Through professional instrumental analysis, it was found that there are more than 500 chemical components of tea, in addition to sugars, proteins, fats, and lipids...three natural substances and other compounds.
Cov tshuaj yej txawv xim, aromas, thiab flavors yog tsim los ntawm lub cev thiab tshuaj hloov thaum lub sij hawm tsim cov tshuaj yej.
Cov tshuaj tshuaj hauv tshuaj yej tuaj yeem muab faib ua peb hom:" tshuaj yej cyanine"," qhuav tshuaj yej" thiab" tshuaj yej kua zaub"..." Tshuaj yej cyanine" hais txog cov tshuaj yej nplooj tshiab uas nyuam qhuav khaws tseg, vim tias cov tshuaj yej tsob ntoo sib txawv muaj qhov ntev sib txawv, txawv ib puag ncig thiab kev cog qoob loo, thiab cov ntsiab lus ntawm lawv yuav txawv."Dried tshuaj yej" yog cov khoom tiav tom qab tsim cov tshuaj yej nplooj. Vim tias qib fermentation ntawm cov txheej txheem ntau lawm txawv, cov khoom xyaw ua ke kuj sib txawv."Tea soup" yog cov kua txiv hmab txiv ntoo uas yaj tom qab cov tshuaj yej qhuav yog brewed rau hauv dej, thiab qhov no yog cov khoom ncaj qha cuam tshuam rau lub cev thaum haus nws.
Qhov feem pua ntawm cov tshuaj yej infusion:
1. Water content:
Cov dej ntsiab lus ntawm cov tshuaj yej tshiab nplooj suav txog li 75 mus rau 80%, thiab cov ntsiab lus dej ntawm cov tshuaj yej qhuav ntawm cov khoom tiav yog tsawg dua 5%.
Thaum cov dej cov ntsiab lus hauv cov tshuaj yej qhuav tshaj 12%, cov tshuaj tiv thaiv ntawm cov tshuaj yej yuav tsis tsuas yog nce mus ntxiv, tab sis kuj nqus cov pa oxygen hauv huab cua, kom cov kab mob yuav ua rau khaus, thiab tom qab ntawd cov tshuaj yej yuav deteriorate los yog ua qaub.
2. Polyphenols:
Qhov no yog hais txog" tshuaj yej polyphenols" peb feem ntau hnov, uas yog lub ntsiab lus rau ntau tshaj 30 hom polyphenols hauv tshuaj yej. Tshuaj yej polyphenols kuj hu ua" tshuaj yej tanning" vim tias feem ntau ntawm lawv tuaj yeem yaj hauv dej. Hu ua" dej-soluble tannins." Xws li: catechins, anthocyanins (flavanols), flavonoids (flavonoids) thiab phenolic acids. Tshuaj yej polyphenols yog nquag auto-oxidation. Tom qab oxidation thiab polymerization, lawv yuav tsim"theaflavins" thiab" thearubigen", uas yuav cuam tshuam rau xim thiab saj ntawm tshuaj yej." Catechin", cov khoom noj muaj txiaj ntsig zoo tshaj plaws hauv tshuaj yej polyphenols, yog cov khoom tseem ceeb uas txiav txim siab xim, aroma thiab saj ntawm tshuaj yej. Nws tseem yog cov khoom tseem ceeb tsim cov tshuaj yej sib txawv. Nws muaj zog astringency thiab iab.
Catechin, tseem hu ua" tannin", suav rau ntau dua 50% ntawm cov khoom hauv tshuaj yej kua zaub. Ntau yam sib txawv, txawv sijhawm xaiv, qhov loj hlob, kev tswj kev cog qoob loo thiab kev hloov pauv huab cua yuav ua rau cov ntsiab lus sib txawv ntawm catechins.
