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Eric Odoux - One of the best experts on this subject based on the ideXlab platform.
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New insight on the genesis and fate of odor-active compounds in Vanilla Beans (Vanilla planifolia G. Jackson) during traditional curing
Food Research International, 2011Co-Authors: Araceli Pérez Silva, Ziya Gunata, Jean Paul Lepoutre, Eric OdouxAbstract:Green Vanilla Beans were subjected to the traditional curing process in Mexico. Odor-active potential from Beans including 23 compounds was monitored through the analysis of both free and glucosidically bound volatiles. 8 of them were aliphatic aldehydes, acids, alcohol and ketone. 15 molecules were shikimate derivatives in which 13 were detected in glucosylated form. Some glucosides were efficiently hydrolyzed while some others partly or not at all after 90 days of curing. Moreover kinetics of hydrolysis of glucosides were not the same. A major part of glucovanillin was hydrolyzed at the first stages of curing while some other glucosides at the advanced stages. Data support hypothesis that hydrolysis of glucosides during curing is rather enzymatic origin than chemical one. Free shikimate derivatives or those liberated from glucosides are prone to chemical or enzymatic interconversions leading to a significant change in the aroma profile of cured Vanilla.
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Vanilla
2010Co-Authors: Eric Odoux, Michel GrisoniAbstract:Vanilla is a legacy of Mexico and, like chocolate, it is a major global delicacy representing almost a half-billion euros in profits each year. Vanilla presents up-to-date reviews on the cultivation, curing, and uses of Vanilla. It provides unique and comprehensive coverage of the biology of the Vanilla vine, the properties of its aromatic Beans, and production processes worldwide. This globally relevant resource discusses biotechnology aimed at finding novel production methods of Vanilla and horticultural studies for improving yields and increasing plant resistance. It analyzes entomological issues related to pollination, studies on the chemistry and biochemistry of the curing process, and the advanced analytical chemistry needed to identify adulterations such as vanillin-spiked pods and synthetic vanillin. It also explores the relationship between fruit development anatomy and flavor quality. Vanilla is a universally appreciated flavor that is consumed worldwide. Contents: Vanilloid orchids: Systematics and evolution (Kenneth M. Cameron). Evolutionary processes and diversification in the genus Vanilla (Séverine Bory, Spencer Brown, Marie-France Duval, Pascale Besse). Conservation and movement of Vanilla germplasm (Michel Roux-Cuvelier, Michel Grisoni). Vanilla in herbaria (Marc Pignal). Biotechnological applications in Vanilla (Minoo Divakaran, K. Nirmal Babu, Michel Grisoni). Cultivation systems (Juan Hernández Hernández, Pesach Lubinsky). Virus diseases of Vanilla (Michel Grisoni, Michael Pearson, Karin Farreyrol). Fungal diseases of Vanilla (Mesak Tombe, Edward C.Y. Liew). Bio-ecology and control of an emerging Vanilla pest, the scale Conchaspis angraeci (Serge Quilici, Agathe Richard, Kenny Le Roux). Anatomy and biochemistry of Vanilla bean development (Vanilla planifolia G. Jackson) (Fabienne Lapeyre-Montes, Geneviève Conéjéro,Jean-Luc Verdeil, Eric Odoux). Vanilla curing (Eric Odoux). Developing the aromatic quality of cured Vanilla Beans (Eric Odoux). Morphological, chemical, sensory, and genetic specificities of Tahitian Vanilla (Sandra Lepers-Andrzejewski, Christel Brunschwig,François-Xavier Collard, Michel Dron). Microbial safety of cured Vanilla Beans (Samira Sarter). Authentication of Vanilla products (Jens-Michael Hilmer, Franz-Josef Hammerschmidt, Gerd Lösing). Vanilla use in colonial Mexico and traditional Totonac (Patricia Rain, Pesach Lubinsky). Vanilla's debt to Reunion Island (Raoul Lucas). Recognizing the quality and origin of Vanilla from Reunion Island: creating a PGI "Vanille de L'île de la Réunion" (Bertrand Côme). Vanilla production in Indonesia (Robber Zaubin, Mesak Tombe, Edward C.Y. Liew). Vanilla production in India (Y.R. Sarma, Joseph Thomas, B. Sasikumar, S. Varadarasan). Vanilla production in East Africa: Uganda, Tanzania, Kenya, and Eastern Democratic Republic of Congo (Clemens Fehr). Vanilla production in Mexico (Juan Hernández Hernández, Pesach Lubinsky). Vanilla production in China (Hengcang Zhou, Yunyue Wang, Hongyu Wang, Xurui, Dexin Chen). Vanilla production in French Polynesia (Sandra Lepers-Andrzejewski, Michel Dron). (Adapted from the publisher's summary)
