Simultaneous determination of sweeteners in beverages by LC-MS/MS.

A new method was established for the simultaneous determination of 10 sweeteners and a degradation product in beverages by using LC-MS/MS. An ACQUITY UPLC BEH C18 (2.1 × 100 mm, 1.7 µm) was used as the LC column and 0.1% each of aqueous formic acid and formic acid in acetonitrile were used as the mobile phase. A simple and rapid determination of sweeteners was possible by diluting with a solvent, and in the case of some samples containing a large amount of foreign matter, after pre-treatment by diluting with solvent and clean-up of the sample using an Oasis HLB cartridge. All the validation results were satisfactory. As the regulations and standards for sweeteners vary from country to country, a field survey of 58 beverages marketed in Japan was performed using the present method. No issues concerning the labelling or food sanitation law were found in the tested samples.

[High-sensitivity analysis of purines in alcoholic beverages using hydrophilic interaction chromatography coupled with tandem mass spectrometry].

In this study, we established a high-sensitivity analytical method for purines in alcoholic beverages using hydrophilic interaction chromatography coupled with tandem mass spectrometry. The alcoholic beverages were hydrolyzed with perchloric acid (60%) and subjected to strong cation exchange solid-phase extraction (Bond Elut SCX). The four purine bases (hypoxanthine, adenine, xanthine, guanine) in the extracted solution were separated by hydrophilic interaction chromatography with TSKgel Amide-80 as a separation column, 10 mM ammonium formate (pH 2.0) as mobile phase A, and acetonitrile/100 mM ammonium formate (pH 2.0) (90/10) as mobile phase B. The detection of purine bases was performed by tandem mass spectrometry with ESI. The linearity of this analytical method was not less than 0.996, and the repeatability was not more than 8.4% for each purine base. The recovery was in the range of 60-105%, and the detection limit was not more than 0.005 mg/100 mL. This established method is expected to be useful for quality control and surveillance of purines in alcoholic beverages.

[Simultaneous trichothecenes analysis by LC-MS/MS with a pentafluorophenyl column].

We developed a method for simultaneous analysis of nine trichothecenes (nivalenol, deoxynivalenol, fusarenon-X, neosolaniol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, diacetoxyscirpenol, HT-2 toxin, and T-2 toxin). Trichothecenes in samples were extracted with acetonitrile-water (1 : 1) and purified using a QuEChERS kit and a multi-functional cartridge. Then they were quantified by LC-MS/MS using internal standards. LC with a pentafluorophenyl column and a mobile phase containing methanol enabled complete separation and highly sensitive quantification of the nine trichothecenes. Method validation with powdered corn soup samples demonstrated high linearity (>0.99) and accuracy ranging from 95% to 111% with good repeatability of 0.9% to 6.6% and reproducibility of 0.6% to 11.6%. The limits of detection and quantification were 0.01 to 0.75 µg/kg and 0.04 to 2.50 µg/kg, respectively. When 15 samples from powdered corn soups on the market were analyzed with this method, deoxynivalenol was detected in two samples (20.7 and 22.5 µg/kg, respectively), and 3-acetyldeoxynivalenol was concomitantly detected in one of them (13.5 µg/kg).

[Structure identification of contaminants in a beverage product by liquid chromatography coupled with quadrupole time-of-flight mass spectrometry].

The contaminants in a beverage product that had been reported to have a strange taste were identified. By comparative analysis with the normal product using liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-QTOF-MS), six unknown compounds were detected in the total ion current chromatograms of the product in question. Detailed analysis of the mass spectra and product ion spectra of these compounds strongly suggested that the compounds were capric acid diethanolamide, lauric acid diethanolamide, myristic acid diethanolamide, lauryl dimethylaminoacetic acid, lauryl sulfate, and lauric acid, all of which are surfactants commonly used as ingredients of household detergents and shampoos. We searched commercially available detergent products to check for the presence of these six surfactants, and identified products that might have been intentionally or unintentionally mixed into the beverage product after opening.

Simultaneous LC-MS/MS analysis of glyphosate, glufosinate, and their metabolic products in beer, barley tea, and their ingredients.

