Ripper Procedure for Determining Sulfur Dioxide in Wine: Collaborative Study

Abstract Twenty-three laboratories analyzed 5 replicate wine samples according to a specified version of the Ripper direct iodometric titration for sulfur dioxide. Each sample was analyzed for (A) free S02, (B) total S02, and (C) iodine-reactive substances other than S02. Although variations of A with temperature and of A and B with time of analysis were anticipated, analysis of covariance showed no significant reduction in error when these variables were taken into account. Error did vary with S02 level and wine type, red vs white. Pooled estimates of precision (withinlaboratory error) in mg S02/L wine were, for white wine: (A) 3.3, (B) 10.4, (C) 1.9; for red wine: (A) 3.8, (B) 7.3, (C) 1.9. Pooled estimates of systematic (between-laboratory) error in mg SO2/L wine were, for white wine: (A) 2.7, (B) 16.6, (C) 2.1; for red wine: (A) 4.3, (B) 15.1, (C) 3.0. Although rapid and convenient, the Ripper method is severely limited by poor precision and large systematic error. The Ripper method is not recommended for adoption by the AOAC.

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Determination of Total Carbohydrates in Wine and Wine-Like Beverages by HPLC with a Refractive Index Detector: First Action 2013.12

Journal of AOAC International ◽

10.5740/jaoacint.13-320 ◽

2014 ◽

Vol 97 (2) ◽

pp. 498-505 ◽

Cited By ~ 2

Author(s):

Steve Kupina ◽

Mark Roman ◽

D Anderson ◽

S Bhandari ◽

M S Cardozo ◽

...

Keyword(s):

Refractive Index ◽

Reference Material ◽

Organic Acids ◽

Red Wine ◽

Collaborative Study ◽

Ion Exchange Resin ◽

White Wine ◽

Negative Control ◽

Total Carbohydrates

Abstract An international collaborative study was conducted of an HPLC-refractive index (RI) detector method for the determination of the combined amounts of sugars, glycerol, organic acids, and phenolic compounds in wines and wine-like beverages. Nine collaboratinglaboratories representing major winery, contract laboratories, and government laboratories tested eight different materials as blind duplicates using the proposed method. Sample materials included red and white wines, port, wine cooler, and nonalcoholic wine. One material was a negative control, and one material was a reference material. Samples were either treated with an ion-exchange resin to remove interferingorganic acids prior to analysis or left untreated toinclude organic acids and phenolics. Red wine samples were treated with polyvinylpolypyrrolidone to remove potential interferences from phenolics prior to analysis. The HPLC analyses were performed on a Bio-Rad Fast Acid Analysis Column using RI detection. Reproducibility (RSDR) for untreated samples(sugars + phenolics + organic acids) ranged from 6.6% for Titrivin AA4 reference material to 11.0% for dry red wine. RSDR for treated samples (sugars only) ranged from 6.8% for white zinfandel to 18.9% for dry white wine. RSDR for treatedsamples (sugars only) + glycerol ranged from 6.4% for white zinfandel to 19.8% for dry red wine. Based on these results, the method was adopted as Official First Action status for determination of total carbohydrates in wine and wine-like beverages.

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Determination of Ochratoxin A in Wine and Beer by Immunoaffinity Column Cleanup and Liquid Chromatographic Analysis with Fluorometric Detection: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/84.6.1818 ◽

2001 ◽

Vol 84 (6) ◽

pp. 1818-1827 ◽

Cited By ~ 70

Author(s):

Angelo Visconti ◽

Michelangelo Pascale ◽

Gianluca Centonze ◽

E Anklam ◽

A M Betbeder ◽

...

Keyword(s):

