A kind of processing method of instant extra-strong tea powder
Technical field
The present invention relates to a kind of processing method of instant tea powder, more specifically related to a kind of processing method of instant extra-strong tea powder.
Background technology
Instant tea is a kind of solid beverage tea that can be dissolved in water rapidly.Instant tea has pure tea and adds two types of material allotment tea, and pure tea is common has instant black tea, instant oolong tea, instant jasmine tea etc.Add material allotment tea black tea, green tea, oolong tea and lemon black tea, milk tea, the various fruity instant tea that contains sugar arranged.The principal item of China's instant tea has instant black tea, instant green tea, health-care instant tea, also has the concentrated tea juice of undried, like the oolong tea inspissated juice etc.
Instant tea manufacturing process comprises: extract, filter, purify, concentrate, drying etc.Instant tea processing is not simply with the millet paste concentrate drying just, and it must overcome the disadvantage of indissoluble, easy deliquescence, no tea perfume.Extraction is that to adopt water be the soluble substance in the solvent extraction tealeaves, and its method has boiling water to brew extractions, diacolation to extract, extract continuously etc., and the concentration that preceding two kinds of methods are extracted has only 1-5%, and a kind of 15-20% that reaches in back is improved the efficient that concentrates with drying like this.
Common filtering technique is all adopted in the production of traditional tea juice concentrating, like plate compression, smart filter etc.Adopt the advantage that common filtering technique has simply, cost is low, but the muddy degree of product is high, viscosity is big, and after the dilution, millet paste is owed clear, and the pectin in the tea, albumen, starch are prone to form muddy and deposition.Japan Patent JP92 1 discloses and in tea extract, has added caseinate in the prior art, correspondingly network with removed active ingredient in a large amount of tea juice, but can cause tea juice flavour to reduce.JP93-51260 discloses a kind of tea juice concentrating that adopts tannase to separate with film to combine or the manufacturing process of instant tea powder; This technology is because the employing molecular cut off is 5000 milipore filter; Thereby can hold back the active ingredient in a large amount of tea juice, cause tea juice flavour light.
The filter liquor that contains large quantity of moisture, technological requirement that also must be when concentration process just can reach drying.Kinds such as at present method for concentration has that vacuum concentrates, freeze concentration and film concentrate, the extensive use in food industry of these methods.Cardinal principle is some difference of utilizing liquid, solid two to mix at branch, and the separation method of acquisition solute and solvent can be obtained the concentrate of variable concentrations.Owing to when certain material in the tealeaves at high temperature is heated for a long time, account temperature and time, see from the security of tealeaves, require " low temperature is in short-term ", examine filter from processing technology and also must cause low pressure.In the production of instant tea, using at present maximum is that vacuum concentrates, the film method for concentration, is characterized in not heating, and there is not phase transition process in transpiring moisture, is a kind of method for concentration favourable to tea leaf quality.So-called film concentrates, and selects half a saturating permeable membrane of porosity in fact exactly, only permit hydrone and see through, and tealeaves dry composition can not see through, and like this moisture is reduced to a certain degree, reaches concentrated purpose.
Tea beverage market was fiery unusually in nearly 2 years, even under the background of global economic crisis, tea beverage market also with double-digit speed increment in every year, wherein largely comes from the approval of consumer to the tealeaves healthy functions.On the basis of conventional black, green tea, three to get profit, enterprise such as Chef Kang releases oolong tea, extra-strong tea beverage successively, receives the consumer's of large quantities of hobby semi-fermented teas fan, market development is swift and violent.But some enterprises adopt tealeaves directly to extract with the concentrate proportioning is mixed to get, and produce comparatively complicated.
Summary of the invention
The invention provides a kind of processing method of instant extra-strong tea powder, is raw material with the extra-strong tea, and the method for employing adverse current lixiviate in conjunction with technology such as smart filter, film concentrate, has kept the characteristics of the fragrant height of extra-strong tea, the dense alcohol of flavor effectively.
The present invention adopts following technical scheme:
The processing method of a kind of instant extra-strong tea powder of the present invention is a raw material with the dried tea of Iron Guanyin, and processing method comprises that adverse current lixiviate, separation, smart filter, ceramic membrane filter, film concentrate and be dry; The temperature of said adverse current lixiviate is 70-80 ℃, extraction time 25-30min.Said drying is vacuum freeze drying or spray-drying.