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the relation between glucovanillin β d glucosidase activity and cellular compartmentation during the senescence freezing and traditional curing of Vanilla Beans
Annals of Applied Biology, 2006Co-Authors: Eric Odoux, Jacques Escoute, Jeanluc VerdeilAbstract:The aim of this research was to improve our understanding of the mechanism of glucovanillin hydrolysis by β-d-glucosidase activity in Vanilla Beans by studying their senescence, freezing and traditional curing. A batch of green pods from Madagascar was ripened at 30°C until fruits turned black; another batch was frozen for few days at −18°C and defrosted at 35°C for 24 h and a third batch was cured using traditional methods. During treatments, samples were analysed for the yield of glucovanillin hydrolysis, and β-glucosidase activity was measured. Cellular structures were also examined by light and transmission electron microscopy. Green fruits had a low yield of glucovanillin hydrolysis ( 95%), no measurable β-glucosidase activity and complete cellular degradation. Similar results were observed in Beans after defrosting. During curing, Beans had a medium yield of glucovanillin hydrolysis (<50%), no measurable β-glucosidase activity and partial cellular degradation compared with senescent or defrosted Beans. Results show that the mechanism of glucovanillin hydrolysis in Vanilla Beans is regulated by cellular compartmentation and that the β-glucosidase activity level is not the limiting factor for complete hydrolysis. If total decompartmentation is obtained, then complete glucovanillin hydrolysis is observed even if most of the β-glucosidase activity is lost. The β-glucosidase activity level only has an effect on glucovanillin hydrolysis kinetics.
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The relation between glucovanillin, β‐d‐glucosidase activity and cellular compartmentation during the senescence, freezing and traditional curing of Vanilla Beans
Annals of Applied Biology, 2006Co-Authors: Eric Odoux, Jacques Escoute, Jeanluc VerdeilAbstract:The aim of this research was to improve our understanding of the mechanism of glucovanillin hydrolysis by β-d-glucosidase activity in Vanilla Beans by studying their senescence, freezing and traditional curing. A batch of green pods from Madagascar was ripened at 30°C until fruits turned black; another batch was frozen for few days at −18°C and defrosted at 35°C for 24 h and a third batch was cured using traditional methods. During treatments, samples were analysed for the yield of glucovanillin hydrolysis, and β-glucosidase activity was measured. Cellular structures were also examined by light and transmission electron microscopy. Green fruits had a low yield of glucovanillin hydrolysis ( 95%), no measurable β-glucosidase activity and complete cellular degradation. Similar results were observed in Beans after defrosting. During curing, Beans had a medium yield of glucovanillin hydrolysis (
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GC–MS and GC–olfactometry analysis of aroma compounds in a representative organic aroma extract from cured Vanilla (Vanilla planifolia G. Jackson) Beans
Food Chemistry, 2006Co-Authors: Araceli Pérez Silva, Eric Odoux, Pierre Brat, Fabienne Ribeyre, G.c. Rodríguez-jimenes, V. J. Robles-olvera, M.a. García-alvarado, Ziya GunataAbstract:Volatile compounds from cured Vanilla Beans were extracted using organic solvents. Sensory analysis showed that the aromatic extract obtained with a pentane/ether (1/1 v/v) solvent mixture provided the extract most representative of Vanilla bean flavour. Sixty-five volatiles were identified in a pentane/ether extract by GC-MS analysis. Aromatic acids, aliphatic acids and phenolic compounds were the major volatiles. By GC-O analysis of the pentane/ether extract, 26 odour-active compounds were detected. The compounds guaiacol, 4-methylguaiacol, acetovanillone and vanillyl alcohol, found at much lower concentrations in Vanilla Beans than vanillin, proved to be as intense as vanillin.
