Application of intense pulsed light for surface sterilization and food quality improvement

Flashblast™ (a registered trademark) is an intense broad spectrum pulsed light source developed by Maxwell Laboratories, San Diego, California which utilizes a Xenon flashlamp for emitting a mixed spectrum of ultraviolet, visible and infrared light. The project's objective was to determine the feasibility of ultra-high intensity light for improving food quality by reducing surface microbial contamination and selected mold metabolites (aflatoxins). Flashblast™ light was found to be highly effective in inactivating vegetative cells of E. coli, S. aureus, B. cereus and B. subtilis. Bacilli and A. niger spores were also susceptible to Flashblast light at somewhat higher fluences. Ultrastructural study with the scanning and transmission electron microscopes indicated that Flashblast™ treated gram-negative E. coli population is more susceptible to membrane damage when compared to other microorganisms. This suggests that photoinactivation involves effects on sensitive sites (genetic material) within the treated organisms which do not lead to significant changes in the microorganism morphology. Food acceptability studies on cheese, bread, strawberries and turkey breasts did not show a significant alteration in color, flavor and texture (p≤0.05). The results obtained with bread and strawberries showed commercial feasibility with an approximate 50% shelf-life extension. Flashblast™ treatment caused photodegradation of most aflatoxin types when multiple flash sequences were employed. It was concluded that full spectrum Flashblast™ light is highly effective for the inactivation of microorganisms and destruction of aflatoxins without causing undesirable sensory changes in foods.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Food Science and Technology

Department dc:contributor.department

Food Science and Technology

Grantor dc:publisher

Virginia Polytechnic Institute and State University

Year dc:date.issued

1988

Author dc:creator

• Avashia, Sanjiv H.

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10919/80167

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/80167