In this work halloysite (Hal) nanotubes were used as nanocontainers for salycilic acid (SA) in a perspective of its use in active packaging for food industry. The system Hal/SA was investigated for its ability to stabilize Hal suspensions by turbidimetry, its release kinetics in water by UV spectroscopy and its antibacterial activity against Pseudomonas fluorescens IMA 19/5 by Isothermal Micro Calorimetry (IMC). IMC is a sensitive and non-destructive technique and allows the study of a wide range of relatively slow processes (hours and days) in solutions. The system Hal/SA resulted to stabilize Hal suspension in water and to release SA in a controlled way over 50h. Moreover the SA released by Hal/SA showed an antibacterial activity at lower concentrations than free SA, likely due to the close contact of bacteria and Hal in the reaction vessel. Display omitted •Study of salicylic acid (SA) loaded into halloysite (Hal) system in aqueous medium.•Hal/SA system stabilizes aqueous Hal suspensions.•Hal/SA system releases SA in a controlled way over 50h.•The antibacterial activity of Hal/SA system is tested by calorimetry.•Hal/SA system shows antibacterial activity at lower concentrations than free SA.