Supplementary Software LZV 570 Brewery Analysis
Contents
1. e Water bath suitable for boiling water e Water bath 20 C e Spectrophotometer 570 nm e 10mm rectangular cuvette OS grade Reagents e Colour reagent Dissolve 10 0 g disodium hydrogen phosphate NasHPO x 12 H20 6 0 g potassium dihydrogen phosphate KH PO 0 5 g ninhydrin and 0 3 g fructose in H O and make up to 100 ml This solution remains stable for 2 weeks in a dark bottle The pH must be 6 6 6 8 e Dilution solution Dissolve 2 g potassium iodate in 600 ml H 0 and add 400 ml 96 ethanol e Stock solution Dissolve 107 2 mg glycine in 100 ml H20 Keep this stock solution at 0 C e Standard solution Make up 1 ml stock solution to 100 ml with H20 This standard solution contains 2 mg l amino nitrogen Sample preparation 1 Dilute wort 100 fold beer 50 fold 1 3 mg l amino nitrogen 2 Analyse sample standard solution and blank value solution three times 3 Pipette 2 ml of the diluted sample or the standard solution or H20 into a test tube 4 Add 1 ml colour reagent and mix 22 Working procedures 5 Loosely close test tube with glass stopper to prevent evaporation losses 6 Heat for exactly 16 min in boiling water in a water bath then cool for 20 min in a water bath at 20 C 7 Add 5 ml dilution solution 8 Measure the absorbance within 30 min in a 10 mm rectangular cuvette at 570 nm against a blank value solution treated in the same way H O colour reagent 9 Correction for dark wo2. 10 ml diluted sample and shake b Place in a 70 C water bath for 70 minutes avoid direct sunlight and ensure that at most the temperature in the bath decreases only briefly by 1 2 C when the test tubes are introduced c When the reaction time has elapsed cool the test tubes quickly to 20 C strongly flowing cold water or cooling bath d Measure the yellow colour immediately in 10 mm rectangular cuvettes at 448 nm against H20 Results Thiobarbituric acid number TBN dimensionless number Standard values Light finished wort lt 45 Light cold wort after wort cooling lt 60 Literature MEBAK Brautechnische Analysenmethoden Ath Edition 2002 Volume Il pp 35ff 2 9 1 Procedure for measuring thiobarbituric acid number in beer and wort Stored Programs 3 2 g 1 Prepare samples and blank value solution as described in the working procedure 2 Select Stored Programs in the Main Menu Select test number 811 3 Insert zero value cuvette containing distilled water into the cell compartment Close the cell compartment Touch Zero phenols 909 Total Kjeldahl N I 4 Insert blank value cuvette see sample preparation into the cell Cancel Select by fhe ee compartment Close the cell compartment Touch Read Display E1 5 Insert the sample cuvette containing the prepared sample into the cell compartment Close the cell compartment Touch Read The result is displayed 36 811 TAN beer wort 8 49
3. antifoam emulsion 3 Regulate the steam supply so that about 25 ml distillate are obtained in 2 min 4 Collect the distillate in 25 ml measuring flasks 42 Working procedures 5 Pipette 10 ml of the mixed distillate into each of two 50 ml Erlenmeyer flasks main value solution blank value solution 6 Blank value solution e Add 2 5 ml 4N hydrochloric acid 7 Main value solution e Add 0 5 ml 1 2 phenylenediamine solution mix and allow to stand in a dark place for 30 min e Then add 2 ml 4N hydrochloric acid 8 Within 20 min measure the absorbance of the main value solution against the blank value solution at 335 nm in 20 mm rectangular cuvettes Results The result is expressed in mg kg to two decimal places Accuracy SD 0 01 Required value For light Vollbier beer with a high original gravity lt 0 15 mg kg Remarks If series of analyses are carried out the apparatus need not be cleaned or rinsed between the individual determinations but can be refilled immediately with beer after it has automatically emptied After a series of distillations the adhering residues should be removed with sodium hydroxide solution or some other suitable cleaning agent Any acetohydroxy acids that are present in beer after the filling stage are oxidised to diketones in the presence of O2 Before the actual analysis the beer sample can be thermostated at 70 C for 1 5 hours for the purpose of analysing the total diketo
4. as the long term constancy of its taste Principle Reductones reduce a certain amount of Tillmann s reagent 2 6 dichlorphenol indophenol sodium DPI within a given period of time The decolouration of the reagent is measured with a spectrophotometer and calculated Measuring range 0 100 Accessories e Spectrophotometer 520 nm e 10mm rectangular cuvette OS grade e Stopwatch e Water jet pump Reagents e 2 6 Dichlorphenol indophenol 0 005M DPI solution molecular weight of the sodium salt 290 08 a Weigh approx 100 mg DPI into a beaker add approx 25 ml H20 and dissolve by heating to about 60 C b Allow to cool then rinse into a 50 ml measuring flask make up to 50 ml and pass through a tinstrip filter c Introduce 10 ml filtrate 1 g Kl and 2 ml H S0O 1 6 into a 150 ml Erlenmeyer flask titrate with 0 01N sodium thiosulphate solution until a colour change occurs against starch paste d Added volume ml x 14 5 mg indicator in 100 ml e Dilute remaining filtrate so that 100 ml contain 145 mg f The solution remains stable for about 1 week if kept at 4 C in brown bottles filled to the brim e Phosphate citrate buffer pH 4 35 e Dissolve 31 60 g disodium hydrogen phosphate NagHPO x 12 H20 and 11 75 g citric acid CgHgO7 x H20 in H20 and dilute to 1 I Sample preparation 1 Heat the beer to 20 C and expel carbon dioxide under a vacuum water jet pump 15 Working procedures
5. for measuring iso a acids and a acids Stored Programs Select by Program Cancel Number Options 813 Iso a and a acids UV VIS 255 nm 23 4 mg l Iso a acids 18 7 mg l a acids 26 SEP 2005 10 45 10 1 Prepare samples and blank value solution as described in the working procedure 2 Select Stored Programs in the Main Menu Select test number 813 3 Insert blank value cuvette see sample preparation into the cell compartmentcell compartment Close the cell compartment Touch Zero 4 Insert the sample cuvette containing the prepared sample into the cell compartment Close the cell compartment Touch Read The result is displayed Note Analysis of additional samples Repeat working procedure from point 4 The prepared blank value solution can be used for the complete series of measurements 2 10 1 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 41 Working procedures 2 11 Vicinal diketones diacetyl 2 3 pentanedione The metabolic processes of yeast produce 2 acetolactate and 2 acetohydroxibutyrate during fermentation These are oxidised to the vicinal diketones diacetyl 2 3 butanedione and 2 3 pentanedione Diacetyl can however also occur as a characteristic metabolic product of certain microorgan
6. hydrochloric acid 5 1 V V e Solution 2 Dissolve 120 mg iron II sulphate FeSO x 7 H20 in 100 ml solution 1 Sample preparation 1 Centrifuge worts and young beers for 10 min at 3000 rpm 2 Pipette 5 ml beer or wort and 5 ml dist H20 into a 50 ml mixing cylinder 3 Pipette 10 ml distilled water blank value into a 50 ml mixing cylinder 4 Use 10 ml dist water to rinse 0 5 g polyamide powder into each mixing cylinder 5 Shake the two mixing cylinders mechanically for 40 min 6 Filter each suspension through a 1 G4 frit rinsing twice with about 20 ml H20 7 Suction dry the frits and polyamide powder Use a spatula to transfer each residue to a test tube rinsing the final traces into each test tube with 15 ml of solution 1 8 Add 0 5 ml of solution 2 and heat both test tubes for 30 min in a bath of boiling water stir well with a glass rod for the first 5 min 9 Remove the glass rod rinse with a little of solution 1 bring the test tubes to 20 C and make each one up to 25 ml with solution 1 10 Measure the absorbance of the solution ina 10 mm rectangular cuvette at 550 nm against a similarly treated blank value solution 10 ml dist water instead of beer Results The result is expressed in mg l without decimal places Accuracy r 9 Standard values 50 70 mg l depending on the raw materials and technical measures correspondingly lower after stabilisation with PVPP Literature MEBAK Brautechnisc
7. solution as described in the working procedure 2 Select Stored Programs in the Main Menu Select test number 810 3 Insert cuvette containing phosphate buffer into the cell compartment Close the cell compartment Touch Zero 4 Insert blank value cuvette containing the prepared iodine blank on AU solution see sample preparation into the cell compartment Close the cell compartment Touch Read Display E1 5 Insert the sample cuvette containing the prepared sample into the cell compartment Close the cell compartment Touch Read Display E2 6 Introduce 0 5 ml 0 02N iodine solution into sample cuvette Mix the contents immediately with plastic spatula and after 30 sec insert the cuvette into the cell compartment close the cover and touch Read The result is displayed Note Analysis of additional samples Repeat working procedure from point 4 The prepared iodine blank solution can be used for the complete i Uv VIS Se 810 Photom iod sample IS DO series of measurements 0 60 23 SEP 2005 12 43 24 Min Options 2 8 1 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 34 Working procedures 2 9 Thiobarbituric acid number TAN The thiobarbituric acid number is a sum parameter for the
8. thermal effects on malt and wort It is a parameter that apart from 5 hydroxymethylfurfural HMF covers a large number of products of the Maillard reaction and other organic compounds Principle The test sample reacts with a solution of thiobarbituric acid and acetic acid and the resulting yellow colour is measured with the help of a spectrophotometer Fields of application Beer wort congress wort or malt extract Measuring range 0 100 Accessories e Water bath 70 C e Brown test tubes with ground glass stoppers 20 ml or 25 ml e Spectrophotometer 448 nm e 10mm rectangular cuvettes OS grade Reagents e Acetic acid 90 Dilute 225 g 100 acetic acid glacial acetic acid with H20 to 250 g e Thiobarbituric acid 0 02 mol l Dissolve 0 288 g 2 thiobarbituric acid M 144 15 g mol in a 100 ml measuring flask with 90 acetic acid by heating in a water bath Cool to 20 C then make up to the mark with 90 acetic acid Prepare freshly each day e Kieselguhr Sample preparation Note The analysis procedure is empirical and should therefore be adhered to exactly 1 Clarify turbid test solutions by filtration over kieselguhr 2 Dilution e Dilute worts and beers 10 fold with H2O e Dilute congress worts 5 fold with H20 3 Blank value a Add 5 ml 90 acetic acid to 10 ml diluted sample shake and proceed as for the main value 35 Working procedures 4 Main value a Add 5 ml thiobarbituric acid to
9. u Working procedures Note Analysis of additional samples Repeat working procedure from point 4 2 9 1 1 Executing the test with the sipper modulel Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 2 9 2 Procedure for measuring thiobarbituric acid number in congress wort Stored Programs Select by Program Number Options 812 TAN c wort 23 0 26 5 y Options 1 Prepare samples and blank value solution as described in the working procedure 2 Select Stored Programs in the Main Menu Select test number 812 3 Insert zero value cuvette containing distilled water into the cell compartment Close the cell compartment Touch Zero 4 Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Read Display E1 5 Insert the sample cuvette containing the prepared sample into the cell compartment Close the cell compartment Touch Read The result is displayed Note Analysis of additional samples Repeat working procedure from point 4 37 Working procedures 2 9 2 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Ins
10. 2 After the carbon dioxide has been expelled pipette 10 ml beer into a test tube with a glass stopper then tilt the tube slightly and add 0 25 ml 0 005M DPI solution 3 Close the test tube immediately and invert it twice to mix the contents starting the stopwatch after the first inversion 4 Immediately fill a 10 mm rectangular cuvette with the mixture 60 sec after adding the reagent measure the absorbance at 520 nm against a blank value solution decarbonated beer without added reagent Results The results are expressed as the proportion of the sample in that was reduced by 10 ml beer in 60 sec Accuracy Ver 1 Standard values gt 60 very good 50 60 good 45 50 satisfactory lt 45 poor Literature MEBAK Brautechnische Analysenmethoden Ath Edition 2002 Volume II pp 104ff 2 3 1 Procedure for measuring reducing power Stored Programs r A g 1 Prepare samples as described in the working procedure 804 Reducing power 640 Selenium 2 Select Stored Programs in the Main Menu Select test number 804 3 Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Zero 4 Insert the sample cuvette containing the prepared sample into the cell compartment and close the cell compartment After 60 re lle sec touch Read The result is displayed 16 Working procedures Note Analysis of additional samples Repeat working procedure from point 3 In o
11. D LANGES UNITED FOR WATER QUALITY DOC022 52 00730 SEP05 Supplementary Software LZV 570 Brewery Analysis DR 5000 User Manual 09 2005 edition1 Hach Lange GmbH 2005 All rights reserved Printed in Germany ck 09 05 edition 1 Table of Contents section 1 General Information ken oe eeseaae te etienne ne dire enna dled ass 5 Ved SatSty Ta Le BLEUE 0 senari E E E EE O 5 T11 USE OF Hazard Information u nee ae einen 5 12 NS UA Lilo RD HERE DEHEEBE E E 5 1 8 Important information about the manual susesi en aE E I rte Dean dE 6 1 3 1 Chemical and Biological Safety ur Hr Eee innen Aenean 6 1 4 Introduction u cab ee ea nn ee een 7 1 5 selecting amp stored Test ea a ara ner RR RER eher 7 1 6 List of abbreviations mossie nn enaren av ae ana ann Da bodman a Erna EIER aed Ehe 7 1 7 Literature an en AR RS Re ee en E 8 Section 2 Working procedures eascann 2 200 essen 9 2 1 Bitter units EBC method E ee etant nement 9 2 1 1 Procedure for measuring bitter units in beer ss 10 2 1 1 1 Executing the test with the sipper module ss 10 2 1 2 Procedure for measuring bitter units in wort ii 11 2 1 2 1 Executing the test with the sipper module ss 11 2 2 Total polyphenols EBC method sise 12 2 2 1 Procedure for measuring total polyphenols ss 13 2 2 1 1 Executing the test with the sipper module ss 14 2 3 Reducing power spectrophotometric method sis 15 2 3 1 Procedure for measuring reducing Power 2 004400 He
