Distribution pattern, removal effect, transfer behavior of ten pesticides and one metabolite during the processing of grapes

Residue changes, degradation, processing factors and their relation between physicochemical properties of pesticides in peanuts during multiproduct processing

This study systematically investigates the residue changes, processing factors (PFs), and relation between the physicochemical properties of pesticides during peanut processing. Results revealed that peeling, washing, and boiling treatments removed partial or substantial pesticide residues from peanuts with PFs of 0.29-1.10 (most <1). By contrast, pesticides appeared to be partially concentrated during roasting, stir-frying, and deep-frying peanuts with PFs of 0.16-1.25. During oil pressing, 13 of the 28 pesticides were concentrated in the peanut oil (PF range: 1.06-2.01) and 25 of the pesticides were concentrated in the peanut meal (1.07-1.46). Physicochemical parameters such as octanol-water partition coefficient, degradation point, molecular weight, and melting point showed significant correlations with PFs during processing. Notably, log Kow exhibited strong positive correlations with the PFs of boiling, roasting, and oil pressing. Overall, this study describes the fate of pesticides during multiproduct processing, providing guidance to promote the healthy consumption of peanuts for human health.

Occurrence, dissipation and processing factors of multi-pesticides in goji berry

As medicine and food homology substance, goji berry is consumed worldwide in the form of fresh, dried and juice; however, pesticide residues have become one of the problems that essentially threaten its quality during cultivation and processing. In this study, a total of 75 dried goji berries were sampled from markets across China, and for the determination of 62 analytes, 28 pesticides were identified. Nine pesticides with high detectable rates and residual levels were selected for folia spraying, and their half-lives were found to range from 1.04 to 2.21 d. The processing factors (PFs) of juice were between 0.25 and 1.02, and this was mainly related with their octanol-water partition coefficient (logKow values). Washing could reduce pesticides residues to varying degrees with the removal rates between 17.00% and 74.05%. Sun drying with higher PF values in the range of 0.61-5.91 exhibited more obvious enrichment effect compared to oven drying. Commercial goji berry had cumulative chronic dietary risks with the hazard index (HI) values of 1.61%-4.97%. Its acute risk quotients (HQas) for consumers were 543.32%-585.92% and were mainly due to insecticides. These results provide important references for rationalizing pesticide application during goji berry cultivation and for the improvement of process to ensure food safety.

Residue levels, processing factors and risk assessment of pesticides in ginger from market to table

Ginger is consumed as a spice and medicine globally. However, pesticide residues in ginger and their residue changes during processing remain poorly understood. Our results demonstrate that clothianidin, carbendazim and imidacloprid were the top detected pesticides in 152 ginger samples with detection rates of 17.11-27.63%, and these pesticides had higher average residues of 44.07-97.63 μg/kg. Although most samples contained low levels of pesticides, 66.45% of the samples were detected with pesticides, and 38.82% were contaminated with 2-5 pesticides. Peeling, washing, boiling and pickling removed different amounts of pesticides from ginger (processing factor range: 0.06-1.56, most <1). By contrast, pesticide residues were concentrated by stir-frying and drying (0.50-6.45, most >1). Pesticide residues were influenced by pesticide physico-chemical parameters involving molecular weight, melting point, degradation point and octanol-water partition coefficient by different ginger processing methods. Chronic and acute dietary risk assessments suggest that dietary exposure to pesticides from ginger consumption was within acceptable levels for the general population. This study sheds light on pesticide residues in ginger from market to processing and is of theoretical and practical value for ensuring ginger quality and safety.

