Back
A lab-scale model system for cocoa bean fermentation.
Journal article

A lab-scale model system for cocoa bean fermentation.

  • Romanens E Centre for Microbiology, Institute of Food and Beverage Innovation, Zurich University of Applied Sciences, Einsiedlerstrasse 31, 8820, Wadenswil, Switzerland.
  • Näf R Centre for Microbiology, Institute of Food and Beverage Innovation, Zurich University of Applied Sciences, Einsiedlerstrasse 31, 8820, Wadenswil, Switzerland.
  • Lobmaier T Centre for Microbiology, Institute of Food and Beverage Innovation, Zurich University of Applied Sciences, Einsiedlerstrasse 31, 8820, Wadenswil, Switzerland.
  • Pedan V Centre for Ingredients, Institute of Food and Beverage Innovation, Zurich University of Applied Science, Grüentalstrasse 14, 8820, Wadenswil, Switzerland.
  • Leischtfeld SF Centre for Microbiology, Institute of Food and Beverage Innovation, Zurich University of Applied Sciences, Einsiedlerstrasse 31, 8820, Wadenswil, Switzerland.
  • Meile L Laboratory of Food Biotechnology, Institute of Food, Nutrition and Health, Schmelzbergstrasse 7, ETH, 8092, Zurich, Switzerland.
  • Schwenninger SM Centre for Microbiology, Institute of Food and Beverage Innovation, Zurich University of Applied Sciences, Einsiedlerstrasse 31, 8820, Wadenswil, Switzerland. susanne.miescher-schwenninger@zhaw.ch.
Show more…
  • 2018-03-02
Published in:
  • Applied microbiology and biotechnology. - 2018
Acetic acid bacteria
Cocoa bean drying
Cocoa bean fermentation
Lab-scale fermentation
Lactic acid bacteria
Yeast
Acetic Acid
Bacteria
Bioreactors
Cacao
Fermentation
Food Microbiology
Fungi
Seeds
English Lab-scale systems modelling the spontaneous cocoa bean fermentation process are useful tools to research the influence of process parameters on the fermentation and the final bean quality. In this study in Honduras, a 1-kg lab-scale fermentation (LS-F) was compared to a 300-kg on-farm fermentation (OF-F) in a multiphasic approach, analysing microbial counts, microbial species diversity, physico-chemical parameters, and final dried bean quality. Yeast and total aerobic counts of up to 8 log CFU/g during the LS-F were comparable to the OF-F, while counts for lactic acid bacteria and acetic acid bacteria were up to 3 log CFU/g lower during the LS-F than during the OF-F. While species of the genera Hansenia, Saccharomyces, and Acetobacter dominated most of the fermentation processes, the genera dominating the drying phases were Pichia, Trichosporon, Pediococcus, and Acetobacter. Dried beans resulting from the LS-F, compared to the OF-F, were similar in contents of acetic acid, 6 times lower in lactic acid, up to 4 times higher in residual sugars, and 3-12 times higher in polyphenols. Dried beans processed at LS showed a similar flavour profile in terms of astringency, bitterness, acidity, and brown, fine, and cocoa flavours, but 2 units higher off-flavours than OF processed beans. With 81%, the share of well-fermented beans from the LS-F complied with industrial standards, whereas 7% over-fermented beans were above the threshold. Conclusively, the 5-day model fermentation and subsequent drying successfully mimicked the on-farm process, providing a high-throughput method to screen microbial strains to be used as starter cultures.
Language
  • English
Open access status
closed
Identifiers
Persistent URL
https://sonar.ch/global/documents/277328
Statistics
Document views: 45 File downloads: