Category Archives: Food

Is Sugar in Fruit Different Than Sugar in Soda?

Sugar. Everyone loves a sweet treat, but sugar has found its way into savory foods like pasta sauce and bread. On average, Americans eat nearly 66 pounds of added sugar per person per year. It’s easy to exceed the daily recommended sugar intake when a 12 oz soda has about 11 teaspoons of added sugar.  But what about the sugar in fruit?  Should people be worried about how much fruit they’re eating? Kimber Stanhope, a Nutritional biologist at UC Davis, walks us through the science.

Sugar doesn’t just add to our waistlines, it is linked to chronic conditions like heart disease and diabetes. There is also growing scientific consensus that one of the most common types of sugar, fructose (found in high-fructose corn syrup and table sugar) can be toxic to the liver, just like alcohol.

Is fruit juice better for you than soda?   

Dr. Stanhope gets asked this a lot. The short answer is that no one really knows for sure.

“…it drives me crazy that I don’t know the answer for sure. I have not found any studies in the scientific literature that have actually compared the consumption of a sugar-sweetened beverage to a fruit juice-sweetened beverage for more than one day. So we’re going to do a 2-week study…one group will be getting fruit juice (orange juice), the other group will get a sucrose-sweetened beverage. And I think it’s very important that this study gets done because there are many scientists out there that have made the assumption that fruit juice is just as bad as sucrose [because they’ve taken out the fiber in fruit], and they might be right, but I don’t know. There is evidence in the literature, epidemiological studies, that suggest that fruit juice is protective compared to a sugar-sweetened beverage, and there is also a couple of studies that suggest they’re just as bad. We need to know.”

Stanhope points out that the answer may even differ for each type of fruit juice (grapefruit juice, apple juice, orange juice, etc.).  She hopes to study the question in more detail once the preliminary results come in.

More information at sugarscience.org

Make The Best Pie Ever Using Science

One of the staples of the holiday season is pie and while you may have Grandma’s recipe for the perfect crust, do you really know what goes on at a molecular level? UCLA biophysicist Amy Rowat shares some of the scientific aspects of apple pie and explains how you can apply these insights in the kitchen.

1.    Think of butter as a gas.

Butter is really just a bunch of teeny tiny water droplets dispersed in a matrix of fat. In the oven, these water droplets convert from liquid to gas. This means that the chunks of butter you can see in your dough are really just big pockets of air waiting to happen. More air = flakier crust! While butters with the highest butterfat content are generally synonymous with the highest quality butter, when it comes to baking pie a slightly lower fat content, and higher water content, may be a good thing.

2.    Experiment with the liquids you add to your pie dough
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Gluten gives structure and stability to pie dough, but can also make pie dough dense and tough when over-developed. Typically water is added to create pie dough, but you can experiment with different liquids —like vodka, rum or even carbonated water— that impede the formation of gluten protein networks.

 3.    Sometimes the best pie is a day-old pie.
Temperature is important for pie texture. Because molecules flow more quickly past each other at higher temperatures, hot pie filling straight from the oven will be more runny; as the pie filling cools, starchy molecules like cornstarch and flour spend more time interacting with each other. As the pie cools, the pectin molecules of your fruit also spend more time interacting with each other. This results in a more solid, gel-like filling that will take longer to seep out of the pie when it is cut and served on a plate.

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Do gut bacteria rule our minds?

Gut Bacteria

It sounds like science fiction, but it seems that bacteria within us — which outnumber our own cells about 100-fold — may very well be affecting both our cravings and moods to get us to eat what they want, and often are driving us toward obesity.

In an article published this week in the journal BioEssays, researchers from UC San Francisco, Arizona State University and University of New Mexico concluded from a review of the recent scientific literature that microbes influence human eating behavior and dietary choices to favor consumption of the particular nutrients they grow best on, rather than simply passively living off whatever nutrients we choose to send their way.