Ochratoxin A ◽

Red Wine ◽

Collaborative Study ◽

White Wine ◽

Fluorometric Detection ◽

Immunoaffinity Column ◽

Relative Standard ◽

Standard Deviations ◽

Liquid Chromatographic

Abstract The accuracy, repeatability, and reproducibility characteristics of a liquid chromatographic method for the determination of ochratoxin A (OTA) in white wine, red wine, and beer were established in a collaborative study involving 18 laboratories in 10 countries. Blind duplicates of blank, spiked, and naturally contaminated materials at levels ranging from ≤0.01 to 3.00 ng/mL were analyzed. Wine and beer samples were diluted with a solution containing polyethylene glycol and sodium hydrogen carbonate, and the diluted samples were filtered and cleaned up on an immunoaffinity column. OTA was eluted with methanol and quantified by reversed-phase liquid chromatography with fluorometric detection. Average recoveries from white wine, red wine, and beer ranged from 88.2 to 105.4% (at spiking levels ranging from 0.1 to 2.0 ng/mL), from 84.3 to 93.1% (at spiking levels ranging from 0.2 to 3.0 ng/mL), and from 87.0 to 95.0% (at spiking levels ranging from 0.2 to 1.5 ng/mL), respectively. Relative standard deviations for within-laboratory repeatability (RSDr) ranged from 6.6 to 10.8% for white wine, from 6.5 to 10.8% for red wine, and from 4.7 to 16.5% for beer. Relative standard deviations for between-laboratories reproducibility (RSDR) ranged from 13.1 to 15.9% for white wine, from 11.9 to 13.6% for red wine, and from 15.2 to 26.1% for beer. HORRAT values were ≤0.4 for the 3 matrixes.

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Determination of Free (pH 2.2) Sulfite in Wines by Flow Injection Analysis: Collaborative Study

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/73.2.223 ◽

1990 ◽

Vol 73 (2) ◽

pp. 223-226

Author(s):

John J Sullivan ◽

Thomas A Hollingworth ◽

Marleen M Wekell ◽

Victor A Meo ◽

Ali Etemad-Moghadam ◽

...

Keyword(s):

Flow Injection ◽

Flow Injection Analysis ◽

Red Wine ◽

Collaborative Study ◽

White Wine ◽

Average Level ◽

Aoac Official ◽

Green Solution ◽

High Degree

Abstract A method for the determination of free sulfite In wine by flow injection analysis (FIA) is described. The method Involves liberation of sulfur dioxide from the wine at pH 2.2, with detection by decolorlzation of a malachite green solution. The method was collaboratively studied, and the results indicated an average reproducibility of 12% for white wine samples (average level 12.1 ppm S02) and 26% for red wine samples (average level 3.1 ppm). When the FIA method was compared to an aeration/oxidation method, the results Indicated a high degree of correlation between the 2 methods. The FIA method has been adopted by AOAC official first action.

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Characterisation of Extracts Obtained from Unripe Grapes and Evaluation of Their Potential Protective Effects against Oxidation of Wine Colour in Comparison with Different Oenological Products

Foods ◽

10.3390/foods10071499 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1499

Author(s):

Giovanna Fia ◽

Ginevra Bucalossi ◽

Bruno Zanoni

Keyword(s):

Antioxidant Activity ◽

Red Wine ◽

Waste Product ◽

Natural Antioxidants ◽

White Wine ◽

Small Scale ◽

Protective Effects ◽

White Wines ◽

Accelerated Oxidation ◽

Wine Colour

Unripe grapes (UGs) are a waste product of vine cultivation rich in natural antioxidants. These antioxidants could be used in winemaking as alternatives to SO2. Three extracts were obtained by maceration from Viognier, Merlot and Sangiovese UGs. The composition and antioxidant activity of the UG extracts were studied in model solutions at different pH levels. The capacity of the UG extracts to protect wine colour was evaluated in accelerated oxidation tests and small-scale trials on both red and white wines during ageing in comparison with sulphur dioxide, ascorbic acid and commercial tannins. The Viognier and Merlot extracts were rich in phenolic acids while the Sangiovese extract was rich in flavonoids. The antioxidant activity of the extracts and commercial tannins was influenced by the pH. In the oxidation tests, the extracts and commercial products showed different wine colour protection capacities in function of the type of wine. During ageing, the white wine with the added Viognier UG extract showed the lowest level of colour oxidation. The colour of the red wine with the UG extract evolved similarly to wine with SO2 and commercial tannins. The obtained results indicated that natural and healthy UG extracts could be an interesting substitute for SO2 during wine ageing.

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Effect of enological treatments on phenolic and sensory characteristics of red wine during aging: Micro-oxygenation, sulfur dioxide, iron with copper and gelatin fining

Food Chemistry ◽

10.1016/j.foodchem.2020.127848 ◽

2021 ◽

Vol 339 ◽

pp. 127848

Author(s):

Natka Ćurko ◽

Karin Kovačević Ganić ◽

Marina Tomašević ◽

Leo Gracin ◽

Michael Jourdes ◽

...

