TitleGrowth behavior of Alicyclobacillus acidoterrestris as a function of strain and culture conditions
NameMerle, Jennifer M. (author), Montville, Thomas J (chair), Carman, George (internal member), Matthews, Karl R (internal member), Rutgers University, Graduate School - New Brunswick,
DescriptionAlicyclobacillus acidoterrestris is an acidophilic, spore-forming spoilage organism of concern for the fruit juice industry. The occurrence of bacterial spore-formers in low pH foods was thought to be insignificant. However, in recent years, spoilage of acidic juice by Alicyclobacillus was recognized and the seriousness of this situation began to be appreciated. A. acidoterrestris has been associated with commercially pasteurized fruit juices as well as other low pH, shelf-stable products such as bottled tea and isotonic drinks. It has been isolated from garden and forest soils and may be introduced into the manufacturing process through unwashed or poorly washed fruit. If spores are not destroyed by processing, they can germinate, grow, and spoil product. The purpose of this study was to develop an understanding of A. acidoterrestris growth as a function of strain, pH and temperature so that growth of A. acidoterrestris spores might be inhibited by environmental control and product formulation. Four strains of A. acidoterrestris were used to investigate the growth kinetics in response to pH (3.0, 4.0, 5.0) and temperatures (30, 37.5, 45ºC) by measuring the optical density (OD) every hour for 48 hours using a microtitre plate reader to develop the growth curves. The growth rates were calculated using the software program DMFit and were used to illustrate the relationship between the growth kinetics of A. acidoterrestris strains. When examining the generated data, we observed that there were some differences between growth kinetics of tested strains at various pH and temperature conditions. The differences were random and did not follow any specific trend. The use of a reference strain allows for greater availability and reproducibility. Accordingly, the ATCC 49025 strain is representative of the food isolates (strain N1100, N1102 and N1139) and can be used as a reference strain.
NoteIncludes bibliographical references
Noteby Jennifer M. Merle
CollectionGraduate School - New Brunswick Electronic Theses and Dissertations
Organization NameRutgers, The State University of New Jersey
RightsThe author owns the copyright to this work.