8. Binglang production in China

 

Hainan province produces 99% of areca nut produced in China and rest is produced in Yunnan, Guangdong, Guangxi, Fujian provinces. A systematic monoculture plantation of areca nut is found in Hainan province. Green immature areca nuts of size 3-5 cm long (perhaps 4-5 months’ maturity) are harvested, and individual nuts are separated from the bunch. These fresh whole areca nuts without removing the husk are processed into refined betel nuts, referred to as “Binglang”, through complex process involving boiling, flavour addition, brine addition and drying. Binglang is a refined, processed areca nut devoid of the kernel (seed). Over 95% of the harvested nuts are processed into dried betel nuts in Hainan province and transported to Hunan Province for the production of "Binglang".  

Blanching is the first step in the traditional processing of fresh betel nuts, which involves cooking in boiling water for 30–50 min followed by the drying and roasting of the nuts by using smoke generated by burning moist rubber wood. Generally, after these processes, the moisture content of the betel nut will reach about 15%. The smoked betel nuts gradually develop a dark skin due to the accumulation of smoke particles on the surfaces and hence they are commonly named smoked or black nut and exhibit a distinctive smoky flavor. Such dried nuts are transported to Hunan province for the production of "Binglang". Typically, the smoked nuts are boiled under atmospheric pressure for approximately 20 min. Food-grade sodium hydroxide, sodium bicarbonate, sodium carbonate or calcium hydroxide, are added while cooking. After cooking, the betel nuts are usually treated with an enzyme to soften the fibers and eliminate astringency. Then, betel nuts are immersed in a solution containing sugar, sodium cyclamate, licorice extract, vanillin and edible flavors and steeped for couple of days at room temperature. The moisture content of betel nuts after this step typically reaches 45%. Therefore, the nuts are roasted to reduce the water content by hot-air baking techniques and fix the sweeteners. The dried sweet nuts are soaked in proprietary solution containing various flavors and fragrances and this process usually takes 3-24 hours. To improve the visual quality of the flavored sweet nuts, the ovoid betel nuts are flattened by using hydraulic equipment, which alters their shape to become flat, loosens the fibers and creates specific patterns. these flat nuts are given a surface coating by spraying a mixture of gelatin, gum arabic, carrageenan and modified starch, in addition to sweeteners, preservatives, fragrances and flavors. After giving the surface coating, the betel nuts are transported to the high-clean area and the betel nut is cut into two pieces and then the kernel is picked out. that space is filled with a suitable amount of special brine. This filling is considered as the “soul” of the Binglang (refined betel nut) as it has a special effect on its flavor and texture. The brine formula and preparation process developed by different manufacturers are highly confidential. Typically, the brine solution consists of maltose (30~80%), food grade calcium hydroxide (10~40%), white sugar, additives (0.5~5.0%), water and natural flavorings. After brine dipping, the betel nuts are dried naturally to stabilize the moisture at about 22-24 %.  After the drying process, the refined betel nuts are packaged for sale.

References:

1. Zhu et al., (2023). Research Progress on Processing Technology of Refined Betel Nut in China: A Review, Processes, Vol. 11, 3199.

2. Chen et al., (2007). Study on the processing technique of edible areca. Food Sci. Technol. Vol. 32, pp. 57–59.

10. Health benefits conferred by the constituents of Areca nut. Part-VII (Arecoline)

 

Chewing Tambula and areca nut is an ancient custom practiced to obtain relaxation, better concentration, and euphoria. The constituents within the areca nut encompass diverse compounds, including polysaccharides, Phenolic compounds/ flavonoids, fatty acids, and alkaloids. Among these components, alkaloids stand out as the primary active constituents, and arecoline constitutes a significant proportion (0.3%−0.6 % by weight). Arecoline is found to be the most commonly used substance by humans now after alcohol, caffeine, and nicotine worldwide.

Historically, areca nut occupies an essential position in traditional Chinese medicine classics such as the Compendium of Materia Medica and Indian Ayurvedic texts such as Charaka Samhita, Susruta Samhita. Areca nut is often used to treat gastrointestinal disorders such as dysentery, bloating, constipation, liver ailments and oral hygiene. Interestingly, modern studies have shown that arecoline, the main active ingredient in areca nut, stimulates intestinal smooth muscle contraction and promotes intestinal peristalsis, thus improving intestinal health. In addition, as a psychoactive substance, arecoline demonstrated therapeutic potential for neurological disorders.

However, in 2020, the International Agency for Research on Cancer classified arecoline as 'probably carcinogenic to humans' (Group 2B carcinogen) based on compelling mechanistic evidence, listed in their comprehensive report.