Bacterial species vary in the nutrients they need. Some prefer fat, and others sugar, for instance. But they not only vie with each other for food and to retain a niche within their ecosystem — our digestive tracts — they also often have different aims than we do when it comes to our own actions

Read more about the manipulative bacteria in our gut

Building a better cup of coffee

A cup of coffee

The brave new world of coffee? Think genetics.

UC Davis geneticist Juan Medrano is known for his research on the genetics of milk (and the effect it has on humans), but recently has turned his research efforts towards coffee.

The goal is to understand the variability of coffee genes at the DNA level. This would allow Medrano and others to accurately identify genetic forces that contribute to certain flavors as well as the crucial factor of disease resistance.

The key is to identify the gene regulators that are related to flavor and other qualities, such as how coffee feels in the mouth. Gene regulators are involved in controlling the expression of other genes.

Other variables, like altitude, can be crucial in coffee growing. Coffee flavor and aromas change significantly with changes in altitude, as temperature and microclimates vary greatly. The higher-altitude coffees are generally of better cupping quality, Medrano explains.

Read more

Fake olive oil? To get the benefits of olive oil, it’s got to be fresh

Olive Oil - Olive Oyl

The Mediterranean diet has become a darling of medical researchers.  It’s known for its veggies and grains, limited amounts of meat, and a good helping of olive oil.

Researchers believe that olive oil is the key to the superior health benefits of the Mediterranean diet.

“The health benefits of olive oil are 99% related to the presence of the phenolic compounds, not the oil itself,” explains Nasir Malik, a researcher at the U.S. Department of Agriculture. [1]

Polyphenols decrease heart disease risk factors by lowering blood pressure and cholesterol, reducing blood clotting and improving the health of artery linings. They also reduce cancer risk by lowering inflammation and cellular proliferation. They even reduce microbial activity and infections.

Sounds great, right? But here’s the catch…

When tested, polyphenols were surprisingly low in most commercially available olive oils.

It turns out that 69% of the “extra-virgin” olive oil imported into the U.S. has been shown to be substandard, according to a study out of UC Davis.

Often, the oil is just too old. It’s shipped from place to place before it’s imported and usually isn’t stored well.  By the time it arrives in the U.S., Many of the heart-health compounds have degraded and fizzled out.

Here’s what to look for:

  • Harvest date on the label: The bottle should have a “harvest date” instead of a “sell by” label. The olives should be harvested within the past year.
  • The container: Buy olive oil in a container that protects it from the light (dark glass or tin).
  • The taste & smell: If the oil stings the back of your throat a little that tells you the beneficial polyphenols really are there. High-quality olive oil is pungent and often described as “grassy” or “peppery.”

The brands that failed to meet the extra virgin olive oil standards, according to this study: Bertolli, Carapelli, Colavita, Star, Pompeian. [2]

The real deal: California Olive Ranch, Cobram Estate, Lucini. (Kirkland Organic, Lucero (Ascolano), McEvoy Ranch Organic are also noted by Eat Grown Local.)

Eat. Think. And be wary.

Picture 2013-09-11 at 11.35.41 AM

Bologna dropped on a kitchen floor can bear an unsettling resemblance to Petri dishes containing Salmonella bacteria.

Eat. Think. And be wary.

Most folks know the “five-second rule,” an unwritten convention that says if you drop a food item on the floor it may be picked up, dusted off and safely consumed within that designated amount of time.

Apparently this assumes microbes need at least six seconds to make the jump.

In recent years, the scientific integrity of the five-second rule has come under occasional empirical scrutiny.

Read more about the research here

The “Pope of Foam” and the science behind beer


UC Davis brewing science professor Charles Bamforth is known as the “pope of foam.” His lab delves into the science behind creating the perfect beer foam, which is essential to a great tasting brew. That’s because most of the flavor of beer is detected by smell, which is why Bamforth says you must drink beer from a glass and not straight from a bottle or can. He explains beer-making and reveals how to pick the freshest pint when you’re at a pub.