Robert Verpoorte - One of the best experts on this subject based on the ideXlab platform.
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Identification of glucosides in green Beans of Vanilla planifolia Andrews and kinetics of Vanilla β-glucosidase
Food Chemistry, 2004Co-Authors: Mark J.w. Dignum, Rob Van Der Heijden, Josef Kerler, Chris Winkel, Robert VerpoorteAbstract:Natural Vanilla is extracted from the fruits of Vanilla planifolia. In the overall Vanilla aroma, minor compounds p-cresol, creosol, guaiacol and 2-phenylethanol have a high impact. This is shown by GC-Olfactometry analysis of cured Vanilla Beans. The presence of β-D-glucosides of these compounds was investigated, in order to determine if these compounds are derived from glucosides or if they are formed during the curing process via different pathways. Glucosides of vanillin, vanillic acid, p-hydroxy benzaldehyde, vanillyl alcohol, p-cresol, creosol and bis[4-(β-d-glucopyranosyloxy)-benzyl]-2-isopropyltartrate and bis[4-(β-d-glucopyranosyloxy)-benzyl]-2-(2-butyl)tartrate have been identified in a green bean extract. The kinetics of the β-glucosidase activity from green Vanilla Beans towards eight glucosides naturally occurring in Vanilla and towards p-nitrophenol were investigated. For glucosides of p-nitrophenol, vanillin and ferulic acid the enzyme had a Km of about 5 mM. For other glucosides (vanillic acid, guaiacol and creosol) the Km-values were higher (>20 mM). The Vmax was between 5 and 10 IU mg−1 protein for all glucosides tested. Glucosides of 2-phenylethanol and p-cresol were not hydrolysed. β-Glucosidase does not have a high substrate specificity for the naturally occurring glucosides compared to the synthetic p-nitrophenol glucoside (Km 3.3 mM, Vmax 11.5 IU mg−1 protein).
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Vanilla curing under laboratory conditions
Food Chemistry, 2002Co-Authors: Mark J.w. Dignum, Josef Kerler, Robert VerpoorteAbstract:Abstract A laboratory model curing is described in which the cured Vanilla Beans are analysed for enzyme activity and aroma. The activity of the enzymes was highest in green Beans. β-Glucosidase (β-Glu) could not be detected after 24 h of autoclaving. Peroxidase (PER) and protease (PROT) activity decreased, but were still present (20%) after 29 days. Phenylalanine ammonia lyase (PAL) survived autoclaving, but was not detected later in the process. Beans that were scalded for 20 min at 80 °C showed no detectable β-Glu and PAL activity, but PROT and PER were still active. Under traditional curing conditions glucovanillin (GV) and glucovanillic acid (GVA) were hydrolysed to vanillin and vanillic acid, respectively. Upon scalding for 20 min at 80 °C the concentration of glucosides was still high (after 16 day: GV 2000 ppm, GVA 700 ppm). This may be an indication that the normal scalding leads to inactivation of a non-specific glucosidase, while the prolonged scalding also inactivates a specific glucosidase.
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β-Glucosidase and peroxidase stability in crude enzyme extracts from green Beans of Vanilla planifolia Andrews
Phytochemical analysis : PCA, 2001Co-Authors: Mark J.w. Dignum, Josef Kerler, Robert VerpoorteAbstract:The extraction method for β-glucosidase from green Vanilla Beans has been studied. The effect of storage of green Beans and protein extracts on β-glucosidase and peroxidase activity was investigated: the best method, resulting in the highest enzyme activities, particularly for glucosidase, was through extraction of very fresh green Beans in the presence of BisTris propane buffer at pH 8. The best method for storage of the extracts was at −80°C after addition of 15% glycerol, when over 90% of initial activity was still present. Peroxidase activity did not change in frozen Beans or in frozen extracts. Copyright © 2001 John Wiley & Sons, Ltd.
Yonggan Chen - One of the best experts on this subject based on the ideXlab platform.
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Distinct Roles for Bacterial and Fungal Communities During the Curing of Vanilla.
