The effect of drying processes on the microbial load of laundry

BRITTA BRANDS, MARLITT HONISCH, SANDRA WEGNER, DIRK P BOCKMÜHL*
*Corresponding author
Rhine-Waal University of Applied Sciences, Marie-Curie-Str. 1, 47533, Kleve, Germany

Abstract

Textiles are potential vectors for transmission of infections in the domestic environment. In textile reprocessing the drying process is inextricably linked to the washing process. In this study the antimicrobial effect of different drying processes, and their role in domestic laundry hygiene was investigated by drying artificially contaminated textiles indoors and outdoors on the clothesline or in tumble dryers. All types of drying proved to reduce the germ load on the fabrics significantly; the highest effect was observed drying on the clothesline outdoors.


INTRODUCTION
Microbial contaminations on garments and textiles are sought to be removed by laundering to avoid unwanted microbiological problems such as risk of infections or malodour production. Studies so far have mainly focused on the laundry process. The consecutive drying process might further affect the remaining microbial load and should be taken into account when assessing the microbiological quality of textiles.
This study investigated the antimicrobial efficacy of different drying methods and provides information on the microbiological impact factors after laundering.

 

MATERIALS AND METHODS

The method for determining the microbial load on textiles was adapted from standard methods for testing chemical disinfection processes in laundering (1).

 

Preparation of germ suspensions
The germ suspensions were obtained in accordance with Honisch et al. (2): for Bacilllus subtilis (DSM 10) and Pseudomonas fluorescens (DSM 50090), 10 mL sterile triptic soy broth (TSB, Oxoid, Germany) and for Saccharomyces cerevisiae (DSM 1334), 10 mL sterile ...