Detailed Explanation of Black Tea Evaluation Methods and Quality Assessment Points

By comparing with standard sample tea, the appearance and internal quality of finished black tea are organoleptically evaluated to determine its quality grade and level.

Congou black tea: emphasis is placed on a beautiful and well-proportioned appearance. Appearance evaluation covers factors such as strip shape, uniformity of pieces, color, and cleanliness. For strip shape, compare length, fineness or bluntness, thickness, and pekoe content; tightly rolled, upright and elegant, with tip buds, visible white pekoe, and a heavy, solid body are superior, while the opposite is inferior. For uniformity of pieces, compare evenness and the proportion of bottom-grade tea; the upper, middle, and lower grades of tea should be blended in appropriate proportions, connecting with one another, without gaps, lying flat and even, with the content of bottom-grade tea (broken tea) being moderate. For color, compare moistness versus dryness and evenness versus mixed appearance; dark moist and well-blended is superior, while dry gray and mottled is inferior. For cleanliness, compare the content of stems, fibers, flakes, dust, and non-tea inclusions. High-grade tea requires good cleanliness; tea below middle grade has varying limits on stems, fibers, flakes, and dust depending on the grade level. Non-tea inclusions are not permitted in any case. Internal quality is evaluated by liquor color, aroma, taste, and infused leaf. For liquor color, compare depth, brightness, and clarity versus turbidity. A red liquor with vivid color, a bright golden ring along the cup edge, or "cold cream down" (cream-down phenomenon) indicates good quality; red bright or red clear is next; red dull or turbid is the worst. For aroma, compare normal versus abnormal, high versus low, fresh versus stale, and tender versus mature. For taste, compare depth, strength, freshness, and coarseness versus astringency. Congou black tea emphasizes the type, intensity, freshness, and lasting quality of the aroma. Aroma that is high, sharp, fresh, and lasting is superior; taste that is mellow, rich, fresh, sweet, and refreshing is superior. Congou black tea is suitable for plain drinking, emphasizing high aroma and mellow taste.

Souchong black tea: strips that are long and loose, with thick leaf flesh and dark moist color are preferred; thin, lean, gray, and dry is inferior. For internal quality, the finest grade has a cedar-smoke aroma and a taste resembling longan soup. Infused leaf is compared for tenderness, color, and tenderness in terms of leaf texture softness or hardness and thickness or thinness. Color is compared for red vividness versus dullness and mixed appearance. Buds and leaves that are neat, even, clean, soft, thick, and with a red bright lively color are superior.

Broken black tea: evaluation of broken black tea focuses on internal quality, with appearance as secondary. Internal quality is mainly based on the liquor taste being strong, brisk, and fresh; aroma and taste are assessed by factors of concentration, strength, and freshness. Liquor taste concentration refers to the amount of water-soluble substances; after the tea liquor enters the mouth, a rich sensation on the tongue indicates high concentration and good quality, while thin and weak is inferior. Strength refers to the degree of pungency. Strength reflects the style type of broken black tea; strong and pungent is good, while mellow and mild is inferior. Freshness refers to the degree of briskness; fresh and brisk is good, while dull and stale is inferior. Precious black tea wins by its distinctive fragrant aroma and a tender but not overly strong taste; seasonal good tea is judged by its distinctive fresh, pleasant aroma and taste, not by concentration. If the aroma contains smoke, scorch, mold, sourness, or any off-odor, it is inferior tea. Liquor color is compared for redness, depth, and brightness. A bright, deep golden ring along the cup edge is preferred. After adding milk, brown-red, pink, or orange is superior; gray-white, dull, or turbid is inferior. Broken black tea requires heavy, solid granules; if the volume of 10g of broken tea exceeds 30-32ml, it is a light, low-grade tea. If there is gray dust passing through a 40-hole sieve (especially a 60-hole sieve), the grade specification is unclear. Color is compared for fresh moistness versus dry gray, and evenness versus mixed appearance. Generally, early-season tea and tender tea have a darker black color, while late-season tea and mature tea show brownish even brown-red; fresh, even, and moist is good, while gray, dry, and mottled is inferior. For broken black tea, the content of stems and fibers is generally not strictly required; especially seasonal good tea containing tender stems and fibers does not affect quality.