12. Executing the test with the sipper module nennen 41 Table of Contents 2 11 Vicinal diketones diacetyl 2 3 pentanedione aaa 42 2 11 1 Procedure for measuring vicinal diketones nn 44 2 11 1 1 Executing the test with the sipper module nennen 44 PE IP AI WOM RER ER RS EEE A ET 45 2 12 1 Procedure for MEasuring WOM 2425 anime einen een panscacnianenasapapsh datas OE 46 2 12 1 1 Executing the test with the sipper module 2444444440nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnennnnnnnennn 47 Section 3 Replacement Parts ccccccecceeccceeencecee cece eee eeeeeeeeaaaaeeeeeeeeeeeeeeececccccaeeeeeeeeeeeeseseececicneeeeeeeeeeeeeteees 49 Section 4 How To Order 444444444444444HHnnnnnnnnnnennnnnnnnnnnnnnnnnnnnneneennnnnnnnnnnnnnnnnnnrreeennnnnssnnnnnnnnnnnnrr ern nn 51 Section 1 General Information 1 1 Safety Information Before you install the software you should read this manual thoroughly Take note of all information labelled Danger or Note Besides the instructions in this manual users must comply with the national general safety and accident prevention regulations of the country in which the instrument is used 1 1 1 Use of Hazard Information DANGER Indicates a potentially or imminently hazardous situation which if not avoided could result in death or serious injury Important Note Information that the user needs to take into account when handling the instr
13. K Brautechnische Analysenmethoden Ath Edition 2002 Volume II pp 107ff 2 2 1 Procedure for measuring total polyphenols 1 Prepare samples and blank value solutions as described in the working procedure 2 Select Stored Programs in the Main Menu Select test number 802 3 Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Zero 4 Insert the sample cuvette containing the prepared sample into the cell compartment and close the cell compartment Touch Read The result is displayed Select by Program Number Options Note Analysis of additional samples Repeat working procedure from point 3 In other words each sample has to have its own specific blank 802 Total polyphenols UV vis 600 nm valie Soliton 49 5 om n Phenols 23 SEP 2005 12 16 49 A Options 13 Working procedures 2 2 1 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 14 Working procedures 2 3 Reducing power spectrophotometric method Reducing power is a measure of the rapidly reducible substances present in beer Reductones are found in relatively small amounts in beer but are of considerable significance for the chemicophysical and biological stability of beer as well
14. as proved to be the best method of identifying malt batches that will impart the undesirable smoky taste and of determining the extent to which tank beer and beer that has gone through the filling stage is affected Principle The phenol fraction obtained with steam reacts in an alkaline environment with 4 amino 2 3 dimethyl 1 phenyl 3 pyrazolin 5 one 4 aminophenazone and the oxidising agent potassium hexacyanoferrate lll to form a colour substance which can be measured with a spectrophotometer after being extracted with chloroform Fields of application Malt beer Measuring range 0 20 mg kg Remarks Wheat beers cannot be analysed by this method because the activity of the top fermenting yeast results in the presence of a considerable amount of steam volatile phenols which do not however impart a smoky taste Accessories e DLFU mill aperture 1 mm e Steam distillation unit e Separating funnels 1 e Spectrophotometer 460 nm e 40mm rectangular cuvette OS grade Reagents e Chloroform ultrapure e Silicone antifoam emulsion e Phosphoric acid conc d 1 71 e Copper sulphate CuSO x 5 H20 10 e Ammonium chloride 5 e 4 Amino 2 3 dimethyl 1 phenyl 3 pyrazolin 5 one 2 prepare freshly each day 29 Working procedures 30 e Potassium hexacyanoferrate lll K Fe CN 8 prepare freshly each day e Phenol standard solution Dissolve 1 000 g phenol in H20 giving 1000 ml 1ml Img The
15. bitter units in wort Stored Programs Select by Program Number Options 275 nm 47 8 sunon 23 SEP 2005 12 15 25 A Options 1 Prepare samples as described in the working procedure 2 Select Stored Programs in the Main Menu Select test number 803 3 Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Zero 4 Insert the sample cuvette containing the prepared iso octane into the cell compartment and close the cell compartment Touch Read The result is displayed Note Analysis of additional samples Repeat working procedure from point 4 2 1 2 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 11 Working procedures 2 2 Total polyphenols EBC method Principle Polyphenols react with iron IIl ions in an alkaline solution to form coloured iron complexes the resulting brown colour is measured with a spectrophotometer Fields of application Beer worts Measuring range 0 800 mg l Accessories e Centrifuge e Spectrophotometer 600 nm e 10mm rectangular cuvette OS grade Reagents e Carboxymethylcellulose ethylenediaminetetracetic acid solution CMC EDTA Na a Weigh out 10 g CMC low viscosity and 2 g EDTA Na b Disso
16. d then after the final measurement the result 8 The FAN result is displayed in mg l Note Analysis of additional samples Repeat working procedure from point 7 Working procedures 2 6 3 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 2 6 4 Procedure for measuring free amino nitrogen FAN in dark beers Stored Programs 200 Formaldehyde Cancel Select by Number Program Options 1 Prepare three blank value solutions three standard solutions and three samples as described in the working procedure 2 Select Stored Programs in the Main Menu Select test number 817 3 Insert zero value solution distilled water into the cell compartment close the cover and touch Zero 4 Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Read Display E1 Note Repeat the procedure with blank value cuvettes 2 and 3 Display E2 and E3 5 Insert standard cuvette see sample preparation into the cell compartment Close the cell compartment Touch Read Display E4 Note Repeat the procedure with standard cuvettes 2 and 3 Display E5 and E6 6 Insert correction cuvette see sample preparation into the cell compartment Close the cell compart
17. de info hach lange co uk www hach lange co uk Information Required e Hach account number if available e Billing address e Your name and phone number e Shipping address e Purchase order number e Catalog number e Brief description or model number or series production number e Quantity 51 How To Order 52