Keyword(s):

Sulfur Dioxide ◽

Red Wine ◽

Sensory Characteristics

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The effects of copigments, sulfur dioxide and enzyme on the mass transfer process of malvidin-3-glucoside using a modelling approach in simulated red wine maceration scenarios

Food and Bioproducts Processing ◽

10.1016/j.fbp.2021.09.001 ◽

2021 ◽

Author(s):

Xin-Ke Zhang ◽

David W. Jeffery ◽

Richard A. Muhlack ◽

Chang-Qing Duan

Keyword(s):

Mass Transfer ◽

Sulfur Dioxide ◽

Transfer Process ◽

Red Wine ◽

Mass Transfer Process ◽

Modelling Approach

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Self-Rated Aversion to Taste Qualities and the PROP Taster Phenotype Associate with Alcoholic Beverage Intake and Preference

Beverages ◽

10.3390/beverages7020037 ◽

2021 ◽

Vol 7 (2) ◽

pp. 37

Author(s):

Gary J. Pickering ◽

Margaret K. Thibodeau

Keyword(s):

Alcohol Consumption ◽

Red Wine ◽

Alcoholic Beverage ◽

Likert Scale ◽

White Wine ◽

Sensory Attributes ◽

Taste Perception ◽

Alcoholic Beverages ◽

Convenience Sample ◽

Beverage Type

Consumers often identify “taste” as an important factor when selecting alcoholic beverages. Although it is assumed that reduced alcohol consumption in PROP super-tasters is due to a greater dislike of the nominally aversive sensations that they experience more intensely (e.g., bitterness) when compared to PROP non-tasters, this question has not been specifically asked to them. Therefore, we examined consumers’ self-reported aversion towards specific sensory attributes (bitter, hot/burn, dry, sour, sweet, carbonation) for four alcoholic beverage types (white wine, red wine, beer, spirits) using a convenience sample of U.S. wine consumers (n = 925). Participants rated 18 statements describing different combinations of sensory attributes and alcoholic beverages on a 5-point Likert scale (e.g., Beer tastes too bitter for me). Individuals who tended to agree more strongly with the statements (i.e., they were more averse; p(F) < 0.05) tended to (i) consume less of all beverage types, (ii) consume a higher proportion of white wine (p(r) < 0.05), and (iii) were more likely to be female or PROP super-tasters. The results suggest that self-reported aversion to specific sensory attributes is associated with not only lower overall intake of alcoholic beverages, but also a shift in the relative proportions of beverage type consumed; a key finding for studies investigating how taste perception impacts alcohol consumption.

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UHPLC/ESI-MS/MS Determination of 187 Pesticides in Wine

Journal of AOAC International ◽

10.5740/jaoacint.15-0265 ◽

2016 ◽

Vol 99 (2) ◽

pp. 539-557 ◽

Cited By ~ 9

Author(s):

Jian Wang ◽

Wendy Cheung

Keyword(s):

Measurement Uncertainty ◽

Electrospray Ionization ◽

Pesticide Residues ◽

Red Wine ◽

White Wine ◽

Tandem Ms ◽

Fast Method ◽

Intermediate Precision ◽

Method Performance ◽

Standard Calibration

Abstract This paper presents an ultra HPLC/electrospray ionization-tandem MS method to determine pesticides in wine. We adopted the quick, easy, cheap, effective, rugged, and safe (QuEChERs) method for extraction and used core-shell column to achieve ultra-HPLC to develop and validate a simple and fast method to analyze 187 pesticide residues in red and white wine samples. Pesticide residues were extracted from wine samples using QuEChERS. Ultra HPLC/electrospray ionization-tandem MS quantification was achieved using matrix-matched standard calibration curves with isotopically labeled standards or a chemical analogue as internal standards with an analytical range from 5.0 to 500.0 μg/L. The method performance characteristics that included overall recovery, intermediate precision, and measurement uncertainty were evaluated according to a nested experimental design. Generally, 98.4% (in red wine) and 96.8% (in white wine) of the pesticides had recoveries between 71 and 120%; 98.9% (in red wine) and 99.5% (in white wine) of the pesticides had the intermediate precision ≤20%; and 99.5% (in red wine) and 98.4% (in white wine) of the pesticides had measurement uncertainty ≤50%.

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