Navigation Links
Illinois scientists put cancer-fighting power back into frozen broccoli
Date:8/6/2013

URBANA, Ill. There was bad news, then good news from University of Illinois broccoli researchers this month. In the first study, they learned that frozen broccoli lacks the ability to form sulforaphane, the cancer-fighting phytochemical in fresh broccoli. But a second study demonstrated how the food industry can act to restore the frozen vegetable's health benefits.

"We discovered a technique that companies can use to make frozen broccoli as nutritious as fresh. That matters because many people choose frozen veggies for their convenience and because they're less expensive," said Elizabeth Jeffery, a U of I professor of nutrition.

"Whenever I've told people that frozen broccoli may not be as nutritious as fresh broccoli, they look so downcast," she added.

As little as three to five servings of broccoli a week provides a cancer-protective benefit, but that isn't true for bags of broccoli that you pluck out of your grocery's freezer, she noted.

The problem begins when soon-to-be-frozen broccoli is blanched, or heated to high temperatures, to inactivate enzymes that can cause off-colors, tastes, and aromas during the product's 18-month shelf life, she explained.

The extreme heat destroys the enzyme myrosinase, which is necessary to form sulforaphane, the powerful cancer-preventive compound in broccoli, she said.

"We know this important enzyme is gone because in our first study we tested three commercially frozen broccoli samples before and after cooking. There was very little potential to form sulforaphane before the frozen broccoli was cooked and essentially none after it was cooked as recommended," said Edward B. Dosz, a graduate student in Jeffery's laboratory.

In the second study, the researchers experimented with blanching broccoli at slightly lower temperatures instead of at 86C, the current industry standard. When they used a temperature of 76C, 82 percent of the enzyme myrosinase was preserved without compromising food safety and quality.

Sulforaphane is formed when fresh broccoli is chopped or chewed, bringing its precursor glucoraphanin and the enzyme myrosinase into contact with each other. The researchers first thought that thawing frozen broccoli in the refrigerator might rupture the plant's cells and kick-start the enzymesubstrate interaction. It didn't work, Dosz said.

But they had previously had success using other food sources of myrosinase to boost broccoli's health benefits. So the researchers decided to expose frozen broccoli to myrosinase from a related cruciferous vegetable.

When they sprinkled 0.25 percent of daikon radishan amount that's invisible to the eye and undetectable to our taste budson the frozen broccoli, the two compounds worked together to form sulforaphane, Dosz said.

"That means that companies can blanch and freeze broccoli, sprinkle it with a minute amount of radish, and sell a product that has the cancer-fighting component that it lacked before," he said.

One question remained: Would sulforaphane survive the heat of microwave cooking? "We were delighted to find that the radish enzyme was heat stable enough to preserve broccoli's health benefits even when it was cooked for 10 minutes at 120F. So you can cook frozen broccoli in the microwave and it will retain its cancer-fighting capabilities," Dosz said.

Jeffery hopes that food processors will be eager to adopt this process so they can market frozen broccoli that has all of its original nutritional punch.

Until they do, she said that consumers can spice up their frozen, cooked broccoli with another food that contains myrosinase to bring the cancer-fighting super-food up to nutritional speed.

"Try teaming frozen broccoli with raw radishes, cabbage, arugula, watercress, horseradish, spicy mustard, or wasabi to give those bioactive compounds a boost," she advised.


'/>"/>

Contact: Phyllis Picklesimer
p-pickle@illinois.edu
217-244-2827
University of Illinois College of Agricultural, Consumer and Environmental Sciences
Source:Eurekalert

Related biology news :

1. University of Illinois researchers develop AFM-IR for nanometer scale chemical identification
2. Illinois town provides a historical foundation for todays bee research
3. University of Illinois receives grant to study ozone resistance in corn
4. University of Illinois to improve crop yield through photosynthesis in a new global effort
5. University of Illinois at Urbana-Champaign awarded 5-year grant from NASA
6. University of Illinois professor develops tool that helps dietitians deliver info clients need and can understand
7. Scientists learn how soy foods protect against colon cancer
8. Wistar scientists decipher structure of NatA, an enzyme complex that modifies most human proteins
9. Scientists uncover secrets of starfishs bizarre feeding mechanism
10. Geoscientists unearth mineral-making secrets potentially useful for new technologies
11. Scientists discover a molecular switch in cancers of the testis and ovary
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/1/2016)... MELBOURNE, Fla. , Feb. 1, 2016  Wocket® smart wallet ( ... actor and television personality, Joey Fatone . Las ... and greet fans. --> Las Vegas , ... --> The new video ad was filmed at the ... Joey appeared at the Wocket booth to meet and greet fans. ...
(Date:1/25/2016)... 2016   Unisys Corporation (NYSE: UIS ) today ... (JFK) International Airport, New York City , to ... attempting to enter the United States using ... pilot testing of the system at Dulles last year. ... JFK during January 2016. --> pilot testing of ...
(Date:1/22/2016)... http://www.researchandmarkets.com/research/p74whf/global_biometrics ) ... "Global Biometrics Market in Retail Sector 2016-2020" ... --> http://www.researchandmarkets.com/research/p74whf/global_biometrics ) has announced the ... in Retail Sector 2016-2020" report to ... and Markets ( http://www.researchandmarkets.com/research/p74whf/global_biometrics ) has announced ...
Breaking Biology News(10 mins):
(Date:2/4/2016)... New FDA action date of July 22, ... July 22, 2016   --> - ... - Lifitegrast has the potential to be the only ... signs and symptoms of dry eye disease in adults --> ... approved in the U.S. in the past decade indicated for the treatment of ...
(Date:2/4/2016)... Church, VA (PRWEB) , ... ... ... first-year cybersecurity conference presented by Bloomsburg University’s Digital Forensics Club, takes place ... PA. The two-day event features 20+ speakers and activities such as workshops ...
(Date:2/4/2016)... VANCOUVER, British Columbia and MENLO PARK, ... Inc. (OTCQX: DMPI) ("DelMar" and the "Company"), a biopharmaceutical ... therapies, today announced that it will present at the ... on Monday, February 8, 2016 at 10:00 a.m. EST in ... Jeffrey Bacha , DelMar,s president and CEO, will provide an ...
(Date:2/4/2016)... , Feb. 4, 2016  Spherix Incorporated (Nasdaq: ... the fostering and monetization of intellectual property, today provided ... Uniden in the Northern District of Texas ... forward.  Inter Partes Re-examination ("IPR") ... Patent Office.  The IPR was initiated on only certain ...
Breaking Biology Technology: