Effect of pesticide residues on simulated beer brewing and its inhibition elimination by pesticide-degrading enzyme

Understanding How Chemical Pollutants Arise and Evolve in the Brewing Supply Chain: A Scoping Review

In this study, a critical review was carried out using the Web of ScienceTM Core Collection database to analyse the scientific literature published to date to identify lines of research and future perspectives on the presence of chemical pollutants in beer brewing. Beer is one of the world's most popular drinks and the most consumed alcoholic beverage. However, a widespread challenge with potential implications for human and animal health is the presence of physical, chemical, and/or microbiological contaminants in beer. Biogenic amines, heavy metals, mycotoxins, nitrosamines, pesticides, acrylamide, phthalates, bisphenols, microplastics, and, to a lesser extent, hydrocarbons (aliphatic chlorinated and polycyclic aromatic), carbonyls, furan-derivatives, polychlorinated biphenyls, and trihalomethanes are the main chemical pollutants found during the beer brewing process. Pollution sources include raw materials, technological process steps, the brewery environment, and packaging materials. Different chemical pollutants have been found during the beer brewing process, from barley to beer. Brewing steps such as steeping, kilning, mashing, boiling, fermentation, and clarification are critical in reducing the levels of many of these pollutants. As a result, their residual levels are usually below the maximum levels allowed by international regulations. Therefore, this work was aimed at assessing how chemical pollutants appear and evolve in the brewing process, according to research developed in the last few decades.

Fate of pesticide residues in beer and its by-products

Sustainable beer production requires a comprehensive assessment of potential hazards such as pesticides in both the finished product and waste streams, as these streams can be used to create high-value by-products. This study presents the tracking of 13 fungicides (azoxystrobin, boscalid, epoxiconazole, fenpropidin, fenpropimorph, fluquiconazole, flutriafol, fluxapyroxad, kresoxym-methyl, spiroxamine, propiconazole, prothioconazole-desthio, and tebuconazole), two insecticides (chlorpyrifos-methyl and deltamethrin), one herbicide (glyphosate), and one growth regulator (mepiquat) through the beer brewing process. Field-treated rye, wheat, and barley samples containing pesticide residues were used as adjunct during brewing. Samples of the beer as well as the by-products (spent grain, spent hops, trub and spent yeast) were collected and extracted with a modified QuEChERS method for pesticide residues analysis using GC-MS/MS and LC-MS/MS. Results show that an average of 58% of pesticide residues are retrieved in the by-products with the highest fraction (53%) recovered in the spent grain, 4% in trub, 1% in spent hops, no residues detected in spent yeast and 9% in the beer. This is consistent with these nonpolar pesticides tending to remain adsorbed to the spent grain during brewing. Glyphosate and mepiquat, the most polar pesticides included in this study, showed a different behavior, with the largest fraction (>80%) being retrieved in sweet wort and transferred to the beer. Processing factors were generated for each pesticide from the adjunct to the beer and to the four by-products.

Comprehensive Review on Monitoring, Behavior, and Impact of Pesticide Residues during Beer-Making

This paper reviews the impact of beer-making stages (malting, mashing, boiling, and fermentation) on the behavior of pesticide residues. The large use of pesticides on barley and hop could cause the occurrence of their residues in beer. The foremost factors influencing the stability of residues (pH, temperature, and water content) and the physical-chemical properties of pesticides (octanol-water partition coefficient, vapor pressure, and water solubility) are essential to know their final fate. Most pesticides show a decrease in the unhopped wort because they are adsorbed onto the spent grains after mashing. In addition, their concentrations decrease during boiling and fermentation. Generally, maltsters should dedicate particular attention to the residues of hydrophobic pesticides because they can remain on the malt. Contrarily, brewers should control residues of hydrophilic pesticides because they can be carried over into young beer, disturbing the quality and organoleptic properties (flavor, aroma, taste, or color) of the beer.

Residues of pesticides and veterinary drugs in diets of dairy cattle from conventional and organic farms in Austria

