave Foods, which in turn is a subsidiary of another food giant, Dean Foods Company of Dallas.
If this sounds like a corporate takeover of the organic foods industry, you haven't begun to see how far it's gone. If you study a chart on Organic Industry Structure developed by the Organic Consumers Association, you might be surprised.
The only brand of soy yogurt tested in the new study was the great tasting WholeSoy yogurt from the small San Francisco company. Dr. Kalidas Shetty, professor of food biology in the University of Massachusetts's department of food science, spoke to me about his research. He also kindly sent me a pre-print of his study, "Potential of Select Yogurts for Diabetes and Hypertension Management that the Journal of Food Biochemistry will publish in an upcoming issue.
Dr. Shetty and his associates also bought three brands of dairy yogurt in a local supermarket. The brands were Dannon (the name that Group Danone uses in the U.S.), Stonyfield, and Stop 'n Shop, the house brand of a New England supermarket chain.
What the scientists looked for was activity of enzymes that help to moderate blood glucose levels. They found that fruit-enriched yogurts - especially those made with soy or blueberries - have active natural compounds that may help us to control our diabetes.
Blocking two of these enzymes - alpha-amylase and alpha-glucosidase - slow the body's absorption of carbohydrates. Blocking another enzyme - angiotensin-I converting enzyme or ACE-I - helps to control high blood pressure, which many people with diabetes have.
Earlier research by Dr. Shetty and his associates and others found that certain plant compounds play a role in blocking all three of these enzymes. They decided to study how well yogurt can block these enzymes, Dr. Shetty told me, because the "probiotics" in yogurt can treat gastrointestinal disorders and improve immune function.
Probiotic foods are principally buttermilk, yogurt, and kefir. They all contain friendly bacteria.
When Dr. Shetty told me that blueberry yogurt ranked high in their study, I wasn't surprised. Blueberries are among the best foods in terms of their oxygen radical absorbance capacity, which quantifies the antioxidant capacity of foods and prevents oxidative stress.
But as good as blueberries are as an antioxidant, Dr. Shetty told me that their study was broader. They screened dairy and soy yogurt for especially for the inhibition of the three enzymes I mention above. But they also tested the yogurts to see how much phenols they have. Many plants contain phenols, which seem to be good for us because they are antioxidants.
Soy yogurt - even plain soy yogurt - ranks highest in phenols. Blueberry yogurts have more phenols than strawberry, peach, or plain yogurt. In fact, plain dairy yogurt has the lowest total phenolic content, because it doesn't have any fruit extracts.
Blueberry extracts are the best at blocking the action of alpha-glucosidase. Strangely, Dr. Shetty's team didn't find any correlation between alpha-amylase and any specific type of yogurt, whether it was plain, soy based, or fruit enriched. However, soy yogurts, followed by fruit-enriched yogurts, are clearly the best at inhibiting the ACE-I enzyme.
Of the yogurts they studied WholeSoy blueberry yogurt looks to me like the best. But it also has 26 grams of available carbohydrates in a small 170 gram container, most coming from "organic evaporated cane juice," which is essentially sugar.
My wife suggests that we get plain soy yogurt, mix in fresh or frozen blueberries, and then add with a non-caloric sweetener. Nobody seems to have studied that yet, but I am willing to bet that it would be better for us than even the best brands that Dr. Shetty and his group tested.