Article

Involvement of pectolytic micro‐organisms in coffee fermentation

International Journal of Food Science & Technology (Impact Factor: 1.38). 01/2002; 37(2):191 - 198. DOI: 10.1046/j.1365-2621.2002.00556.x

ABSTRACT

During the fermentation of Coffea arabica L., the most frequently found pectolytic bacteria were Erwinia herbicola and Klebsiella pneumoniae. These micro-organisms produce pectatelyase which is unable to depolymerize esterified pectins of mucilage without previous de-esterification. Furthermore, the optimal activities are observed at pH 8.5 whereas fermentation conditions are acidic (5.3–3.5). The major lactic acid bacteria, Leuconostoc mesenteroides, do not produce pectolytic enzymes. Only a Lactobacillus brevis strain, rarely isolated with a low frequency, shows a polygalacturonase activity compatible with fermentation conditions. Mucilage decomposition seems to be correlated to acidification and not to enzymatic pectolysis. Inoculation with pectolytic micro-organisms allows microbiological control of the fermentation but does not speed up the process. It would be preferable to use lactic acid bacteria so that the pH remained as close as possible to natural fermentation, where acidification is important. This practice would standardize the coffee fermentation microflora and therefore control the end product quality.

Download full-text

Full-text

Available from: Sylvie Avallone
  • Source
    • "Oil yield and stability are improved after enzyme treatment and polyphenol and vitamin E content are increased, improving the oil's organoleptic quality (Kashyap et al. 2001; Hoondal et al. 2002; Iconomou et al. 2010). Pectolytic microorganisms are also used to ferment coffee beans, a process that removes the mucilage layer from the beans (Avallone et al. 2002). For example, a commercial enzyme product containing pectinase is applied to coffee beans to initiate fermentation (Pasha et al. 2013). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Fungi are important natural product sources that have enormous potential for the production of novel compounds for use in pharmacology, agricultural applications and industry. Compared with other natural sources such as plants, fungi are highly diverse but understudied. However, research on Cladosporium cladosporioides revealed the existence of bioactive products such as p-methylbenzoic acid, ergosterol peroxide (EP) and calphostin C as well as enzymes including pectin methylesterase (PME), polygalacturonase (PG) and chlorpyrifos hydrolase. p-Methylbenzoic acid has ability to synthesise 1,5-benzodiazepine and its derivatives, polyethylene terephthalate and eicosapentaenoic acid. EP has anticancer, antiangiogenic, antibacterial, anti-oxidative and immunosuppressive properties. Calphostin C inhibits protein kinase C (PKC) by inactivating both PKC-epsilon and PKC-alpha. In addition, calphostin C stimulates apoptosis in WEHI-231 cells and vascular smooth muscle cells. Based on the stimulation of endoplasmic reticulum stress in some types of cancer, calphostin C has also been evaluated as a potential photodynamic therapeutic agent. Methylesterase (PME) and PG have garnered attention because of their usage in the food processing industry and significant physiological function in plants. Chlorpyrifos, a human, animal and plant toxin, can be degraded and eliminated by chlorpyrifos hydrolase.
    Full-text · Article · Dec 2016
    • "In the literature , only a few studies have been published towards the use of starter cultures for coffee fermentations, although the attempt to control coffee fermentation has existed for over 40 years. A pectolytic yeast (Agate & Bhat, 1966; Avallone et al., 2002) and waste-water of a previous fermentation (Avallone et al., 2002; Butty, 1973; Calle, 1957, 1965) used as inocula were early attempts to utilize starters in coffee fermentations . In more recent studies, Silva et al. (2013) used a multicomponent starter preparation that included pectinolytic yeasts and bacteria. "
    Chapter: Coffee

    No preview · Chapter · Jan 2015
    • "The fruits are then spread over patios or dried mechanically. A large amount of water is used during the pulp removal and in the fermentation tanks (Avallone et al. 2002; Masoud et al. 2004). Semi-dry processing is a variant that combines a wet mechanical process to remove the pulp and a dry process in which the depulped beans are spread in a thin layer on cement patios to allow further aerobic degradation of the mucilage (Vilela et al. 2010). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The coffee fermentation is characterized by the presence of different microorganisms belonging to the groups of bacteria, fungi and yeast. The objectives of this work were to select pectinolytic microorganisms isolated from coffee fermentations and evaluate their performance on coffee pulp culture medium. The yeasts and bacteria isolates were evaluated for their activity of polygalacturonase (PG), pectin lyase (PL) and pectin methylesterase (PME) and metabolites production. Among 127 yeasts isolates and 189 bacterial isolates, 15 were pre-selected based on their ability to produce PL and organic compounds. These isolates were strains identified as Bacillus cereus, Bacillus megaterium, Bacillus subtilis, Candida parapsilosis, Pichia caribbica, Pichia guilliermondii and Saccharomyces cerevisiae. When cultivated in Coffee peel and pulp media in single culture or two by two mixed inocula, different behavior concerning to PME, PL and PG were found. The two principal components PC1 and PC2 accounted for 45.27 and 32.02 % of the total variance. UFLA CN727 and UFLA CN731 strains were grouped in the positive part of PC1 being characterized by 1,2-propanediol, hexanoic acid, decanoic acid, nonanoic acid and ethyl acetate. The UFLA CN448 and UFLA CN724 strains were grouped in the negative part of PC1 and were mainly characterized by guaiacol, butyric acid and citronellol. S. cerevisiae UFLACN727, P. guilliermondii UFLACN731 and C. parapsilosis UFLACN448 isolates are promising candidates to be tested in future studies as coffee starter cultures.
    No preview · Article · Sep 2012 · World Journal of Microbiology and Biotechnology (Formerly MIRCEN Journal of Applied Microbiology and Biotechnology)
Show more