Frontiers in microbiology, 2020Co-Authors: Yonggan Chen, Yingying CaiAbstract:Vanilla produces aroma after curing. There were a few reports about the possible involvement of microorganisms during the curing process. Bacterial and fungal community was analyzed to explore the distinct roles. Alpha diversity analysis indicated that the abundance and diversity of microorganisms did not increase regularly as the curing progressed. Weighted and unweighted principal coordinates analysis (PCoA) showed that the fungal community of blanching Beans was significantly different from those of the Vanilla Beans of other stages, respectively. Bacillus and Aspergillus were the dominant genus during the curing process. Correlation analysis indicated that the bacterial and fungal structure was positively related to the vanillin formation, respectively. The study was conducive to reveal the formation of flavor components and the biosynthesis of vanillin. Furthermore, it proposed the possible curing methods of regulating the bacterial and fungal community to increase vanillin formation.
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Metabolite Transformation and Enzyme Activities of Hainan Vanilla Beans During Curing to Improve Flavor Formation.
Molecules (Basel Switzerland), 2019Co-Authors: Yingying Cai, Yinghua Hong, Yonggan ChenAbstract:This paper compares the differences in metabolites of Vanilla Beans at five different curing stages. Key Vanilla flavors, vanillin precursors and main enzymes during the curing process of Hainan Vanilla Beans were also analyzed. Hundreds of metabolites were detected based on metabolic analyses of a widely targeted metabolome technique, compared with blanched Vanilla Beans (BVB), sweating Vanilla Beans (SVB) and drying Vanilla Beans (DVB), the total peak intensity of cured Vanilla Beans (CVB) is on the rise. The score plots of principal component analysis indicated that the metabolites were generally similar at the same curing stages, but for the different curing stages, they varied substantially. During processing, vanillin content increased while glucovanillin content decreased, and vanillic acid was present in sweating Beans, but its content was reduced in drying Beans. Both p-hydroxybenzaldehyde and p-hydroxybenzoic acid showed the maximum contents in cured Beans. Ferulic acid was mainly produced in drying Beans and reduced in cured Beans. p-coumaric acid increased during the curing process. Vanillyl alcohol in drying Beans (0.22%) may be formed by the hydrolysis of glucoside, whose conversion into vanillin may explain its decrease during the curing stage. β-Glucosidase enzymatic activity was not detected in blanched and sweating Beans, but was observed after drying. Peroxidase activity decreased during curing by 94% in cured Beans. Polyphenol oxidase activity was low in earlier stages, whereas cellulase activity in processed Beans was higher than in green Beans, except for cured Beans. This study contributes to revealing the formation of flavor components and the biosynthesis pathway of vanillin.
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Comparative metabolomics in Vanilla pod and Vanilla bean revealing the biosynthesis of vanillin during the curing process of Vanilla.
AMB Express, 2017Co-Authors: Yonggan Chen, Yinghua Hong, Yiming Fang, Lehe TanAbstract:High-performance liquid chromatography–mass spectrometry (LC–MS) was used for comprehensive metabolomic fingerprinting of Vanilla fruits prepared from the curing process. In this study, the metabolic changes of Vanilla pods and Vanilla Beans were characterized using MS-based metabolomics to elucidate the biosynthesis of vanillin. The Vanilla pods were significantly different from Vanilla Beans. Seven pathways of vanillin biosynthesis were constructed, namely, glucovanillin, glucose, cresol, capsaicin, vanillyl alcohol, tyrosine, and phenylalanine pathways. Investigations demonstrated that glucose, cresol, capsaicin, and vanillyl alcohol pathway were detected in a wide range of distribution in microbial metabolism. Thus, microorganisms might have participated in vanillin biosynthesis during Vanilla curing. Furthermore, the ion strength of glucovanillin was stable, which indicated that glucovanillin only participated in the vanillin biosynthesis during the curing of Vanilla.
