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# Overview and facts about green tea Green tea, derived from the *Camellia sinensis* plant, is a globally popular beverage known for its health benefits and diverse varieties [4](#page=4). ### 1.1 Origins and plant varieties Green tea originates from the tea plant, *Camellia sinensis* (L.) O. Kuntze. This plant was first discovered accidentally in China by Emperor Shen Nung. There are two primary varieties of *C. sinensis* [4](#page=4): * *Camellia sinensis sinensis* [4](#page=4). * *Camellia sinensis assamica* [4](#page=4). ### 1.2 Production and characteristics Green tea is produced from the small, fresh young leaves and buds of the tea plant. The processing is rapid and crucially, it does not undergo fermentation. This non-fermented nature contributes to its unique properties [4](#page=4). Green tea is recognized as a primary source of catechins and possesses medicinal, antioxidative, and antimicrobial properties [4](#page=4). > **Tip:** The absence of fermentation is a key distinguishing factor that defines green tea and preserves its beneficial compounds [4](#page=4). ### 1.3 Classification and taste The classification of green teas is based on several factors, including: * The color of the finished leaves [4](#page=4). * The color of the tea liquor [4](#page=4). * The percentage of oxidation during processing [4](#page=4). The taste of green tea is influenced by various elements, such as the chosen clone, the time of plucking, the maturity of the shoot, and the cultivation method employed [4](#page=4). ### 1.4 Types of green tea Different types of green teas are found globally, particularly in China and Japan [5](#page=5). > **Example:** Gunpowder is a well-known Chinese green tea characterized by its tiny pellet form. Sencha, a Japanese green tea, is typically more expensive and offers a delicate sweetness [5](#page=5). ### 1.5 Export and consumption facts * The first recorded export of green tea from India to Japan occurred in the 17th century [5](#page=5). * Currently, China is the world's largest producer of tea, followed by Sri Lanka and India [5](#page=5). * Tea is the most widely consumed beverage globally, ranking second only to water in terms of consumption [5](#page=5). * Green teas account for approximately 20-22% of all tea consumed worldwide [5](#page=5). ### 1.6 Visual and taste characteristics of brewed green tea Brewed green tea typically exhibits a green, yellow, or light brown color. Most green teas are quite light in color and possess a mildly astringent taste [5](#page=5). --- # Green tea processing and equipment Green tea processing involves a series of steps designed to prevent oxidation, preserving the leaf's natural green color and fresh flavor, utilizing specific equipment at each stage. ### 2.1 Overview of green tea processing steps Green tea production focuses on minimizing enzymatic oxidation after plucking. The key stages include plucking, withering, first drying, initial rolling, fixing, final rolling, and final drying, which may also include shaping for aesthetic purposes. The primary objective of fixing is to halt enzymatic activity and retain the green color [7](#page=7) [8](#page=8) [9](#page=9). ### 2.2 Detailed processing steps and equipment #### 2.2.1 Plucking Plucking involves selecting tender and uniform tea leaves, typically the buds with two leaves or the shoot with three leaves. The primary equipment used for this stage is a tea plucking machine [7](#page=7). #### 2.2.2 Withering Withering aims to reduce the humidity content of the leaves to approximately 30% over a period of 4 to 12 hours. This process makes the leaves pliable for subsequent steps. Traditionally, this is achieved through an air-blown method. The equipment used includes tea leaves withering machines or troughs fitted with fans to deliver the required airflow. These fans can be integrated into a bulked drier room to draw in hot or cool air as needed [35](#page=35) [7](#page=7). #### 2.2.3 First drying The first drying stage reduces the moisture content by about 50%. This can be performed by rotating the leaves in a metal drum for approximately 30 minutes using warm air at 55℃. Other methods include hot air drying, vacuum drying, or microwave drying. The equipment for this stage is a tea dryer machine [8](#page=8). #### 2.2.4 Initial rolling Initial rolling involves twisting and crushing the leaves to break down cell walls, releasing natural juices and enzymes, which aids in subsequent fermentation if applicable to other tea types. This process is performed for about 10 minutes under varying pressure. The equipment used is a tea rolling machine. This step also aims to release natural oils that contribute to flavor. Historically, hand-rolling was practiced for higher quality tea grades [36](#page=36) [8](#page=8). #### 2.2.5 Fixing Fixing is a crucial step to stop enzymatic activities and prevent fermentation, thereby