Development and analysis of mathematical methods to evaluate the effects of high hydrostatic pressure sublethal treatment in Listeria monocytogenes cultures
Tutor/a - Director/a
Bover Cid, Sara
Estudiant
Weihong, Ye
Tipus de document
Treball Final de Grau
Data
2012
rights
Accés obert
Editorial
Universitat Politècnica de Catalunya
UPCommons
Resum
Every year there are millions of cases of diseases caused by food pathogens. Therefore,
food safety is one of the most important challenges in the food industry. One of the
most important pathogens is Listeria monocytogenes, due to the high mortality and its
high resistance against conventional methods of conservation.
High hydrostatic pressure (HHP) treatment is an efficient method with good prospects
of implementation in the food industry. In this project, the effects of HHP sublethal
treatment on cultures of different strains of Listeria monocytogenes were analysed
through mathematical methods. The experimental data used in this project were
obtained mainly by Bioscreen. The experimental work was performed in the
installations of IRTA, at Monells.
Particularly, an innovative methodology was developed, which consists of the
calibration of data obtained through absorbance (optical density) with data obtained
from plate cultures (CFU). In order to study the effect of an HHP treatment, the
goodness of the three analysis methods were evaluated: (1) using direct data of optical
density, (2) 2-fold dilution method and (3) CFU obtained from calibration with optical
density. The advantages and drawbacks of each method were analyzed. This study
shows the interest to keep working on the improvement of the method based on the
calibration of data obtained from optical density.
Professorat participant
- Bover Cid, Sara