RESUMEN
Fruits, vegetables, and shellfish are often associated with outbreaks of illness caused particularly by human norovirus (HuNoV) and hepatitis A virus (HAV), the leading causative agents of foodborne illness worldwide. The aim of this study was to evaluate a new automated nucleic acid extraction platform (EGENE-UP EASYPREP) for enteric viruses in several at-risk food matrices and to test its limit of detection in comparison to a semi-automated method (EGENE-UP) using Boom methodology for nucleic acid extraction as suggested in the reference method ISO 15216-2:2019. Fresh and frozen raspberries, frozen blackberries, romaine lettuce and oyster digestive glands were artificially contaminated with HAV, HuNoV GII.4 or HuNoV GI.7 at 102, 103 or 104 genome copies/sample. Virus was then recovered from the food matrix using the ISO method. Viral RNA extracted from frozen berry samples by the automated system was purified on a column for additional removal of RT-qPCR inhibitors. For fresh raspberry, oysters, and romaine lettuce, the two extraction platforms were deemed equivalent. For frozen raspberry, the automated platform appeared to be more efficient for viral recovery, particularly for HAV and HuNoV GI at lower concentrations. With frozen blackberries, the two platforms may be considered equivalent for all targeted viruses. However, the automated method led to less sample-associated inhibition of the PCR, 56.5 % of samples versus 95.0 % for the semi-automated. We thus found that the automated extraction can be performed easily by users while obtaining equivalent or even superior results to the ISO 15216-2:2019 method, and therefore appears to be suitable for routine sanitary monitoring in food processing and for tracing outbreaks of illness.
Asunto(s)
Virus de la Hepatitis A , Norovirus , Ostreidae , Virus , Animales , Humanos , Virus de la Hepatitis A/genética , Norovirus/genética , Frutas/química , Lactuca , ARN Viral/análisis , Contaminación de Alimentos/análisisRESUMEN
Pesticide residues on foods are a global concern due to the impact on human health. Many countries have adopted regulations to establish Maximum Residue Levels (MRLs) to control use of pesticides. This study aimed to determine pesticide residues in frozen fruit and vegetables from Chilean retail stores using UHPLC-Orbitrap MS and QuEChERS™ multiresidue-extraction kit. 237 samples of frozen produce were sampled from different supermarkets and times during the year. Abamectin, Chlorpyrifos, Imidacloprid, Iprodione, λ-cyhalothrin, Spinosad A, and Spinosad D were quantified. Results showed that Iprodione, Spinosad A, and D were the most detected molecules. Pesticides were detected in 96.6% of samples and 21 samples exceeded MRL. Corn and faba beans showed the highest concentration of Iprodione with an average of 6.7 and 5.4â¯mg/Kg, respectively. Existence of nonconformity in samples highlights the importance to control pesticide residues of Chilean frozen produce, since it represents a latent health threat on consumers.
Asunto(s)
Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Frutas/química , Residuos de Plaguicidas/análisis , Verduras/química , Fraccionamiento Químico , Chile , Cromatografía Líquida de Alta Presión/métodos , Almacenamiento de Alimentos/métodos , Congelación , Humanos , Espectrometría de Masa por Ionización de Electrospray/métodosRESUMEN
Despite convenience and nutrition advantages of frozen vegetables, consumption of them is low compared with fresh vegetables and continues to decrease. In two studies, we observe a negative bias for frozen vegetables compared with fresh vegetables. In study 1, we used an Implicit Association Test (IAT) to demonstrate that generalized negative associations with frozen vegetables are automatic, robust, and ingrained in long-term memory. In study 2, we conceptually replicate this finding with an explicit measure and extend it by examining the role of transforming the food product in formation of the observed negative bias. We find no improvement in evaluation for frozen spinach when participants contemplate the final cooked product. Instead, we see less favorable evaluations of fresh spinach when participants contemplate the final cooked product. These findings are consistent with previous research that demonstrates that transformation of a food from its "natural" state leads to less favorable evaluations of it.