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Fulltext Detailed analysis of the microbial population in Malaysian spontaneous cocoa pulp fermentations reveals a core and variable microbiota

Meersman E, Steensels J, Mathawan M, Wittocx PJ, Saels V, Struyf N, et al.

PLoS One, 2013;8(12):e81559.
PMID: 24358116 DOI: 10.1371/journal.pone.0081559

The fermentation of cocoa pulp is one of the few remaining large-scale spontaneous microbial processes in today's food industry. The microbiota involved in cocoa pulp fermentations is complex and variable, which leads to inconsistent production efficiency and cocoa quality. Despite intensive research in the field, a detailed and comprehensive analysis of the microbiota is still lacking, especially for the expanding Asian production region. Here, we report a large-scale, comprehensive analysis of four spontaneous Malaysian cocoa pulp fermentations across two time points in the harvest season and two fermentation methods. Our results show that the cocoa microbiota consists of a "core" and a "variable" part. The bacterial populations show a remarkable consistency, with only two dominant species, Lactobacillus fermentum and Acetobacter pasteurianus. The fungal diversity is much larger, with four dominant species occurring in all fermentations ("core" yeasts), and a large number of yeasts that only occur in lower numbers and specific fermentations ("variable" yeasts). Despite this diversity, a clear pattern emerges, with early dominance of apiculate yeasts and late dominance of Saccharomyces cerevisiae. Our results provide new insights into the microbial diversity in Malaysian cocoa pulp fermentations and pave the way for the selection of starter cultures to increase efficiency and consistency.

Matched MeSH terms: Cacao/microbiology*
Effects of encapsulation on the viability of potential probiotic Lactobacillus plantarum exposed to high acidity condition and presence of bile salts

Tee WF, Nazaruddin R, Tan YN, Ayob MK

Food Sci Technol Int, 2014 Sep;20(6):399-404.
PMID: 23774606 DOI: 10.1177/1082013213488775

This study investigated the survival of encapsulated potential probiotic Lactobacillus plantarum which isolated from fermented cocoa beans. κ-Carrageenan was used to encapsulate the probiotic. Encapsulation techniques such as emulsification, freeze-drying or extrusion were adopted to encapsulate the probiotic. Freeze-drying and extrusion methods showed higher (p

Matched MeSH terms: Cacao/microbiology
Optimization of Culture Medium for the Growth of Candida sp. and Blastobotrys sp. as Starter Culture in Fermentation of Cocoa Beans (Theobroma cacao) Using Response Surface Methodology (RSM)

Mahazar NH, Zakuan Z, Norhayati H, MeorHussin AS, Rukayadi Y

Pak J Biol Sci, 2017;20(3):154-159.
PMID: 29023007 DOI: 10.3923/pjbs.2017.154.159

BACKGROUND AND OBJECTIVE: Inoculation of starter culture in cocoa bean fermentation produces consistent, predictable and high quality of fermented cocoa beans. It is important to produce healthy inoculum in cocoa bean fermentation for better fermented products. Inoculum could minimize the length of the lag phase in fermentation. The purpose of this study was to optimize the component of culture medium for the maximum cultivation of Candida sp. and Blastobotrys sp.
MATERIALS AND METHODS: Molasses and yeast extract were chosen as medium composition and Response Surface Methodology (RSM) was then employed to optimize the molasses and yeast extract.
RESULTS: Maximum growth of Candida sp. (7.63 log CFU mL-1) and Blastobotrys sp. (8.30 log CFU mL-1) were obtained from the fermentation. Optimum culture media for the growth of Candida sp., consist of 10% (w/v) molasses and 2% (w/v) yeast extract, while for Blastobotrys sp., were 1.94% (w/v) molasses and 2% (w/v) yeast extract.
CONCLUSION: This study shows that culture medium consists of molasses and yeast extract were able to produce maximum growth of Candida sp. and Blastobotrys sp., as a starter culture for cocoa bean fermentation.

Matched MeSH terms: Cacao/microbiology*
Characterization of strains of Weissella fabalis sp. nov. and Fructobacillus tropaeoli from spontaneous cocoa bean fermentations

Snauwaert I, Papalexandratou Z, De Vuyst L, Vandamme P

Int J Syst Evol Microbiol, 2013 May;63(Pt 5):1709-1716.
PMID: 22922535 DOI: 10.1099/ijs.0.040311-0

Six facultatively anaerobic, non-motile lactic acid bacteria were isolated from spontaneous cocoa bean fermentations carried out in Brazil, Ecuador and Malaysia. Phylogenetic analysis revealed that one of these strains, designated M75(T), isolated from a Brazilian cocoa bean fermentation, had the highest 16S rRNA gene sequence similarity towards Weissella fabaria LMG 24289(T) (97.7%), W. ghanensis LMG 24286(T) (93.3%) and W. beninensis LMG 25373(T) (93.4%). The remaining lactic acid bacteria isolates, represented by strain M622, showed the highest 16S rRNA gene sequence similarity towards the type strain of Fructobacillus tropaeoli (99.9%), a recently described species isolated from a flower in South Africa. pheS gene sequence analysis indicated that the former strain represented a novel species, whereas pheS, rpoA and atpA gene sequence analysis indicated that the remaining five strains belonged to F. tropaeoli; these results were confirmed by DNA-DNA hybridization experiments towards their respective nearest phylogenetic neighbours. Additionally, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry proved successful for the identification of species of the genera Weissella and Fructobacillus and for the recognition of the novel species. We propose to classify strain M75(T) ( = LMG 26217(T) = CCUG 61472(T)) as the type strain of the novel species Weissella fabalis sp. nov.

Matched MeSH terms: Cacao/microbiology*
Fulltext Assessment of the yeast species composition of cocoa bean fermentations in different cocoa-producing regions using denaturing gradient gel electrophoresis

Papalexandratou Z, De Vuyst L

FEMS Yeast Res., 2011 Nov;11(7):564-74.
PMID: 22093683 DOI: 10.1111/j.1567-1364.2011.00747.x

The yeast species composition of 12 cocoa bean fermentations carried out in Brazil, Ecuador, Ivory Coast and Malaysia was investigated culture-independently. Denaturing gradient gel electrophoresis of 26S rRNA gene fragments, obtained through polymerase chain reaction with universal eukaryotic primers, was carried out with two different commercial apparatus (the DCode and CBS systems). In general, this molecular method allowed a rapid monitoring of the yeast species prevailing during fermentation. Under similar and optimal denaturing gradient gel electrophoresis conditions, the CBS system allowed a better separated band pattern than the DCode system and an unambiguous detection of the prevailing species present in the fermentation samples. The most frequent yeast species were Hanseniaspora sp., followed by Pichia kudriavzevii and Saccharomyces cerevisiae, independent of the origin of the cocoa. This indicates a restricted yeast species composition of the cocoa bean fermentation process. Exceptionally, the Ivorian cocoa bean box fermentation samples showed a wider yeast species composition, with Hyphopichia burtonii and Meyerozyma caribbica among the main representatives. Yeasts were not detected in the samples when the temperature inside the fermenting cocoa pulp-bean mass reached values higher than 45 °C or under early acetic acid production conditions.

Matched MeSH terms: Cacao/microbiology*