Pesticides' use in apiculture has a positive impact as it controls the population of pests and harmful insects, such as greater wax moth Galleria mellonella L., and ensures stable production for the hive products (Kast, Kilchenmann, & Charrière, 2021; Perez-Cobo, Fernández-Alba, & Hernando, 2022). Particularly the use of acaricides for control of the Varroa mite population is extensive (Bommuraj et al., 2019; Korta et al., 2001). In several studies, agropesticides are detected in hive matrices (Chiesa et al., 2016; Piechowicz, Mróz, Szpyrka, Zwolak, & Grodzicki, 2018) and beekeeping-associated pesticides persist in recycled bee wax for many years (Kast et al., 2021). Considering the cumulative nature of the residues, it becomes obvious that chronic consumption of these products is dangerous to consumers' health since they affect the nervous and reproductive systems (El-Nahhal, 2020; Giordano et al., 2007). Maximum residue limits (MRLs) have been regulated for some acaricide compounds, such as coumaphos, by the European Union (European Commission, 2005; European Parliament and the Council of the European Union, 2010) and the national legislation of many countries (Blasco et al., 2003). For several compounds, such as malathion, without legislated MRLs, detection limits are set as MRLs, and their mere detection leads to legal consequences. The problem with pesticides is more wide-spread in countries outside European Union, where several reports confirm their presence above the legislated MRLs (Eissa, El-sawi, & Zidan, 2014; Kumar, Gill, Bedi, & Kumar, 2018; Rafique et al., 2018; Yavuz, Guler, Aktumsek, Cakmak, & Ozparlak, 2010; Yu et al., 2015).

Several treatments, such as ultraviolet radiation, ultrasound (Yuan et al., 2022), heating, pasteurization (Abd-Rabo, Elsalamony, & Sakr, 2016), ozone treatment (Wang, Wang, Li, Xu, & Wu, 2021), addition of natural extracts, and washing (Venkatachalapathy et al., 2020; Wang et al., 2021), have been studied for residue reduction in foodstuffs. Household practices, such as cooking and boiling, have also been studied (Ishfaq, Sameen, Pasha, Shahid, & Abrar, 2022; Muralikrishna et al., 2016). However, several of these treatments cannot be applied to liquid foods, such as honey, and sometimes adversely affect the product quality (Claeys et al., 2013; Macdonald et al., 2011). Particularly, heating and pasteurization are treatments used in honey production, to tackle the natural phenomenon of crystallization (Molino et al., 2011; Yadav & Sircar, 2019) and to eliminate microorganisms (Escriche, Visquert, Carot, Domenech, & Fito, 2008). Both have been studied for their effect on pesticide residues (Tsigouri, Menkissoglu-Spiroudi, & Thrasyvoulou, 2001; Xu et al., 2012; Zhu et al., 2010) and their negative effect on honey quality (Escriche et al., 2008; Tosi, Martinet, Ortega, Lucero, & Ré, 2008). Filtration (Waliszewski, Infanzón, Carvajal, & Hart, 2003), photodegradation (Z. Yuan, Yao, Liu, Han, & Trebše, 2014), storage effect (Tsigouri et al., 2001), and adsorption resins (Xu et al., 2012) have also been studied as possible pesticide residue reduction methods in honey. However, the effectiveness of most of these treatments is limited. Information on the pesticides' persistence during processing will be useful for the development of an effective food safety program for honey.

Furthermore, there is a growing demand for the industry to manufacture minimally processed products that retain their nutritional quality and are safe from microbiological and chemical hazards (Gavahian, Pallares, Al Khawli, Ferrer, & Barba, 2020; Ranjitha Gracy, Sharanyakanth, & Radhakrishnan, 2022). High Hydrostatic Pressure (HHP) can serve this purpose, and is being increasingly used in the food industry to eliminate microbial hazards by rupturing microorganisms' cell wall, while preserving the product's sensory profile (Barba et al., 2015; Patterson, Linton, & Doona, 2008). A previous study proved that HHP reduced the concentration of antibiotic residues in various food matrices, including honey (Sidirokastritis, Tsiantoulas, Tananaki, & Vareltzis, 2022).

The effect of HHP on pesticide residues has been reported only in four studies involving cherry tomatoes (Iizuka, Maeda, & Shimizu, 2013; Iizuka & Shimizu, 2014b; Iizuka, Yahata, & Shimizu, 2013) and Brussels sprouts (Iizuka & Shimizu, 2014a). In these studies, whole vegetables were treated with HHP in water or alcoholic solution, and the leaching of the pesticides from the vegetables to the surrounding water was reported. To the best of our knowledge, the effect of HHP on pesticide residues has not yet been studied in liquid foods. These foodstuffs, such as honey, are packaged before treatment and therefore the leaching of residues from the food matrix into the surrounding liquid medium is not possible. However, HHP processing has been reported that has a mild effect on honey quality (Al-Habsi & Niranjan, 2012; Önür et al., 2018), while several studies claim that it enhances its antioxidant profile (Akhmazillah, Farid, & Silva, 2013; Akhmazillah Fauzi & Mehdi Farid, 2017; Chaikham & Prangthip, 2015; Fauzi, Farid, & Silva, 2014; Leyva-Daniel, Escobedo-Avellaneda, Villalobos-Castillejos, Alamilla-Beltrán, & Welti-Chanes, 2017).

The scope of this study is to investigate the effect of High Hydrostatic Pressure (HHP) on the residues of four acaricides and one agropesticide in honey, as well as to explore processing parameters for maximum residue decrease. The selected acaricides include coumaphos, tau-fluvalinate, bromopropylate, and malathion. These compounds have been widely used in apiculture for decades, and their residues are still present in beehive products such as wax (Kast et al., 2021; Murcia-Morales, Heinzen, Parrilla-Vázquez, del Gómez-Ramos, & Fernández-Alba, 2022; Perez-Cobo et al., 2022). The agropesticide chlorpyrifos was chosen, as it is often reported in beehive products such as honey (Saitta et al., 2017; Tong et al., 2018). A full factorial experimental analysis of the pressure, temperature and processing time was conducted to investigate the effect of these factors on HHP efficiency. The effect of O2 presence in the packaging was also studied by applying different vacuum levels. Finally, the physicochemical properties of the treated honey were determined to evaluate the quality of the treated samples.