Tom qab cov khoom raw yog pretreated, nws ncaj qha nkag mus rau hauv lub freezing system. Nyob ntawm kev siv cov khoom lag luam thiab cov khoom siv khov, ua ntej - ntim lossis xa tawm - ntim khov tuaj yeem siv tau. Lub tshuab khov khov yog tsis tu ncua (batch), ib nrab- cov kav dej tsis tu ncua thiab tsis tu ncua. Cov khoom siv khov nab kuab ua lag luam muaj xws li:
①Blowing lub freezer, feem ntau yog siv lub freezer fluidized (disk hom lossis siv hom) thiab tsau tshuab lub freezer;
② Cov hlau nto tiv thaiv lub freezer feem ntau yog siv cov kab rov tav phaj lub freezer thiab particle freezer;
③ Cov kua evaporative freezer feem ntau yog siv cov kab rov tav kua nitrogen lub freezer. Qhov kev xaiv ntawm qhov txias txias yuav tsum tau txiav txim siab los ntawm cov khoom zoo thiab kev lag luam. Cov teebmeem ntawm kev khov kho ntawm cov khoom zoo yog khov ceev thiab qhuav noj.
Siv cov txheej txheem khov ua ntej ntim, feem ntau lawv siv lub txaj fluidized kom ua tiav sai - khov ntawm cov txiv hmab txiv ntoo, thiab cov khoom tau los yog xoob. Nyob rau hauv qhov kub ntawm -26--30 degree, thaum cov khoom muab tso rau ntawm ib tug tuab ntawm 30-40 hli, lub freezing lub sij hawm ntawm blueberries, raspberries, strawberries thiab cherries tsuas yog 4-15 feeb. Lub freezing ceev ntawm cov kua nitrogen freezing txoj kev yog ceev, thiab cov dej khov muaju yog heev me me, uas yog tshwj xeeb tshaj yog haum rau berries nrog mos ntaub so ntswg. Thaum lub sij hawm tsim khoom, cov txiv hmab txiv ntoo yog thauj mus rau hauv qhov ceev-freezing qhov los ntawm txoj siv conveyor, txau nrog kua nitrogen, thiab khov tam sim ntawd. Piv txwv li, lub sijhawm khov ntawm strawberry los ntawm 20℃rau -18℃tsuas yog 2 feeb, thiab cov ntaub so ntswg ntawm strawberry hloov me ntsis. Tom qab 90 feeb ntawm thawing, cov kua txiv poob yog 50% qis dua li ntawm cov khoom lag luam ceev ceev, tab sis tus nqi siab dua. Txoj kev khov tom qab ntim khoom yog tsim rau: ① khov khov ntawm cov txiv hmab txiv ntoo qab zib; ② khov ntawm cov txiv hmab txiv ntoo zoo li raspberries thiab txiv hmab txiv ntoo overripe xws li strawberries; ③ Lub khw muag khoom ntim ntim nrog cov kua qab zib lossis qab zib. Lub freezing system feem ntau siv cov kab rov tav txhuas phaj lub freezer (yog tias yuam kev siv, qhov kub ntawm lub phaj yog -4 degree, thiab lub sij hawm khov yog li 30min thaum lub ntim thickness yog 25 hli) thiab tsau tshuab lub freezer (cua sov yog feem ntau yog -38-- 40 degree, cua ceev 4-7m / s).
Txiv hmab txiv ntoo sai-txheej txheej txheem txheej txheem ntawm ceev-frozen txiv hmab txiv ntoo yog: raw khoom xaiv, tu, grading, shaping kho (xws li tev, pitting, txiav, thiab lwm yam), ntxiv qab zib, ntxiv vitamin C thiab lwm yam tshuaj tiv thaiv, ntim (los yog tej), ceev - khov., Frozen.
Cov khoom ntawm cov txiv hmab txiv ntoo raw khoom ua si lub luag haujlwm txiav txim siab hauv qhov zoo ntawm cov khoom tiav. Cov txiv hmab txiv ntoo siv rau khov yuav tsum haum rau khov thiab khaws cia. Tom qab thawing, tus thawj cov ntaub so ntswg lub xeev thiab brittleness yeej tswj, thiab lub ripening yog nruab nrab, cov tsos yog zoo huv si, thiab nws tsis yooj yim rau oxidize thiab hloov xim. Cov txiv hmab txiv ntoo uas nquag siv yog txiv duaj, apricot, pear, kua, plum, strawberry, raspberry, melon, cherry, mango, pineapple, kiwi thiab lwm yam. Lub hom phiaj ntawm kev ntxiv qab zib yog txhawm rau tiv thaiv kom tsis txhob muaj dej ntau los ntawm kev khov thiab rhuav tshem cov ntaub so ntswg ntawm cov txiv hmab txiv ntoo, thiab tiv thaiv oxidation ntawm huab cua, ua kom tsis muaj zog ntawm oxidase, thiab zam kom tsis txhob muaj xim ntawm cov tawv nqaij, uas yog ib qho tseem ceeb hauv kev tswj cov txiv hmab txiv ntoo. Soak cov txiv hmab txiv ntoo nrog 2-4% vitamin C tov rau kaum ob feeb thiab tom qab ntawd khov nws, uas tuaj yeem ua rau cov xim sai sai -cov txiv hmab txiv ntoo khov zoo ib yam li cov txiv hmab txiv ntoo tshiab. Ua ntej ntim los yog ib tug neeg ceev ceev khov, nws yuav tsum tau drip-dried nrog ib tug co dewatering ntaus ntawv. Tus nqi pH ntawm cov txiv hmab txiv ntoo yog 2.5 txog 5.0, yog li cov khoom siv pretreatment yuav tsum tau ua los ntawm stainless hlau.