retaining the green color of the leaves. It can be accomplished through pan-firing (Chinese style) at approximately 180℃ or steaming (Japanese style) at 100℃, with the process taking up to 2 minutes. The equipment used is a tea fixation machine. This heating also stabilizes the leaves and locks in flavor [38](#page=38) [8](#page=8). > **Tip:** Fixing is the primary process that differentiates green tea from other types, as it halts the oxidation that turns leaves brown [33](#page=33). #### 2.2.6 Final rolling In the final rolling stage, leaves are placed between two rotating metal plates and rotated for 15 minutes. This further shapes the leaves. The equipment utilized is a tea rolling machine [9](#page=9). #### 2.2.7 Final drying Final drying removes any residual moisture, creating a shelf-stable leaf and preventing further degradation. This is typically done by keeping the leaves in contact with hot air for 30 minutes. The equipment employed is a tea drying machine. This stage helps to stop oxidation and preserve the green color [33](#page=33) [38](#page=38) [9](#page=9). #### 2.2.8 Shaping Shaping involves polishing and shaping the leaves by pressing them against a hot plate. This results in very flat, glowing leaves for aesthetic appeal. The equipment used is a tea shaping machine [9](#page=9). ### 2.3 Related processing steps (for context) While not exclusive to green tea, other processing steps are relevant to tea production in general and use specific equipment. #### 2.3.1 Bruising Bruising, akin to rolling, involves twisting and crushing leaves to break down cell walls and release juices and enzymes, facilitating the next steps [33](#page=33) [36](#page=36). #### 2.3.2 Fermentation Fermentation, also known as oxidation, is where enzymatic reactions turn leaves brown. This process is crucial for developing characteristic flavors. For teas that undergo fermentation (not green tea), it occurs in a cool, humid atmosphere on trays, typically between 15-25℃, taking 1 to 4 hours. The longer the fermentation, the stronger the flavor and darker the leaves become. Equipment includes fermentation machines [33](#page=33) [37](#page=37). #### 2.3.3 Firing equipment Firing is used in other tea types after fermentation to dry leaves and retard further enzymatic processes. Leaves move through hot air chambers to stabilize them and lock in flavor. Temperatures can range from 90℃ (in) to 50℃ (emergent) for 18-20 minutes [38](#page=38). #### 2.3.4 Grading equipment Grading separates leaves based on size, with examples including orange pekoe, pekoe, souchong, broken variants, and fanning/dust for tea bags [39](#page=39). #### 2.3.5 Tea blending Blending combines different teas to create a final product, often to mask inconsistencies and ensure reliability in taste. This can be done manually or mechanically using large rotating cylinders [40](#page=40). ### 2.4 Types of tea processing comparison Green tea is distinct in its processing, primarily involving steaming or pan-firing to kill enzymes responsible for fermentation, resulting in soft, pliable leaves. Unlike other teas, it is not deeply processed or fermented. White tea is simply steamed and dried. Oolong tea is partially fermented, offering a flavor profile between green and black teas. Black tea is not steamed and undergoes wilting and fermentation, causing leaves to turn brown and lose their green color [41](#page=41) [42](#page=42). --- # Technology in green tea production This section explores advanced drying technologies and modern processing innovations revolutionizing green tea production. ### 3.1 Drying technologies for green tea The drying stage is critical in green tea production, aiming to reduce moisture content to approximately 2% while preserving quality. Several advanced technologies are employed to achieve this efficiently and effectively [12](#page=12). #### 3.1.1 Fluidized bed dryer A fluidized bed dryer operates on the principle of fluidization, where air is passed through a bed of granular tea leaves under controlled conditions, causing them to float in the air stream. This process leads to uniform drying due to improved thermal contact between the tea leaves and the air, resulting in a higher drying rate [10](#page=10). ##### Advantages of fluidized bed dryers: * Higher efficiency and lower cost due to uniform drying and improved thermal contact [10](#page=10). * Leads to better quality of dried green tea leaves [10](#page=10). * Facilitates better flow of tea leaves, allowing for continuous feeding and discharge [10](#page=10). ##### Key controlled parameters: * Velocity of air [10](#page=10). * Particle size of tea leaves [10](#page=10). * Temperature [10](#page=10). * Retention time [10](#page=10). #### 3.1.2 Microwave dryer Microwave dryers utilize microwave energy for rapid internal heating of tea leaves. This method does not require direct contact between the energy source and the material, and the heating