Effects of different vanilla extraction methods on sensory and colour properties of vanilla ice creams during storage

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.     

GC–MS and GC–olfactometry analysis of aroma compounds in a representative organic aroma extract from cured vanilla (Vanilla planifolia G. Jackson) beans

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.     

Effect of Tissue Disruption by Different Methods Followed by Incubation with Hydrolyzing Enzymes on the Production of Vanillin from Tongan Vanilla Beans

Vanilla is one of the most popular and valuable flavorings worldwide. Natural vanilla is extracted from the cured vanilla pods of Vanilla planifolia. The main aromatic compound in vanilla is vanillin, a phenolic aldehyde, which is produced by enzymatic hydrolysis of glucovanillin during the curing process. Although the amount of glucovanillin in the uncured green bean is present at the level of 10–15%, only an average of about 2% vanillin yield results from the traditional curing process. Therefore, the aim of the experiment was to increase the vanillin yield by obtaining the maximum conversion of glucovanillin. This was obtained by the addition of exogenous cellulase, pectinase, and beta glucosidase enzymes and cellular-damaging techniques on green Tongan vanilla beans to enhance the interaction between glucovanallin substrate and enzymes and successfully achieved vanillin production ranging from 4.25 to 7.00% on a dry weight basis. These techniques may be further refined and translated into industrial curing practices for improvement of natural vanillin yield from vanilla beans.     

Enzyme-Assisted Process for Production of Superior Quality Vanilla Extracts from Green Vanilla Pods Using Tea Leaf Enzymes

Vanilla planifolia Andrews is a perennial tropical vine and is an orchid grown for its pleasant flavor. There is an increasing trend world over for using natural flavors. Vanilla being an important food flavoring ingredient, the demand for natural vanilla extract is increasing. Hence, the aim of the present study was to prepare vanilla extract from green beans without going through the elaborate and time-consuming conventional curing process. Vanilla beans after size reduction were mixed in a suitable proportion with tea leaf enzyme extract (TLEE) and incubated to facilitate action of enzymes on vanilla flavor precursors. The beans mix was squeezed, and the filtrate was treated with ethanol to extract the vanilla flavor. TLEE-treated extracts had higher vanillin content (4.2%) compared to Viscozyme extract (2.4%). Also, it had higher intensity of vanilla flavor, sweet, and floral notes. Further, electronic nose analysis confirmed the discrimination between extracts. It was concluded that the use of TLEE is very much useful to obtain higher yield of vanilla extract and superior quality vanilla flavor, which avoids the traditional laborious and time-consuming curing process.     

香草兰豆荚发酵过程中挥发性成分的变化

为研究香草兰发酵过程中挥发性成分的累积过程,采用了混合溶剂(乙醚/正戊烷=1:1,v/v)提取结合GC-MS的方法进行定性定量分析,并以DB-5及DB-Wax两种毛细管柱为分离柱分别进行了实验。结果表明:以DB-5毛细管柱为分离柱时,检测出45种挥发性物质,鲜豆荚、杀青豆荚、发汗豆荚、干燥豆荚及陈化豆荚分别检测出19、17、25、33、37种挥发性成分;以DB-Wax毛细管柱为分离柱时,检测出53种物质,五种豆荚中分别检测出20、21、27、38、46种挥发性成分。两种方法共分离检测出69种物质。挥发性成分主要在干燥及陈化阶段产生并累积,其中含量逐渐增加且在陈化豆荚中含量较高的有乙酸、愈创木酚、香兰醇、十六酸等物质,反式-2-癸烯醛、硬脂酸甲酯、山嵛醇等物质仅出现在发酵前期,己二酸二(2-乙基己)酯、2-乙基己基乙酸酯的含量在发酵过程中逐渐降低。成熟豆荚的香气是由多种前体物的代谢产物混合而形成。     

