Alcohol-Free Berry “Wine” Could Potentially Reduce Type 2 Diabetes

Blueberries and berries in general, are labeled as “diabetes superfoods” by the American Association of Diabetes. And now food science researchers at the University of Illinois (UoI) have discovered that fermenting berries may improve their antidiabetic potential even more.

 

“Unfortunately the number of people with diabetes is increasing astronomically around the world,” says Elvira de Mejia, a food chemist in the department of food science and human nutrition at UoI. “There are 100 million people around the world who have diabetes and that is increasing, without counting the ones who may be pre-diabetic and not know it.”

 

Previous research has demonstrated that dietary blueberries may play a role in reducing hyperglycemia in obese mice, therefore de Mejia and her team wanted to see if a fermented, de-alcoholized blueberry-blackberry beverage would enhance the potential of the phenolic compounds in the berries, as these are the compounds responsible for reducing diabetic markers.

 

Indeed, the new study shows just that: The fermented berry beverage did reduce the development of obesity and blood glucose levels in mice on a high-fat diet.

 

“We know that fruits, vegetables, cereals, legumes and berries are good, but here we explain that after fermentation we improve and increase the concentration of these pigments (anthocyanins) and they are very high antioxidant components that benefit the body,” adds de Mejia.

 

The research team already knew that when the berries were fermented at low temperatures there was an improved and higher concentration of anthocyanins, the likes of which found in the pigments of fruits including blueberries, grapes and apples, have been shown to promote insulin sensitivity, decrease blood glucose levels in the blood and enhance insulin secretion.

 

A cell culture study with the alcohol-free blueberry wine showed good results towards inhibiting enzymes related to glucose absorption.

 

“In this in vivo study, as we increased the concentration of these anthocyanin-enriched extractions from blueberries and blackberries we saw an improvement in the uptake of glucose, meaning that the animals with the increased concentration were not as much in a state of hyperglycemia as the other animals.”

 

The alcohol-free berry wine was made up of 70 percent fermented blackberries to 30 percent fermented blueberries, all of which were grown from varieties cultivated at the University’s Dixon Springs Agricultural Research Station. Alcohol was removed from the drink by rotoevaporation and was replaced with water, whilst some of the sugars left over after fermentation were also removed in the process.

 

“We optimized the best ratio between blueberries and blackberries. Blackberries are very unique and I think that’s one of the reasons why we selected a high concentration of them in this study. Blackberries have a very specific profile of anthocyanins, and that was amazing at lowering the absorption of glucose in this case.”

 

The study involved groups of mice with diet-induced obesity and hyperglycemia being given the fermented berry beverage or the beverage with higher or lower enriched concentrations of the anthocyanins (0.1x, 1x, or 2x). Another group was given sitagliptin, a commonly used diabetes medication, and another group was just given water. Otherwise, all groups of mice ate the same diet, calories and amount of sugars.

 

Benefits were seen across all groups consuming the fermented beverage, but the group on the highest concentration of anthocyanins (2x) showed the greatest results, including no increase in body weight.

 

“That was not our objective really, we were just looking for markers of diabetes. But it was very impressive to see,” de Mejia continues.

 

“You want to avoid high glucose in the blood stream, and you want uptake into muscle, liver, and organs, and to keep the level in plasma and blood normal. We saw a reduction of glucose in the blood with the beverage, even in the beverage before it was enhanced.”

 

“We saw that in the animals on 2x the enriched anthocyanins, the oxidative species went down, meaning they were kind of protected against oxidation. From that standpoint, it was very positive looking at the oxidate stress of the animals because that can damage protein and DNA.”

 

There is potential for winemakers to produce this type of berry alcohol-free berry wine, according to de Mejia.

 

“There are some bigger wineries/companies that are producing dealcoholized wine for diabetics, but from grapes. It is available in California for example. I think the novelty of this work is mainly the combination of the blackberries and blueberries and the concentration of anthocyanins as part of the pigment. But it is perfectly doable and I hope that companies can see that there is a market. And it’s delicious.”

 

“There needs to be more studies to see how the anthocyanins work in the presence of medication, to see if they would work synergistically, for example. Then, maybe, you could decrease the amount of the drug. All of these drugs for diabetes have adverse effect after so many years of use, even the safest ones.’

 

“We need to consider diet, exercise, lowering body weight and all the different strategies that the American Association of Diabetes recommends, and maybe in the long run, of course with the approval of a physician, you could decrease the level of the drug to keep glucose under control.”