is volumetric, rapid, and highly specific [11](#page=11). ##### Mechanism of microwave heating: The process is based on the agitation of polar molecules within the tea leaves. These molecules oscillate under the influence of an oscillating electric and magnetic field, which are transported as electromagnetic waves within a frequency range of 0.3 GHz to 300 GHz. This oscillation causes 'molecular friction' within the material, leading to heating [11](#page=11). ##### Advantages of microwave dryers: * Fast internal heating [11](#page=11). * No contact required between energy source and materials [11](#page=11). * Heating is volumetric, rapid, and highly specific [11](#page=11). #### 3.1.3 Infrared dryer Infrared dryers use controlled heat emitted as infrared radiation to dry tea leaves. This method offers faster drying times and a more controlled process due to rapid response times [12](#page=12). ##### Types of infrared radiation used: * Near infrared [12](#page=12). * Short wavelength infrared [12](#page=12). * Mid wave infrared [12](#page=12). * Long wave infrared [12](#page=12). * Far wave infrared [12](#page=12). ##### Advantages of infrared dryers: * Faster drying time of tea leaves [12](#page=12). * Easy and rapid process control due to faster response times [12](#page=12). * No direct contact with tea materials [12](#page=12). * Possibility of selective heating [12](#page=12). * Better color and flavor retention in the tea leaves [12](#page=12). * The process typically takes about 15-20 minutes to reduce moisture content to 2% [12](#page=12). > **Tip:** While advanced drying technologies offer significant advantages, careful parameter control (velocity, temperature, time) is crucial to maintain the delicate flavor profile of green tea [10](#page=10) [12](#page=12). ### 3.2 Modern tea processing innovations Technology has transformed tea processing from traditional labor-intensive methods to mechanized, high-volume procedures, making the process more intelligent and efficient [45](#page=45). #### 3.2.1 Tea roller Modern tea rollers are designed to tightly wrap tea leaves in cloth for pressing and rolling. These machines were developed to improve the efficiency of a traditionally skilled task [46](#page=46). ##### Benefits of modern tea rollers: * Significantly reduces the number of times leaves need to be rolled in cloth [46](#page=46). * Reduces labor and cost [46](#page=46). * Increases the volume of production [46](#page=46). #### 3.2.2 Stem removal machines Stem removal machines represent a more recent innovation in tea processing. These machines are equipped with fine brushes and small blades that efficiently separate protruding stems from rolled tea leaves [47](#page=47). ##### Components and operation: The process typically involves two separate pieces of equipment: 1. A system that feeds tea leaves onto a conveyor belt into a funnel [47](#page=47). 2. The stem-removing machine itself, which processes the leaves [47](#page=47). > **Example:** The introduction of a mechanized tea roller means a single operator can achieve the rolling output that previously required multiple individuals, dramatically improving factory throughput and reducing operational costs [46](#page=46). --- # Packaging, labeling, transportation, and food law This section details the critical aspects of packaging, labeling, transportation, and food law as they apply to tea, ensuring quality preservation and consumer information. ### 4.1 Packaging Packaging for tea serves multiple purposes, including protection, preservation of freshness, and branding, especially for premium or exotic varieties. The choice of packaging material and design is crucial to maintain the delicate nature of tea leaves and prevent deterioration caused by oxygen and moisture exposure [49](#page=49) [50](#page=50). #### 4.1.1 Packaging materials and considerations Key considerations when selecting quality tea packaging include: * **Protection**: Essential to shield tea from external elements [50](#page=50). * **Material**: Materials should preserve tea freshness for extended periods. Examples of suitable materials include cellophane, paper, polyethylene, polypropylene, polyvinylidene chloride, vinylon, and aluminum foils. These are evaluated based on their dampproofness, nitrogen gas permeability, and odor permeability [13](#page=13) [50](#page=50). * **Branding and Colour**: Packaging plays a role in brand identity and market differentiation [50](#page=50). * **Airtight Closure**: Tight closures are vital to prevent deterioration from oxygen and moisture [50](#page=50). Various materials are suitable for presenting teas: * **Tea bags**: Offer convenience and are often made from paper fiber and other biodegradable materials, minimizing mess [52](#page=52). * **Barrier bags**: Provide multilayered protection against UV rays [52](#page=52). * **Metal containers**: Exhibit high durability and impact resistance, and their shiny