Hauv kev tshawb fawb cov ntaub ntawv luam tawm txawv teb chaws, catechins muaj cov txiaj ntsig zoo ntawm lub cev. Cov khoom xyaw tseem ceeb muaj xws li:
Epicatechin (EC), gallocatechin (GC), epigallocatechin (EGC), epigallocatechin (EGCG), epicatechin gallate (ECG) nyob rau hauv lub caij sib txawv Cov ntsiab lus catechin nyob rau hauv cov qoob loo tshuaj yej nplooj yog raws li nram no: lub caij ntuj sov> caij nplooj ntoos hlav> caij nplooj zeeg> lub caij ntuj no tshuaj yej polyphenols thiab catechins kuj yuav txo nrog qhov nce hauv qhov siab. Npog lub vas dub ua ntej sau cov tshuaj yej ntsuab thaum lub caij ntuj sov. Nws kuj txo cov ntsiab lus ntawm catechins, uas yog npaj los txo cov iab ntawm cov tshuaj yej ntsuab.
Catechin yuav yaj hauv dej kub tab sis tsis yog dej txias, yog li cov tshuaj yej txias brewing yuav muaj tsawg iab. Yog tias koj xav haus catechins noj qab nyob zoo rau hauv koj lub cev, koj tuaj yeem xaiv haus dej tshuaj yej kub.
Feem ntau, catechins hauv tshuaj yej nplooj muaj 10% mus rau 30% ntawm cov tshuaj yej qhuav thiab 40% mus rau 50% ntawm cov khoom xyaw soluble hauv tshuaj yej kua zaub. Lawv tuaj yeem ua ke nrog caffeine hauv tshuaj yej kua zaub kom qeeb qhov cuam tshuam ntawm caffeine rau tib neeg lub cev.
At present, domestic and foreign studies have confirmed that catechins and their oxidized polymers have anti-oxidation, anti-inflammatory, anti-bacterial, anti-cell mutation, anti-tumor and anti-allergic effects on the human body. In addition, they can also strengthen microvascular activity, increase vitamin C intake, Reduce blood cholesterol and low-density lipoprotein content, protect against radiation damage, inhibit blood pressure rise and inhibit platelet aggregation and other physiological effects.
3. Biomass:
The bioalkali in tea includes caffeine, cacao and tea stems, of which caffeine has the most content, accounting for about 2% to 5% of the total amount of dry tea. It is a product of nitrogen metabolism and is found in the tender shoots of tea with strong metabolism. (Tender buds) and spring tea have a high content... When the temperature of the tea soup is lower than 38°C, caffeine will combine with the polyphenols, proteins... and other macromolecular substances in the tea to produce precipitation. Combination and separation at high temperature is an insoluble colloidal precipitation, called emulsification (curd) or "cold muddy"... This emulsification is directly related to the activity of tea soup, and it is also considered in the review of black tea It is one of the indicators to measure the quality of black tea. The greater the activity of the black tea soup, the greater the emulsification effect, which will also increase the freshness of the tea soup. Caffeine accounts for 8-10% of the soluble components of tea soup. Usually 300 mg of caffeine a day is harmless to most adults. Caffeine will be metabolized within a few hours after ingestion and will not accumulate. In the human body. Caffeine and theophylline are macromolecular substances and have a low release rate in cold water. Therefore, drinking cold brewed tea will not take too much caffeine and tea juice, and will not affect the stomach and sleep.
Caffeine muaj physiological cuam tshuam rau tib neeg lub cev xws li stimulating lub hauv paus paj hlwb, refreshing, ntxiv dag zog rau lub plawv, thiab diuresis. Nws kuj yog ib tug bronchial relaxing tus neeg saib xyuas thiab tuaj yeem ceev cov metabolism ntawm cov rog tawg. Txawm li cas los xij, txawm hais tias caffeine muaj nyob hauv tshuaj yej thiab caffeine hauv kas fes yog tib yam khoom, lawv cov tshuaj muaj pes tsawg leeg thiab cov qauv sib txawv. Cov catechins thiab oxidized polymers hauv tshuaj yej tuaj yeem txo cov teebmeem physiological ntawm caffeine ntawm tib neeg lub cev.
