Low Water Activity Packaged White Bread.
Abstract
The purpose of this study was to develop a shelf-stable packaged white pan bread for military use. Shelf life of bread may be extended to several months by proper control of water activity, pH, packaging conditions, and by addition of antimicrobial compounds and dough conditioners. Water activity of bread was effectively lowered from 0.97 to 0.92-0.93 by addition of 7% sorbitol, 1% propylene glycol and 2% glycerol (flour basis). Incorporation of 0.3% lactic acid powder to the bread reduced its pH to 5.0. Other formulation changes included 10% shortening and addition of sodium stearoyl-2-lactylate (antistaling). The resulting humectant bread was satisfactory for baking and sensory quality. To prevent dehydration and to exclude oxygen, the bread was packaged in a partial C02 atmosphere in a retort pouch. The packaged humectant bread was microbiologically stable up to about four months. Growth of Aspergillus flavus, Staphlococcus aureus and other aerobic organisms were inhibited. However, pH of the product should be lowered to 4.8 to guard against anaerobic organisms. Storage of the humectant bread resulted in a number of undesirable changes: increases in browning, firmness, dryness, crumbliness, rancid flavor and aroma, and decreases in pH and overall preference. Further improvement will be needed to extend the shelf-life of the bread to one year at 30 C. Based on this study, a maximum a sub w of 0.92-0.93 and a maximum pH of 4.8 are recommended for the humectant bread. Partial CO2 packaging using a retort pouch or metal can is preferred for maximum stability.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 31, 1985
- Accession Number
- ADA193484
Entities
People
- Charles W. Nagel
- Debbie Hsu
- Gordon G. Rubenthaler
- Henry K. Leung
- Nancy Larson-powers
Organizations
- Washington State University