Biovanillin from agro wastes as an alternative food flavour

This review provides an overview of biovanillin production from agro wastes as an alternative food flavour. Biovanillin is one of the widely used flavour compounds in the foods, beverages and pharmaceutical industries. An alternative production approach for biovanillin as a food flavour is hoped for due to the high and variable cost of natural vanillin as well as the limited availability of vanilla pods in the market. Natural vanillin refers to the main organic compound that is extracted from the vanilla bean, as compared to biovanillin, which is produced biologically by microorganisms from a natural precursor such as ferulic acid. Biovanillin is also reviewed as a potential bioflavour produced by microbial fermentation in an economically feasible way in the near future. In fact, we briefly discuss natural, synthetic and biovanillin and the types of agro wastes that are useful as sources for bioconversion of ferulic acid into biovanillin. The subsequent part of the review emphasizes the current application of vanillin as well as the utilization of biovanillin as an alternative food flavour. The final part summarizes biovanillin production from agro wastes that could be of benefit as a food flavour derived from potential natural precursors.© 2012 Society of Chemical Industry     

HS-SPME-GC-MS分析不同产地香荚兰豆挥发性成分

目的：分析不同产地香荚兰豆挥发性成分的组成。方法：采用顶空固相微萃取-气相色谱-质谱联用技术,结合惠普-化学源化学工作站对不同产地的香荚兰豆中挥发性化学成分进行定性分析,以峰面积归一化法计算各组分的相对含量,并通过主成分分析和聚类分析2 种化学计量法对数据进行分析。结果：初步鉴定出104 种化合物,不同产地香荚兰豆挥发性成分有一定差异。结论：此方法稳定可靠,适用于香荚兰豆挥发性成分的快速分析,可为香荚兰豆的质量评价提供一定的科学依据。     

VANILLA PRODUCTION: TECHNOLOGICAL,CHEMICAL, AND BIOSYNTHETIC ASPECTS

This review covers the most recent literature on vanilla research. Besides the curing process, chemistry in green and cured beans, as well as studies on the biosynthetic pathways of the most important aroma compounds are discussed. Despite intensive research on the curing process, the traditional curing procedures are still widely used. The role of enzymes involved in the curing process is not fully understood.

The biosynthesis of vanilla aroma compounds is still under investigation. Data obtained from plant cell cultures are not always in accordance with those from the plant. The glycosylation of the compounds in vivo is still a point of study. Alternative routes to vanillin involving microbial biotransformations are outlined.     

The effect of thermal treatment on β‐glucosidase inactivation in vanilla bean (Vanilla planifolia Andrews)

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 V_max and K_m 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.     

Vanilla- Its Science of Cultivation,Curing, Chemistry,and Nutraceutical Properties

Vanilla is a tropical orchid belonging to the family Orchidaceae and it is mainly used in food, perfumery, and pharmaceutical preparations. The quality of the bean depends on the volatile constituent's, viz., the vanillin content, the species of the vine used, and the processing conditions adopted. Hence, proper pollination during flowering and curing by exercising utmost care are the important aspects of vanilla cultivation. There are different methods of curing, and each one is unique and named after the places of its origin like Mexican process and Bourbon process. Recently, Central Food Technological Research Institute, Mysore has developed know-how of improved curing process, where the green vanilla beans are cured immediately after harvest and this process takes only 32 days, which otherwise requires minimum of 150–180 days as reported in traditional curing methods. Vanillin is the most essential component of the 200 and odd such compounds present in vanilla beans. Vanillin as such has not shown any antioxidant properties, it is along with other compounds has got nutraceutical properties and therefore its wide usage. The medicinal future of vanilla may definitely lie in further research on basic science and clinical studies on the constituents and their mechanism of action.     

Factors influencing quality variation in cocoa (Theobroma cacao) bean flavour profile — A review

This review examined the factors that influence flavour volatiles of cocoa beans and the volume of work that needs to be done on these factors and their impact on the flavour volatiles of commercial cocoa beans. Cocoa bean flavour is one of the most important quality attributes as flavour is central to acceptability of cocoa beans and cocoa products such as chocolate. The complex composition of cocoa bean flavour depends on bean genotype, postharvest treatments such as pulp pre-conditioning, fermentation and drying, industrial processes such as roasting as well as the type of soil and age of cocoa tree. The bean genotype determines the chemical composition of the bean, specifically the contents of bean storage proteins, polysaccharides, and polyphenols. This determines the quantities and type of precursors formed during fermentation and drying processes leading to flavour formation, hence, influencing both flavour type and intensity. Cocoa bean fermentation and drying result in the breakdown of the storage proteins by endogenous proteases into amino acids and short chain oligopeptides while the polysaccharides are also degraded by invertase to glucose and fructose. The amino acids, oligopeptides, glucose and fructose react with each other during the roasting process to produce the typical cocoa flavour volatiles. Polyphenols are also oxidized by polyphenol oxidase during fermentation and drying which reduce the astringency and bitterness of the beans, thus, enhancing the flavour of cocoa beans. However, the extent to which other factors such as age of the cocoa tree and soil chemical compositions influence the formation of flavour precursors and their relationships with final flavour quality remains unclear. With increasing demand for sustainable production of high quality cocoa beans, greater understanding of factors contributing to the variations in flavour character would have significant commercial implications.     

