Project Number: 6645-41420-004-00
Project Type: Appropriated

Start Date: Jul 29, 2004
End Date: Jul 28, 2009

Objective:
Our objectives are to: (1) develop reduced salt fermentation procedures for cucumbers and cabbage that will consistently produce vegetables with firm texture and appropriate flavor; (2) preserve non-fermented cucumbers and peppers in acidified, low-salt, or salt-free solutions so they can be stored and used as process-ready ingredients for food products; (3) develop processing technologies to convert sweetpotatoes into shelf-stable ingredients, such as puree and dehydrated powder, with physical, chemical, and sensory properties suitable for use as ingredients in restructured and formulated food products; (4) increase nutrients and beneficial phytochemicals in sweetpotato products by selection of cultivars with increased concentrations of target components and by optimization of processing conditions to minimize losses; (5) assure removal of acid-tolerant pathogens from acidified vegetable products that cannot tolerate heat processing by prediction and use of appropriate combinations of pH, acid type, and acid concentration.

Approach:
New or improved processing methods will be developed for cucumbers, cabbage, peppers and sweetpotatoes that will increase utilization of these vegetables. Research will be done both to solve problems that limit utilization and to create opportunities to broaden uses for these vegetables as ingredients in formulated foods. Problems to be addressed include excessive generation of processing wastes, loss of quality attributes, and inadequate commercial shelf-life. Opportunities include development of new convenient-to-use ingredient forms for these vegetables and enhancement of the nutrient and beneficial phytochemical levels in products produced from these vegetables. Control of texture is a major quality issue that must be addressed in the development of improved processing methods. Therefore, the basic mechanisms which accelerate and inhibit softening of cucumbers, peppers, and cabbage will be investigated, as well as the factors that modify the rheology of sweetpotato puree. The ability of acid-tolerant microbial pathogens to survive for extended periods of time at low pH is a major concern in the development of new processing techniques. As a result, the mechanisms by which acids kill these pathogens will be determined in order to find improved approaches to assure removal of these organisms in acidified foods. A recent development by this unit of an experimental technique to experimentally separate the effects of hydrogen ions from the effects of protonated acids on killing bacteria will be exploited to further our understanding of the physiology of acid killing.

Project Team

McFeeters, Roger Truong, Van-Den Breidt, Frederick

Related National Programs

Food Safety, (animal and plant products) (108)   Quality and Utilization of Agricultural Products (306)

Related Projects

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