Impregnating soybean flour with antioxidant-rich blueberry or cranberry extracts may open up new dietary supplement and functional food opportunities for industry, suggests new research.
According to finding published in Food Chemistry, 1.4 grams of blueberry-impregnated defatted soybean flour provides the same polyphenol content as 73 grams of fresh blueberries.
Similarly, 1 gram of the cranberry-impregnated defatted soybean flour has the equivalent polyphenol content as three 8 ounce glasses of cranberry juice.
“This process of capturing, concentrating and preserving beneficial bioactive compounds from plants onto natural edible matrices, such as defatted soybean flour, has the potential to create a new category of naturally fortified and scientifically validated food, dietary supplement (delivered as capsules or tablets) and cosmetic ingredients,” explained researchers from Rutgers University and North Carolina State University.
“Phytochemical-enriched natural matrices incorporated into familiar foods would provide a practical and convenient means of increasing dietary consumption of beneficial phytochemicals, such as polyphenols, and may be useful for the prevention and treatment of chronic and age-related disease.”
Presenting some of his group’s findings at the SupplySide West event in Las Vegas, lead researcher Dr Ilya Raskin explained that the team is working with industrial partners to further develop the Nutrasorb technology.
Dr Ruskin and his co-workers also examined the effects of consumption of the berry-enriched soybean flour in mice, and found that the blueberry version displayed significant activity in lowering blood sugar levels.
On the other hand, in vitro studies with the cranberry-enriched flour revealed anti-microbial and anti-UTI activities.
The new process centered on the absorption of polyphenols from blueberry and cranberry juices onto defatted soybean flour while simultaneously separating them from sugars.
A very simple mixing of the flour and the juice was performed, followed by centrifuging to separate the juice from the enriched flour, and then filtering.
Results showed that as much as 22 milligrams of blueberry anthocyanins could be sorbed on one gram of the soybean flour, while up to 95 grams of total polyphenols could be sorbed on the same one gram of flour.
In addition, the anthocyanin and polyphenol concentration on the soybean flour was found to remain constant during 22 weeks of storage at 37°C.
“Most fresh fruits and vegetables are highly perishable and must be consumed within a few days unless refrigerated, frozen, dehydrated or preserved, therefore the defatted soybean flour-sorption technology can be used to deliver the phytochemical benefits of fresh produce in a portable and shelf-stable format,” explained the researchers.
“Furthermore, this technology platform may be useful to capture bioactive phytochemicals from non-palatable plant parts, such as skins and peels, which are usually discarded.
“This process requires no chemical solvents or costly synthetic ion-exchange and affinity resins and creates value-added, nutritious, low-sugar protein-rich food ingredients,” they concluded.
Source: Food Chemistry
Published online ahead of print, doi: 10.1016/j.foodchem.2011.09.103
“Efficient sorption of polyphenols to soybean flour enables natural fortification of foods”
Authors: D.E. Roopchand, M.H. Grace, P. Kuhn, D.M. Cheng, N. Plundrich, A. Poulev, A. Howell, B. Fridlender, M.A. Lila, I. Raskin