Short communication Impact of the presence of oxytetracycline residues in milk destined for the elaboration of dairy products: The specific case of mature goat cheese P. Quintanilla a , M. Cornacchini b , M.I. Hernando c , M.P. Molina a , I. Escriche d, * a Institute for Animal Science and Technology, Universitat Polit ecnica de Val encia, Camino de Vera, s/n, 46022, Valencia, Spain b National Institute of Industrial Technology, San Martín, B1650WAB, Buenos Aires, Argentina c Food Microstructure and Chemistry Research Group, Department of Food Technology, Universitat Polit ecnica de Val encia, Camino de Vera, s/n, 46022, Valencia, Spain d Institute of Food Engineering for Development, Department of Food Technology, Universitat Polit ecnica de Val encia, Camino de Vera, s/n, 46022, Valencia, Spain article info Article history: Received 3 January 2019 Received in revised form 24 October 2019 Accepted 24 October 2019 Available online 6 November 2019 abstract This study evaluated instrumental parameters (chemical composition, colour, texture and microstruc- ture) and sensory characteristics of goat cheese (60-day maturation) made with milk spiked with oxytetracycline at different levels: 0, 50, 100 (maximum residue limit; MRL) and 200 mg kg À1 . Addi- tionally, the influence of this antibiotic on the cheese making process was evaluated and proved that the presence of oxytetracycline in milk significantly delayed the total time of manufacture in proportion to its concentration. The presence of this antibiotic in raw milk, even at a concentration of up to double the MRL, affected some of the parameters only slightly (pH, FFA concentration, luminosity, springiness and chewiness) in the ripened cheeses, without being perceptible by the sensory panel. Consequently, cheese made from milk containing oxytetracycline would go unnoticed by consumers. © 2019 Elsevier Ltd. All rights reserved. 1. Introduction Oxytetracycline is the most commonly used tetracycline for food-producing species in veterinary treatment of diseases (EMA, 2018). Improper use of antibiotics, especially with regard to the withdrawal period, could be a cause for the presence of antibiotic residues in milk and, therefore, in dairy products. To ensure food safety, maximum residue limits (MRLs) for different pharmaco- logically active substances in foods of animal origin, such as milk, have been established (European Commission, 2010); however, for some dairy products, no limits have been set for antibiotics. In industrialised countries, antibiotic control is routine in the dairy industry, provided that specific screening methods are used for tetracyclines, but their use is rather rare in goat milk (Beltr an, Althaus, Molina, Berruga, & Molina, 2015); thus, the presence of residues does not pose a great risk to the consumer in such coun- tries. However, most goat milk is produced in underdeveloped countries, where there are either no control systems in place or they are poorly implemented, making it more likely that milk containing antibiotic residues could be used in cheese-making. Indeed, antibiotic residues have been found in marketed dairy products such as cheese (Tona & Olusola, 2014). Recently, in an investigation of fresh goat cheese, made with milk containing a concentration equivalent to MRL, Quintanilla, Dom enech, Escriche, Beltr an, and Molina (2019b) found that oxytetracycline was retained to a large extent (37% rate of the initial concentration in milk). The presence of antibiotic residues in milk destined for the production of dairy products could have adverse effects on human health (Berruga, Molina, Althaus, & Molina, 2016) and also have negative technological effects (Berruga, Molina, Noves, Rom an, & Molina, 2007; Cabizza et al., 2017). Expanding the knowledge of the impact of the presence of antibiotics on the manufacturing process, and the physicochemical characteristics of dairy products is of great importance for the industry, the consumer and health administrations. Therefore, the present study focuses on mature cheese made from goat milk spiked at different levels (MRL and/or above and below) with oxytetracycline by evaluating its impact on * Corresponding author. Tel.: þ34 963877007x73661. E-mail address: iescrich@tal.upv.es (I. Escriche). Contents lists available at ScienceDirect International Dairy Journal journal homepage: www.elsevier.com/locate/idairyj https://doi.org/10.1016/j.idairyj.2019.104595 0958-6946/© 2019 Elsevier Ltd. All rights reserved. International Dairy Journal 101 (2020) 104595