University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Doctoral Thesis:
Dalin Ly
(2020):
SAFETY AND MICROBIAL CHARACTERISTICS OF CAMBODIAN TRADITIONAL FERMENTED FISH AND VEGETABLE FOODS.
Doctoral Thesis - Institut für Lebensmittelwissenschaften,
BOKU-Universität für Bodenkultur,
pp 140.
UB BOKU
obvsg
- Abstract:
- This work deals with the current safety status of fermented vegetable and fish products from Cambodia to improve the safety, quality and acceptability of these foods. In the first part of this thesis, 57 naturally fermented fishery and vegetable products were therefore examined for microbiological parameters and biogenic amines. Although the tested microorganisms were within acceptable ranges, the amounts of histamine and tyramine were higher than the recommended maximum levels in some food samples. Taking into account putrescine and cadaverine next to these two biogenic amines, a high percentage of the fishery samples were of poor hygienic quality. By updating the information on the diversity of microorganisms in fermented foods from the lower Mekong sub region in the second part, the important role of autochthonous lactic acid bacteria (LAB) in various fermented foods in this region was demonstrated. However, to make safe, acceptable and consistent products, controlled fermentation processes using commercial starter cultures are required. In addition to producing standardized, good quality foods, starters should also contribute to improve health. Therefore, in the third section of this work, LAB from Cambodian fermented foods were identified, classified and screened for their ability to produce the bioactive substance gamma-aminobutyric acid. Next to this property, safety is one of essential selection criteria for starters. Starter cultures should, therefore, not possess any transmissible antibiotic resistance gene. Thus, the antimicrobial susceptibility of the identified and characterized LAB strains to different antibiotics was evaluated in the last part of the thesis. Based on the results, strains are selected for further investigation to determine their applicability in food fermentations in Cambodia. Nevertheless, the introduction of food hygienic measures like GMP and HACCP is also needed.
- Betreuer: Domig Konrad
- 1. Berater: Kneifel Wolfgang
- 2. Berater: Mayrhofer Sigrid