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Contribution of Bacillus Isolates to the Flavor Profiles of Vanilla Beans Assessed through Aroma Analysis and Chemometrics
Molecules (Basel Switzerland), 2015Co-Authors: Yonggan Chen, Yiming Fang, Lehe TanAbstract:Colonizing Bacillus in Vanilla (Vanilla planifolia Andrews) Beans is involved in glucovanillin hydrolysis and vanillin formation during conventional curing. The flavor profiles of Vanilla Beans under Bacillus-assisted curing were analyzed through gas chromatography-mass spectrometry, electronic nose, and quantitative sensory analysis. The flavor profiles were analytically compared among the Vanilla Beans under Bacillus-assisted curing, conventional curing, and non-microorganism-assisted curing. Vanilla Beans added with Bacillus vanillea XY18 and Bacillus subtilis XY20 contained higher vanillin (3.58%±0.05% and 3.48%±0.10%, respectively) than Vanilla Beans that underwent non-microorganism-assisted curing and conventional curing (3.09%±0.14% and 3.21%±0.15%, respectively). Forty-two volatiles were identified from endogenous Vanilla metabolism. Five other compounds were identified from exogenous Bacillus metabolism. Electronic nose data confirmed that Vanilla flavors produced through the different curing processes were easily distinguished. Quantitative sensory analysis confirmed that Bacillus-assisted curing increased vanillin production without generating any unpleasant sensory attribute. Partial least squares regression further provided a correlation model of different measurements. Overall, we comparatively analyzed the flavor profiles of Vanilla Beans under Bacillus-assisted curing, indirectly demonstrated the mechanism of Vanilla flavor formation by microbes.
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Involvement of Colonizing Bacillus Isolates in Glucovanillin Hydrolysis during the Curing of Vanilla planifolia Andrews.
Applied and environmental microbiology, 2015Co-Authors: Yonggan Chen, Li Jihua, He Shuzhen, Yiming FangAbstract:Vanilla Beans were analyzed using biochemical methods, which revealed that glucovanillin disperses from the inner part to the outer part of the Vanilla bean during the curing process and is simultaneously hydrolyzed by β-d-glucosidase. Enzymatic hydrolysis was found to occur on the surface of the Vanilla Beans. Transcripts of the β-d-glucosidase gene (bgl) of colonizing microorganisms were detected. The results directly indicate that colonizing microorganisms are involved in glucovanillin hydrolysis. Phylogenetic analysis based on 16S rRNA gene sequences showed that the colonizing microorganisms mainly belonged to the Bacillus genus. bgl was detected in all the isolates and presented clustering similar to that of the isolate taxonomy. Furthermore, inoculation of green fluorescent protein-tagged isolates showed that the Bacillus isolates can colonize Vanilla Beans. Glucovanillin was metabolized as the sole source of carbon in a culture of the isolates within 24 h. These isolates presented unique glucovanillin degradation capabilities. Vanillin was the major volatile compound in the culture. Other compounds, such as α-cubebene, β-pinene, and guaiacol, were detected in some isolate cultures. Colonizing Bacillus isolates were found to hydrolyze glucovanillin in culture, indirectly demonstrating the involvement of colonizing Bacillus isolates in glucovanillin hydrolysis during the Vanilla curing process. Based on these results, we conclude that colonizing Bacillus isolates produce β-d-glucosidase, which mediates glucovanillin hydrolysis and influences flavor formation.
Krzysztof N Waliszewski - One of the best experts on this subject based on the ideXlab platform.
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Effect of endogenous and exogenous enzymatic treatment of green Vanilla Beans on extraction of vanillin and main aromatic compounds
Journal of Food Science and Technology, 2018Co-Authors: Violeta T Pardio, Argel Flores, Karla M. López, David I. Martínez, Ofelia Márquez, Krzysztof N WaliszewskiAbstract:Endogenous and exogenous enzymatic hydrolysis carried out to obtain Vanilla extracts with higher concentrations of vanillin using green Vanilla Beans. Sequences initiated with freezing of green Vanilla Beans at − 1 °C for 24 h, followed by endogenous hydrolysis under optimal β-glucosidase activity at 4.2 and 35 °C for 96 h, exogenous hydrolysis with Crystalzyme PML-MX at pH 5.0 and 40 °C for 72 h, and ethanol extraction at 40% (v v^−1) for 30 days. In the proposed method, 200 g of fresh green Vanilla Beans with 84% moisture (32 g dry base) were used to obtain a liter of single fold Vanilla extract. This method allowed the release of 82.57% of the theoretically available vanillin from its precursor glucovanillin with 5.78 g 100 g^−1 green Vanilla Beans (dry base). Vanillic acid, p -hydroxybenzaldehyde and vanillyl alcohol were also released and found in commercial and enzymatic extracts. Glucovanillin was detected in commercial and traditional extracts but was absent in enzymatic extracts, indicating incomplete hydrolysis during the curing process. An in vitro assay was conducted to determine if the presence of peroxidase during hydrolysis might affect overall vanillin concentration. Results showed that POD can use vanillin as a substrate under conditions similar to those in which hydrolysis was conducted (pH 5.0 and 50 °C), possibly explaining why vanillin concentration was not complete at the end of the process.