In view of this, a research team headed by Prof. Xiaofei Wang from National Engineering Research Centre for Fruits and Vegetables Processing, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China did a thorough review of research work happened across the world on arecoline. Their research was focused on the multifaceted actions of arecoline on various organs, considering pharmacological and toxicological perspectives, and health functions of arecoline on vital systems, including its influence on neurotransmitter modulation, smooth muscle contraction, and the notable antiparasitic properties of arecoline. They also reviewed the research work happened on the toxic effects of arecoline on critical organ systems, encompassing factors like fibrosis, oxidative stress, immune dysfunction, and epigenetic alterations in the oral cavity, central nervous system, cardiovascular system, and digestive systems.

They found conclusive evidence on potential therapeutic effects of arecoline in improving the smooth muscle contractions in intestine, promoting intestinal peristalsis, treating indigestion and being antiparasitic in a way that paralyzes parasites. Furthermore, in the effects of arecoline on the Central Nervous System and digestive system, they found that low doses are beneficial while high doses are harmful.

They concluded their study with a remark that the research work done so far is not sufficient to understand the pharmacological and toxicological mechanisms of arecoline fully and to clarify the dosage-effect relationship and the long-term effects.  

Reference:

Wang et al.,(2024). Review of the toxic effects and health functions of arecoline on multiple organ systems, Food Innovation and Advances, Vo. 3(1), pages 31−41

9. Health benefits conferred by the constituents of Areca nut. Part-VI (Arecoline)

 

Arecoline is found to be the most important alkaloid among four major alkaloids and seven minor alkaloids found in areca nuts due to its role in modulating many physiological functions upon human consumption. Depending on the stage of maturity of areca nuts harvested, method of processing, geographical location and cultivar, its concentration can vary between 0.64 to 12.79 mg/g on dry weight basis.

In humans, depending on the dose and individual responsivity, arecoline causes enhanced alertness and learnability, enhanced mood, feeling of great pleasure, higher awakening, stimulation of the sexual desire, reduction in anxiety and promotion of calmness.

Arecoline is a very effective antiparasitic drug. Traditional Chinese Medicine uses three forms of processed areca nut (raw Arecae semen, Arecae semen tostum and Arecae semen carbonisata) for the preparation of antiparasitic drugs. Arecoline is found to be highly effective against tapeworms.

Arecoline has a wide spectrum of pharmacological effects beyond Central Nervous System such as modulation of cardiovascular, digestive and endocrine systems as well.  Like nicotine, arecoline also evokes addiction and withdrawal symptoms (upon discontinuation). Withdrawal symptoms could be mood swings, anxiety, irritability and insomnia.

The International Agency for Research on Cancer (IARC), an intergovernmental agency affiliated to WHO of the UN, published its report on the carcinogenic hazards of arecoline in 2021 (Vol. 128). About 20 experts drawn from 11 countries including India were part of the “working group”. After a thorough analysis, the working group concluded that “Arecoline is possibly carcinogenic to humans (Group 2B)”.

The working group came to a conclusion that arecoline exhibit multiple key characteristics of carcinogens in general. It alters DNA repair mechanism and causes genomic instability in experimental systems. However, the group found limited evidence for cancer in experimental animals. The group didn’t find any studies on the incidence of cancer due to the arecoline. Hence, with a greater degree of uncertainty, the working group concluded that arecoline might be a carcinogen. 

Many leading researchers are of the opinion that arecoline and related compounds have a considerable potential in medicine, with multiple positive neural effects that can be applied in neurology and psychiatry.

References:

IARC monograph published in 2021, Vol. 128.

Volgin et al. (2019). DARK Classics in Chemical Neuroscience: Arecoline. ACS Chemical Neuroscience, Vo. 10, pp. 2176-2185.

 

8. Health benefits conferred by the constituents of Areca nut. Part-V (Catechins)

 

Catechin, name was apparently derived from the word "catechu," a boiled extract/tannic juice of a Katch tree (Scientific name: Acacia catechu). This tree is called as “Kadira” in Sanskrit, “Khair” in Hindi. Kattha, a main product produced out of bark extract of Acacia catechu contains Catechins & its isomer epicatechin. As per an ancient Indian book, Jyotirnibandha written by Shivraj in AD 1524, Kattha (catechu extract) is a most important ingredient of Tambula (Betel quid) along with areca nut, betel leaf and lime. Apparently, the scientific name of Areca nut (Areca catechu) is derived due to the presence of large amount of catechin in Areca nuts. 

Catechin is one of the most abundant and important phenolic compounds found in areca nuts as well. Its concentration in areca nut depends upon the maturity of the areca nut harvested, processing method and the cultivars. The concentration can vary anywhere between 7 mg to 25 mg per gram of dried nuts.