18. dine solution 0 02N prepare freshly each day from the stock solution Phosphate buffer solution 0 1M pH 3 5 adjust the pH of a 0 1M KH PO solution to 3 5 with 0 1M phosphoric acid Sample preparation 1 Pipette 10 0 ml centrifuged wort or carbon dioxide free beer into a centrifuge tube 2 Add 40 0 ml ethanol and shake mechanically for 10 min 3 Centrifuge for 5 min at 2500 rpm 4 Carefully decant as much of the clear phase as possible 5 Dissolve residue in 20 0 ml phosphate buffer solution by shaking mechanically for 10 min 6 Centrifuge the solution for 5 min at 2500 rpm 7 Pipette 2 ml of the supernatant liquid and 8 ml phosphate buffer solution into a 40 mm rectangular cuvette and measure at 578 nm against phosphate buffer solution 8 Add 0 5 ml 0 02N iodine solution mix the contents immediately with the plastic spatula then measure after 30 sec 9 lodine blank solution a Pipette 10 ml phosphate buffer solution and 0 5 ml 0 02N iodine solution into a 40 mm rectangular cuvette and mix b Measure absorbance at 578 nm against phosphate buffer solution Results The results are expressed as absorbance to 2 decimal places Accuracy Vcr 3 Standard values lt 0 3 wort Literature MEBAK Brautechnische Analysenmethoden Ath Edition 2002 Volume Il pp 34ff 33 Working procedures 2 8 1 Procedure for measuring photometric iodine sample Stored P era f a LE 1 Prepare samples and iodine blank
19. e standard solutions and three samples as described in the working procedure Select Stored Programs in the Main Menu Select test number 807 Insert zero value solution distilled water into the cell compartment close the cover and touch Zero Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Read Display E1 Note Repeat the procedure with blank value cuvettes 2 and 3 Display E2 and E3 Insert standard cuvette see sample preparation into the cell compartment Close the cell compartment Touch Read Display Ed Note Repeat the procedure with standard cuvettes 2 and 3 Display E5 and E6 Insert the sample cuvette with the first prepared sample into the cell compartment Close the cell compartment Touch Read Display E7 Note Repeat the procedure with sample cuvettes 2 and 3 Display E8 and then after the final measurement the result The FAN result is displayed in mg l Note Analysis of additional samples Repeat working procedure from point 6 2 6 1 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 24 Working procedures 2 6 2 Procedure for measuring free amino nitrogen FAN in light beer Stored Programs DAV 5 00m PA phy
20. ength Multi Wavelength Wavelength Scan Time Course System es Recall Instrument Checks Data Setup 1 6 List of abbreviations General Information The LZV 570 Supplementary Software for Brewery Analysis is a collection of all spectrophotometric applications that are of relevance for brewery analysis The working instructions are taken from the MEBAK manuals Most of the procedures are from the 4th edition 2002 For many analyses the sipper module can be used to carry out the tests more conveniently 1 Select Stored Programs in the Main Menu An alphabetically sorted list of all available tests is displayed 2 Select a test by touching the corresponding line Note Use the scroll bar to run quickly through the list Note If you already know the number of the desired test touch Select by Number Use the alphanumeric keypad to enter the test number and confirm your input by touching OK 3 Touch Start to start the test program General information Unless otherwise indicated reagents should be analytical grade Unless otherwise indicated solutions are aqueous dist H O distilled or demineralised water sec seconds min minutes h hours SD standard deviation r reproducibility R comparability Ve variation coefficient General Information 1 7 Literature MEBAK Brautechnische Analysenmethoden Analysis methods for the brewing industry Collected methods of the Mitteleur
21. escribed in the working procedure 2 Select Stored Programs in the Main Menu Select test number 806 3 Insert blank value cuvette distilled water into the cell compartment Close the cell compartment Touch Zero 4 Insert the sample cuvette containing the prepared sample into the cell compartment and close the cell compartment Touch Read The result is displayed Note Analysis of additional samples Repeat working procedure from point 4 2 5 1 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 21 Working procedures 2 6 Free amino nitrogen ninhydrin method based on EBC method Principle The test solution is heated with ninhydrin at pH 6 7 and the resulting colour is measured at 570 nm The method covers amino acids ammonia and also the terminal alpha amino groups of peptides and proteins Proline is partially detected at the wavelength used The method is not specific for alpha amino nitrogen because gamma amino butyric acid which occurs in worts also reacts with ninhydrin to produce a colour Fields of application Beer worts Measuring range 0 400 mg l Accessories e Test tubes with ground glass stoppers 16 x 150 mm e Variable pipette 1 0 5 0 ml BBP 065 Pipette tips for pipette BBP 068
22. he Analysenmethoden Ath Edition 2002 Volume II pp 109ff Working procedures 2 4 1 Procedure for measuring anthocyanogens Stored Programs 1 Prepare samples as described in the working procedure 2 Select Stored Programs in the Main Menu Select test number 805 3 Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Zero 4 Insert the sample cuvette containing the prepared sample into the cell compartment and close the cell compartment Touch ee E Read The result is displayed Note Analysis of additional samples Repeat working procedure from point 4 550 nm 23 SEP 2005 12 37 44 a Options 2 4 1 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 19 Working procedures 2 5 Beer colour spectrophotometric EBC method Principle This method is designed to eliminate subjective effects attributable to the human eye as well as differences in the colour impression when the beer samples are compared with the colour card This method is an official reference method The absorbance is measured in a 10 mm rectangular cuvette at a wavelength of exactly 430 nm The colour in EBC units is obtained by converting with a suitable factor Fields of ap
23. ifuge tube and shake mechanically for 30 min at optimal mixing intensity 39 Working procedures 40 6 Separate the phases and break the emulsion by centrifuging for 5 min at 3000 rpm 7 Use a pipette to draw off and discard the bottom aqueous phase Add sodium sulphate to the iso octane phase until the phase clarifies after being shaken vigorously for a short time 8 Pipette 10 ml of the iso octane phase into a 25 ml mixing cylinder 9 Add 10 ml acidic methanol solution and mix the contents of the cylinder by inverting it 100 times 10 Pipette 5 ml of the supernatant clear iso octane phase into a 25 ml measuring flask 11 Make up to the mark with alkaline methanol solution and mix 12 Measure the absorbance of the iso octane solution at 255 nm and 360 nm against a blank value solution 13 Preparation of the blank value solution a Pipette 5 ml iso octane into a 25 ml measuring flask b Fill up to the mark with alkaline methanol solution and mix Results The result is expressed in mg l without any decimal places Accuracy Ver 5 Standard values Beer 10 40 mg l iso a acids depending on type and origin lt 2mg l a acids Wort 15 50 mg l iso a acids depending on the beer and the level of bitter substance utilisation 1 15 mg l a acid depending on degree of isomerisation Literature MEBAK Brautechnische Analysenmethoden Ath Edition 2002 Volume II pp 116ff Working procedures 2 10 1 Procedure
