scholarly journals Filamentous fungi diversity in the natural fermentation of Amazonian cocoa beans and the microbial enzyme activities

2019 ◽  
Vol 69 (9) ◽  
pp. 975-987 ◽  
Author(s):  
Jean Aquino de Araújo ◽  
Nelson Rosa Ferreira ◽  
Silvia Helena Marques da Silva ◽  
Guilherme Oliveira ◽  
Ruan Campos Monteiro ◽  
...  
Author(s):  
G.P. Ganda-Putra ◽  
L.P. Wrasiati ◽  
N.M. Wartini

Pulp degradation during cocoa fermentation can be carried out by depolymerization process of pulp pectin using endogenous pectolytic enzymes at optimum condition. The objectives of this research were to study the effect of fermentation process based on optimum condition in terms of temperature and pH of pulp pectin depolymerization using endogenous pectolytic enzymes polygalakturonase (PG) and pectin metyl esterase (PME) and fermentation period in cocoa processing on quality characteristics of cocoa beans produced and to study the role of those fermentation process in reducing fermentation time to produce cocoa beans with standard quality. This research used split plot design, with treatments of process condition of cocoa fermentation as main plot and fermentation period as split plot. Treatment of process condition of cocoa fermentation consisted of optimum condition for pulp pectin depolymerization by PGs (temperature 47.5OC; initial pulp pH 4.6); optimum condition of depolymerization on sequence depolymerization by PGs (temperature 48.5OC; initial pulp pH 8.0 during 1 day; last temperature 47.5OC; initial pulp pH 4.6 during 6 days), and natural fermentation process a control. While treatment of fermentation period consisted of 0, 1, 2, 3, 4, 5, 6 and 7 days. Evaluation of fermentation period was carried out based on pursuant to criteria of unfermented beans content and fermentation index. The results showed that process condition and fermentation time of cocoa affected quality characteristic of cocoa beans produced. Period of cocoa fermentation process based on optimum condition for pulp pectin depolymerization using endogenous pectolytic enzymes was 2 days shorter compared to natural fermentation. Cocoa beans quality of grade I and II were obtained from fermentation time of 4 and 2 days, respectively, using fermentation process based on optimum condition of pulp pectin depolymerization using endogenous pectolytic enzymes, whereas 6 and 4 days, respectively, when using natural fermentation.Key words: cocoa quality, fermentation, depolymerization, pectolytic.


2021 ◽  
pp. 351-373
Author(s):  
Dixita Chettri ◽  
Bhaskar Sharma ◽  
Ashwani Kumar Verma ◽  
Anil Kumar Verma

Author(s):  
D Q Wang ◽  
G D Chai ◽  
J Q Shan ◽  
Z J Yang ◽  
H E Li ◽  
...  

1988 ◽  
Vol 60 (2) ◽  
pp. 287-296 ◽  
Author(s):  
H. P. S. Makkar ◽  
B. Singh ◽  
R. K. Dawra

1. The objective of the present experiment was to study the effects of oak (Quercus incana) leaves rich in tannins on various enzyme activities of the bovine rumen.2. The procedure employed was incubation of tannin-rich, very-low-tannin or virtually tannin-free leaves in nylon-gauze bags in the rumen, and determination of enzyme activities in microbes tightly bound to the solid matrix and in microbes loosely plus tightly attached to the solid matrix.3. The activities of urease (EC3.5.1.5), carboxymethylcellulase, glutamate dehydrogenase (EC1.4.1.2) and alanine aminotransferase (glutamic-pyruvic transaminase) (EC2.6.1.2) were significantly lower in the tannin-rich group, whereas the activities of glutamate ammonia ligase (glutamine synthetase) (EC6.3.1.2; both yγ- glutamyltransferase (EC2.3.2.2) and the forward reaction) were higher in the tannin-rich group. These changes were more marked in micro-organisms tightly bound to the solid matrix than in the more complex microbial compartment.4. The protein, DNA and RNA contents, and protein: RNA ratio, were significantly lower in the tannin-rich group, whereas no difference was observed for protein: DNA between the groups.5. Effects of tannin-containing extracts of oak leaves on various rumen enzymes in vitro showed a trend similar to that observed in nylon-gauze bags, suggesting that the changes observed in various compartments were due to the tannins of oak leaves.


Author(s):  
Carl E Hansen ◽  
Margarita del Olmo ◽  
Christine Burri

2004 ◽  
Vol 30 (1) ◽  
pp. 301-304
Author(s):  
Xiaobo TANG ◽  
Yoshinari YAMADERA ◽  
Toshitaka MIYAZAKI

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