Food Control 131 (2022) 108416 Available online 10 July 2021 0956-7135/© 2021 Elsevier Ltd. All rights reserved. Antimicrobial and antioxidant effect of lyophilized Fucus spiralis addition on gelatin flm during refrigerated storage of mackerel Marcos Trigo a , Pedro Nozal a , Jos´ e M. Miranda b , Santiago P. Aubourg a, * , Jorge Barros-Vel´ azquez b a Department of Food Science and Technology, Marine Research Institute (CSIC), C/ E. Cabello, 6, 36208, Vigo, Spain b Department of Analytical Chemistry, Nutrition and Food Science, School of Veterinary Sciences, University of Santiago de Compostela, Avenida Carvallo Calero, S/n, 27002, Lugo, Spain A R T I C L E INFO Keywords: Fucus spiralis Gelatin packaging Scomber scombrus Refrigeration Microbial development Lipid damage ABSTRACT Lyophilized alga Fucus spiralis powder was incorporated into a gelatin-based flm and employed as a packaging system for mackerel (Scomber scombrus) muscle portions throughout a 9-day refrigerated storage period at 4 ◦ C. In global terms, a progressive loss of quality could be observed in fsh muscle with increasing storage time. Comparisons between batches allowed us to conclude an inhibitory effect of F. spiralis-containing flms on mi- crobial activity (assessment of aerobes, psychrotrophs, and proteolytic bacteria) and on lipid hydrolysis (as determined by free fatty acid formation) in mackerel muscle. The presence of the lyophilized macroalga in the packaging flm also led to a higher retention of primary (peroxides) and secondary (thiobarbituric acid reactive substances) lipid oxidation compounds, while the formation of fuorescent compounds (interaction compounds between lipid oxidation compounds and nucleophilic molecules present in the fsh muscle) decreased. Both antimicrobial and antioxidant effects were more intense when the concentration of alga in the packaging flm was increased. The preservative effect resulting from the presence of F. spiralis in gelatin-based flms demon- strates the potential employment of such bioactive flms to improve the retention of fsh quality and enhance its commercial value. 1. Introduction The consumption of marine species provides many benefts to human health, as they are important sources of polyunsaturated fatty acids (PUFA), high-quality proteins, minerals, and lipophilic vitamins (Tilami & Sampels, 2018). However, their high water and non-protein nitrogen contents, soft muscular and skin structure, low content of connective tissue, and poikilothermic nature make marine species perishable commodities ( ¨ Ozo˘ gul, 2010). Lowering the temperature with ice or mechanical refrigeration is the most common way of retarding microbial and biochemical spoilage of fsh. Although widespread, neither tech- nique can guarantee the retention of fsh quality, especially when rela- tively long storage times are applied or when the cold chain is not strictly maintained. Consequently, advances in refrigeration processes have been developed to circumvent these scenarios (Campos, Gliemmo, Aubourg, & Barros-Vel´ azquez, 2012). One such preservation technology is packaging. Packaging maintains food freshness and preserves foods during distribution and storage from adverse situations, including water vapor, microorganisms, gases, odors, dust, and mechanical shock and vibrations (Mihindukulasuriya & Lim, 2014; Dehghani, Hosseini, & Regenstein, 2018). Interestingly, currently existing packaging technologies work together with a number of phys- ical, chemical, and biological processes and agents to limit both mi- crobial activity and biochemical breakdown in foods (Gim´ enez, L´ opez de Lacey, P´ erez-Santín, L´ opez-Caballero, & Montero, 2013; Kuley, ¨ Ozo˘ gul, & Polat, 2020). Biodegradable and edible materials derived from plants and animals, including peptides, polysaccharides, and lipids, are proftable alterna- tives to synthetic packaging flms (Umaraw et al., 2020). Among the polysaccharides, gelatin obtained from diverse animal sources (porcine, bovine, and fsh) has been applied effectively in active packaging stra- tegies for its flm-forming ability (Etxabide, Uranga, Guerrero, & De la Caba, 2017). Thus, gelatin-based coating and packaging flms reduce oxygen, oil, and moisture transport (Pavli, Tassou, Nychas, & Choria- nopoulos, 2018) and can be used to reduce oxidation events, preserve favor, and improve the color stability, taste, and aroma of foods (Cuter, * Corresponding author. E-mail address: saubourg@iim.csic.es (S.P. Aubourg). Contents lists available at ScienceDirect Food Control journal homepage: www.elsevier.com/locate/foodcont https://doi.org/10.1016/j.foodcont.2021.108416 Received 21 February 2021; Received in revised form 3 June 2021; Accepted 9 July 2021