Glyphosate and glufosinate are non-selective herbicides that have been extensively used worldwide. Their ionic and water-soluble characteristics often make it difficult to analyze them, especially in food components. A method was developed in this study for the simultaneous analysis of glyphosate, glufosinate, and three metabolic products in beer, barley tea, and their ingredients (malt and corn). The analytical samples were extracted with H2O, purified with a strong anion-exchange solid-phase extraction (SPE) cartridge, and then analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) with an anion-exchange high-performance liquid chromatography (HPLC) column. This method enabled a rapid and sensitive analysis [limit of quantification (LOQ) = 10 µg/kg] of the herbicides to be achieved.

Fate of mycotoxins during beer brewing and fermentation.

Mycotoxins are frequent contaminants of grains, and breweries need, therefore, to pay close attention to the risk of contamination in beer made from such grains as barley and corn. The fate of 14 types of mycotoxin (aflatoxins, fumonisins, ochratoxin A, patulin, trichothecenes, and zearalenone) during beer brewing was investigated in this study. Malt artificially spiked with each mycotoxin was put through the mashing, filtration, boiling and fermentation processes involved in brewing. After brewing, the levels of aflatoxins, ochratoxin A, patulin, and zearalenone were found to have decreased to less than 20% of their initial concentration. They had been adsorbed mainly to the spent grain and removed from the unhopped wort. Additionally, as zearalenone was known, patulin was metabolized to the less toxic compound during the fermentation process. The risk of carry-over to beer was therefore reduced for half of the mycotoxins studied. However, attention still needs to be paid to the risk of trichothecene contamination.

Degradation of aflatoxin B1 during the fermentation of alcoholic beverages.

Aflatoxin B1 (AFB1) is a contaminant of grain and fruit and has one of the highest levels of carcinogenicity of any natural toxin. AFB1 and the fungi that produce it can also contaminate the raw materials used for beer and wine manufacture, such as corn and grapes. Therefore, brewers must ensure strict monitoring to reduce the risk of contamination. In this study, the fate of AFB1 during the fermentation process was investigated using laboratory-scale bottom and top beer fermentation and wine fermentation. During fermentation, cool wort beer samples and wine must samples were artificially spiked with AFB1 and the levels of AFB1 remaining after fermentation were analyzed. AFB1 levels were unchanged during both types of fermentation used for beer but were reduced to 30% of their initial concentration in wine. Differential analysis of the spiked and unspiked wine samples showed that the degradation compound was AFB2a, a hydrated derivative of AFB1. Thus, the results showed that the risk of AFB1 carryover was still present for both types of beer fermentation but was reduced in the case of wine fermentation because of hydration.

A method for multiple mycotoxin analysis in wines by solid phase extraction and multifunctional cartridge purification, and ultra-high-performance liquid chromatography coupled to tandem mass spectrometry.

An analytical method using two solid phase extractions and ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed for the identification and quantification of 14 mycotoxins (patulin, deoxynivalenol, aflatoxins B(1), B(2), G(1), G(2), M(1), T-2 toxin, HT-2 toxin, zearalenone, fumonisins B(1), B(2), B(3), and ochratoxin A) in domestic and imported wines. Mycotoxins were purified with an Oasis HLB cartridge, followed by a MultiSep(TM) #229 Ochra. As a result, sufficient removal of the pigments and highly polar matrices from the red wines was achieved. UHPLC conditions were optimized, and 14 mycotoxins were separated in a total of 13 min. Determinations performed using this method produced high correlation coefficients for the 14 mycotoxins (R > 0.990) and recovery rates ranging from 76 to 105% with good repeatability (relative standard deviation RSD < 12%). Twenty-seven samples of domestic and imported wines were analyzed using this method. Although ochratoxin A (OTA) and fumonisins (FMs) were detected in several samples, the FM levels were less than limits of quantification (LOQs) (1 µg/L), and even the largest of the OTA levels was below the EU regulatory level (2 µg/L). These results suggest that the health risk posed to consumers from the wines available in Japan is relatively low.

The fate of mycotoxins during the distillation process of barley shochu, a distilled alcoholic beverage.

