Bulk Preservation of Vegetables Without Fermentation
Pickling Cucumber Improvement Committee Meeting Abstract
R. F. McFeeters
Department of Horticultural Science, North Carolina State University
We are investigating the use of traditional preservatives and vinegar to preserve vegetables salt-free in bulk storage without fermentation. The objective is to maintain the quality of the produce for a reasonable period of time in a process-ready form that does not require desalting or de-acidification.
This approach is intended to minimize generation of a high salt/high BOD waste. Cucumbers have been successfully preserved in 0.6% vinegar, 0.33% calcium chloride, and 450 ppm sodium metabisulfite with the pH lowered to 3.5 using hydrochloric acid. This has been done both in the laboratory and in 200-300-gallon bag-in-box storage. Prior to final processing, food-grade hydrogen peroxide is mixed in the cover solution and held for 48 hr to remove the sulfite from cucumbers. More recently, we have begun laboratory experiments on a similar preservation approach for red bell peppers. We have found that peppers can be preserved with 0.9% vinegar, 0.11% calcium chloride, 100 ppm sulfite, 0.04% Na benzote, and hydrochloric acid sufficient to lower the pH to 3.5.
The firmness of red peppers is more difficult to maintain a reasonable level than is the firmness of cucumbers. Therefore, it is necessary to blanch red peppers before storage. Sulfite has been found to extend the storage period during which peppers maintain acceptable firmness.
For further information, contact:
- Dr. R. F. McFeeters
- USDA-ARS, Department of Food Science
- North Carolina State University, Raleigh, NC 27695-7624
- Telephone: 919-515-2979; Fax: 919-856-4361
- E-mail: rfm@unity.ncsu.edu