What is artificial vanilla?

In this brief guide, we will answer the query, “What is artificial vanilla?” and will discuss what is vanilla and how it is made?

What is artificial vanilla?

Artificial vanilla is made of vanillin, which naturally exists in vanilla beans and lends the taste its unique aroma. Vanillin is a specialized metabolite and the main ingredient of vanilla extract that occurs in concentration of 1.0–2.0% w/w in cured vanilla beans. Vanillin (4-hydroxy-3-methoxybenzaldehyde) has different functional groups, like aldehyde, hydroxyl and ether attached to an aromatic ring. Vanillin is either isolated from vanilla extract or is chemically synthesized from guaiacol (1). Wood pulp waste is one source of artificial vanillin, but it has lately gone out of favor, as have other sources such as coke, cow manure, castor gland secretions (which are conveniently situated near a beaver’s anus), clove oil, pine bark, and fermented bran husks.

What is vanilla?

The chemical formula for vanillin is C8H8O3, and it is an organic molecule. A phenolic aldehyde is what it is. Aldehyde, hydroxyl, and ether are a few of its functional groups. Vanilla bean extract is mostly composed of this compound. As a flavoring ingredient in foods, drinks, and medicines, synthetic vanillin has surpassed genuine vanilla extract in popularity. Vanilla is a mixture of ~ 200 compounds; however, its characteristic flavor and fragrance comes mainly from the molecule vanillin (2).

The food business uses both vanillin and ethyl vanillin, the latter of which is more costly but has a greater flavor. Vanillin has a methoxy group (OCH3), while this compound has an ethoxy group (OCH2CH3).

Beyond vanillin, there are hundreds of other components in pure natural vanilla extract. Pure vanillin, generally synthetic, is a common ingredient in artificial vanilla flavorings. Natural vanilla extract is difficult to come by and prohibitively expensive, hence synthetic preparations of its primary component have long been considered an option. Eugenol was used as the starting point for the first commercial synthesis of vanillin (4-allyl-2-methoxyphenol). Artificial vanillin is now manufactured from guaiacol or lignin, depending on availability.

Although, the chemical synthesis of vanillin is cost effective but is restricted due to its adverse impacts on the environment and human health. Thus, the application of chemically synthesized vanillin is prohibited in the food industry by food-safety control bureaus globally. Nowadays, more focus is on naturally derived vanillin using biotechnological processes. There are three approaches classified as plant-based, enzyme-based, and microorganism-based for green vanillin production. The plant-based approach uses plant tissues to synthesize vanillin via the biosynthetic pathway as secondary metabolites. However, low vanillin yield is a major limitation. The enzyme-based approach involves the use of enzymes in vanillin biosynthesis using different substrates. The microorganism-based approach uses bacteria, fungi, yeast, or engineered microbial cells in vanillin synthesis using agricultural byproducts. These agricultural byproducts are precursors such as ferulic acid, eugenol, and isoeugenol that serve as bioconversion based substrates for vanillin synthesis (2).

The inclusion of acetovanillone, a small component in the lignin-derived product that is absent from vanillin produced from guaiacol, is thought to provide lignin-based artificial vanilla flavoring a more complex taste profile than oil-based flavoring.

Natural production of vanilla

Vanilla planifolia, a vining orchid native to Mexico but now cultivated in tropical regions all over the world, is used to make natural vanillin. Natural vanillin’s biggest producer right now is in Madagascar. The orchid genus Vanilla consists of 110 species, three of which are cultivated for their flavor-related commercial value. For centuries vanilla flavor remained classified for the rest of the world since it was ascribed as a flavor of nobility by Aztecs and pre-Columbian Mayas. It was in 1519 that vanilla was exposed to the world with the Spanish invasion of the Aztecs. It was transported to Europe and subsequent development of hand pollination techniques led to its expansion to other parts of the world (1).

The green seed pods contain vanillin in the form of its -d-glucoside, however, the green pods do not have the smell or odor of vanilla after they’ve been harvested.

Once they’ve been collected, vanilla beans go through a month-long curing process to produce their flavor. The specifics vary from place to region, but the general flow is as follows:

By first blanching them in hot water, the live plant tissues’ operations are stopped. As part of this process, the pods are exposed to sunlight during the day, then covered in a cloth and placed in an airtight container at night for 1–2 weeks to allow them to sweat. These dark brown pods contain enzymes that release vanillin as the free molecule during this process.

After that, the pods are dried and seasoned for many months further to bring out their full taste. Several methods have been described for curing vanilla in days rather than months, but they have not been widely developed in the natural vanilla industry, with its focus on the production of a premium product using established methods rather than innovations that might alter the flavor profile of the product itself.

During the ripening process, the vanillin level gradually increases in the form of its glucoside, reaching a maximum at harvest (8 to 9 months post-pollination). During the curing process, the vanillin glucoside is hydrolyzed by glucosidase activity and, by the end of the curing process, most of the glucoside has been converted into vanillin (3).

Chemical synthesis of vanilla

Vanilla beans have been in short supply for a long time now. Chemical synthesis was used to make the rest. Eugenol (found in clove oil) was first synthesized in 1874–75, less than 20 years after it was initially discovered and isolated.

