Frozen blueberries pack more powerful antioxidant punch
Blueberries pack a powerful antioxidant punch, whether eaten fresh or from the freezer, according to South Dakota State University graduate Marin Plumb.
Measuring the phenolic content of the pigments in frozen vs. fresh blueberries gives the researchers a better idea of the fruit’s antioxidant capacity.
Anthocyanins, a group of antioxidant compounds, are responsible for the color in blueberries, she explains. Since most of the color is in the skin, freezing the blueberries actually improves the availability of the antioxidants.
The food science major from Rapid City, who received her bachelor’s degree in December, did her research as part of an honors program independent study project.
“Blueberries go head to head with strawberries and pomegranates in antioxidant capacity,” said professor Basil Dalaly, Plumb’s research adviser. In addition, blueberries are second only to strawberries, in terms of the fruits Americans prefer.
Blueberries are beneficial for the nervous system and brain, cardiovascular system, eyes and urinary tract, Dalaly explained. “Some claim it’s the world’s healthiest food.”
The United States produces nearly 84 percent of the world’s cultivated blueberries, an estimated 564.4 million pounds of blueberries in 2012, according to the Agricultural Marketing Resource Center.
Since blueberries are frozen soon after they are picked, “they are equal in quality to fresh,” Plumb explained. She analyzed the anthocyanin content of blueberries frozen for one, three and five months and found no decrease in antioxidants over fresh berries.
The leaching that occurs from freezing actually increased the anthocyanin concentration, noted Plumb. “The ice crystals that form during freezing disrupt the structure of the plant tissue, making the anthocyanins more available.”
Antioxidants, such as anthocyanins, eliminate free radicals, which are produced through common biological reactions within the body and outside factors such as the sun, pesticides and other pollutants, Dalaly explained. If left to roam free, these free radicals can attack DNA, proteins and lipids resulting in cellular changes that lead to development of diseases such as cancer.
“They have a domino effect,” Dalaly said. “That is why we need to consume at least seven to nine servings of fruits and vegetables a day.”
He teaches a course on phytochemicals—the naturally-occurring chemical compounds in fruits and vegetable, many of which have the potential to boost the immune system and impact diseases, such as cancer and heart disease. His advice is simple: “the greener, or redder, the better.”
Plumb called her undergraduate research project “a very good experience,’ noting that she learned to both ask and answer questions such as “why is this happening this way?” One of the surprises was that she had to use blueberries from Canada and Argentina because they were in season when she did her experimental work.
Plumb concluded: “Blueberries are a great food, very good for you.”
Food Science Program
Food science prepares students for professional positions in the food manufacturing industry or for graduate study. Food scientists apply science to the selection, preservation, processing, packaging, and distribution of food and use creative to develop new food products. Students train in state-of-the-art laboratory facilities. The program offers attractive internship opportunities within the food industry including international experiences. The food industry is searching for individuals interested in product development, technical sales, quality control and research.
About South Dakota State University
Founded in 1881, South Dakota State University is the state’s Morrill Act land-grant institution as well as its largest, most comprehensive school of higher education. SDSU confers degrees from eight different colleges representing more than 175 majors, minors and specializations. The institution also offers 29 master’s degree programs, 13 Ph.D. and two professional programs.
The work of the university is carried out on a residential campus in Brookings, at sites in Sioux Falls, Pierre and Rapid City, and through Cooperative Extension offices and Agricultural Experiment Station research sites across the state.
Christie Delfanian | newswise
Penn study identifies viral product that promotes immune defense against RSV
04.09.2015 | University of Pennsylvania
Columbia Engineering team develops targeted drug delivery to lung
03.09.2015 | Columbia University School of Engineering and Applied Science
In a survey of NASA's Hubble Space Telescope images of 2,753 young, blue star clusters in the neighboring Andromeda galaxy (M31), astronomers have found that M31 and our own galaxy have a similar percentage of newborn stars based on mass.
By nailing down what percentage of stars have a particular mass within a cluster, or the Initial Mass Function (IMF), scientists can better interpret the light...
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE have developed a highly compact and efficient inverter for use in uninterruptible power...
China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from University of Arizona geoscientists. The study is the first to explain how the steep-fronted plateau formed.
China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from...
The leaves of the lotus flower, and other natural surfaces that repel water and dirt, have been the model for many types of engineered liquid-repelling surfaces. As slippery as these surfaces are, however, tiny water droplets still stick to them. Now, Penn State researchers have developed nano/micro-textured, highly slippery surfaces able to outperform these naturally inspired coatings, particularly when the water is a vapor or tiny droplets.
Enhancing the mobility of liquid droplets on rough surfaces could improve condensation heat transfer for power-plant heat exchangers, create more efficient...
Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening to transform some of the world's temperate forests, a new study published in Science has found. Without informed management, some forests could convert to shrublands or grasslands within the coming decades.
"While we have been trying to manage for resilience of 20th century conditions, we realize now that we must prepare for transformations and attempt to ease...
03.09.2015 | Event News
20.08.2015 | Event News
20.08.2015 | Event News
04.09.2015 | Earth Sciences
04.09.2015 | Materials Sciences
04.09.2015 | Life Sciences