Quality of cocoa beans dried using a direct solar dryer at different loadings

In this study fermented cocoa beans were dried in a direct solar dryer at three levels of loading (20, 30 and 60 kg). Surface mouldiness was found to be heavy in the 60 kg treatment, with beans appearing blackish. All the dried beans were reasonably acceptable in terms of vinegary odour and weak in alcohol odour. Weak odour was also detected for the faecal, rancid and cheesy odours. The 60 kg treatment was rated strong for wet sock odour due to poor drying condition. A significant difference (P < 0.05) was found between the 60 kg treatment and the lower loading treatments for pH and titratable acidity. A cut test showed that the lower loading treatments resulted in a higher percentage of brown beans. The 20 kg treatment showed the highest cut test score, which is significantly different (P < 0.05) from the 60 kg treatment. Fermentation index also showed a tendency for lower loading treatments to have a higher index. No significant difference (P > 0.05) was found among the treatments in terms of cocoa, astringency, bitterness and sourness flavour notes. However, better flavour was observed for beans from the 20 kg treatment. No mouldy off flavour was found in any of the dried beans. Overall quality assessment showed that the 20 kg treatment was able to produce reasonably good‐quality beans as compared to other loadings and therefore is recommended for the direct solar dryer. Copyright © 2006 Society of Chemical Industry     

Volatile constituents of roasted tigernut oil (Cyperus esculentus L.)

BACKGROUND: Volatile compounds play a key role in determining the sensory appreciation of vegetable oils. In this study a systematic evaluation of odorants responsible for the characteristic flavour of roasted tigernut oil was carried out. RESULTS: A total of 75 odour‐active volatiles were identified. From these, 13 aroma compounds showing high flavour dilution factors in the range of 16 to 128 were quantified by their odour activity values (OAVs). On the basis of high OAVs in oil, the following aroma compounds [vanillin (chocolate, sweet vanilla), 5‐ethylfurfural (caramel, spicy), 2,3‐dihydro‐3,5‐dihydroxy‐6‐methyl‐4H‐pyran‐4‐one (caramel), phenyl acetaldehyde (honey‐like), ethanone, 1‐(4‐hydroxy‐3‐methoxyphenyl) (faint vanilla)] were elucidated as important contributors to the overall chocolate, sweet vanilla, butterscotch aroma of the oil. CONCLUSION: Odorants with high concentrations in the roasted tigernut oil such as 5‐hydroxymethylfurfural, ethyl hexadecanoate, n‐propyl‐9,12‐octadecadienoate gave relatively low OAVs, so their contributions to the overall orthonasal aroma impression of roasted tigernut oil can be assumed to be low. © 2012 Society of Chemical Industry     

Fermentation of cocoa beans: influence of microbial activities and polyphenol concentrations on the flavour of chocolate

BACKGROUND: Spontaneous cocoa bean fermentation is characterised by a succession of microbial activities. Cocoa flavour precursors are developed during fermentation and drying of cocoa beans. Polyphenols and alkaloids contribute to astringency and bitterness of cocoa and chocolate. RESULTS: Population dynamics, metabolite target analyses, and chocolate production were performed for seven independent spontaneous cocoa bean heap fermentations in Ghana. Although the same micro‐organisms were involved in these heaps, carried out at different farms or in different seasons, heap temperatures and microbial metabolite concentrations were different. This could be due to heterogeneity and size of the heaps, but was mainly ascribed to microbial variability. Indeed, differences in microbial activity could be linked with the flavour of chocolates made from the corresponding dried, fermented cocoa beans. Whereas the polyphenol and alkaloid contents of cocoa beans were crop‐ and heap‐dependent, epicatechin and theobromine levels decreased during fermentation due to diffusion out of the bean cotyledons and polyphenol oxidation and condensation. Residual levels were responsible for the degree of bitterness of the final chocolates. CONCLUSION: Differences in microbial activities between different heap fermentations can result in dried fermented cocoa beans and chocolates with different flavour characteristics. Hence, fermentation control may direct the flavour of chocolate. Copyright © 2008 Society of Chemical Industry     

