Vanilla bean, is gotten from two major plants of the Orchidaceae family, Vanilla planifolia and Vanilla tahitensis. They are the two main source of vanilla extract, one of the most desired flavoring agent in food, perfumes, and also pharmaceutical products. The vanilla flavor was first used by the Aztec people in Mexico to flavor cocoa. It is the only orchid that has economic value as an edible crop.
The name is derived from the Spanish word, “vaina pequeña” meaning “Little pod”. Vanilla is the second most expensive spice behind saffron. Other expensive spices include green cardamom, nutmeg, black pepper, cloves, and turmeric.
The orchid, Vanilla planifolia or Vanilla fragrans is the most important plant that yields the vanilla extract, which is the dried and cured fruits (pods). Vanilla grows in the tropical forests of Mexico, Central and northern South America. Indonesia and Madagascar are now major producers.
Vanilla tahitensis and Vanilla pompona are the other species that are used to produce vanilla. Vanilla pompona has lesser quality, and so is used mostly in fragrance making. V. planifolia and V. tahitensis have better aroma and flavor.
The vanilla plant is an evergreen climbing vine that can grow up to 15 m in length. It has a thick stem and greenish to yellow flowers. It has dark green, bright, opposite, flat, oblong and spiky leaves.
Fruits are long, blackish brown, cylindrical, thin pods with thousands of tiny, black seeds. As it matures, it becomes black, and gives off a strong aroma.
The inflorescence involves cream-colored, pale yellow or greenish funnel-shaped flowers. Vanilla has a fleshy aerial root that helps it to climb trees. Since the plant does not tolerate salt, it rarely grows in costal areas.
Other names of vanilla includes vanilla orchid, or flat-leaved vanilla (English), vainilla (Spanish), vanilovník plocholistý (Czech), sisbik-k’aax (Maya), vainilla (Portuguese), gewürzvanille (German), vanilje (Danish), and vanilla (French).
Vanilla is one of the most desirable flavoring agent due to the sweet and soft aroma. It is used to flavor food, confectionery, ice cream, yogurt, cookies, brownies, milk products, liqueur, and custard-based sauces.
In traditional medicine, it has been used as an aphrodisiac, antimicrobial agent, to relieve fever, spasm, and gastrointestinal complaints. It is also used in spasms, dysmenorrhea, blood clot treatment.
The fresh green pod of vanilla does not give the pleasant aroma associated with vanilla. It is after the curing process, which involves four stages such as killing, sweating, drying, and conditioning.
Vanillin, the major compound responsible for the flavor and aroma in the vanilla plant, also has medicinal effects. During drying, vanillin is degraded in vanillosides. Vanillin is a white solid that oxidizes on exposure to air.
It can be of natural, synthetic or biotechnological source. According to the source, it could be a natural or artificial flavor. Only the natural and biotechnologically produced vanillin, are used as food-grade additives.
- Essential oils: vanillin, cis-vitispiran, piperonal, salicylates, vanillyl alcohol, and cinnamic acid esters.
- Alcohols: pentanol, undecanol, cresol.
- Acids: acetic acid, anisic acid, benzoic acid, salicylic acid, pentanoic acid
- Other aromatic substances: nonanal, guaiacol, dodecanal, creosol, decane, pentanal, hexanal, heptanal.
- Tannins, resins, amino acids
Vanilla extract contains 52.6 g of water, 0.06 g of proteins, 0.06 g of fats, 12.6 g of carbohydrates, 12.6 g of sugars, and 288 kcal of energy.
- Minerals: Potassium (148 mg), calcium, magnesium, phosphorus, sodium, zinc, copper, iron.
- Vitamins: Thiamine, riboflavin, niacin, pantothenic acid, vitamin B-6
Health Benefits of Vanilla Extract and Essential Oils
Vanilla have active compounds with antioxidant, wound healing, antimicrobial, neuroprotective, anticancer, anti-inflammatory, and anti-sickling properties.
The extract of Vanilla planifolia has antimicrobial activities against Staphylococcus aureus, Streptococcus mutans, and Enterococcus. Vanillin also inhibits spoilage microbes such as Pantoea agglomerans, Aeromonas enteropelogenes, Micrococcus lylae and Sphingobacterium spiritovorun (Ngarmsak et al. 2006).
Studies suggest that vanillin at sub-inhibitory doses modulate the activities of antibiotics used to treat Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli (Bezerra et al. 2017; Brochado et al. 2018)
Vanillin decrease Alternaria strains growth. RNA-seq of o-vanillin and o-ethyl vanillin inhibited the grwoth of C. neoformans, the fungus that cause cryoptococcal meningitis.
Sickle cell anemia:
In a study by Abraham et al. in 1991 using vanillin as a compound to treat sickle cell disease (SCD), vanillin exhibited a dose-dependent inhibition of deoxygenation (HbA) induced sickling and sickle haemoglobin (HbS) polymer formation.
