“The only land suitable for supplying this abundance of year-round, high quality, fresh leafy vegetables, which are eaten raw by large populations in Europe and the United States, is in special geographic regions, with ideal soil and climate conditions”, says Robert Mandrell from the US Department of Agriculture’s Research Service in Albany, California.
This move to the year-round supply of leafy vegetables has required new methods to clean, package and deliver rapidly these fragile food items across large distances to consumers in many parts of the world. These include harvesting mowers for some leafy greens, processing in water flumes and triple washing, and modified atmosphere packaging for extended shelf-life.
Recent food scares and food poisoning outbreaks have led to intensive investigations of farms and ranches. These have shown that at least some food poisoning bacteria outbreaks have been due to field contamination before the greens are even harvested.
“This situation complicates strategies for eliminating illnesses and outbreaks due to the complex ecosystem of multiple potential sources, such as water, wildlife, and nearby livestock, all of which could be sources of bacteria causing food poisoning”, says Robert Mandrell.
Following wide media coverage of outbreaks caused by E. coli in leafy vegetables and Salmonella in tomatoes, the US fresh produce industry and federal and state agencies are trying to address the microbial food safety of leafy greens and other vegetables. Major US produce industry associations have worked together to establish a marketing agreement, a set of food safety guidelines (metrics) for growers to produce and harvest leafy greens, and have increased funding for research.
Probably, a convergence of unusual events is required for very large outbreaks to occur, a factor everyone is hoping will not affect 2007 harvests. Logical theories about pre-harvest contamination provide points for study, but no definitive conclusions about the most recent outbreaks can be provided. Fresh, minimally processed leafy greens are here to stay, if the industry continues to work hard to re-establish consumer confidence.
Lucy Goodchild | alfa
The secret sulfate code that lets the bad Tau in
16.07.2018 | American Society for Biochemistry and Molecular Biology
Colorectal cancer risk factors decrypted
13.07.2018 | Max-Planck-Institut für Stoffwechselforschung
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
13.07.2018 | Event News
13.07.2018 | Materials Sciences
13.07.2018 | Life Sciences