appearance can appeal to consumers seeking sophistication [52](#page=52). * **Glass containers**: Convey a clean, artistic, and classy look, especially with eye-catching shapes or elegant designs [52](#page=52). * **Cardboard**: Is lightweight and easy to carry, suggesting ecological efficiency and finesse [52](#page=52). * **Light plywood chests**: Lined with aluminum foil and parchment paper are used for more traditional or premium packaging [13](#page=13). * **Tinplate containers**: Wrapped with bast mats are also a traditional option [13](#page=13). * **Paper bags, tea cans, or plastic films**: Are common for commercial packaging [13](#page=13). > **Tip:** For luxury foodstuffs or exotic teas with psychoactive ingredients and mood-stimulating tastes, packaging must be as intriguing as the taste to connect with an affluent target market willing to pay more for higher quality [49](#page=49). ### 4.2 Labeling claims The primary objective of labeling claims is to factually and informatively describe a food product's qualities, assisting consumers in making better food choices [54](#page=54). #### 4.2.1 Types of labeling claims Labeling claims can be categorized as follows: * **Product quality claim**: Used to attract specific consumer segments, such as "Exclusive" for high-end consumers [14](#page=14). * **Product sensory claim**: Describes the sensorial properties of the product. Examples include "Light taste and aroma" "Aromatic," and "Sweet, Buttery Taste" [14](#page=14) [15](#page=15). * **Product content claim**: Informs consumers about the product's composition or absence of certain ingredients. Examples include "Decaffeinated" for consumers with caffeine sensitivity and "Pure" to indicate no added materials [14](#page=14) [15](#page=15). * **Product function claim**: Informs about the intended function of nutrients within the tea, such as "Supports Vitality" [15](#page=15). #### 4.2.2 Essential information on labels Labels must include comprehensive information for the consumer: * **Ingredients**: All added substances must be listed in order of quantity from largest to smallest, using INCI names [55](#page=55). * **Instructions for Use**: An instruction manual should be included for proper use, unless otherwise justified [55](#page=55). * **Responsible Person (RP) Name and Address**: Must correspond to the product's origin [55](#page=55). * **Weight and Batch Number**: Must be clearly indicated on the product [55](#page=55). * **Brand Identity**: Labeling serves as the foundation for brand identity and differentiation [55](#page=55). #### 4.2.3 Specific labeling requirements for tea Under the Malaysian Food Regulations 1985, specific labeling provisions exist: * If tea, tea dust, tea extract, or scented tea originates exclusively from one location, the name of that location can be stated on the label [20](#page=20). * The word "tea" is permitted on a label only if the package contents and label comply with the regulations [20](#page=20). * For tea extract, instant tea, or soluble tea, the words "tea extract," "instant tea," or "soluble tea" must be displayed in larger letters than any other words on the label, except for the brand name [20](#page=20). ### 4.3 Transportation Tea transportation requires specific conditions to maintain its quality, as tea is sensitive to temperature, humidity, moisture, and ventilation [57](#page=57). #### 4.3.1 Transportation modes and conditions Common modes of transport include ships, trucks, railroads, and aircraft. Regardless of the mode, container cargo conditions must ensure the product remains [16](#page=16): * **Watertight** [16](#page=16) [58](#page=58). * **Not contaminated** in any way [16](#page=16) [58](#page=58). * Stored away from heat sources to prevent desiccation and drying [16](#page=16) [58](#page=58). * Maintained at a temperature range of 5-25 ℃ [16](#page=16) [58](#page=58). * Maintained at a relative humidity of 50-60% [16](#page=16). * Kept in cool, dry, and well-ventilated conditions [16](#page=16) [58](#page=58). * Protected from moisture, as high humidity can lead to mold development [16](#page=16) [57](#page=57) [59](#page=59). > **Tip:** Containers whose floors release foreign odors, are contaminated by substances, or are too damp must be rejected [58](#page=58). #### 4.3.2 Cargo handling practices Effective cargo handling is crucial: * **No hooks**: Hooks should not be used as they can tear or puncture packaging, leading to loss of contents [59](#page=59). * **Pallets**: Handling on pallets is highly effective as it reduces the risk of breakage by allowing chests to be stacked uniformly [16](#page=16) [59](#page=59). * **Filling spaces**: Spaces between packages should be filled to prevent slippage or tipping [59](#page=59). * **Wood moisture content**: The wood of chests should have a water content of 10% to a maximum of 12%, corresponding to an equilibrium moisture content of 60-70% [59](#page=59). ### 4.4 