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Effects of different Vanilla extraction methods on sensory and colour properties of Vanilla ice creams during storage
International Journal of Food Science & Technology, 2010Co-Authors: Violeta T Pardio, Krzysztof N Waliszewski, Argel FloresAbstract:Summary The effects of enzyme assisted Vanilla extract (EAVE), traditional Vanilla extract made from the same mature Vanilla Beans and commercial Vanilla extract, adjusted to 0.1% vanillin concentration, on the sensory and colour properties of Vanilla ice cream were studied. For the production of 1 kg of ice cream, Vanilla extracts contributed 5 mg of vanillin but each extract contributed different amounts of non-vanillin flavour compounds. Flavour and odour parameters of ice creams did not show changes during 3 weeks of storage while colour parameters decreased in ice cream made with EAVE from the first day of manufacture. When EAVE was used, it produced a whiter colour in the ice cream, which was found to be less stable from the second week of storage. This observation was confirmed with the measurement of L and chroma colour parameters.
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The effect of thermal treatment on β‐glucosidase inactivation in Vanilla bean (Vanilla planifolia Andrews)
International Journal of Food Science & Technology, 2008Co-Authors: Ofelia Márquez, Krzysztof N WaliszewskiAbstract:Summary The conditions for enzyme activity (pH and temperature) and kinetic parameters for the thermal inactivation of β-glucosidase enzyme in Vanilla Beans have been investigated. The maximum enzyme activity was detected at pH 6.5 and 38 °C. The values obtained for Vmax and Km were 62.05 units and 2.07 mm, respectively. When hot water treatment (the most practical method of Vanilla bean killing) was applied, β-glucosidase treated at pH 6.0 and 60 °C for 3 min lost 51% of activity, while at 70 °C for 90 s the enzyme lost 60% of activity and at 80 °C for 30 s the enzyme lost 48% of its activity. When Vanilla Beans were cured in an oven at 60 °C for 36 to 48 h all β-glucosidase activity was lost.
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Purification and characterization of cell wall-bound peroxidase from Vanilla bean
LWT - Food Science and Technology, 2008Co-Authors: Ofelia Márquez, Krzysztof N Waliszewski, Rosa M. Oliart, Violeta T PardioAbstract:Abstract A cold-active ionically bound cell wall peroxidase was purified from a polyvinylpolypyrrolidone extract of mature Vanilla Beans by ultra filtration of 10 kDa and gel filtration chromatography on Sephacryl S-200. The M r was 46.5 kDa determined by electrophoresis on SDS–PAGE, while native gel filtration confirmed tetramer enzyme form of approximately 186 kDa. The optimum pH and temperature were 3.8 and 16 °C, respectively, as determined with guaiacol as the substrate ( K m 3.8 mmol/L). The p I was approximately 7.7. The POD was inhibited by 1,4-dithiothreitol, β -mercaptoethanol and sodium azide. The POD showed decreasing activity in the presence of ascorbic acid, NaEDTA and sodium dodecyl sulfate at 1 mmol/L. The enzyme lost 80% of its activity in the presence of 20% ethanol. These results will permit better understanding of POD role in Vanilla curing process.
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effect of hydration and enzymatic pretreatment of Vanilla Beans on the kinetics of vanillin extraction
Journal of Food Engineering, 2007Co-Authors: Krzysztof N Waliszewski, Sandy L Ovando, Violeta T PardioAbstract:Abstract We have studied the effects of prehydration and enzymatic pretreatment of Vanilla Beans by three cellulolytic enzyme products: Crystalzyme PML-MX, Zymafilt L-300 and Novozym. Vanilla Beans were cut in pieces and hydrated in water and with 5% ethanol up to 72 h and reducing sugars and glucose were measured. Prehydration conditions (5% ethanol at 48 h) were used for the study of the effect of pH and temperature on the kinetics of vanillin liberation during 26 h of treatment. Finally, the most adequate conditions of enzymatic pretreatment of each preparation were applied to Vanilla Beans submitted to the process of vanillin ethanolic extraction showing that enzymatic pretreatment enriches and can as much as double vanillin content in the extract.
