While researching something else I came across these articles and found them interesting. Although the method described won't work for many households in the PI's as they don't have refrigerators, it still may be viable for many of us. I'm also not sure if it'll work (or rather be as effective) if you cook your rice in an electric rice cooker, but I'm sure it wouldn't hurt.
Note that the researcher of the second article about the rice the got idea from the research conducted about pasta. It made me wonder if adding a couple of teaspoons of coconut oil (a staple in my pantry along with extra virgin olive oil) to the water before boiling the pasta would be even more beneficial then the method described below. I usually add some olive oil to the water - even though science has proven that it does not help keep pasta from sticking once cooked, it's how my grandmother taught me and old habits die hard :). As it is, I often reheat in a microwave or pan fry day old pasta and think it tastes better then when freshly cooked.
Is reheated pasta less fattening?
16 October 2014
Share this with Facebook
Share this with Messenger
Share this with Twitter
Share this with Email
Many food-lovers worry about pasta making them fat. But could simply cooling and then reheating your meal make it better for you, asks Michael Mosley.There are few things that really surprise me about nutrition, but one of the experiments from the latest series of Trust Me, I'm a Doctor really did produce quite unexpected results
Many food-lovers worry about pasta making them fat. But could simply cooling and then reheating your meal make it better for you, asks Michael Mosley.
There are few things that really surprise me about nutrition, but one of the experiments from the latest series of Trust Me, I'm a Doctor really did produce quite unexpected results.
You are probably familiar with the idea that pasta is a form of carbohydrate and like all carbohydrates it gets broken down in your guts and then absorbed as simple sugars, which in turn makes your blood glucose soar.
In response to a surge in blood glucose our bodies produce a rush of the hormone insulin to get your blood glucose back down to normal as swiftly as possible, because persistently high levels of glucose in the blood are extremely unhealthy.
A rapid rise in blood glucose, followed by a rapid fall, can often make you feel hungry again quite soon after a meal. It's true of sugary sweets and cakes, but it's also true for things like pasta, potatoes, white rice and white bread. That's why dietitians emphasize the importance of eating foods that are rich in fibre, as these foods produce a much more gradual rise and fall in your blood sugars.
But what if you could change pasta or potatoes into a food that, to the body, acts much more like fibre? Well, it seems you can. Cooking pasta and then cooling it down changes the structure of the pasta, turning it into something that is called "resistant starch".
It's called "resistant starch" because once pasta, potatoes or any starchy food is cooked and cooled it becomes resistant to the normal enzymes in our gut that break carbohydrates down and releases glucose that then causes the familiar blood sugar surge.
So, according to scientist Dr Denise Robertson, from the University of Surrey, if you cook and cool pasta down then your body will treat it much more like fibre, creating a smaller glucose peak and helping feed the good bacteria that reside down in your gut. You will also absorb fewer calories, making this a win-win situation.
One obvious problem is that many people don't really like cold pasta. So what would happen if you took the cold pasta and warmed it up?
When we asked scientists this question they said that it would probably go back to its previous, non-resistant form, but no-one had actually done the experiment. So we thought we should.
Dr Chris van Tulleken roped in some volunteers to do the tests. The volunteers had to undergo three days of testing in all, spread out over several weeks. On each occasion they had to eat their pasta on an empty stomach.
The volunteers were randomised to eating either hot, cold or reheated pasta on different days.
On one day they got to eat the pasta, freshly cooked, nice and hot with a plain but delicious sauce of tomatoes and garlic. On another day they had to eat it cold, with the same sauce, but after it had been chilled overnight. And on a third day they got to eat the pasta with sauce after it had been chilled and then reheated.
On each of the days they also had to give blood samples every 15 minutes for two hours, to see what happened to their blood glucose as the pasta was slowly digested.
Well we were fairly confident the cold pasta would be more resistant than the stuff that had been freshly cooked and we were right.
Just as expected, eating cold pasta led to a smaller spike in blood glucose and insulin than eating freshly boiled pasta had.