Mycotoxins are frequent contaminants of grains and critical risk substances for brewers. Fermented barley mash contaminated artificially with 13 representative mycotoxins was distilled with small-scale apparatuses to elucidate the possibility of mycotoxin transfer from mash to distillates. None of these were detected in the distillates. The distillation process can effectively reduce the contamination risk posed by mycotoxins in distilled alcoholic beverages.

Development of a multi-mycotoxin analysis in beer-based drinks by a modified QuEChERS method and ultra-high-performance liquid chromatography coupled with tandem mass spectrometry.

An analytical method was developed for the identification and quantification of 15 mycotoxins (patulin, nivalenol, deoxynivalenol, aflatoxin B(1), B(2), G(1), G(2), M(1), T-2 toxin, HT-2 toxin, zearalenone, fumonisin B(1), B(2), B(3), and ochratoxin A) in beer-based drinks (beer, low-malt beer, new genre, and nonalcoholic) by a modified QuEChERS method and an ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC/MS/MS). Mycotoxins were extracted from samples using acetonitrile with sodium chloride, anhydrous magnesium sulfate, and sodium citrate, and were then purified with a solid phase extraction (SPE) cartridge including C18. The UHPLC conditions were also examined to establish its optimal conditions for separation. Fifteen mycotoxins were separated in a total of 6.5 min, and were quantified in the optimal mobile phase conditions. Determinations performed using this method produced high correlation coefficients of 15 mycotoxins (R>0.99) and recovery rates ranging from 70.3 to 110.7% with good repeatability (relative standard deviation RSD<14.6%). Further, 24 commercial beer-based drinks in Japan were analyzed using this method, and nivalenol, deoxynivalenol, and fumonisins were detected in several samples, but always under the limit of quantification (<5 ng/mL). These results suggest that the health risk to consumers from beer-based drinks in Japan is relatively low.

Fate of pesticides during beer brewing.

The fates of more than 300 pesticide residues were investigated in the course of beer brewing. Ground malt artificially contaminated with pesticides was brewed via steps such as mashing, boiling, and fermentation. Analytical samples were taken from wort, spent grain, and beer produced at certain key points in the brewing process. The samples were extracted and purified with the QuEChERS (Quick Easy Cheap Effective Rugged and Safe) method and were then analyzed by LC-MS/MS using a multiresidue method. In the results, a majority of pesticides showed a reduction in the unhopped wort and were adsorbed onto the spent grain after mashing. In addition, some pesticides diminished during the boiling and fermentation. This suggests that the reduction was caused mainly by adsorption, pyrolysis, and hydrolysis. After the entire process of brewing, the risks of contaminating beer with pesticides were reduced remarkably, and only a few pesticides remained without being removed or resolved.

Fate of pesticides in a distilled spirit of barley shochu during the distillation process.

Moromi (the fermented mash) of "mugi shochu" that had been artificially contaminated with pesticides was distilled to elucidate the fate of pesticides in the distillation process. The pesticides residing in the distillate were quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Of the analyzed pesticides (249 compounds), 89% were not detected in the distillate, showing that the distillation process minimized the risk of pesticide contamination.

Determination of ochratoxin a in ready-to-drink coffee by immunoaffinity cleanup and liquid chromatography-tandem mass spectrometry.

We developed a simple and accurate method for determining ochratoxin A (OTA) in ready-to-drink coffee, using an immunoaffinity column for cleanup and liquid chromatography-tandem mass spectrometry (LC/MS/MS) for identification and quantification. When uniformly stable isotope-labeled OTA (U-[(13)C(20)]-OTA) was employed as an internal standard, the recovery rate of the method was 97.3% (the spiked OTA level was 0.10 ng/mL), the repeatability (relative standard deviation) was 1.9%, and the intermediate precision (relative standard deviation) was 4.0%. The limit of quantification was 0.0065 ng/mL based on a signal-to-noise ratio in coffee of 10:1. The developed method was used for the determination of OTA in ready-to-drink coffee. A total of 30 ready-to-drink coffee samples commercially available in Japan were analyzed. OTA was detected in all of the samples at concentrations ranging from trace levels (0.0020-0.010 ng/mL) to 0.037 ng/mL. This method was shown to be useful for accurately evaluating the intake of OTA from coffee beverages.