4. Amino acids: Cov amino acids nyob rau hauv tshuaj yej muaj qab zib saj thiab yooj yim yaj nyob rau hauv dej, uas txiav txim lub freshness ntawm cov tshuaj yej kua zaub. Kev sib cuam tshuam ntawm cov amino acids thiab catechins yuav hloov lub aroma ntawm tshuaj yej nplooj. Amino acids muaj ntau tshaj nyob rau hauv tshuaj yej buds, high altitude, caij nplooj ntoos hlav thiab lub caij ntuj no tshuaj yej. Lub aroma tsim nyob rau hauv tus txheej txheem ntawm kev ua tshuaj yej, lub" Menner cov tshuaj tiv thaiv" tshwm sim ntawm cov amino acids thiab txo cov suab thaj thaum lub sij hawm roasting, uas muab cov tshuaj yej ib tug roasted aroma. Cov amino acid ntawm cov tshuaj yej roob siab yog 26% siab dua li ntawm Pingdi tshuaj yej, thiab tag nrho cov roj tseem ceeb yog 41% siab dua. Cov ntsiab lus ntawm aldehydes nyob rau hauv roob siab tshuaj yej kuj siab dua, uas yog vim li cas vim li cas roob siab tshuaj yej yog ntau qab thiab refreshing.
5. Tshuaj yej pigment:
Cov pigments nyob rau hauv tshuaj yej muaj xws li fat-soluble pigments thiab dej-soluble pigments. Chlorophyll yog insoluble hauv dej.
Carotenoids (daj pigments) yuav hloov mus rau hauv lub aroma ntawm tshuaj yej thaum lub sij hawm tsim tshuaj yej txheej txheem, thiab muaj cov cuab yeej ntawm absorbing lub teeb, uas yog yooj yim rau oxidized thiab yuav hloov lub zoo ntawm tshuaj yej kua zaub.
Flavonoids, anthocyanins, theaflavins, thearubicins, thearfuscins ... yog dej-soluble pigments thiab txiav txim siab xim ntawm cov tshuaj yej kua zaub.
Flavonols: kwv yees li 0.6% ~ 0.7% ntawm cov tshuaj yej qhuav, uas muaj cov nyhuv ntxiv dag zog rau cov phab ntsa ntawm cov hlab ntsha thiab tshem tawm cov pa phem ntawm tib neeg lub cev.
6. Cov tshuaj tsw qab:
The aroma of tea is determined by the quality of the tea and the manufacturing process. Tea contains more than 300 kinds of aroma compounds.
Cov tshuaj tsw qab hauv tshuaj yej xa mus rau" cov ntsiab lus dav dav rau cov tshuaj tsis haum hauv tshuaj yej". Nyob rau hauv tag nrho cov ntsiab lus ntawm tshuaj yej tshuaj, cov ntsiab lus ntawm aromatic tshuaj yog tsis ntau, yog li cov aroma yog tiag tiag txiav txim siab los ntawm qhov zoo ntawm cov tshuaj yej cyanine thiab cov kev mob ntawm kev ua thiab manufacturing. Feem ntau, cov nplooj tshiab muaj 0.02%, tshuaj yej ntsuab muaj 0.005 ~ 0.02%, thiab cov tshuaj yej dub muaj 0.01 ~ 0.03%. Txawm hais tias tsis muaj ntau yam tshuaj tsw qab hauv tshuaj yej, cov hom yog qhov nyuaj heev.
Raws li kev txheeb xyuas, cov tshuaj yej nplooj muaj ntau tshaj 300 hom tshuaj tsw qab; nplooj tshiab muaj txog 50 yam; ntsuab tshuaj yej muaj ntau tshaj 100 aroma tebchaw; thiab tshuaj yej dub muaj ntau tshaj 300 yam. Cov khoom tseem ceeb ntawm cov tshuaj tsw qab no hauv tshuaj yej yog cawv, phenols, aldehydes, ketones, esters, lactones, nitrogen-muaj cov tebchaw, sulfur-muaj cov tebchaw, hydrocarbons, thiab oxides.