But then we found something that we really didn't expect - cooking, cooling and then reheating the pasta had an even more dramatic effect. Or, to be precise, an even smaller effect on blood glucose.
In fact, it reduced the rise in blood glucose by 50%.
This certainly suggests that reheating the pasta made it into an even more "resistant starch". It's an extraordinary result and one never measured before.
Denise is now going to continue her research - funded by Diabetes UK - looking at whether, even without other dietary modifications, adding resistant starch to the diet can improve some of the blood results associated with diabetes.
Chris was certainly blown away by this finding.
"We've made a brand new discovery on Trust Me I'm A Doctor", he says, "and it's something that could simply and easily improve health. We can convert a carb-loaded meal into a more healthy fibre-loaded one instead without changing a single ingredient, just the temperature. In other words our leftovers could be healthier for us than the original meal."
PUBLIC RELEASE: 23-MAR-2015
New low-calorie rice could help cut rising obesity rates
AMERICAN CHEMICAL SOCIETY
DENVER, March 23, 2015 -- Scientists have developed a new, simple way to cook rice that could cut the number of calories absorbed by the body by more than half, potentially reducing obesity rates, which is especially important in countries where the food is a staple.
The presentation will take place here at the 249th National Meeting & Exposition of the American Chemical Society (ACS), the world's largest scientific society. The meeting features nearly 11,000 reports on new advances in science and other topics. It is being held through Thursday.
The number of people who are overweight or obese is steadily increasing. As lifestyles change and people become more sedentary, their diets also change. Serving sizes grow, and more food options become available. In addition to consuming more fats and sugars, people may choose to fill up on starchy carbohydrates like rice, which has about 240 calories per cup.
"Because obesity is a growing health problem, especially in many developing countries, we wanted to find food-based solutions," says team leader Sudhair A. James, who is at the College of Chemical Sciences, Colombo, Western, Sri Lanka. "We discovered that increasing rice resistant starch (RS) concentrations was a novel way to approach the problem." By using a specific heating and cooking regimen, he says, the scientists concluded that "if the best rice variety is processed, it might reduce the calories by about 50-60 percent."
He explains that starch can be digestible or indigestible. Starch is a component of rice, and it has both types. Unlike digestible types of starch, RS is not broken down in the small intestine, where carbohydrates normally are metabolized into glucose and other simple sugars and absorbed into the bloodstream. Thus, the researchers reasoned that if they could transform digestible starch into RS, then that could lower the number of usable calories of the rice.
And rice is loaded with starch (1.6 ounces in a cup), says James. "After your body converts carbohydrates into glucose, any leftover fuel gets converted into a polysaccharide carbohydrate called glycogen," he explains. "Your liver and muscles store glycogen for energy and quickly turn it back into glucose as needed. The issue is that the excess glucose that doesn't get converted to glycogen ends up turning into fat, which can lead to excessive weight or obesity."
The team experimented with 38 kinds of rice from Sri Lanka, developing a new way of cooking rice that increased the RS content. In this method, they added a teaspoon of coconut oil to boiling water. Then, they added a half a cup of rice. They simmered this for 40 minutes, but one could boil it for 20-25 minutes instead, the researchers note. Then, they refrigerated it for 12 hours. This procedure increased the RS by 10 times for traditional, non-fortified rice.
How can such a simple change in cooking result in a lower-calorie food? James explains that the oil enters the starch granules during cooking, changing its architecture so that it becomes resistant to the action of digestive enzymes. This means that fewer calories ultimately get absorbed into the body. "The cooling is essential because amylose, the soluble part of the starch, leaves the granules during gelatinization," explains James. "Cooling for 12 hours will lead to formation of hydrogen bonds between the amylose molecules outside the rice grains which also turns it into a resistant starch." Reheating the rice for consumption, he notes, does not affect the RS levels.
He says that the next step will be to complete studies with human subjects to learn which varieties of rice might be best suited to the calorie-reduction process. The team also will check out whether other oils besides coconut have this effect.