Tea, water weight ratio 1:13 in the said adverse current lixiviate.
Adopt the water after handling in the said adverse current lixiviate; The German degree in water after the said processing≤1, colorless and odorless do not have the visible impurity of naked eyes, and the pH value is controlled at 6.5-7.5.
After the extract of counter-flow extraction is crossed 160 mesh filter screens, carry out heat exchange cooling, make temperature≤45 ℃; The filtrating that obtains is separated with disk centrifuge, and alkali cleaning in per 8 hours once; The clarified solution that utilizes micro-filtration membrane that separation is obtained then carries out the essence filter, and filtering accuracy is 5 μ m; Fluid is carried out ceramic membrane filter.
The alkali that adopts in the said alkali cleaning is food grade NaOH.
The frequency of butterfly seperator is 6000 rev/mins, and the frequency of separation is 1 time/3 minutes.
It is 0.2 μ that said ceramic membrane filter adopts the film precision; Cleaned once feed temperature in the ceramic membrane≤45 ℃ in the every 5-6 of ceramic membrane hour.
Said film concentrates and adopts reverse osmosis membrane to concentrate fluid concentration>=15%; Reverse osmosis membrane concentrate feed liquid temp≤45 ℃; Reverse osmosis membrane concentrates fluid and filters with 300 mesh filter screens, and filtrating is carried out drying.
Remarkable advantage of the present invention:
The instant extra-strong tea powder that adopts processing method of the present invention to make, water brew the back color and are yellow green, near delicate fragrance type Iron Guanyin color, and are different from traditional dark oolong tea, and the soup color stability is better.The present invention adopts low-temperature extraction, and normal temperature concentrates and vacuum freeze drying combines, and has reduced process loss, has kept the characteristics of the high aromatic alcohol of Iron Guanyin, and mouthfeel is near former tea.
The specific embodiment
Embodiment 1
1, water treatment: adopt the German degree in water≤1 after ion-exchange obtains handling, colorless and odorless does not have the visible impurity of naked eyes, and the pH value is controlled at 6.5-7.5;
2, counter-flow extraction: with the dried tea of Iron Guanyin is raw material, and the water after the processing of 13 times of weight of adding adopts counterflow extraction apparatus to carry out the tealeaves lixiviate, and extraction temperature is 80 ℃, extraction time 25min;
3, conveyer belt filters: leaching liquor is crossed 160 mesh filter screens.
4, plate-type heat-exchange: adopt the plate type heat exchanger heat exchange, chilling temperature is below 45 ℃;
5, the dish formula is separated: leaching liquor adopts disk centrifuge to separate per 8 hours alkali primaries;
6, smart filter: the use filtering accuracy is that the clarified solution that the doughnut of 5 μ m obtains separation carries out the essence filter;
7, counter-infiltration: adopt reverse osmosis membrane concentration step 6 fluid concentration>=15%; Reverse osmosis concentration feed temperature≤45 ℃;
8, filter: concentrate fluid and filter with 300 mesh filter screens;
9, vacuum freeze drying: filtrating is carried out freeze drying, obtains yellow crystalline particles, is instant extra-strong tea powder.Get in 60 ℃ of water that 0.4g tea powder is dissolved in 200ml, the soup look yellowish green is bright, and giving off a strong fragrance has a little flowers and fruits perfume (or spice), and taste is clearly pure and strong, has light fermentation oolong tea local flavor.
10, packing, preserve: pack environment temperature≤25 ℃, humidity≤45%; In environment temperature≤30 ℃, humidity≤65%, the shady and cool ventilation place stores, and the shelf-life is 24 months.
Embodiment 2
Adopt same steps as to carry out embodiment 1, obtain instant extra-strong tea powder, carry out moisture, Tea Polyphenols, caffeine content detection.
Moisture detecting method: (GB/T18798.3-2008), Tea Polyphenols detection method (GB/T 21733-2008), caffeine detection method (GB/T 8312-2002 UV method)
Microorganism detection method: total plate count (GB/T4789.2-2010), coliform (GB/T4789.3-2010), mould and saccharomycete (GB/T4789.15-2010)
The result is following:
Physics and chemistry: moisture≤5%, Tea Polyphenols>=35%, caffeine>=5%.
Microorganism: total number of bacteria≤10000cfu/g, mould and yeast≤100cfu/g, coliform≤30MPN/100g, pathogenic bacteria must not detect.