Residue behaviors of six pesticides during apple juice production and storage

The residue behaviors of carbendazim, thiamethoxam, imidacloprid, acetamiprid, prochloraz, and difenoconazole during the production and accelerated storage of apple clear and cloudy juice was systemically evaluated. The pesticides were determined by liquid chromatography-mass spectrometry (LC-MS/MS) after each processing step and at different storage times. The results indicated that the different processing steps in the apple clear and cloudy juices production have different effects on the reduction of pesticide residues. The pre-processing steps including washing and pressing reduced the pesticide residues significantly by 36.8 % to 67.9 % and 32.9 % to 89.8 %, respectively, mainly due to the water solubility and log Kow of pesticides. The enzymation step in clear juice production slightly reduced six pesticide residues from 1.9 % to 31.6 %, and the filtration step after clarification and purification decreased the pesticide residues from 14.0 % to 87.5 % with no significance, while prochloraz was not detected. The centrifugation step in cloudy juice production reduced the pesticide residues from 6.3 % to 88.9 %. The pasteurization step in clear and cloudy juice production lowered the pesticide residues slightly on account of the short heating time of 30 s. The accelerated storage of clear and cloudy juices was effective in the reduction of pesticide residue levels. The processing factors (PFs) in the whole process of clear and cloudy juice production were equal to or lower than 0.2, especially for prochloraz and difenoconazole, illustrating that apple juice production could decrease the pesticide residues greatly. The results will provide important references to predict the levels of pesticide residues in apple juice during processing and storage. Meanwhile, the PFs identified in the study could be helpful in the risk assessment of pesticides in apple juice.

The interaction effects of pesticides with Saccharomyces cerevisiae and their fate during wine-making process

Pesticide residues in grapes could be transferred to fermentation system during the wine-making process, which may interfere the normal proliferation of Saccharomyces cerevisiae and subsequently affect the safety and quality of wine products. However, the interaction between pesticides and Saccharomyces cerevisiae is still poorly understood. Herein, the fate, distribution and interaction effect with Saccharomyces cerevisiae of five commonly-used pesticides during the wine-making process were evaluated. The five pesticides exerted varied inhibition on the proliferation of Saccharomyces cerevisiae, and the order of inhibition intensity was difenoconazole > tebuconazole > pyraclostrobin > azoxystrobin > thiamethoxam. Compared with the other three pesticides, triazole fungicides difenoconazole and tebuconazole showed stronger inhibition and played a major role in binary exposure. The mode of action, lipophilicity and exposure concentration were important factors in the inhibition of pesticides. Saccharomyces cerevisiae had no obvious impacts on the degradation of target pesticides in the simulated fermentation experiment. However, the levels of target pesticides and their metabolite were significantly reduced during the wine-making process, with the processing factors ranged from 0.030 to 0.236 (or 0.032 to 0.257) during spontaneous (or inoculated) wine-making process. As a result, these pesticides were significantly enriched in the pomace and lees, and showed a positive correlation (R² ≥ 0.536, n = 12, P < 0.05) between the hydrophobicity of pesticides and distribution coefficients in the solid-liquid distribution system. The findings provide important information for rational selection of pesticides on wine grapes and facilitate more accurate risk assessments of pesticides for grape processing products.

Detection methods, migration patterns, and health effects of pesticide residues in tea

Due to its rich health benefits and unique cultural charm, tea drinking is increasingly popular with the public in modern society. The safety of tea is the top priority that affects the development of tea industry and the health of consumers. During the process of tea growth, pesticides are used to prevent the invasion of pests and diseases with maintaining high quality and stable yield. Because hot water brewing is the traditional way of tea consumption, water is the main carrier for pesticide residues in tea into human body accompanied by potential risks. In this review, pesticides used in tea gardens are divided into two categories according to their solubility, among which water-soluble pesticides pose a greater risk. We summarized the methods of the sample pretreatment and detection of pesticide residues and expounded the migration patterns and influencing factors of tea throughout the process of growth, processing, storage, and consumption. Moreover, the toxicity and safety of pesticide residues and diseases caused by human intake were analyzed. The risk assessment and traceability of pesticide residues in tea were carried out, and potential eco-friendly improvement strategies were proposed. The review is expected to provide a valuable reference for reducing risks of pesticide residues in tea and ensuring the safety of tea consumption.