Food law Food laws provide standards and regulations to ensure the safety, quality, and appropriate labeling of food products. #### 4.4.1 Malaysian Food Regulations 1985 concerning tea The Malaysian Food Regulations 1985, specifically Regulation No. 260, defines and sets standards for tea. Key provisions include [19](#page=19): * **Definition of Tea**: Tea is defined as the product of steaming, drying, or firing (or a combination thereof) of fermented, semi-fermented, or non-fermented leaves, bush, and tender stems of one or more varieties of *Camellia* [19](#page=19) [56](#page=56). * **Quality Standards**: * Tea shall not yield more than 7% of total ash, with at least half of this ash being soluble in boiling water [19](#page=19) [56](#page=56). * Tea shall yield not less than 30% of water-soluble extract [19](#page=19) [56](#page=56). * Tea must not contain spurious, exhausted, decayed, or moldy leaves or stalks, nor any foreign matter [19](#page=19) [56](#page=56). * **Coloring Substances**: Tea shall not contain any coloring substances, whether permitted or not under the regulations [19](#page=19) [56](#page=56). Other related regulations include those for tea dust, tea fanning, tea sifting tea extract, instant tea, soluble tea scented tea and tea mix [19](#page=19) [20](#page=20). #### 4.4.2 Standards for tea extract, instant tea, or soluble tea Regulation No. 262 sets specific standards for these products: * **Definition**: They are defined as dried products made exclusively by aqueous extraction of tea [20](#page=20). * **Compositional Standards**: * Shall not contain more than 20% of total ash [20](#page=20). * Shall not contain more than 6% of water [20](#page=20). * Shall contain not less than 4% of caffeine [20](#page=20). * Shall contain not less than 7% of tannin [20](#page=20). * **Performance Standard**: Must dissolve in boiling water within 30 seconds with moderate stirring, and the infusion must possess the color, taste, and flavor of freshly brewed tea [20](#page=20). --- # Shelf life and cost estimation for tea This section provides an overview of the shelf life for various tea types and details the components involved in estimating the cost of tea production. ### 5.1 Shelf life of tea The shelf life of tea is influenced by its type, processing method, and storage conditions. While tea leaves do not spoil if kept away from heat, water, light, and air, their flavor and content can degrade over time. Storing tea in airtight containers immediately after purchase can extend its shelf life [17](#page=17) [60](#page=60). #### 5.1.1 Shelf life by tea type Different tea types have varying durations for optimal consumption: * **Green tea:** Approximately 18 months. Due to being unfermented, its flavor and taste are retained for a shorter period, and the concentration of catechins decreases over time. It is best consumed within a year of production [17](#page=17) [61](#page=61). * **White tea:** Usually 2 years. Beyond this period, the aroma is lost, even with proper storage. Interestingly, white tea is considered a special treasure because its medicinal value increases with longer storage [61](#page=61). * **Black tea:** In bulk, it is about 18 months, while bagged tea lasts 24 months. Stored in tins or aluminum foil bags, it can last about 3 years, and in paper bags, for 2 years [61](#page=61). * **Oolong tea:** About 2 years. For loose leaf in bulk, the shelf life is shorter, and it also depends on the degree of fermentation and storage method [61](#page=61). #### 5.1.2 General shelf life guidelines * Sealed packaged tea can typically last from 12 months to 36 months [60](#page=60). * Tea can last 18 months or more if storage conditions and transportation are maintained properly [17](#page=17). * The flavor and content of teas can be maintained for up to 2 years under optimal conditions [17](#page=17). * Tea is often shipped 3-4 weeks after harvest, as prices are highest at the beginning of the season [17](#page=17). #### 5.1.3 Shelf life of prepared and unprepared tea The document outlines different shelf lives for tea based on its preparation state and storage location: | State | Storage Location | Past Date | | :---------- | :--------------- | :------------ | | Unprepared | Pantry | 6-12 months | | Unprepared | Freezer | 1-2 years | | Prepared | Refrigerator | 3-5 days | | Prepared | Freezer | 6-8 months | Packaged tea, loose tea, and powder iced tea mix all last 6-12 months in the pantry and 1-2 years in the freezer. Prepared tea lasts 3-5 days in the refrigerator and 6-8 months in the freezer [62](#page=62). ### 5.2 Cost estimation for tea production Estimating the cost of tea production involves several key components, as illustrated by a pie chart and detailed explanations. The primary categories contributing to the overall cost are raw ingredients, employee expenses, premise costs, equipment, advertising and promotion, and technology expenses [63](#page=63) [64](#page=64). #### 5.2.1 Breakdown of cost components * **Raw ingredients:** This forms a significant portion of the cost, approximately 40% [63](#page=63). * **Employee expenses:** These account for about 30% of the total cost. This includes salaries, employee provident fund contributions, medical funds, uniforms, and safety clothing [63](#page=63) [64](#page=64). * **Premise:** Costs related to the physical location contribute around 20%. This includes architectural plans and modifications such as electrical work, lighting, painting, security systems, ventilation, and plumbing [63](#page=63) [64](#page=64). * **Equipment:** This category represents roughly 10% of the expenses. It includes machinery like tea machines and essential furniture, as well as safety and health items like smoke alarms and first aid kits [63](#page=63) [64](#page=64). * **Advertising and Promotion:** These efforts account for 10% of the cost. This covers branding elements like logos, websites, business cards, brochures, and signage [63](#page=63) [64](#page=64). * **Technology expenses:** These represent 10% of the costs. This includes hardware such as computers, printers, and scanners, as well as software for Wi-Fi, inventory, and billing [63](#page=63) [64](#page=64). * **Insurance:** This is a component of the overall cost, covering repairs and replacement of any damages [64](#page=64). > **Tip:** Understanding the percentage allocation of each cost component is crucial for effective financial planning and identifying areas for potential cost optimization in tea production. > **Example:** If the total estimated cost for a tea production operation is 10,000 dollars, then raw ingredients would cost approximately 4,000 dollars (40% of 10,000 dollars), and employee expenses would be around 3,000 dollars (30% of 10,000 dollars). --- ## Common mistakes to avoid - Review all topics thoroughly before exams - Pay attention to formulas and key definitions - Practice with examples provided in each section - Don't memorize without understanding the underlying concepts

| Term | Definition | |------|------------| | Green tea | A type of tea processed from the leaves of the Camellia sinensis plant that undergoes minimal oxidation, retaining its green color and many of its natural compounds. | | Camellia sinensis | The plant species from which all true teas, including green, black, oolong, and white teas, are derived. | | Catechins | A group of antioxidants found abundantly in green tea, known for their potential health benefits, including anti-oxidative and anti-microbial properties. | | Fermentation (in tea processing) | Refers to the enzymatic oxidation of tea leaves, which develops characteristic flavors and colors. Green tea processing aims to stop this process early to retain its fresh characteristics. | | Withering | The initial stage in tea processing where harvested leaves are spread out to reduce their moisture content and become pliable for further manipulation. | | Plucking | The process of harvesting young tea leaves and buds from the tea plant, typically using hands or specialized machines, with careful selection for quality. | | Fluidized Bed Dryer | A drying technology where air is passed through a bed of granular particles (tea leaves) causing them to float, leading to efficient and uniform drying. | | Microwave Dryer | A drying technology that uses microwave energy for rapid internal heating of tea leaves, based on the oscillation of polar molecules. | | Infrared Dryer | A drying technology that utilizes infrared radiation to heat tea leaves, offering faster drying times and potential for selective heating. | | Packaging | The materials and methods used to contain and protect tea, influencing its preservation, shelf life, and market appeal. | | Labelling Claims | Statements made on product labels intended to inform consumers about product quality, sensory attributes, content, or intended functions. | | Shelf Life | The period during which a tea product is expected to remain in an acceptable condition for consumption, maintaining its quality and characteristics. | | Food Law | Regulations and standards governing the production, processing, labeling, and sale of food products, including tea, to ensure safety and consumer protection. | | Total Ash | The inorganic residue remaining after a sample of tea has been ashed, used as a parameter in food analysis and regulation. | | Water Soluble Extract | The portion of tea that dissolves in boiling water, indicating the concentration of soluble solids, a parameter relevant to tea quality and regulation. | | Oxidation | A chemical process in tea manufacturing where enzymes in the tea leaves react with air, altering the leaf's color, flavor, and chemical composition. | | Fixing (tea processing) | The step in tea processing, often involving heat, used to halt enzymatic activity and prevent further oxidation, thus preserving the tea's color and flavor profile. |