24. ine 4 4 disulphonic acids Ferrozin to form a violet coloured complex with a very high molar absorbance coefficient Trivalent iron must be reduced to the divalent form before the determination is carried out The colour intensity is measured with a spectrophotometer Measuring range 0 1 mg l Accessories e Analytical balance readable to 0 1 mg e Pipettes 0 1 ml 2 ml 5 ml e Spectrophotometer 560 nm e 40mm rectangular cuvette OS grade Reagents Prepare all solutions with iron free H20 e Buffer solution pH 4 3 Dissolve 75 g ammonium acetate and 150 g conc acetic acid in about 800 ml H20 check the pH and make up to 1 I e Ferrozin reagent Dissolve 0 257 g Ferrozin or Ferrospectral in 50 ml buffer the solution remains stable for 2 weeks e Ascorbic acid 2 5 Prepare freshly each day e Hydrochloric acid conc e Iron III standard solution for obtaining the calibration curves Dissolve 863 4 mg ammonium iron IIl sulphate NH4Fe SO gt x 12 H20 in H20 in a 1 measuring flask Add 0 1 ml conc hydrochloric acid and make up to the mark with H20 Dilute 50 ml of this solution with H20 to 1 to obtain a standard solution containing 5 mg ml Fe3 Sample preparation 1 Expel carbon dioxide from beer and allow the foam to completely collapse 2 Pipette 40 ml beer 2 ml Ferrozin reagent and 1 ml ascorbic acid solution into a 50 ml measuring flask 3 Make up to the mark with H20 45 Working proced
25. isms When the threshold value is exceeded the beer acquires an off flavour The photometric determination method is often used in preference to the gas chromatographic method in operational checks because it can be carried out quickly and without the need for expensive apparatus Unfortunately it is not capable of differentiating between diacetyl and pentanedione Principle The basis of the method is the reaction of diacetyl or 2 3 pentanedione with 1 2 phenylenediamine to form 2 3 dimethylquinoxaline which exhibits specific absorbance at 335 nm Fields of application Beer Measuring range 0 1 mg kg Accessories e Macro version of apparatus for nitrogen determination with heating jacket for example from Schott The accompanying cooler may need to be replaced by a larger one if the distillate is not cooled sufficiently Other similar units for example from B chi are equally suitable e Spectrophotometer 335 nm e 20mm rectangular cuvettes QS grade Reagents e Hydrochloric acid 4N e 1 2 Phenylenediamine 1 in 4N hydrochloric acid Prepare the solution freshly on the day when it is needed and keep it is a dark place 1 2 Phenylenediamine is toxic and allergenic handle it carefully and wear gloves while working e Antifoam emulsion free of diketones Sample preparation 1 Introduce 100 g beer from which the carbon dioxide has not been removed into a preheated distillation apparatus 2 Add one drop of
26. lve these substances in about 500 ml H O while stirring When they are completely dissolved fill up to 1 1 with H20 If necessary clarify by centrifuging e Ammonium iron Ill citrate 3 5 a Dissolve 3 5 g ammonium iron IIl citrate green 16 Fe in H20 and make up to 100 ml The solution must be completely clear It remains stable for about 1 week b Ammonia dilute Dilute 1 part concentrated ammonia d 0 91 with 2 parts H20 Sample preparation 1 Shake beer to expel carbon dioxide 2 Clarify cloudy wort or beers by centrifuging 3 Mix 10 ml test solution and 8 ml CMC EDTA solution thoroughly in a 25 ml measuring flask 4 Add 0 5 ml iron IIl solution and mix thoroughly 5 Add 0 5 ml dilute ammonia solution and mix thoroughly 6 Make up to 25 ml with H20 and mix 7 Wait 10 min then measure the absorbance in a 10 mm rectangular cuvette at 600 nm against a blank sample 12 Working procedures 8 Blank value a Introduce 10 ml sample expel carbon dioxide from beer by shaking clarify turbid wort or beer by centrifuging into a 25 ml measuring flask b Add 8 ml CMC EDTA solution and mix thoroughly c Add 0 5 ml dilute ammonia solution and mix thoroughly d Make up to 25 ml with H20 and mix again Note Mix thoroughly after adding each individual solution Result The result is expressed in mg l without any decimal places Accuracy SD 9 Standard values Beer 150 200 mg l Literature MEBA
27. ment Touch Read Display E7 Note Repeat the procedure with correction cuvettes 2 and 3 Display E8 and E9 7 Insert the sample cuvette with the first prepared sample into the cell compartment Close the cell compartment Touch Read Display E10 Note Repeat the procedure with sample cuvettes 2 and 3 Display E11 and then after the final measurement the result 27 Working procedures 817 FAN dark beer UV VIS lt lt 570 nm 8 The FAN result is displayed in mg l 1 0 2 Note Analysis of additional samples Repeat working procedure from point 7 26 SEP 2005 10 50 13 2 6 4 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 28 2 7 Steam volatile phenols Working procedures The degree of fumigation of whisky malts is determined by analysing steam volatile phenols In the beer industry small amounts of smoke dried malts are used to produce Rauchbiere smoked beers a speciality of Franconia Technical problems during kilning can impart a smoky taste to malts that are intended for the production of normal beers This taste is carried through into the finished product resulting in complaints from consumers Besides organoleptic checks spectrophotometric determination of the steam volatile phenols h
28. ne content Literature MEBAK Brautechnische Analysenmethoden Ath Edition 2002 Volume Il pp 134ff 43 Working procedures 2 11 1 Procedure for measuring vicinal diketones Stored Programs F A J 1 Prepare samples and blank value solution as described in the papiengi pA working procedure 2 Select Stored Programs in the Main Menu Select test number 815 3 Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Zero 4 Insert the sample cuvette containing the prepared sample into RARE ans the cell compartment Close the cell compartment Touch Read The result is displayed Note Analysis of additional samples Repeat working procedure from TE point 3 815 Yicinal diketones UV VIS O 335 nm 0 620 ix 26 SEP 2005 10 45 47 a Options 2 11 1 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 44 2 12 Iron Working procedures Iron in beer may originate from raw materials filter aids apparatus pipes or cans or beer foam stabilising agents Iron has a disadvantageous effect on colloidal stability taste and the gushing tendency of the beer Principle Divalent iron reacts with the disodium salt of 5 6 diphenyl 3 2 pyridyl 1 2 4 triaz
