By OLLY EADES & ROSS WEIR
Preventing smelly clothes, has founded a multi-million dollar industry. Between washes, performance fabrics and treatments are used to keep unpleasant odour at bay. Odour control is a core technology in many textile industry sectors. Use in sport is arguably the toughest challenge. There are a range of technologies on the market to prevent apparel smelling and Progressive can help you test them.
Wake up and smell the coffee
Clothes develop their own smell as they become soiled with sweat. When we exercise, we perspire, but this has very little smell of its own. Our body has two different types of sweat glands: Eccrine (saline water) and Aprocrine (saline water, proteins and fatty acids). It is the protein and oils within Aprocrine sweat that acts as a food source for bacteria present on the skin. In a warm and moist micro climate the bacteria can multiply, digesting the available material. The result is odorous fatty acids which evaporate off the fabrics. When they evaporate into the air around us, we can smell them. The industry offers two distinct preventions.
Not how we do it at Progressive!
The proteins, the bacteria or the odour molecules can be absorbed or bound to the fabrics material, preventing evaporation and associated odour. One method is the use of activated carbon, which allows the binding of odour molecules to the chemically active surface of the carbon. This is quite similar to how wool, known for its anti-odour ability, prevents smells from developing too. Many people wrongly presume that wool has an anti-microbial effect to achieve its anti-odour properties.
The bacteria is limited from multiplying (anti-microbial).Odorous molecules are not produced in great numbers. The prevention method relies on killing bacteria, which is achieved using naturally occurring ions or enzymes. Silver and copper are commonly known metals that produce free ions, these bind to bacterial cell surfaces. This disrupts the cell membrane function killing the cell. The enzyme approach, embeds an antibacterial agent into a material, kills bacteria in a similar way.
The success of such technologies in limiting odour can be examined. Established lab standards (e.g. AATCC 100-1993, JIS L 1902-1998, ISO TC38 WG23) and/or novel non-standard test methods can be used. These measure the success of the bacterial population (cell count) or analyse the amount and type of odour molecule released (e.g. mass spectrometer methods).
However, true performance is found in how the human nose interprets any odour. Progressive provides sensory testing protocols to support the industry. Prior studies have aided the development of our methods. For example, researchers looked at how best to test and evaluate odour on fabrics and how different fiber types influence the intensity of odour (McQueen et al. 2007a, 2007b). Others seek a chemical basis for the smell of sweat that can be found in clothing (Munk et al. 2000), or identify compounds often associated with odour and variation between textiles (Callewaert et al. 2014; McQueen et al. 2008, 2014 Munk et al. 2001). Based on these studies, Progressive has developed sensory tests using consumer panels of non-trained subjects, which provides reliable insight on how ordinary consumers relate to such odours in garments.