Mark J.w. Dignum - One of the best experts on this subject based on the ideXlab platform.
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Identification of glucosides in green Beans of Vanilla planifolia Andrews and kinetics of Vanilla β-glucosidase
Food Chemistry, 2004Co-Authors: Mark J.w. Dignum, Rob Van Der Heijden, Josef Kerler, Chris Winkel, Robert VerpoorteAbstract:Natural Vanilla is extracted from the fruits of Vanilla planifolia. In the overall Vanilla aroma, minor compounds p-cresol, creosol, guaiacol and 2-phenylethanol have a high impact. This is shown by GC-Olfactometry analysis of cured Vanilla Beans. The presence of β-D-glucosides of these compounds was investigated, in order to determine if these compounds are derived from glucosides or if they are formed during the curing process via different pathways. Glucosides of vanillin, vanillic acid, p-hydroxy benzaldehyde, vanillyl alcohol, p-cresol, creosol and bis[4-(β-d-glucopyranosyloxy)-benzyl]-2-isopropyltartrate and bis[4-(β-d-glucopyranosyloxy)-benzyl]-2-(2-butyl)tartrate have been identified in a green bean extract. The kinetics of the β-glucosidase activity from green Vanilla Beans towards eight glucosides naturally occurring in Vanilla and towards p-nitrophenol were investigated. For glucosides of p-nitrophenol, vanillin and ferulic acid the enzyme had a Km of about 5 mM. For other glucosides (vanillic acid, guaiacol and creosol) the Km-values were higher (>20 mM). The Vmax was between 5 and 10 IU mg−1 protein for all glucosides tested. Glucosides of 2-phenylethanol and p-cresol were not hydrolysed. β-Glucosidase does not have a high substrate specificity for the naturally occurring glucosides compared to the synthetic p-nitrophenol glucoside (Km 3.3 mM, Vmax 11.5 IU mg−1 protein).
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Vanilla curing under laboratory conditions
Food Chemistry, 2002Co-Authors: Mark J.w. Dignum, Josef Kerler, Robert VerpoorteAbstract:Abstract A laboratory model curing is described in which the cured Vanilla Beans are analysed for enzyme activity and aroma. The activity of the enzymes was highest in green Beans. β-Glucosidase (β-Glu) could not be detected after 24 h of autoclaving. Peroxidase (PER) and protease (PROT) activity decreased, but were still present (20%) after 29 days. Phenylalanine ammonia lyase (PAL) survived autoclaving, but was not detected later in the process. Beans that were scalded for 20 min at 80 °C showed no detectable β-Glu and PAL activity, but PROT and PER were still active. Under traditional curing conditions glucovanillin (GV) and glucovanillic acid (GVA) were hydrolysed to vanillin and vanillic acid, respectively. Upon scalding for 20 min at 80 °C the concentration of glucosides was still high (after 16 day: GV 2000 ppm, GVA 700 ppm). This may be an indication that the normal scalding leads to inactivation of a non-specific glucosidase, while the prolonged scalding also inactivates a specific glucosidase.
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β-Glucosidase and peroxidase stability in crude enzyme extracts from green Beans of Vanilla planifolia Andrews
Phytochemical analysis : PCA, 2001Co-Authors: Mark J.w. Dignum, Josef Kerler, Robert VerpoorteAbstract:The extraction method for β-glucosidase from green Vanilla Beans has been studied. The effect of storage of green Beans and protein extracts on β-glucosidase and peroxidase activity was investigated: the best method, resulting in the highest enzyme activities, particularly for glucosidase, was through extraction of very fresh green Beans in the presence of BisTris propane buffer at pH 8. The best method for storage of the extracts was at −80°C after addition of 15% glycerol, when over 90% of initial activity was still present. Peroxidase activity did not change in frozen Beans or in frozen extracts. Copyright © 2001 John Wiley & Sons, Ltd.
