Featured Research

from universities, journals, and other organizations

Market lighting affects nutrients in salad greens, researchers find

Date:
May 4, 2011
Source:
USDA/Agricultural Research Service
Summary:
Many people reach toward the back of the fresh-produce shelf to find the freshest salad greens with the latest expiration dates. But a new study by agriculture scientists may prompt consumers to instead look for packages that receive the greatest exposure to light -- usually those found closest to the front.

ARS researchers have found that spinach leaves exposed to light similar to the 24-hour fluorescent light received by packages of fresh salad greens on display in grocery stores had higher levels of some nutrients than did leaves exposed to continuous dark.
Credit: Photo by Keith Weller

Many people reach toward the back of the fresh-produce shelf to find the freshest salad greens with the latest expiration dates. But a study led by U.S. Department of Agriculture (USDA) scientists may prompt consumers to instead look for packages that receive the greatest exposure to light--usually those found closest to the front.

The study was led by postharvest plant physiologist Gene Lester while at the Agricultural Research Service (ARS) Crop Quality and Fruit Insects Research Unit in Weslaco, Texas. ARS is USDA's chief intramural scientific research agency.

Lester and colleagues Donald Makus and Mark Hodges found that spinach leaves exposed to continuous light during storage were, overall, more nutritionally dense than leaves exposed to continuous dark. Lester now works at the ARS Food Quality Laboratory in Beltsville, Md.

For the study, the researchers exposed spinach leaves to light similar to the 24-hour artificial fluorescent light received by spinach in packages located at the front of the display case. A second group was enclosed in two-layer-thick, brown-grocery-bag paper to represent the "dark treatment."

Both experimental groups were housed in market-type, light-transmissible polymer tubs with snap-tight lids and were kept in walk-in storage chambers at 4 degrees Celsius, the same temperature at which markets currently display packaged spinach. The light reaction of photosynthesis is not temperature-dependent and can occur at 4 degrees C in the right type of light.

The researchers found that the continuous light affected the leaves' photosynthetic system-resulting in a significant increase in levels of carotenoids and vitamins C, E, K, and B9, or folate.

While the simulated retail light conditions actually helped the stored leaves gain in content of several human-healthy vitamins, some wilting occurred after three days of storage in flat-leaf spinach, but not crinkled-leaf types.

Results from this work were published in the Journal of Agricultural and Food Chemistry.


Story Source:

The above story is based on materials provided by USDA/Agricultural Research Service. The original article was written by Rosalie Marion Bliss. Note: Materials may be edited for content and length.


Journal Reference:

  1. Gene E. Lester, Donald J. Makus, D. Mark Hodges. Relationship between Fresh-Packaged Spinach Leaves Exposed to Continuous Light or Dark and Bioactive Contents: Effects of Cultivar, Leaf Size, and Storage Duration. Journal of Agricultural and Food Chemistry, 2010; 58 (5): 2980 DOI: 10.1021/jf903596v

Cite This Page:

USDA/Agricultural Research Service. "Market lighting affects nutrients in salad greens, researchers find." ScienceDaily. ScienceDaily, 4 May 2011. <www.sciencedaily.com/releases/2011/05/110503133054.htm>.
USDA/Agricultural Research Service. (2011, May 4). Market lighting affects nutrients in salad greens, researchers find. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2011/05/110503133054.htm
USDA/Agricultural Research Service. "Market lighting affects nutrients in salad greens, researchers find." ScienceDaily. www.sciencedaily.com/releases/2011/05/110503133054.htm (accessed July 31, 2014).

Share This




More Plants & Animals News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Visitors Feel Part of the Pack at Wolf Preserve

Visitors Feel Part of the Pack at Wolf Preserve

AP (July 31, 2014) Seacrest Wolf Preserve on the northern Florida panhandle allows more than 10,000 visitors each year to get up close and personal with Arctic and British Columbian Wolves. (July 31) Video provided by AP
Powered by NewsLook.com
Florida Panther Rebound Upsets Ranchers

Florida Panther Rebound Upsets Ranchers

AP (July 31, 2014) With Florida's panther population rebounding, some ranchers complain the protected predators are once again killing their calves. (July 31) Video provided by AP
Powered by NewsLook.com
Dangerous Bacteria Kills One in Florida

Dangerous Bacteria Kills One in Florida

AP (July 31, 2014) Sarasota County, Florida health officials have issued a warning against eating raw oysters and exposing open wounds to coastal and inland waters after a dangerous bacteria killed one person and made another sick. (July 31) Video provided by AP
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins