Trong quá trình nấu bia vấn đề độ đục trong bia là vấn đề rất quan trong đặc tại công đoạn lọc bia với nồi lọc lauter Tun, thông thường các nhà máy bia lớn có thiết bị kiểm soát và điều khiển bơm bằng đầu do độ đục online kiểm soát giá trị EBC. Trong bài giảng này nói chi tiết các vấn đề phát sinh và control độ đục trong quá trình nấu bia. Giáo trình song ngữ (Anh - Việt) giúp người đọc dễ dàng hiểu rõ. Tài Liệu này biên soạn gốc của chuyên gia Đức.
ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITES rd ASIA PACIFIC CONVENTION 2014 33 HO CHI MINH CITY, VIETNAM ROLAND FOLZ DIRECTOR TECHNOLOGIES & INNOVATION PENTAIR FOOD & BEVERAGE FOOD & BEVERAGE TURBIDITY • Turbidity is a visual percepIon and depending of the intensity not visible for the human eye • Risk: the client gets probably a negaIve impression FORMS OF TURBIDITY, EXAMPLES: • Colloidal: „classical“ protein-‐polyphenol-‐complexes o Chill haze (reversible) o Permanent haze (irreversible) • Carbohydrate-‐related: α-‐Glucan o Wort ProducIon Process (mash-‐ and lauter technology) Raw materials → gelaInizaIon temperature o Yeast Management ExcreIon of glycogen Autolysis PENTAIR ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES TURBIDITY IN BEER CAUSE/ EFFECT DIAGRAM Turbidity in Beer PENTAIR ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES FACTORS THAT INFLUENCE TURBIDITY FACTORS INFLUENCE ConcentraIon of the reacIon partners proteins and polyphenols Temperature and movement speed-‐ up of chemical reacIons Metal ions Fenton-‐Haber-‐Weiss reacIon -‐ catalyIc Impact; leads to complexes Oxygen Adhering to easily oxidised compounds Light formaIon of reacIve oxygen species pH PENTAIR influence of the solubility of proteins by protonaIon ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES STANDARD PROCEDURE FOR TURBIDITY IDENTIFICATION I. PRELIMINARY APPROACH: a) Visual Check – naked eye observaIon and descripIon b) Turbidity measurement (forward and lateral movement) c) pH-‐ measurement SeparaIon of turbidity compounds by: min centrifugaIon (2700rpm) + 3 washing steps Membrane filtraIon PENTAIR ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES BASIC PHYSICS OF TURBIDITY MEASUREMENT • In Terms of light-‐transit in beer the light is reflected/scadered by parIcles, and Quality control equipment captured by detectors ! posiIoned in different angle between the incident angle SIDEWARD-‐SCATTERING (90°) → mainly parIcles < 1 µm o High-‐molecular complexes of proteins, polyphenols and carbohydrates o … FORWARD SCATTERING 11°/13°/25° → mainly parIcles > 1 µm o Yeast cells o Kieselgur, PVPP o Inorganic material (e.g CaOx-‐cristals) o … PENTAIR ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES Light-‐scadering 25º APPLICATION, IN BREWING INDUSTRY BREWING PROCESS Lautertube Turbidity Brewing Kedle CO2 Keg Filling Bodle/Can Filling Possible recirculaIon in case of natural cloudy beer CO2 CO2 Wort Cooler Blending CO2 Beer filter Bright Beer Tank PENTAIR Whirlpool ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES Storage/FermentaIon tank MEASURING DEVICES Laboratory In-‐line Laboratory 90 & 90/25 In-‐line 90 & 25 BENEFITS • Most convenIonal turbidity meters that incorporate the MEBAK standards • Excellent correlaIon between lab and process • Modular & flexible in-‐line turbidity measuring system – Dynamic switching of different measuring ranges for maximum accuracy – Extendable with 2nd turbidity sensor – separate control unit for ergonomic posiIoning – large and clear color display – calibraIon with PC somware while control unit stays in the process PENTAIR ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES BASIC BEER MEMBRANE FILTER LINE CONCEPT TURBIDITY MEASUREMENT – MEMBRANE FAILURE CONTROL BBT SV UBT MEMBRANE FILTER FBT CARBO-‐ BLENDER SF TURBIDITY MEASUREMENT – YEAST LOAD CONTROL PENTAIR TURBIDITY MEASUREMENT – STANDARD EBC 90° ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES SV: UBT: FBT: SF: BBT: Storage Vessel Unfiltered Beer Tank Filtered Beer Tank Security Filter Bright Beer Tank ADDED VALUE TURBIDITY MEASUREMENT BMF YEAST LOAD CONTROL • Incoming yeast for the BMF is maximized on average 5 million and peaks of 15 million for 5 minutes – Normal brewing processes can easily reach these values, but failures in tank bodom removal can cause higher values • Too high yeast load can lead to break-‐down of the BMF for hours – Losing valuable producIon Ime MEMBRANE FAILURE CONTROL • Signal send to SCADA/Operator that one of the membrane fibers has a leak -‐ The membrane module must be replaced • • Process conInues because security filter (cartridges) retains the yeast cells On Ime membrane module replacement enhances life Ime of the cartridge – Lowering operaIonal costs EBC 90°MEASUREMENT • Usually programmed as info only – Operator can start workflow to determine cause and find soluIon PENTAIR Beverage Systems ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES 10 ESTABLISHING NEW APPROACHES