Numerous studies involving cell-lines, animal models and in silico models have shown that Catechin/ epicatechin is a very important phytochemical. Its biological action encompasses antibacterial activity, anti-carcinogenic activity, anti-cataract activity, antifungal activity, anti-hypercholesterolemic activity, anti-inflammatory effect, anti-oxidative effect, antiproliferative activity, and antiviral activity. Though most studies relate their potential to anti-oxidative action and radical scavenging action, still the mechanism of action is not clearly understood. Recent studies shows that most of the beneficial functions of catechin/epicatechin is due to their ability to scavenge reactive oxygen species produced in the body, inhibiting transcription factors (controlling the expression of various genes in the body), and inhibition of pro-oxidant enzymes (tend to produce free-radicals in the body).

More than 18 clinical trials on the human population with different conditions have been carried out so far on the effectiveness of catechin /epicatechin. There is conclusive evidence that catechin / epicatechin are an effective and promising form of treatment of several disease conditions.

Most of the health benefits of Tea (Black & Green tea) is attributed to catechin/epicatechin & catechin gallates (gallic acid esters of catechins/epicatechins). Interestingly, areca nut contains considerable amount of catechins (7-25 mg/g) yet found little attention in scientific studies & food industries, which is rather surprising. 

References

Baranwal et al. (2022). Pharmacological Actions and Underlying Mechanisms of Catechin: A Review, Mini Reviews in Medicinal Chemistry, Vol. 22 (5), pp. 821-833(13).

7. Health benefits conferred by the constituents of Areca nut. Part-IV (Catechins)

 

Catechin is another very important phenolic substance present in areca nut in substantial quantity. Its concentration can range anywhere between 7-25 mg per gram of dry areca nut. The areca nuts of 6-7 months’ maturity were found to contain 24 mg of catechin, compared to the ripened areca nuts of  9-10 months’ maturity (8.51 mg/g) as per one Indonesian report. Interestingly, areca nuts harvested at 5 months maturity in China (Hainan province) for the production of Bing lang had only 7.2 mg per gram of dried areca nut, which is lesser than the matured areca nut.

Catechins are flavanols, which are also called proanthocyanidins or flavan-3-ols. Tea, wine and chocolates are some of the most prominent dietary suppliers of catechins to humans. Red wine, green, black and oolong teas, fruits like plum, apples, peach, strawberry and cherry, and beans and grains like broad bean, lentil and cocoa are rich in catechins. As per one study, Chocolate contributes 20% of the daily catechin intake in the Dutch population, and tea contributes 55%. Mediterranean diets, which are rich in wines and fresh fruits and vegetables, were found high in catechins. Mediterranean diet which is considered as one of the healthiest is found to provide about 100 mg of catechins and procyanidins per person per day.  Total catechin contents of green and black tea are about 420 and 250 mg/L, respectively.  About 12.5 grams of areca nut (Chali or white supari) or about 4 grams of red supari (Kempadike) can provide the equivalent amount of catechin to humans. 

Catechin are found to exhibit physiological effects, including antibacterial, antifungal, antiviral, antioxidative, and antitumor activities. Recent studies have suggested that catechins also promote oral health and contribute to a reduced risk for some systemic disease.

The oral cavity of humans contains more than hundred species of microbes. An increase in the number of these microorganisms like high pathogenic potential species, such as cariogenic and periodontopathic bacteria, and the change of microbial biota may result in, not only oral infection, but also systemic diseases, such as infective endocarditis and aspiration pneumonia. It is very important to control the growth of these microorganisms and its biota just after oral cleaning in order to suppress disease onset. Numerous studies have proved that catechin formulations inhibited the growth of the Actinomyces, periodontopathic bacteria and Candida strains tested, but did not inhibit that of the oral Streptococci that are important in the normal oral flora. Thus, it was clear that catechins can improve the oral hygiene and deter the onset of oral infection, and systemic diseases, such as infective endocarditis and aspiration pneumonia.

Perhaps, the ancient Indian medical practitioners were aware of the importance of catechin present in areca nut and hence had prescribed chewing of Tambula (Betel quid) after every meal.  

References

Tamura & Ochiai (2012) Exploring the possible applications of catechin (gel) for oral care of the elderly and disabled individuals, Japanese Dental Science Review, Vol. 48, pp. 126—134

Yusuf Yilmaz (2006). Novel uses of catechins in foods. Trends in Food Science & Technology, Vol. 17, pp. 64–71

Sari et al., (2020). Distinct phenolic, alkaloid and antioxidant profile in betel quid from four regions of Indonesia, Scientific Reports, Vol. 10 : 16254

Song et al., (2022). UHPLC-MS/MS identification, quantification of flavonoid compounds from Areca catechu L. extracts and in vitro evaluation of antioxidant and key enzyme inhibition properties involved in hyperglycemia and hypertension. Industrial Crops & Products. Vol. 189, pp. 115787.