Hauv cov ntsiab lus, cov ntsiab lus tseem ceeb uas tau hais los saum toj no yog qhov aroma ntawm tshuaj yej yog txiav txim siab los ntawm ob qho tib si tshuaj yej ua tshuab thiab hom ntawm cov tshuaj yej tsob ntoo, thiab tsis muaj qhov tsis ntseeg tias aroma ntawm tshuaj yej yog ib qho tseem ceeb uas txiav txim siab qhov zoo. . Muaj ntau ntau yam tshuaj tsw qab hauv tshuaj yej, tab sis cov ntsiab lus me me heev. Cov ntsiab lus ntawm oolong tshuaj yej thiab tshuaj yej dub yog qhov siab, thaum cov ntsiab lus ntawm cov tshuaj yej ntsuab yog tsawg. Lub ntsiab aroma hom: cawv, aldehydes, vinyl cawv, ketones, carboxylic acids, esters, phenols, nitrogen los yog sulfur compounds. Alcohols: Aliphatic alcohols: n-butanol, isobutanol, isoamyl cawv, cis-3-hexenol... etc. Aromatic alcohols: this methanol (apple fragrance), phenethyl alcohol (rose fragrance), phenylpropanol (xws li daffodil fragrance) Terpene alcohols: Linalool, geraniol, nerolinol Aldehydes: Aliphatic aldehydes: Qingye aldehyde Aromatic aldehydes: phenylacetaldehyde, cinnamaldehyde Phenol: Geraniol
Ketones: Cov ntsiab lus ntawm ketones hauv tshuaj yej yog me me, tab sis lawv pab ntau heev. Piv txwv li, lub aroma ntawm B-ionone thiab tshuaj yej ntsuab. Teaspirenone, jasmon (jasmine paj tshuaj tsw qab, kuj yog cov ntxhiab tsw ntawm cov tshuaj tsw qab thiab tshuaj yej tshiab)
Carboxylic acids: Cov ntsiab lus ntawm cov tshuaj no hauv txiv kab ntxwv tshuaj yej yog siab dua li cov nplooj tshiab, tshwj xeeb tshaj yog cov tshuaj yej dub. Qhov feem pua ntawm cov tshuaj tsw qab hauv cov tshuaj yej dub suav txog li 30%, thaum cov tshuaj yej ntsuab tsuas yog 2-3%. Yog li ntawd, hom tshuaj no yog ib qho ntawm cov laj thawj tseem ceeb rau qhov sib txawv ntawm aroma ntawm liab thiab ntsuab tshuaj yej. (Tsis tas li ntawd, cov ntsiab lus ntawm acetic acid feem ntau yog siv los ua ib qho ntawm cov tshuaj yej mildew)
Esters: Esters yog cov khoom tseem ceeb ntawm cov tshuaj tsw qab. Cov esters tsim los ntawm acetic acid thiab aromatic alcohols feem ntau muaj ib tug muaj zog aroma, feem ntau floral. Piv txwv li, hexenyl hexenoate yog lub ntsiab ester hauv tshuaj yej ntsuab. Nws yog cov yam ntxwv ntawm cov tshuaj yej ntsuab thiab tshuaj yej tshiab fragrance. Nws cov ntsiab lus txo qis thaum lub sijhawm khaws cov tshuaj yej ntev dua, thiab cov ntsiab lus ntawm cov tshuaj yej yuav qis dua thaum nws muaj hnub nyoog.
Phenols: Cov ntsiab lus tsawg dua hauv tshuaj yej tsis cuam tshuam rau aroma ntawm tshuaj yej, tab sis yog tias cov tshuaj no nce ntxiv, nws yuav ua rau cov pa luam yeeb lossis haus luam yeeb. Piv txwv li, cov ntsiab lus phenol feem ntau yog siv los ntsuas qhov degree ntawm" haus luam yeeb". Guaiacol thiab nws cov derivatives, cov khoom ntawm kev ua tsis tiav ntawm lignin thiab polyphenols, feem ntau muaj cov pa luam yeeb. Xws li cov tshuaj thiab cov ntxhiab tsw yuav raug tsim thaum lub sij hawm tua cyanine.