29. ning the calibration curve The factor 1 0 037 is an empirical variable and has to be individually determined from a calibration line The factor is the gradient of the calibration line Pipette 40 ml beer into each of four 50 ml measuring flasks Pipette respectively 0 40 ml 0 80 ml 1 60 ml and 3 20 ml iron standard solution 5 mg Fe3 ml into the measuring flasks Add 2 ml Ferrozin reagent and 1 ml ascorbic acid solution to each measuring flask Make up to the mark with H20 Measure the absorbance of the solution in a 40 mm rectangular cuvette at 560 nm against the corresponding blank value solution Blindwert messen Deduct the absorbance of the sample from the absorbance values of the standard solutions 47 Working procedures 48 Section 3 Replacement Parts Description Cat No Macro cuvette OG grade path length 20 mm LZP331 Cuvette set path length 1 cm matched pair 2095100 Cuvette QS grade path length 10 mm 2624410 Pour through cuvette QS grade path length 10 mm fill height 10 mm total height 40 mm LZV510 49 Replacement Parts 50 Section 4 How To Order Orders Repair service Please contact your representative HACH LANGE GMBH HACH LANGE LTD Willst tterstra e 11 Pacific Way D 40549 D sseldorf Salford Tel 49 0 2 11 5288 0 Manchester M50 1DL Fax 49 0 2 11 5288 143 Tel 44 0 161 8 72 14 87 info hach lange de Fax 44 0 161 8 487324 www hach lange
30. nne nn nennen nenn 16 2 3 1 1 Executing the test with the sipper module 4444440sasssnnnnssnnnnnnnnnnnnnnnnnnnnnnnnnnennnnnen nennen 17 2 4 Anthocyanogens Harris and Ricketts method u 2200er 17 2 4 1 Procedure for measuring anthocyanogens sie 19 2 4 1 1 Executing the test with the sipper module ss 19 2 5 Beer colour spectrophotometric EBC method issus 20 2 5 1 Procedure for measuring beer colour 4 een 21 2 5 1 1 Executing the test with the sipper module 4444440ssssnnnnssseennnnnnnnnnnannnnnnnnnnnennnnnennnnnnnen 21 2 6 Free amino nitrogen ninhydrin method based on EBC method usssssnnnnnensnennnnennnnnnnnnennnn nennen nn 22 2 6 1 Procedure for measuring free amino nitrogen FAN in light worts cceeeeeeesenneeeeeeeeneeeeeeeeeneeeeeeeeaes 24 2 6 1 1 Executing the test with the sipper module 2 ee eee cee eeeeeeeceecece eee eeeeeeeeeeeeeecaeaeeeeeeeeeeeeeeteeenneaeees 24 2 6 2 Procedure for measuring free amino nitrogen FAN in light beer ee eeeeeeeeneeeeeeeeeneeeeeeeeeeeeeeeeeaes 25 2 6 2 1 Executing the test with the sipper module o oo eee eee eeeeeeeeeeeeceeeeeeeeeeeeeeeeeeeecaeeeeeeeeeeeeeteeteeeeneaeees 25 2 6 3 Procedure for measuring free amino nitrogen FAN in dark wortS_ uussnsssnnnnennsnnnnnnennennnnnennnn nennen 26 2 6 3 1 Executing the test with the sipper module 444444sssssnnnn
31. o the mark with chloroform Working procedures m Measure the chloroform extract prepared distillate in a 40 mm rectangular cuvette at 460 nm against a blank value solution obtained by following the above procedure but using 300 ml H O instead of the distillate 3 Calibration values a Carry out steam distillation on phenol standard solutions with concentrations between 0 02 and 0 1 mg l use 300 ml then proceed as described above Results The results are expressed in mg kg to two decimal places or in mg l in the case of beer Accuracy Vc 5 repeat error Required values Malts lt 0 2 mg kg no smoky taste to be expected Beers lt 0 03 mg l negligible effect in most cases The intensity of the smoky taste is partly dependent on the composition of the beer The specified lower limit therefore only applies with reservations Literature MEBAK Brautechnische Analysenmethoden 3rd Edition Volume 2 7 1 Procedure for measuring steam volatile phenols Stored Programs Select by Number Program Options 1 Prepare the samples and blank value solution as described in the working procedure 2 Select Stored Programs in the Main Menu Select test number 809 3 Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Zero 4 Insert the sample cuvette containing the prepared sample into the cell compartment and close the cell compartment To
32. octane extract in a 10 mm rectangular cuvette at 275 nm against iso octane of the same quality blank value Working procedures Results Bitter units BU without any decimal places Accuracy Vor 2 4 Ver 6 5 Standard values Beer 10 40 BU depending on type and origin Wort 20 60 BU depending on beer and utilisation of bitter substances Literature MEBAK Brautechnische Analysenmethoden Ath Edition 2002 Volume II pp 114ff 2 1 1 Procedure for measuring bitter units in beer Stored Programs Benzotriazole Select by Program Number Options 275 nm ZI ur 23 SEP 2005 12 14 42 P a Exit Options 1 Prepare samples as described in the working procedure 2 Select Stored Programs in the Main Menu Select test number 801 3 Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Zero 4 Insert the sample cuvette containing the prepared iso octane into the cell compartment and close the cell compartment Touch Read The result is displayed Note Analysis of additional samples Repeat working procedure from point 4 2 1 1 1 Executing the test with the sipper module 10 Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 Working procedures 2 1 2 Procedure for measuring
33. op ischen Brautechnischen Analysenkommision Central European commission for brewery analysis MEBAK Published by the Chairman Dr Heinrich Pfenninger Publishing house of the MEBAK D 85350 Freising Weihenstephan 4th Edition 2002 Section 2 Working procedures 2 1 Bitter units EBC method Principle The bitter substances mainly iso a acids are extracted from the acidified sample with iso octane and the concentration in the extract is determined with a spectrophotometer Fields of application Beer worts Measuring range 20 60 BU Accessories e Centrifuge tubes with solvent tight stoppers 35 ml e Glass beads e Shaker e Centrifuge 3000 rpm e Spectrophotometer 275 nm e 10mm rectangular cuvette QS grade Reagents e Hydrochloric acid 6N e Iso octane 2 2 4 trimethylpentane spectroscopically pure absorbance measured in 10 mm rectangular cuvette QS grade at 275 nm against H20 lt 0 010 for example Uvasol Sample preparation 1 Clarify wort and cloudy beer by centrifuging at 3000 rpm for 15 min do not filter sample 2 Expel carbon dioxide from sample without losing any foam 3 Bring the sample to 20 C and pipette 10 ml 5 ml wort 5 ml dist H O into a centrifuge tube 4 Add 0 5 ml 6N hydrochloric acid 20 ml iso octane and 3 glass beads 5 Close centrifuge tube and shake mechanically for 15 min at 20 C 6 Centrifuge for 3 min at 3000 rpm 7 Measure the absorbance of the iso