Until the 1920s, eugenol was used to manufacture vanillin commercially. The “brown liquor,” a byproduct of the sulfite process for manufacturing wood pulp, was later used to synthesize it. Even though it is made from waste materials, lignin is no longer popular due to environmental concerns, since guaiacol has replaced it as the primary source of vanillin in the food industry today. Vanillin may be synthesized from guaiacol in a variety of ways.

Since the 1970s, Rhodia has been using a two-step procedure in which guaiacol combines with glyoxylic acid via electrophilic aromatic substitution, which is the most important at this time. The resultant vanillylmandelic acid is subsequently transformed to vanillin by oxidative decarboxylation of 4-Hydroxy-3-methoxyphenylglyoxylic acid. However, although the vanillin produced from guaiacol (oxidation) was approved by the FDA and the EC, its use as a food additive is restricted in several countries (4).

As mentioned above, in addition to the environmental problems associated with the chemical synthesis of vanillin, the high purity of raw materials is an additional drawback, as well as a lack of substrate specificity in reactions due to the formation of concurrent by-products, which reduces the product yield and make synthesis less efficient. For this reason, in recent years, bioengineering and fermentation technology have been integrated to obtain biotechnological-derived vanillin (bio-vanillin or natural-labeled vanillin). The so-called “green production” of vanillin may go through fermentation by fungi or bacteria and through enzymatic pathways    (4).

Uses of vanilla

The most common usage of vanillin is as a flavor in sweet foods, such as cookies and cakes. Vanilla flavoring accounts for 75 percent of the market for vanillin, which is utilized in both ice cream and chocolate products, as well as confections and baked goods.

Additionally, vanillin is utilized in the fragrance business, in fragrances, and to conceal undesirable smells or tastes in pharmaceuticals, animal feed, and cleaning goods. It is also employed in the taste business, where it serves as a primary note for a variety of creamy flavor profiles, such as cream soda, as well as other desserts.

Vanillin may also be used as a general-purpose stain for thin-layer chromatography plates to help identify spots. When using this stain, you may get a variety of shades for the various components. Tannins may be seen in cells via Vanillin–HCl staining.

Furthermore, vanillin has been investigated for medical uses. Recently, bioactive properties of vanillin, such as neuroprotection, anticarcinogenic, and antioxidant are gaining attention, and vanillin and its synthetic analogues are found to regulate gene expression and exhibit biological activities (1).

Adverse effects of vanilla

A tiny percentage of migraine sufferers may be triggered by vanillin. Vanilla may cause allergy responses in certain individuals. Alternatively, they may be allergic to synthetic vanilla but not real vanilla, or the other way around, or both. Allergic reactions and migraine headaches in humans are two important vanillin overdose side effects (5). Other adverse effects such as bronchoconstriction in an asthmatic patient following oral doses of either 0.24 mg or 1 mg vanillin were observed (6).

Contact dermatitis may be triggered by vanilla orchid plants, particularly in the vanilla trade workers who come into touch with the sap. Vanillism, an allergic contact dermatitis, causes swelling and redness, as well as other symptoms in certain people.

It is possible to get mild to severe dermatitis from the sap of vanilla orchids that drips from cut stems or where the beans are picked. Workers on vanilla plantations have reported developing contact dermatitis after coming into touch with calcium oxalate crystals in the sap of the vanilla orchids. Vanilla lichen, a pseudophytodermatitis, may be produced by mites as small as a grain of rice. Occupational contact dermatitis to vanilla was reported for producers of baked goods, and contact dermatitis resulted from use of a vanilla lip salve. Dermatitis due to mechanical irritation of vanillin dust also was observed (6).

Conclusion

In this brief guide, we answered the query, “What is artificial vanilla?” and discussed what is vanilla and how it is made?

References

1. Paul, Veena, et al. A comprehensive review on vanillin: its microbial synthesis, isolation and recovery. Food Biotechnol, 2021, 35, 22-49.
2. Arya, S.S., Rookes, J.E., Cahill, D.M. et al. Vanillin: a review on the therapeutic prospects of a popular flavouring molecule. ADV TRADIT MED, 2021, 21, 1–17.
3. Khoyratty, Shahnoo, Hippolyte Kodja, and Robert Verpoorte. Vanilla flavor production methods: a review. Ind Crops Prod, 2018, 125, 433-442.
4. Martău, Gheorghe Adrian, Lavinia-Florina Călinoiu, and Dan Cristian Vodnar. “Bio-vanillin: Towards a sustainable industrial production.” Trends in Food Science & Technology 109 (2021): 579-592.https://doi.org/10.1016/j.tifs.2021.01.059
5. Cheraghi, Somaye, Mohammad A. Taher, and Hassan Karimi-Maleh. Highly sensitive square wave voltammetric sensor employing CdO/SWCNTs and room temperature ionic liquid for analysis of vanillin and folic acid in food samples. J Food Comp Anal, 2017, 62, 254-259.
6. Singletary, Keith W. Vanilla: potential health benefits. Nutr Today, 2020, 55, 186-196.