Cov tshuaj uas muaj N lossis S: dimethyl sulfide, ib qho ntawm cov tshuaj tsw qab tshiab ntawm cov tshuaj yej ntsuab; dimethyl arsenic, uas muaj ib qho kev pom roasting aroma thaum cov ntsiab lus tsawg, tab sis nws yuav muaj coke thaum cov ntsiab lus siab.
7. Cov protein:
Cov enzymes hauv cov khoom xyaw protein ntawm cov tshuaj yej yog cov catalysts koom nrog" enzymatic cov tshuaj tiv thaiv" Nws kuj yog ib yam khoom uas ua rau kom cov viscosity ntawm cov tshuaj yej nplooj. Ib yam li cov zaub mov zoo tib yam, cov protein nyob rau hauv cov tshuaj yej kua zaub yuav ua rau cov tshuaj yej kua zaub mus rau lub sijhawm ntev. Qhov no yog vim li cas cov tshuaj yej tau tso tseg ntev heev tom qab kub, thiab cov tshuaj yej uas muab tso rau hmo ntuj tsis haum rau haus. Koj tuaj yeem lim cov kua tshuaj yej brewed kom tau cov tshuaj yej Tom qab lub slag, cia nws txias, ces coj mus rau tub yees.
8. Qab Zib:
Tshuaj yej muaj monosaccharides (glucose, galactose, fructose ...), disaccharides (maltose, sucrose, lactose ...) thiab polysaccharides (cellulose, hemicellulose, pectin, starch, active polysaccharides, lipopolysaccharides). Monosaccharides thiab disaccharides yog soluble nyob rau hauv dej thiab yog ib qho ntawm cov tshuaj uas muab cov tsw ntawm tshuaj yej.
9. Pectin:
Cov ntsiab lus ntawm fructose, carbohydrates thiab amino acids txiav txim siab lub thickness ntawm cov tshuaj yej. Nws tuaj yeem ua rau kom qab zib thiab tuab saj ntawm cov tshuaj yej kua zaub ... Qhov siab siab, siab sprout ntsiab lus.
10. Lipids:
Cov fatty acids uas tsim thaum lub sij hawm hydrolysis yog ib co tsis ruaj tsis khov tshuaj Cheebtsam, uas yuav oxidize nyob rau hauv cov huab cua los ua stale los yog rancid tsw... Khaws cov tshuaj yej qhuav kom deb ntawm kub, lub teeb, thiab oxygen.
PS: fluorine
Feem ntau, cov tshuaj yej tiav lawm muaj txog 150 ~ 350ppm ntawm fluorine. Qhov tseeb, nyob rau hauv tus txheej txheem ntawm brewing tshuaj yej, fluorine tsis tso tawm tag nrho ib zaug, tab sis maj mam tso tawm ntawm ib tug concentration ntawm txog 1ppm, yog li kuv nyiam ua tshuaj yej thiab haus tshuaj yej cov neeg feem ntau tsis yoog rau cov hniav lwj. Cov ntsiab lus dej: Cov dej ntsiab lus ntawm cov tshuaj yej nplooj tshiab nyob ntawm 75-80%, thiab cov ntsiab lus dej ntawm cov tshuaj yej qhuav ntawm cov khoom tiav yog tsawg dua 5%. Thaum cov dej cov ntsiab lus hauv cov tshuaj yej qhuav tshaj 12%, cov tshuaj tiv thaiv ntawm cov tshuaj yej yuav tsis tsuas yog nce mus ntxiv, tab sis kuj nqus cov pa oxygen hauv huab cua, kom cov kab mob yuav ua rau khaus, thiab tom qab ntawd cov tshuaj yej yuav deteriorate los yog ua qaub.