34. pectrophotometer 15 3 3 Installation Sipper Module page 133 25 Working procedures 2 6 3 Procedure for measuring free amino nitrogen FAN in dark worts Stored Programs 817 FAN dark beer Select by Program Cancel Number Options 816 FAN dark wort 200 26 SEP 2005 10 48 10 26 Prepare three blank value solutions three standard solutions and three samples as described in the working procedure Select Stored Programs in the Main Menu Select test number 816 Insert zero value solution distilled water into the cell compartment close the cover and touch Zero Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Read Display E1 Note Repeat the procedure with blank value cuvettes 2 and 3 Display E2 and E3 Insert standard cuvette see sample preparation into the cell compartment Close the cell compartment Touch Read Display E4 Note Repeat the procedure with standard cuvettes 2 and 3 Display E5 and E6 Insert correction cuvette see sample preparation into the cell compartment Close the cell compartment Touch Read Display E7 Note Repeat the procedure with correction cuvettes 2 and 3 Display E8 and E9 Insert the sample cuvette with the first prepared sample into the cell compartment Close the cell compartment Touch Read Display E10 Note Repeat the procedure with sample cuvettes 2 and 3 Display E11 an
35. plication Plant wort beer liquid malt substitutes of all kinds Measuring range 0 20 units Accessories e Spectrophotometer 430 nm 0 5 nm e 10mm rectangular cuvettes OS grade Sample preparation 1 Dilute the sample so that the absorbance is within the linearity range of the spectrophotometer 2 Filter the sample through a membrane filter Filtration is not necessary if the turbidity of the diluted sample is less than 1 EBC turbidity unit 3 If necessary clarify the sample by adding 0 1 kieselguhr and filtering before the membrane filtration is carried out 4 Measure the absorbance A at 430 nm against dist water blank value Results The results are expressed in EBC units to 2 significant decimal places Interferences A spectrometric absorbance curve does not reflect the colour impression of the human eye because light of the same intensity does not have a uniform effect on the eye in different parts of the spectrum In addition the absorbance curves at 430 nm are very steep so slight measurement errors may occur Moreover there are differences when light beers are compared with diluted dark beers Literature MEBAK Brautechnische Analysenmethoden Ath Edition 2002 Volume II pp 88ff 20 Working procedures 2 5 1 Procedure for measuring beer colour Stored Programs Select by Number 806 Beer color 28 SEP 2005 14 21 36 Program Options 430 nm Options 1 Prepare samples as d
36. rin 808 FAN light beer Cancel Select by Number 808 FAN light beer 181 23 SEP 2005 12 41 37 Program Options mg l FAN 570 nm Prepare three blank value solutions three standard solutions and three samples as described in the working procedure Select Stored Programs in the Main Menu Select test number 808 Insert zero value solution distilled water into the cell compartment close the cover and touch Zero Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Read Display E1 Note Repeat the procedure with blank value cuvettes 2 and 3 Display E2 and E3 Insert standard cuvette see sample preparation into the cell compartment Close the cell compartment Touch Read Display E4 Note Repeat the procedure with standard cuvettes 2 and 3 Display E5 and E6 Insert the sample cuvette with the first prepared sample into the cell compartment Close the cell compartment Touch Read Display E7 Note Repeat the procedure with sample cuvettes 2 and 3 Display E8 and then after the final measurement the result 7 The FAN result is displayed in mg l Note Analysis of additional samples Repeat working procedure from point 6 2 6 2 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 S
37. rts and beers perform three times a Introduce 2 ml of the diluted sample into a test tube b Add 1 ml H20 instead of the colour reagent then proceed as described above c Measure against H O after adding 5 ml dilution solution Results The results are expressed in mg l without decimal places Accuracy r 17 R 28 Standard values Finished wort 12 200 250 mg l Beer 12 100 120 mg l About 220 250 mg l free amino nitrogen should be present in the original wort to ensure satisfactory primary and secondary fermentation Interferences The amino acids are present in very small amounts so contamination must be avoided at all costs The carefully cleaned test tubes should only be touched on the outside Ground glass stoppers etc should be picked up with forceps Literature MEBAK Brautechnische Analysenmethoden Ath Edition 2002 Volume Il pp 62ff Remark The working procedure described below specifies that the blank value solutions standard solution and sample should be measured three times without correction when light beer and wort are analysed In the case of dark beers the working procedure specifies that the blank value solution standard solution correction and sample should be measured three times 23 Working procedures 2 6 1 Procedure for measuring free amino nitrogen FAN in light worts Stored Programs 1 Select by Program Number Options 7 Prepare three blank value solutions thre
38. solution must be clear and colourless Use this solution to prepare dilutions with which to obtain the calibration curve between 0 02 and 0 1 mg l when needed e Ammonia dilute 1 4 Dilute 1 part conc ammonia d 0 91 with 4 parts H20 Sample preparation 1 Steam distillation a a Introduce 50 g coarse malt and 500 ml H O for beer analyses 300 ml into a distillation flask Add 3 ml copper sulphate solution Add phosphoric acid until the pH is less than 4 Add silicone antifoam emulsion Carry out steam distillation until 300 ml have been obtained Colour reaction Add 10 ml ammonium chloride solution to all of the distillate or correspondingly less in the case of genuine smoke dried malts or whisky malts for example 100 ml To prepare a blank value solution use 300 ml H O instead of the distillate and add 10 ml ammonium chloride solution Shake Adjust the pH of the distillate and blank value solution to 10 2 0 1 by adding ammonia Transfer to 1 separating funnels Add 3 ml 4 amino 2 3 dimethyl 1 phenyl 3 pyrazolin 5 one and 3 ml potassium hexacyanoferrate lll to each funnel Shake Leave to stand for 3 min Extract by adding 10 ml chloroform to each funnel and shaking each funnel 3 times 1 min Wait 10 min for phase separation to occur Filter the chloroform extracts through a paper filter into 25 ml measuring flasks Rinse the filters with a little chloroform Fill each flask up t
39. ssseennnnnnnnnnnnnnnnnnnnnnennnnnnen nenn 27 2 6 4 Procedure for measuring free amino nitrogen FAN in dark beers 0 0 ee eeeeeeeeeeneeeeeeeeeneeeeeetenneeeeeeenes 27 2 6 4 1 Executing the test with the sipper module 2 ccc e cece ee eeeeeeeeeececeeeeeeeeeeeeeececceeeeeeeeeeeeetetteeseneeees 28 2 7 Steam Volatil PHEMONS ssnin na ih een u ip 29 2 7 1 Procedure for measuring steam volatile phenols nn 31 2 7 1 1 Executing the test with the sipper module ss 32 2 8 Pihotometrieli dine sample u a need aa nn Eana Na nEs tendent 32 2 8 1 Procedure for measuring photometric iodine sample ssssnssseesenossesnnnnrnnntteeereeretnnnnnnrnenetetnnnnnnnnnnnnee et 34 2 8 1 1 Executing the test with the sipper module si iissisciniiiaineniin nanen eni ekaan aea 34 2 9 Thiobarbiturie acid number TAN sus 2 een ea en ea 35 2 9 1 Procedure for measuring thiobarbituric acid number in beer and wort uuunsssssssennssnnnnnennennnnnnnnen nn 36 2 9 1 1 Executing the test with the sipper modulel uusssssssnnsssennnnnnnnnnnnnnnnnnnnnnnennnnnnennnnnnen 37 2 9 2 Procedure for measuring thiobarbituric acid number in congress wort uueensssssnnennsnnnnnnennennnnnnennnnnnnnn 37 2 9 2 1 Executing the test with the sipper module 444440ssssnnnnssseennnnnnnnnnnnnnnnnnnnnneennnnnen nennen 38 2 10 150 c ds and acids u ee ia AAE EEES 39 2 10 1 Procedure for measuring iso o acids and acids nn 41 2 10 1 1