Quality characteristics of black tea

The traits that display the quality characteristics of black tea in color, aroma, taste, and shape. Generally, the dry tea is black, the liquor is red, and the leaf is red. Black tea includes Congou black tea, Souchong black tea, and broken black tea.

Congou black tea is blended from strip-shaped teas of varying lengths in certain proportions. The strips are tight and elegant, even, flat-lying, with good tip buds and a dark moist color; the internal quality has high aroma and mellow taste. Each type of Congou black tea has its own characteristics. For example, Keemun black tea has a dark black color with striking luster and a unique honey-like fragrance, internationally praised as "Keemun aroma." Dianhong is a large-leaf Congou black tea with plump, heavy strips covered with golden yellow bud pekoe, a fruity aroma, high fragrance, and strong taste.

Souchong black tea belongs to strip-shaped black tea, with the most famous produced in Xingcun, Chonggao County, Fujian Province, called Zhengshan Souchong. Zhengshan Souchong has long, loose strips, dark black and oily moist, with a liquor color like syrup-like deep golden red, a pleasant cedar-smoke aroma, and a longan-soup taste.

Broken black tea is divided by appearance characteristics into four types: leaf tea, broken tea, fannings tea, and dust tea. China generally produces granular broken tea; next are dust tea and fannings tea, collectively called broken black tea. Its characteristic is a finely broken appearance; due to differences in variety, processing method, and leaf type, the quality characteristics also differ.

① Different varieties have different quality characteristics. For example, large-leaf broken black tea has a plump, sturdy, heavy, solid appearance, with a moist color tending brown with black; tender tea shows golden bud pekoe, the liquor color is red deep with golden brightness, the aroma and taste are intense and strongly pungent, and the infused leaf is thick, soft, and red bright. Medium and small-leaf broken black tea has a tight, small appearance, dark moist color, red bright liquor with insufficient concentration, high aroma and fresh taste but insufficient strength, weak pungency, and the infused leaf is fairly red bright and relatively thin.

② Different processing methods have different quality characteristics. For example, traditional-process broken black tea products include leaf, broken, fannings, and dust grades; the appearance is characterized by a dark black oily moist color, the internal quality liquor taste concentration is fairly good, and freshness and strength are slightly weaker. CTC-process broken black tea products include only broken tea, dust tea, and a small amount of fannings tea; the main characteristic is that the granules of broken tea are slightly larger than those from other processing methods, approximately square, even and heavy, solid, and the color of broken, fannings, and dust tea all tends brown-red, with the liquor taste being strong, brisk, and fresh relatively comprehensively. Rotorvane-process broken black tea products have slightly poorer heaviness and solidity, good liquor taste concentration, and relatively poor freshness. Hammer mill-process broken black tea (abbreviated as LTP process) products are small, fine, even, with a dark moist color tinged with gray; the liquor taste has good freshness, strength, and pungency, concentration is acceptable, and the infused leaf consists of small leaf particles adhering into granules.

③ Different leaf types have different quality characteristics. For example, leaf tea is strip-shaped, with tender stems, and the strips are straight, upright, long, and elegant; among those made from large-leaf varieties, the strips are plump, long, and elegant with golden yellow bud pekoe, the liquor taste is mellow and rich, freshness is good, and pungency is somewhat weak. Leaf tea made from medium and small-leaf varieties has thin, long strips, a dark black color, no pekoe or little pekoe, a fresh mellow liquor taste, and lacks pungency. Broken tea is granular, tightly rolled and heavy, solid, even in thickness, without thin short strip-shaped tea or light thin fannings and dust tea, and the liquor taste is strong, brisk, and fresh relatively well. Fannings tea is in curled flake form, even in size, lighter in body, with fairly acceptable freshness in the liquor taste and slightly weaker concentration and strength. Dust tea is in sand-grain form, small, fine, and heavy, solid, without gray dust, and the liquor taste is still fairly strong but lacks freshness.