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Analytical Guide for Routine Beverage Analysis

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Analytical Guide for Routine Beverage Analysis Table of Contents Introduction Process Critical Parameters in Alcoholic Beverages Organic Acids Important Cations Sugars Metals Titration Parameters Reagent Ordering Table Analytical guide for routine beverage analysis Table of Contents Table of Contents Introduction Process Critical Parameters in Alcoholic Beverages Organic Acids Important Cations Introduction Sugars Process Critical Parameters in Alcoholic Beverages Important Cations Metals Acetaldehyde Ammonia Titration Parameters Alpha-Amino Nitrogen (NOPA) Calcium Reagent Ordering Table Beta-Glucan (High MW) Magnesium Bitterness Potassium Ethanol Sugars Glycerol D-Fructose Total Polyphenol D-Glucose Total Protein (Biuret) D-Glucose & D-Fructose Alpha Amylase D-Glucose & D-Fructose & Sucrose Organic Acids Sucrose Tartaric Acid Metals Acetic Acid Total Iron (Fe) Citric Acid Titration Parameters D-Gluconic Acid pH (colorimetric) D-Isocitric Acid pH and Conductivity by Electro chemistry D-Lactic Acid Free and Total SO2 L-Lactic Acid Total SO2 L-Malic Acid Total Acids (TA) Oxalic Acid Reagent Ordering Table L-Ascorbic Acid Table of Contents Beverage analysis Introduction Process Critical For all beverages, the compositional quality and safety must be monitored The Thermo Scientific™ Gallery™ Discrete Analyzer provides an integrated Parameters in Alcoholic to help track contamination, adulteration and product consistency, and to platform for colorimetric, photometric and electrochemical analyses, which Beverages ensure regulatory compliance from raw ingredients (water, additives and can be run in parallel. Discrete cell technology allows for simultaneous fruits) to the final product. measurement of several different tests for the same sample, eliminating Organic Acids method changeover time. Each individual reaction cell is isolated and Analytes of interest include ions, sugars, organic acids, alcohol, color, temperature-stabilized, thus providing highly controlled reaction conditions. Important Cations metals, protein and enzymes. Analytical testing solutions involved in The Gallery discrete analyzer is able to achieve very low detection levels, beverage analysis encompass several types of chromatographic, elemental and its sophisticated dilution features help to manage a wide concentration Sugars and traditional wet chemistry analysis techniques. range without user intervention. Results are ready within minutes, translating into a remarkable reduction of hands-on time. The wavelength Automated wet chemistry analysis Metals range covers filter configurations from 340 nm up to 880 nm. An optional, Traditional wet chemistry methods include titration, colorimetry and pH integrated Electro Chemical Measurement (ECM) unit supports conductivity and ion-selective measurements, as well as, Flow Injection Analysis (FIA), Titration Parameters and pH measurements over a wide range. or Segmented Flow Analysis (SFA). However, traditional wet chemistry Reagent Ordering Table methods are labor-intensive and time-consuming. Technology comparison Traditional wet chemistry Gallery discrete analyzer platform • mL reagents •Typically single or max • 2-120 µL reagents • Parallel and batch • 50-100 mL samples per test 4 parameters per sample • Max 300 µL per test • Up to 20 parameters per sample • Liters of waste generation •High cost per analysis • Few mL of waste • Low cost per analysis • Multiple instruments • Low throughput – 20-80 •Single platform •High throughput up to 200-350 tests/hr • Labor intensive tests/hr • Easy to operate • Integrated barcode reader for • Sequential or batch • Fully automated samples and reagents Multiparameteranalysis – optimized workflow with the Gallery discrete analyzer Multiple Ready to use Multiple tests Single instrument Turnaround Walkaway sample types reagents per sample multiparameter analysis time solution Range of organic acids Anions: Fluoride, Chloride, Nitrite, Nitrate, Sulfate Ammonia, Barcodes Total Kjeldahl Nitrogen (TKN) Calcium, Magnesium, Potassium Phosphate, Total phosphate pH, Conductivity Alkalinity, Total hardness Free and total cyanide Metals: total iron, Cr(VI)... Wine specific parameters Barcodes Beer specific parameters Cider testing Water and waste water as per regulatory method Table of Contents Beverage analysis Introduction Process Critical Parameters in Alcoholic Beverages Organic Acids Important Cations Sugars Metals Sample preparation Titration Parameters Sample preparation is an important step in beverage analysis, but it’s not always necessary. Some samples (e.g., wine) often require no treatment. With other samples (e.g., juice), sometimes short Reagent Ordering Table centrifugation (e.g., 5 min., 15,000 rpm) is enough to make the sample homogeneous, or