Hochdruckflüssigchromatographische Untersuchung von Vanille-CO2-Hochdruckextrakten

HPLC has been used for the determination of vanillin,p-hydroxybenzaldehyde, vanillic acid,p-hydroxybenzoic acid, ethyl vanillin, piperonal and coumarin in CO₂ extracts and alcoholic extracts of vanilla beans. Ethyl vanillin, piperonal and coumarin were found in none of the samples. By measuring vanillin,p-hydroxybenzaldehyde, vanillic acid andp-hydroxybenzoic acid a great difference between the amount and the ratio of these main components of the usual alcoholic vanilla extracts and the CO₂ vanilla extracts was shown. The present requirements for vanilla extracts and products containing vanilla extracts refer only to the composition of alcoholic extracts for which, in contrast to CO₂ vanilla extracts, many studies have been published. The critical examination of products containing CO₂ vanilla extracts by using the ratios of vanilla compounds found in the present literature could lead to erroneous complaints. For the purpose of estimating the influence of the extraction solvent on the yield of vanillin, one sample of vanilla beans of each provenance was extracted besides the CO₂ extraction also with the solvents ethanol-water according to the method for a single-fold extract and with the solvents dichloromethane and hexane. In all three cases dichloromethane was found to be the best solvent. Furthermore, the ethanol-water extraction tended to give 6–22% more vanillin than the CO₂ extraction. To achieve unequivocal results, the examination of more samples is necessary.     

Effects of killing conditions of vanilla (Vanilla planifolia,Andrews) pods during the curing process on aroma composition of pod ethanol extract

The effects on the aroma compositions of ethanol extracts obtained by traditional and enzyme‐assisted methods from seven killing conditions used in vanilla pod curing were studied. Two procedures of vanilla pod killing consisted of either freezing pods at ?10 °C for 24 h or immersing pods in 80 °C water for 10 s each of three times with 30 s intervals resulted in the highest vanillin values in terms percentage of dry weight of the bean (2.84 and 2.96), 4‐hydroxybenzaldehyde (0.18 and 0.20), vanillyl alcohol (0.56 and 0.57) and vanillic acid (0.18 and 0.19 respectively) when traditional vanilla ethanol extraction was used. When this extract was aged for 3 months it showed improvement in flavour compounds. Enzyme‐assisted vanilla ethanol extraction showed a higher content of flavour compounds than traditional extract, for example vanillin 4.38% and 2.96% respectively. Only vanillic acid levels were improved after ageing of the enzyme‐assisted extracts.     

Relating consumer preferences to sensory and physicochemical properties of dry beans (Phaseolus vulgaris)

BACKGROUND: Dry beans (Phaseolus vulgaris) have a range of varieties, colours and sizes. Differences in physicochemical and sensory properties influence consumer choices for beans. This study related consumer preferences to sensory and physico‐chemical properties of selected bean varieties—Jenny, Kranskop, PAN 148, AC Calmont, PAN 150 and Mkuzi—grown in Mpumalanga (MP) and Free State (FS) in South Africa. RESULTS: Significant (P < 0.05) variety, location as well as location × variety interaction effects were found for both physico‐chemical and sensory properties of beans. Jenny‐FS, Mkuzi and PAN 148‐MP beans had relatively long cooking times (>60 min). Some beans (e.g. PAN 150 and Mkuzi beans) were described as bitter, soapy and metallic with a raw‐bean flavour whereas more preferred beans (e.g. Jenny‐MP, Kranskop‐MP) were sweet, soft and with a cooked‐bean flavour. CONCLUSION Apart from small seed size, sensory characteristics such as bitter taste, soapy and metallic mouthfeel and hard texture contributed to consumers' dislike of certain bean varieties. The sweet taste, cooked‐bean flavours, soft and mushy textures of the most accepted varieties seemed to be related to beans with good hydration capacities that facilitated softening during cooking. Copyright © 2007 Society of Chemical Industry     

