Peixoto, AndreiaSantos, SusanaRodrigues, JoãoSaraiva, MargaridaCorreia, Cristina BeloBatista, RitaNovais, CarlaAntunes, Patrícia2026-02-092026-02-092025-05-08http://hdl.handle.net/10400.18/10855Contaminated surfaces in food-processing environments represent a significant food safety risk, making the monitoring of hygiene on hands and food-contact surfaces a priority. This study aimed to assess the occurrence and diversity of hygiene indicator bacteria in Portuguese foodservice facilities and to evaluate their association with biocide use. A total of 1,128 hand and surface samples were collected from 107 facilities, with bacterial identification performed by MALDI-TOF-MS and information gathered on the type and concentration of biocides used. More than half of the samples showed unsatisfactory hygiene results, mainly due to high total viable counts and Enterobacteriaceae levels. Forty bacterial species were identified, with Enterobacter cloacae, Klebsiella pneumoniae and Klebsiella oxytoca being the most prevalent. Hygiene performance varied according to the type of biocide applied, with quaternary ammonium compound-based products showing greater effectiveness. Despite appropriate biocide concentrations, the persistence and diversity of bacteria highlight the need to further investigate microbial susceptibility and persistence in order to improve hygiene practices.engHygiene ChallengesFoodservice UnitsFood SafetyHigiene SuperfíciesDiversidade BacterianaSegurança Alimentarconference object