Assessing Microbial Stability and Quality of Green Beans Using Various Home Canning Methods

Abstract

Today many consumers follow processing methods recommended either from family members or the internet, which they interpret as being safe. Processing temperature profiles, survival of B. stearothermophilus spores, texture, and color of green beans processed under four home canning methods were assessed. The products were processed using pressure, boiling water bath, steam, or oven canning methods. Pressure canning produced the greatest microbial reductions but this method resulted in the lowest bean quality. The boiling water bath, steam, and oven canning were found to be less safe because the product temperature never achieved 100°C and the resulting microbial counts, >1.7 log CFU/ml, were observed after processing. However, green bean quality was better than pressure canning, with beans from steam canning having the firmest texture and best green color. Although better green bean quality results were observed from internet or family based methods, their safety is questionable considering the high microbial survival.