extraction, dilution or filtration is sufficient for sample preparation. Typical sample preparation methods are listed below. Sample characteristics Preparation method Liquid, clear, colorless and Use samples directly, or after dilution, into the measuring range of the assay. The Gallery discrete analyzer can perform the dilutions practically neutral automatically. Turbid Use filter or centrifuge. Contains carbon dioxide Degas samples by shaking and filtering with a folder filter paper or in an ultrasonic bath. Contains protein Deproteinize samples with Carrez reagents. Solid or semi-solid, does not Crush or homogenize the samples. Weigh sufficient quantity of the sample in a volumetric flask (take note of the measuring range); contain fat extract with water and filtrate; centrifuge or use Carrez clarification, if necessary. Weigh sufficient quantity of the sample into a volumetric flask (take note of the measuring range); extract with hot water. Solid or semi-solid, contains Cool to allow the fat to separate, make up to the mark, place the volumetric flask in an ice bath for 15-30 min. and filter. fat Discard the first few ml of filtrate, and use the clear supernatant (which may be slightly opalescent) for the assay. Alternatively, clarify with Carrez reagents. Adjust the sample solution to suitable pH by adding Hydrochloric acid (1 M) or potassium hydroxide solution (2 M) and incubate for Needs pH adjustment approx. 15-30 min. Treat sample solution with polyvinylpolypyrrolidone (PVPP) (e.g., 1 g/100 ml sample). Shake the tube vigorously for 5 min., Strongly colored then filter the sample. Download Smart Note: What is Better for Automating Wet Chemical Analysis? Integrated Discrete Analyzer or Flow Analyzers? Table of Contents Acetaldehyde Introduction Process Critical Parameters in Alcoholic Beverages Acetaldehyde is commonly found in food and beverages such as fruits, Table 1. Reagents vegetables, and dairy products. Generally, fruits have more acetaldehyde Maximum Acetaldehyde Reagent Part Number Measuring Range (mg/L) than vegetables and other foods. Eating foods with significant amounts Number of Tests Alpha-Amino Nitrogen (NOPA) of acetaldehyde may increase the risk of cancers of the digestive tract. 984347 250 2 – 500 Beta-Glucan (High MW) 984396 – Some foods are made through fermentation by microorganisms, Acetalldehyde Standard Bitterness such as yeast, fungi or bacteria. Acetaldehyde is a byproduct of fermentation, which means that fermented foods can have high y = 0.939x + 3.3829 Ethanol 2 Linearity 2 –- 500 mg/lmg/L amounts of acetaldehyde. Types of fermented foods that may be high R = 0.9996 600 Glycerol in acetaldehyde include yogurt, vinegar, kombucha, fish products, ) 500 Total Polyphenol fermented mushrooms, fermented soy products, pickled vegetables, canned vegetables and kimchi. 400 Total Protein (Biuret) ed (mg/l 300 Alpha Amylase Acetaldehyde enters the human body when breathing air that contains it, 200 like with cigarette smoke. It can also enter body when you ingest foods Measur 100 or drinks containing acetaldehyde. When drinking alcohol, for example, Organic Acids 0 the body makes acetaldehyde to process the alcohol. Acetaldehyde 0 100 200 300 400 500 600 enters the blood, damaging your membranes and possibly causing scar Important Cations TheorTheoreticaletical mg/L (mg/l) tissue. It may also cause a hangover, and can result in a faster heartbeat, Figure 1: Method performance linearity Sugars a headache or an upset stomach. Samples: Method performance was tested for beer and white wine; Method: Gas Chromatography with Headspace is also used for Metals however, the method can also be applied for other alcoholic beverages, acetaldehyde determination in several food products. Selective citrus fruit juices and vegetable juices. Additional sample preparation may enzymatic reaction followed by a photometric measurement is highly Titration Parameters be necessary to remove interference, especially with colored samples selective and can be automated. Automated photometric measurement like red wine, which needs to be decolorized. Please refer to the sample Reagent Ordering Table is rapid and can measure acetaldehyde down to 2 mg/L. preparation section of the insert for more details. It is recommended to Chemistry: The method is based on the enzyme catalyzed conversion validate the method using spiked samples with a known amount of analyte of acetaldehyde to acetic acid in the presence of NAD. Within that to see the possible matrix effect of the sample. reaction, NAD is reduced to NADH, which causes a spectral shift in the Precision: absorbance of the solution. NADH has a distinct absorbance at 340 nm Table 2. Precision while NAD absorbs at 260 nm. The amount of NADH formed in this Spiked Beer White Wine reaction is stoichiometric with the amount of acetaldehyde.
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