Influence of infrared final cooking on polycyclic aromatic hydrocarbon formation in ohmically pre-cooked beef meatballs Perihan Kendirci a, ⁎, Filiz Icier a , Gamze Kor b , Tomris Altug Onogur a a Ege University, Engineering Faculty, Food Engineering Department, 35100 Bornova, Izmir, Turkey b Ege University, Institute of Natural and Applied Sciences, Food Engineering Program, 35100 Bornova, Izmir, Turkey abstract article info Article history: Received 26 November 2013 Received in revised form 27 January 2014 Accepted 30 January 2014 Available online 8 February 2014 Keywords: Infrared Cooking Meatball PAH Ohmic Effects of infrared cooking on polycyclic aromatic hydrocarbon (PAH) formation in ohmically pre-cooked beef meatballs were investigated. Samples were pre-cooked in a specially designed-continuous type ohmic cooking at a voltage gradient of 15.26 V/cm for 92 s. Infrared cooking was applied as a final cooking method at different combinations of heat fluxes (3.706, 5.678, 8.475 kW/m 2 ), application distances (10.5, 13.5, 16.5 cm) and applica- tion durations (4, 8, 12 min). PAHs were analyzed by using high performance liquid chromatography (HPLC) equipped with a fluorescence detector. The total PAH levels were detected to be between 4.47 and 64 μg/kg. Benzo[a] pyrene (B[a]P) and PAH4 (sum of B[a]P, chrysene (Chr), benzo[a]anthracene (B[a]A) and benzo[b]fluo- ranthene (B[b]F)) levels detected in meatballs were below the EC limits. Ohmic pre-cooking followed by infrared cooking may be regarded as a safe cooking procedure of meatballs from a PAH contamination point of view. © 2014 Elsevier Ltd. All rights reserved. 1. Introduction Polycyclic aromatic hydrocarbons (PAHs) are defined as chemically stable lipophilic compounds containing two or more fused aromatic rings made up of carbon and hydrogen atoms (Ciecierska & Obiedzinski, 2007; Djinovic, Popovic, & Jira, 2008; IPCS-INCHEM, 1995; Mottier, Parisod, & Turesky, 2000; Yildiz-Turp, Sengun, Kendirci, & Icier, 2013). They are also described as environmental contaminants formed as a re- sult of incomplete combustion or pyrolysis of coal, oil, fuel, garbage and other organic substances, as well as processing of crude oil and natural gases. Vehicle emissions and the tobacco smoke also contain PAHs (Chen, Wang, & Chiu, 1996; Chiu, Lin, & Chen, 1997; Ciecierska & Obiedzinski, 2007; IPCS-INCHEM, 1995). Foods can be contaminated with PAHs through environmental pollution, packaging materials or some food processing techniques such as drying, baking, grilling, roasting and smoking (IPCS-INCHEM, 1995; Mottier et al., 2000; Yildiz-Turp et al., 2013). Almost all cooking procedures cause PAH formation on meat and meat products at different levels. It is stated that smoking, grilling and roasting cause PAH formation in high levels, while mild cooking condi- tions such as steaming can reduce PAH formation levels (Yildiz-Turp et al., 2013). Ohmic heating is an electrical heating technique based on the passage of electrical current through a food product that has electrical resistance (Yildiz-Turp et al., 2013). It can be used for different purposes such as boiling, drying, fermentation, extraction, pasteurization, sterilization and enzymatic deactivations (Icier, Yildiz, & Baysal, 2005; Jun & Sastry, 2007; Leizerson & Shimoni, 2005a,b; Lima & Sastry, 1999; Mizrahi, 1996; Sastry & Barach, 2001; Sensoy & Sastry, 2004). The advantages of ohmic heating compared to the traditional heating systems can be sum- marized as shorter processing times, higher yields, maintenance of the color and nutritional value of foods (Icier et al., 2013; Yildiz-Turp et al., 2013). Ohmic cooking of meat and meat products by using ohmic heating procedure can cause PAH formation in meat and meat products. There are limited studies about PAH formation in ohmically cooked meat and meat products. It is reported in a study that, benzo[a]pyrene levels of ohmically pre-cooked beef meatballs using three different voltage gradients (17.5, 20.0 and 22.5 V/cm) were found to be 0.10, 0.09 and 0.09 ppb, respec- tively (Icier et al., 2012). PAH levels of ohmically cooked meatball samples by using optimum ohmic heating conditions, which were pre-determined as cooking up to 75 °C center temperature by applying 15.26 V/cm voltage gradient without holding time, were determined as 0.03 ppb (naphthalene (Naph)), 0.97 ppb (acenaphthene (Ace)), 1.44 ppb (fluorene (Fln)), 0.05 ppb (phenanthrene (Phe)), 0.29 ppb (pyrene (Pyr)), 0.33 ppb (anthracene (Ant)), 0.33 ppb (fluoranthene (Flt)), 0.19 ppb (benzo[b]fluoranthene (B[b]F)), 0.09 ppb (benzo[k] fluoranthene (B[k]F)), 0.09 ppb (benzo[a]pyrene (B[a]P)), 0.71 ppb (dibenzo[a,h]anthracene (DB[ah]A)) and 0.18 ppb (benzo[g,h,i]perylene (B[ghi]P)) while benzo[a]anthracene (B[a]A), chrysene (Chr) and indeno [1,2,3-cd]pyrene (I[cd]P) were not detected (Sengun, Yildiz-Turp, Icier, Kendirci, & Kor, 2014). Although ohmic cooking provides homogeneous cooking, it doesn't cause enough crust formation on the outer surface of meatballs which is necessary for visual acceptability. Infrared cooking can be combined with ohmic cooking in order to increase the sensory appearance quality Meat Science 97 (2014) 123–129 ⁎ Corresponding author. Tel.: +90 232 3113028; fax: +90 232 3427592. E-mail address: perihan.kendirci@ege.edu.tr (P. Kendirci). 0309-1740/$ – see front matter © 2014 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.meatsci.2014.01.020 Contents lists available at ScienceDirect Meat Science journal homepage: www.elsevier.com/locate/meatsci