**1. Introduction**

Orange (*Citrus sinensis*) is one of the most popular and most-grown citrus families in the world. According to the Turkish Mediterranean Exporters' Association, the citrus group took first place in Turkish total fruit and vegetable exports between 2017 and 2018 (405.2 million tons) [1]. Valencia is the most important orange variety grown in Turkey, and its farming has been increasing rapidly in recent years. Its most important feature is that it can be grown and harvested up to the late months of the spring. The peel of the fruit is slightly rough and moderately thick and the inner skin is thick and contains few seeds. Orange is a good source of vitamins, flavonoids, terpenes, potassium, and calcium, and fulfills most of the daily need for vitamin C for consumers. Orange can be consumed fresh or processed domestically or industrially into jam, marmalade, or fruit juice, in addition to its frozen and dried forms [2]. Orange peel is used as a flavoring agent in the pastry sector and essential oils extracted from the peels are used in the cosmetics industry.

Since citrus fruits are cultivated in warm and subtropical climates where unwanted pests and wild herbs are common, it is normal agricultural practice to use pesticides to increase the yield of the crop [3]. However, excessive and unprescribed spraying and early harvesting can leave residues in the product, which may adversely affect the safety of the food consumed. Pesticide residue levels in foods must be safe for consumers, so national and international authorities have set maximum residue limits (MRL) for fresh fruits and vegetables, animal products, and feeds [4] (EC 2005). Processing factor (*P*F) is defined as

**Citation:** Omeroglu, P.Y.; Acoglu Celik, B.; Koc Alibasoglu, E. The Effect of Household Food Processing on Pesticide Residues in Oranges (*Citrus sinensis*). *Foods* **2022**, *11*, 3918. https://doi.org/10.3390/ foods11233918

Academic Editors: Roberto Romero-González, Dapeng Peng and Yongzhong Qian

Received: 6 October 2022 Accepted: 1 December 2022 Published: 5 December 2022

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the ratio of pesticide residue level in processed food to the pesticide residue level in the raw agricultural commodity (RAC). Processing factors are taken into account when verifying the compliance of residues in processed products with the MRL of agricultural commodities and to refine dietary exposure intake with respect to residues in processed products [5–7]. The studies reported in the literature revealed that pesticide residues in RACs can be decreased or increased as a result of the processes applied during the preparation of the products for consumption both at industrial and household-scale productions, including washing, peeling, freezing, heating, and drying [8–11].

Although oranges and their products are widely consumed throughout the world, the fate of the pesticide residues during the processing of oranges has been revealed in a limited number of studies in the literature [2,3,12–14]. The panel of experts on Pesticide Residues in Food and the Environment and the WHO Core Assessment Group on Pesticide Residues reported processing factors for different type of pesticides in food commodities. The reports included processing factors of pasteurized or canned orange juice, canned orange marmalade, dried orange peel oil, dried orange pulp, and chopped fresh orange peel, for different type of pesticides including buprofezin, dimethoate fenpyroximate, fluensulfone, imizalil metalxyl, mandipropamid, omethate, and pydiflumetofen [14]. Since processing effects depend on the physicochemical properties of the pesticide in addition to the type of the process and the matrix, processing factors should be individually determined for each pesticide, process, and matrix combination [5,15]. Therefore, there is still a need for further studies on the other common pesticides and household processing of oranges. In the light of the needs in the literature, we aimed to study the effects of various household food processing techniques (washing with tap water, peeling, pulping, processing to jam or fruit juice, storage of frozen grated peels for a certain period of time) on the initial concentration of abamectin, buprofezin, etoxazole, imazalil, and thiophanate-methyl residues in oranges. The pesticides were selected among the authorized commercial pesticides commonly used for local farming applications of citrus in Turkey.