MODIFIED PHOTOMETRIC IODINE TEST: • DisIncIon of a-‐glucan turbidity based on the origin • • • • o glycogen: process related turbidity o amylopecIn: raw material related turbidity SeparaIon of macromolecular turbidity units of beer Staining with iodine test: blue coloring agent -‐ „iodine-‐ starch“ DifferenIaIon with spectroscopic methods possible Improvement approach: complete separaIon of amylopecIn and glycogen should be achieved by GPC Spektrenvergleich 2,5 Extinktion Extinktion 1,5 Amylopektin λmax:545 nm Glykogen λmax:465 nm 0,5 400 450 500 550 Wellenlänge in 600 nm 650 700 Wellenlänge in nm 1mg/mL Amylopektin PENTAIR ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES 1mg/mL Glykogen 13 ESTABLISHING NEW APPROACHES 0,16 • SeparaIon and fracIonaIon of samples 0,14 0,12 • No complete separaIon of glycogen and Glykogen/Amylopektin Mix 0,1 Amylopektin n io tk 0,08 in tx E 0,06 amylopecIn Glykogen • Mixing of fracIon 7-‐10 0,04 0,02 0 10 15 20 Fraktion 25 30 35 Spectroscopic analysis of fracIon 7-‐10 • IdenIficaIon of 2 different maxima • ClassificaIon based on wavelength • SeparaIon of low-‐molecular residual substances DIFFICULTIES: • RelaIvely low adsorpIon strength • SIll clearly peak-‐overlaps • Work is being conducted with spiked beer => different behavior of natural turbidiIes 0,25 0,2 n0,15 io tk in tx E 0,1 0,05 400 450 500 550 600 650 700 Wellenlänge nm • Problems with quanIficaIon PENTAIR ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES 14 SCANNING ELECTRON MICROSCOPY SCANNING ELECTRON MICROSCOPY (REM) • ResoluIon [...]... picture – Eosin Yellow Table 2 – Results of microscopy and staining Color reagent Observa`on Eosin yellow • clearly rosy coloring– proteins • the finer the material, the darker the staining CONCLUSION: • In this case main reason for turbidity consists of proteins, which is one of the most turbidity caused materials in beer PENTAIR ROOTS... Alpha-Amylase 12 ESTABLISHING NEW APPROACHES MODIFIED PHOTOMETRIC IODINE TEST: • DisIncIon of a-‐glucan turbidity based on the origin • • • • o glycogen: process related turbidity o amylopecIn: raw material related turbidity SeparaIon of macromolecular turbidity units of beer Staining with iodine test: blue coloring agent -‐ „iodine-‐ starch“ DifferenIaIon... -‐ Results of microscopy and staining Color reagent Methylene blue Thionine PENTAIR Observa`on • clearly blue coloring – polyphenols Microscopic picture– Thionine • Rosy, purple coloring shows presence of sour polysaccharides • Staining pecIn with thionine leads to same coloring like sour polysaccharide • Because... examined in REM orange: sedimentaIon blue line: object slide thin film organic material PENTAIR ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES 23 CASE UNDER EXAMINATION NO IV FOREIGN PARTICLES INTERPRETATION OF RESULTS: • Material consists of thin, rolled-‐up layer („thin film“) • Layer spectrum is presented in comparison... possible use of fluorescent staining agents • The installaIon of a Scanning Electron Microscope in the VLB, will lead to: o IdenIficaIon of elemental composiIon of inorganic parIcles in house o faster handling of samples and delivery of results • Full implementaIon of the Modified Photometric Iodine Test (including separaIon of the compounds... separaIon of amylopecIn and glycogen should be achieved by GPC Spektrenvergleich 2,5 Extinktion Extinktion 2 1,5 Amylopektin λmax:545 nm Glykogen λmax:465 nm 1 0,5 0 400 450 500 550 Wellenlänge in 600 nm 650 700 Wellenlänge in nm 1mg/mL Amylopektin PENTAIR ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES 1mg/mL Glykogen 13 ESTABLISHING NEW APPROACHES... deeper invesIgaIon, special analyses such as PCR, HPLC, LCV, Electrophorese, Ion chromatography, Enzyme tests, Iodine tests or EDX-‐analysis are conducted to the samples, in order to gain more detailed informaIon on the composiIon and possible origin of the turbidity causing parIcles • Finally, an open discussion with the breweries is seeked in. .. apple pecIn could be involved in the parIcle‘s composiIon ROOTS OF TURBIDITY IDENTIFICATION: CURRENT STATE AND NEW POSSIBILITIES 20 CASE UNDER EXAMINATION NO III CARBONIZED ALCOHOLIC BEVERAGE • ConfirmaIon of presence for fruit pecIn by: STAINING WITH RUTHENIUM RED AND MICROSCOPY Table 9 -‐ Results of microscopy and staining with... differenIaIon of amylopecIn and glycogen important factor of turbidity ID; (mod iodine sample) • „posiIve“ enzyme test; • Slightly increased iodine value " incompletely ! determinaIon provides clearly informaIon about a-‐glucane turbidity decomposiIon of starch PENTAIR ROOTS OF TURBIDITY... microorganisms or foreign par`cles that come into contact with the beer • The VLB approach on turbidity idenIficaIon is based on an ini`al standard visual-‐check, turbidity and pH-‐measurement, followed by a meIculous observa`on of the sample under a light microscope and a staining procedure, using staining agents specific for idenIficaIon of different