Also, o-vanillin affected the membrane permeability of red blood cells, and reduced the complications of sickle cell disease(Hannemann et al. 2014). Vanillin derivatives also showed more anti-sickling activity when compared to vanillin.
In animal studies, vanillin improves motor coordination, learning-memory, locomotory and biochemical impairments (Gupta and Sharma 2014). It also prevents neuronal cell damage in the hippocampal CA1 region (Kim et al. 2007). It could be a potential source of medication for neurodegenerative diseases such as Parkinson’s disease (PD), Alzheimer’s disease, and Huntington’s disease.
This neuroprotective effect may be as a result of the antioxidant effect of vanillin and vanillic acids, which helps to scavenge free radical, reduce lipid peroxidation, apoptosis, and Fe2+-induced brain tissue damage.
Vanillin has antioxidant, antitumor, antimutagenic, anti-Invasive, antimetastatic, and antiangiogenic activities. Vanillin, and its derivatives, prevent DNA damage, proliferation of colon cancer cells, and increase apoptosis of cancer cells.
A vanillin derivative exhibited a strong radio-protective activity against a radiation-induced intestinal injury in mice (Li et al. 2020). Also, studies by Naz et al. 2018, reported that vanillin cause apoptosis in human hepatic carcinoma and neuroblastoma cells. Other cancer forms such as human ovarian carcinoma, human cervical carcinoma HeLa cells, human ovarian carcinoma, and human colorectal carcinoma have been studied.
Vanillin inhibit nitric oxide in the lipopolysaccharide activated (LPA) RAW264.7 macrophages (Lim et al. 2008)
Also, vanillin reduced the expression and production of proinflammatory mediators, such as IL-8, IL-6, and TNF-α. It also reduced iNOS and COX-2 gene expression, and NO production. The results suggest vanillin could be potentially used in oral health products for inflammatory periodontal disease (Erica Costantini et al., 2021).
Vanillin showed a strong radical-scavenging activity in the ABTSþ-scavenging assay. Ethyl vanillin, vanillin, vanillyl alcohol and vanillic acid are the antioxidant compounds in the plant.
The antioxidant property could be useful in keeping the quality of complex foods containing polyunsaturated fatty acids.
Vanillin can be a natural crosslinker to fabricate chitosan hydrogel for wound healing. Rat skin treated with chitosan-vanillin membrane experienced wound healing, angiogenic stimulus, collagen deposition, re-epithelialization, and reduced levels of IL-1β and TNF-α, and increased IL-10 and gene expression of TGF-β and VEGF (de Aragão Tavares et al. 2018).
Vanillin aromatherapy significantly corrected stress-induced changes in brain levels of glutathione, nitric oxide, and serotonin. It increased serotonin and dopamine levels in the brain.
In another animal studies, the exposure to the aroma of vanilla also decreased depression, probably by effect on the olfactory pathway.
Blood glucose control and lipids:
Vanillin and vanillic acid, when administered to mice fed with high-glucose/lipid diet, significantly decreased the blood glucose, triglyceride (TG), and total cholesterol levels. It also increased the blood high-density lipoprotein.
In mice administered with vanillic acid, there was less white adipose tissue, lower body weights and decreased liver steatosis. There was also increased mitochondria and thermogenesis-related activity in the brown adipose tissue.
Blood pressure lowering:
In studies with rats induced with hypertension using Nω-nitro-L-arginine methyl ester hydrochloride, vanillic acid caused a lowering of the blood pressure, decrease in oxidative stress, and increase in antioxidant enzymes. The blood lipid profiles, left ventricular function and aortic nitric oxide metabolism were improved (Kumar S, et al., 2011).
Vanillin and vanillic acid may interact with medications:
- Antidiabetic drugs: It may show additive effect with 2,4-thiozoladinedione, but not metformin.
- It interacts with drug-metabolizing enzymes CYP2E1 and CYP1A2144 and reverse multidrug resistance via inhibition of P-glycoprotein.
- Vanillin inhibits non-enzymatic glycation of albumin.
Vanilla is safe to ingest by mouth, but may cause side effects such as headache, and insomnia. Skin contact can result in irritation, inflammation, swelling. Contact dermatitis can result from the use of vanilla lip salve.
Vanilla has also been adulterated with tonga bean extract, which contains a chemical called coumarin. Coumarins are banned in food products. An isolated case of an asthmatic patient who witnessed bronchoconstriction after ingesting 0.24 mg or 1 mg vanillin was recorded.
Both oral and intraperitoneal administration of vanillin to rats, even at a concentration as high as 300 mg/kg, did not result in any toxic effect on organs such as the kidney, liver, and blood cells.