40. tallation Sipper Module page 133 38 2 10 Iso a acids and a acids Working procedures Principle The bitter substances are extracted from the acidified sample with iso octane Certain substances that cause interference are removed by washing the extract with acidified methanol and the concentrations of iso a acids and a acids are determined by measuring the absorbance in alkaline methanol at 255 nm and 360 nm Fields of application Beer wort Measuring range 0 60 mg l Accessories e Centrifuge tubes with solvent tight screw tops 100 110 ml content e Shaker e Centrifuge 3000 rpm e Spectrophotometer 255 nm and 360 nm e 10mm rectangular cuvettes QS grade Reagents e Hydrochloric acid 6N Iso octane 2 2 4 trimethylpentane of spectroscopic purity e Sodium sulphate anhydrous e Methanol e Hydrochloric acid 4N e Sodium hydroxide 6N carbonate free e Acidic methanol solution Mix 64 ml methanol and 36 ml 4N hydrochloric acid prepare freshly each day e Alkaline methanol solution Take 0 2 ml 6N sodium hydroxide and make up to 100 ml with methanol prepare freshly each day Sample preparation 1 Clarify wort or cloudy beer by centrifuging at 3000 rpm for 15 min do not filter 2 Expel carbon dioxide from beer without losing any foam 3 Bring the sample to 20 C then pipette 50 ml into a centrifuge tube 4 Add 3 mi 6N hydrochloric acid and 25 ml iso octane 5 Close the centr
41. ther words each sample has to have its own specific blank value solution 804 Reducing power UV VIS 520 nm 87 6 23 SEP 2005 12 18 42 2 3 1 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 2 4 Anthocyanogens Harris and Ricketts method Anthocyanogens leucoanthocyanidins are phenolic compounds which are transformed into red anthocyanidins by hot hydrochloric acid The amount and degree of condensation or polymerisation of these compounds influence the formation of colloidal turbidities in beer Stabilisation measures with PVPP correlate with a reduction in the anthocyanogen content Principle The anthocyanogens are adsorbed on polyamide The adsorbate is dissolved in butanol and hydrochloric acid and heated A red solution is formed whose intensity is measured with a photometer Fields of application Beer worts Measuring range 0 100 mg l Accessories e Shaker e Centrifuge e Mixing cylinder with ground glass stopper 50 ml e Frit 1 G4 e Suction flask e Test tubes with ground glass stoppers 30 ml graduations to 25 ml e Vacuum pump e Spectrophotometer 550 nm e 10mm rectangular cuvette OS grade 17 Working procedures 18 Reagents e MN polyamide SC 6 e Solution 1 n butanol 37
42. uch Read The result is displayed 31 Working procedures Note Analysis of additional samples Repeat working procedure from point 4 809 Steam Yolat Phenols UV VIS 460 nm 1 70 mg kg n Phenols 23 SEP 2005 12 42 14 2 7 1 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 2 8 Photometric iodine sample Photometric iodine sample by new method MEBAK from 1993 Principle High molecular dextrins and starches are precipitated by adding ethanol to wort and beer separated by centrifuging and dissolved in a phosphate buffer to which iodine solution is then added Depending on the molecular weight and the degree of branching of the erythrodextrins and starch a red to blue colour appears whose intensity is measured with the help of a photometer Fields of application Wort beer samples whose iodine value is gt 0 8 must be diluted Measuring range 0 1 iodine value Accessories e Centrifuge e Centrifuge tubes with ground glass stoppers 100 110 ml content e Shaker e Pipettes 0 5 ml 2 ml 10 ml 20 ml 40 ml e Spectrophotometer 578 nm e 40mm rectangular cuvette OS grade e Plastic spatula Reagents e Ethanol 95 e Iodine solution 1N stock solution 32 Working procedures lo
43. ument Note Additional operating information for the user 1 2 Installation 1 Touch Instrument Update in the System Check menu 2 Plug the USB memory stick into the USB socket type A of the DR 5000 3 Confirm by touching OK 4 Theconnection is established automatically and the software is updated Touch OK to return to the System Check menu General Information 1 3 Important information about the manual Copyright The copyright to this User Manual remains with the manufacturer The manual contains instructions and notes that may not be fully or partially e duplicated e disseminated e used without authorization for competitive purposes or communicated in any other way 1 3 1 Chemical and Biological Safety DANGER Handling chemical samples standards and reagents can be dangerous Users of this product are advised to familiarize themselves with safety procedures and the correct use of chemicals and to carefully read all relevant Material Safety Data Sheets During the analysis of the sample it may be necessary to use toxic readily flammable or corrosive chemicals e The user must observe all cautionary information printed on the original solution containers and safety data sheet prior to their use e All waste solutions must be disposed in accordance with local and national law 1 4 Introduction 1 5 Selecting a stored test Main Menu Stored Programs User Programs Favorite Programs Single Wavel
44. ures 4 Prepare a blank value solution in exactly the same way but without adding the Ferrozin reagent Prepare a blank value solution for each beer 5 Measure the absorbance of the solution in a 40 mm rectangular cuvette at 560 nm against the corresponding blank value solution Results The results are expressed in mg l to three significant places Accuracy r 0 008 Required value lt 0 200 mg l Literature MEBAK Brautechnische Analysenmethoden 4th Edition 2002 Volume II pp 149ff 2 12 1 Procedure for measuring iron Stored Programs J 1 Prepare samples and blank value solution as described in the working procedure 2 Select Stored Programs in the Main Menu Select test number 818 3 Insert blank value cuvette see sample preparation into the cell compartment Close the cell compartment Touch Zero 4 Insert the sample cuvette containing the prepared sample into cancel ii eae the cell compartment Close the cell compartment Touch Read The result is displayed Note Analysis of additional samples Repeat working procedure from point 3 560 nm mg l Iron 26 SEP 2005 10 50 56 PN Options 46 Working procedures 2 12 1 1 Executing the test with the sipper module Information about the installation module configurations and sample introduction of the sipper module can be found in the user manual of the DR 5000 Spectrophotometer 15 3 3 Installation Sipper Module page 133 Obtai
Download Pdf Manuals
Related Search