Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Grape news: New treatment combination safe alternative to sulfur dioxide

16.04.2010
Hot water, rachis removal, modified atmosphere packaging combination preserves table grapes

Packaged fresh-cut grapes are becoming increasingly popular with consumers who like the convenience and health benefits of these ready-to-eat fruits.

To keep table grapes fresh and increase shelf life, scientists are seeking advanced techniques that provide healthy, safe alternatives to conventional packing methods.

Researchers from the U.S. Department of Agriculture's Agricultural Research Service (USDA ARS) have developed and tested an effective new technique that combines hot water treatment, rachis removal, and modified atmosphere packaging (MA) to extend the shelf life of table grapes.

Commercially packaged table grapes stored in clusters in perforated packaging have a short shelf life—typically 8 to 10 weeks—as a result of their exposure to the environment. Grape shelf life is often shortened by factors including fruit weight loss, stem browning, softening, shattering, and decay. Because of its effectiveness in delaying stem browning and decay, sulfur dioxide gas (SO2) is currently the treatment of choice in many countries for prolonging shelf life of grapes. There are disadvantages to sulfur dioxide use, however. The concentration of SO2 necessary to inhibit fungal growth may induce injuries in grape fruits and stems, and sulfite residues pose a health risk for some individuals. Applications of SO2 have been restricted in many countries, making it essential to identify safe, alternative technologies that effectively control fungal growth and assure high-quality fruit.

Yaguang Luo and William Conway from the USDS ARS, in collaboration with Liping Kou, Wu Ding, and Xinghua Liu from China's Northwest A&F University, recently published a report in HortScience that explored alternatives to sulfur dioxide for maintaining quality of table grapes, including various combinations of rachis removal, chlorinated wash, hot water treatment, and modified atmosphere packaging.

Grapes were prepared by cutting off the rachis 1 to 2 mm from the fruit or by keeping the clusters intact. After initial preparation, short-stem and cluster grapes were subjected to chlorinated wash and/or hot water (45ºC for 8 minutes) treatment and packaged in plastic trays sealed with a gas-permeable film. The treated grapes, as well as the commercially packed grapes in their original packages, were stored at 5ºC for up to 4 weeks.

According to the Kou, a visiting scientist from China and the study's lead researcher, the hot water treatment resulted in significantly higher oxygen retention and lower carbon dioxide accumulation in packages, firmer texture, higher overall visual quality, lower decay rate, and lower microbial populations than other treatments or commercially packed grapes. Grapes that were cut from the rachis and treated with hot water and chlorine maintained the highest quality for 4 weeks, with the least decay among all treatments. A chlorine prewash treatment significantly reduced microbial populations on cluster grapes and maintained better overall quality.

Kou concluded that "the combination of these treatments maintained excellent visual quality throughout the entire storage duration, whereas the commercially packaged grapes became decayed and their quality declined to a level that was unacceptable. The combination treatment was successful in reducing spoilage microbes, preventing dehydration, and delaying softening and senescence of grapes."

The complete study and abstract are available on the ASHS HortScience electronic journal web site: http://hortsci.ashspublications.org/cgi/content/abstract/44/7/1947

Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application. More information at ashs.org

Michael W. Neff | EurekAlert!
Further information:
http://www.ashs.org

More articles from Agricultural and Forestry Science:

nachricht Plasma-zapping process could yield trans fat-free soybean oil product
02.12.2016 | Purdue University

nachricht New findings about the deformed wing virus, a major factor in honey bee colony mortality
11.11.2016 | Veterinärmedizinische Universität Wien

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Water - as the underlying driver of the Earth’s carbon cycle

17.01.2017 | Earth Sciences

Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

17.01.2017 | Materials Sciences

Smart homes will “LISTEN” to your voice

17.01.2017 | Architecture and Construction

VideoLinks
B2B-VideoLinks
More VideoLinks >>>