Analysis of Tahiti vanilla by high-performance liquid chromatography

In the literature there is contradictory information on the compounds of Tahiti vanilla, particularly concerning the piperonal content. Because of this, Tahitian beans and Tahiti vanilla resinoid were analysed by HPLC. Compared with results obtained onVanilla planifolia, the Tahitian beans contained relatively low amounts of vanillin and vanillic acid, relatively high amounts ofp-hydroxybenzoic acid and considerable amounts of anisic acid and anisyl alcohol. Furthermore, although anisaldehyde was detectable, 3-ethoxy-4-hydroxy-benzaldehyde (ethylvanillin), coumarin and piperonal were not. The resinoid contained the same compounds as the beans in the expected amounts and ratios. It has to be supposed that reports of positive piperonal results refer to research on adulterated vanilla beans.

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Hochdruckflüssigchromatographische Untersuchung von Tahiti-Vanille

Zusammenfassung In der Literatur finden sich widersprüchliche Angaben über die Zusammensetzung von Tahiti-Vanille, insbesondere im Hinblick auf einen Piperonalgehalt. Mittels HPLC wurden Untersuchungen an Tahiti-Vanille-Schoten und Tahiti-Vanille-Resinoid durchgeführt. Im Vergleich mitVanilla planifolia enthielten die Schoten relativ niedrige Gehalte an Vanillin und Vanillinsäure, relativ hohe Gehalte anp-Hydroxybenzoesäure sowie erhebliche Mengen an Anissäure und Anisalkohol. Weiterhin war Anisaldehyd, nicht jedoch 3-Ethoxy-4-hydroxy-benzaldehyd (Ethylvanillin49d), Cumarin oder Piperonal nachweisbar. Im Resinoid lagen die gleichen Inhaltsstoffe vor wie in den Schoten und entsprachen hinsichtlich Menge und Mengenverhältnis den erwarteten Werten. Es wird vermutet, daß die positiven Piperonalbefunde aus der Literatur auf einer Untersuchung verfälschter Vanilleschoten basieren.

     

Comparison of enzyme activities involved in flavour precursor formation in unfermented beans of different cocoa genotypes

The activities of endoprotease, aminopeptidase, carboxypeptidase and invertase (cotyledon and pulp) were studied in unfermented beans of 10 genotype samples with different flavour characteristics (high and low cocoa flavour). Analysis of variance showed that significant differences in enzyme activities exist between certain genotypes. Aminopeptidase and endoprotease activities in beans of the PA7 genotype were higher than in all others. Principal component analysis (PCA) showed that the PA7 genotype (high cocoa flavour) was very different from the UIT1 genotype (low cocoa flavour). Although significant differences exist, no simple and general relationship is established between the flavour potential of a genotype and the level of key enzyme activities in unfermented beans. Carboxypeptidase is of key importance for peptide and free amino acid formation, but differences in enzyme activity could not be correlated to flavour potential of the genotype. It is suggested that the level of enzyme activities present in unfermented beans is not a limiting factor for optimal formation of flavour precursors during the fermentation process. © 2000 Society of Chemical Industry     

A review on conventional and biotechnological approaches in white pepper production

White pepper is the dried seeds obtained from pepper berries (Piper nigrum L.) after the removal of the pericarp. It has been widely used as seasoning and condiments in food preparation. Globally, white pepper fetches a higher price compared to black pepper due to its lighter colour, preferable milder flavour and pungency. Increasing global demand of the spice outpaced the supply as the conventional production method used is laborious, lengthy and also not very hygienic. The most common conventional method is water retting but can also include pit soil, chemical, boiling, steaming and mechanical methods. The introduction of a biotechnological approach has gained a lot of interest, as it is a more rapid, convenient and hygienic method of producing white pepper. This technique involves the application of microorganisms and/or enzymes. This review highlights both conventional and latest biotechnological processes of white pepper production. © 2018 Society of Chemical Industry