Centuries ago, Tea was a cherished guest at British tables, but its high price led unscrupulous traders to collect used tea leaves, re-dye them with sheep dung and chemical dyes, and resell them—a revelation that shocked even the royal family.
Even as outsiders with little knowledge of tea, the British devised such malicious and cunning methods to counterfeit tea. In the domestic market, where the six major tea categories are most popular and thus most susceptible to counterfeiting, the tricks employed by fraudsters are even more varied.
This article aims to expose the common counterfeiting techniques used in China's six major tea categories.
Green Tea: Talc for Shine
Harm Index: ★★★★★
Identification Difficulty: ★★☆☆☆
On June 27, 2005, the Qimen County Industrial and Commercial Bureau uncovered a case involving talc adulteration in green tea. On January 18, 2011, the Songxi Industrial and Commercial Bureau seized 20 tons of green tea illegally mixed with talc. These cases are not isolated incidents; adding talc to green tea has become an unspoken rule among some tea factories. The danger posed by talc to human health is far greater than one might imagine.
Talc, odorless and tasteless, not only increases the weight of green tea but also masks the darkened leaves, giving substandard tea an attractive appearance that rivals premium teas priced in the tens of thousands of yuan. However, talc is a chemical substance that can cause mouth ulcers when ingested and is closely linked to asbestos, a potent carcinogen. It was listed as a Group 3 carcinogen by the World Health Organization in 2025.
The good news is that this extremely harmful counterfeit tea can be easily distinguished from genuine tea. After brewing, if the tea soup appears abnormally cloudy and remains so, there is a risk of talc contamination.
Green Tea: Dyeing with Pigments
Harm Index: ★★★★★
Identification Difficulty: ★★★☆☆
As the most consumed type of tea, green tea is often targeted by counterfeiters who add industrial pigments to low-quality green tea. The purpose of the fixation process in green tea is to destroy polyphenol oxidase, preventing oxidation and preserving the original color. However, after fixation, some average-quality green teas may lose their original color, making them less valuable. To increase profits, dishonest merchants resort to dyeing with pigments.
To reduce costs, illegal traders commonly use chromium green, a notorious industrial chemical dye. When ingested, it can cause irreversible and permanent damage to organs and nerves. Due to its extreme nature and severe harm, the State Administration for Market Regulation issued a notice on May 13, 2025, titled “Determination of Chromium Green in Tea,” to crack down on dyed teas on the market.
One straightforward method to identify pigment-dyed teas involves observing the tea down; if it is green instead of white, the tea is likely fake. Another method involves rubbing the tea between wet fingers and checking for any discoloration. Alternatively, brewing the tea can reveal inconsistencies in the color of the tea soup. For a more scientific approach, refer to the national standard “Determination of Chromium Green (Chromium Green) in Tea BJS202510.”
Oolong Tea: Flavor Enhancers
Harm Index: ★★★★☆
Identification Difficulty: ★★★☆☆
Anxi Tieguanyin, known for its floral and fruity aroma, attracts many oolong tea enthusiasts willing to pay top dollar for a high-quality brew. This is where flavor-enhanced teas, aimed at duping wealthy consumers, emerge. While there are various types of flavor enhancers, those added to tea typically produce an unnatural, concentrated aroma. Some unscrupulous sellers go further, placing tea in a room filled with volatile flavor enhancers to take advantage of the tea's strong absorbency. This method makes detection difficult.
To identify flavor-enhanced teas, one simple method is to sniff repeatedly. Genuine teas have a natural aroma, while flavor-enhanced teas will seem forced and fade quickly. Another method involves brewing the tea; genuine teas require hot water above 80°C to release their aroma, whereas most flavor-enhanced teas will reveal themselves with lukewarm water around 40°C. Flavor-enhanced teas often result in a cloudy tea soup with a layer of oil floating on the surface, and their aroma does not last beyond three infusions.
Black Tea and Yellow Tea: Sugar Processing for Sweetness
Harm Index: ★★☆☆☆
Identification Difficulty: ★★★☆☆
For many tea enthusiasts, the appeal of tea lies in its bitter-sweet transition. However, unscrupulous sellers have developed a sugar-processing technique to enhance sweetness, commonly seen in black and yellow teas. After sugar processing, inferior teas exhibit excellent aftertaste and improved appearance. Unlike the other two methods, sugar processing withstands brewing and tasting, leading to an increase in sugar-processed teas in recent years.
To identify sugar-processed teas, simply handle the tea. Due to the layer of sugar, the tea will be very brittle and break easily. Alternatively, taste a dry tea leaf; genuine teas do not have a sweet taste until brewed. However, sellers of sugar-processed teas usually prevent customers from handling the product, necessitating another method—multiple infusions. Sugar-processed teas lose their aftertaste after the third infusion, unlike genuine teas which maintain their quality throughout multiple infusions.
White Tea: Forced Aging through Fermentation
Harm Index: ★★★★★
Identification Difficulty: ★★★★☆
In the world of white tea, there is a saying: “one year as tea, three years as medicine, seven years as treasure.” This attribute has fueled the market for aged white tea. One of the most dangerous counterfeiting techniques involves using fermentation to artificially age white tea. This method, typically reserved for Pu'er ripe tea, can be applied to white tea to create an artificially aged product. However, when used on white tea, it destroys the beneficial substances within the leaves and causes harmful substances to leach out.
White Tea: Artificial Aging through Roasting
Harm Index: ★★★★☆
Identification Difficulty: ★★★★☆
The appearance and color of white tea provide the most direct indication of its age, which is often the primary criterion for determining its vintage. However, roasting can mislead such assessments. High-temperature roasting can severely damage the active enzymes and other beneficial substances in the tea, rendering it incapable of further aging. Despite this, roasted teas have a distinct smoky flavor, making them relatively easy to identify.
For blended teas with old appearances and new interiors, inspect the leaf base; genuine aged white teas have uniformly natural bases, while artificially aged ones have more variegated colors. For artificially kneaded teas, examine the tea soup; genuine aged white teas are not stir-f