Modern agriculture depends highly on pesticides and pharmaceutical preparations, so controlling exposure to these substances in the feed and food chain is essential. This article presents the first study on residues of a broad spectrum of pesticides and veterinary drugs in the diets of dairy cattle. One hundred and two representative samples of the complete diets, including basal feed rations and additional fed concentrate, were collected in three Austrian provinces (Styria, Lower and Upper Austria) in 2019 and 2020. The samples were tested for >700 pesticides, veterinary drugs and related metabolites using a validated method based on liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS). In total, 16 residues (13 pesticides and three veterinary drug residues) were detected. > 90% of the diets contained pesticide residues and <10% veterinary drug residues, whereas banned pesticides were not found. The most frequent pesticide residues were fluopyram (62%), piperonyl butoxide (39%) and diethyltoluamide (35%). The following pesticides exceed the default EU maximum residue level (MRL) (10 μg kg^-1) for products exclusively used for animal feed production: Benzovindiflupyr (proportion of samples > MRLs: 1%), bixafen (2%), fluopyram (6%), ipconazole (1%) and tebuconazole (3%). Three residues (dinitrocarbanilide, monensin and nicarbazin) of veterinary drugs were identified, all below the MRLs. Over 60% of the evaluated samples contained mixtures of two to six residues/sample. Only one pesticide (diethyltoluamide) presented a significant difference among regions, with higher concentrations in Upper Austria. Brewery's spent grains were the dietary ingredient that showed the strongest correlation to pesticide residues. These findings evidence the realistic scenario of highly occurrent low doses of pesticides cocktails in the feed/food chain, which may affect the animal, human and environmental health. Since the risk assessments are based on single pesticides, the potential synergistic effect of co-occurring chemicals ("cocktail effect") requires further investigations.

Comparative analysis of mycotoxin, pesticide, and elemental content of Canarian craft and Spanish mainstream beers

The number of craft breweries and the volume of craft beer produced globally is growing exponentially. However, little is known about their differences with mainstream beers regarding mycotoxin profile, pesticide and pollutant residues and elemental composition. Given that beer is one of the most consumed beverages worldwide, it is important to shed light on its toxicological profile. In this study, samples of 23 craft beers and 19 mainstream Spanish beers were collected to perform a comparative analysis including 8 mycotoxins, 225 pesticide residues and 50 POPs, and 50 elements. Mycotoxins were not detected in craft beers, while 100% of mainstream beers presented at least one mycotoxin. In contrast, craft beers contained higher average pesticide residues than their mainstream counterparts, although significant differences were only found in Mepiquat and Metrafenone content. No persistent organic pollutants were detected in any sample. The elemental composition presented differences between the two groups both in the concentration of elements and their hierarchy. In conclusion, the toxicological profile of all beers was safe and is unlikely to constitute a hazard to consumer health. Craft beers present significant differences from their mainstream counterparts in all the dimensions explored.

Robotic written silver ink on photographic paper for detection of thiram residues in fruits

With the widespread application of pesticide in agriculture, pesticide residues in food have posed serious health risks to human. There is an urgent requirement to detect pesticide residues in food. In this work, a sensitive and effective method was employed to measure thiram residues in fruit using surface-enhanced Raman scattering (SERS) technique. Silver ink was written on photographic paper (AgNPs-photographic paper) directly by robotic writing technique. The AgNPs-photographic paper substrates possessed good SERS activities and high stability among four months. A good linear response between the peaks intensities and the logarithmic concentrations of thiram was obtained with the limit of detection (LOD) of 0.024 ppb. The substrates also exhibited excellent reproducibility with relative standard deviation (RSD) value less than 10% from ten different substrates. SERS mapping was tested to characterize the uniformity of AgNPs-photographic paper, and the RSD value was calculated to be 14.34% at 1377 cm^-1 measured by 120 points. The LOD values of apple and peach juice adulterated with thiram were 0.0024 and 0.024 ppm, respectively. The LOD values of thiram residues on apple and peach peels were both 0.25 ng/cm². It was demonstrated that the substrates prepared by robotic writing technique had great potential for practical application in food safety inspection.

Expression, characterization, and immobilization of a novel SGNH esterase Est882 and its potential for pyrethroid degradation

The widely-used pyrethroid pesticides have attracted public attention because of their potentials to cause environmental pollution and toxic effects on non-target organisms. Esterase is a kind of hydrolytic enzyme that can catalyze the cleavage or formation of ester bonds. it plays a pivotal role in the decomposition of pyrethroids and esters containing industrial pollutants through the hydrolysis of ester bonds. Here, a new esterase gene est882 was successfully screened, which encodes Est882, a SGNH family esterase composed of 294 amino acids. It was heterogeneously expressed, identified and immobilized. Multiple sequence alignment showed that Est882 had a typical GDS(X) conserved motif and a catalytic triad composed of Ser79, Asp269 and His275. Phylogenetic analysis showed that Est882 shall belong to a new esterase family. Biochemical characterization demonstrated that the optimum condition was 40°C and pH 9.0. Est882 immobilization was studied with mesoporous silica SBA-15 as the carrier and found to significantly improve the tolerance and stability of Est882. Its optimum pH increased to 10.0 and stabilized within pH 8.0-11.0. Free Est882 can effectively degrade various pyrethroids within 30 min, with a degradation rate above 80%. The immobilized Est882 yet degraded more than 70% of pyrethroids within 30 min. The present study indicated that Est882 has outstanding potential in bioremediation of a pyrethroid-polluted environment. These characteristics endow Est882 with potential values in various industrial applications and hydrolysis of pyrethroid residues.