1. Material characteristics of silicone tubing
The majority of food-grade silicone tubing is composed of polysiloxane, which is a polymer material that possesses qualities such as high transparency, resistance to high temperatures, good chemical stability, non-toxicity, and odorlessness. In addition to having a strong tolerance to the majority of acids, bases, salts, and organic solvents, it can be utilized without risk in temperatures ranging from -50 degrees Celsius to 200 degrees Celsius or even higher. Because of these qualities
while the fact that high transparency makes it easier to observe the fluid that is contained within the tube, it also indicates that the material is more sensitive to the surrounding environment. It is possible for silicone tubing to undergo color changes under certain circumstances, which is the "yellowing phenomenon" that users are concerned about.
2. Some of the most common reasons why silicone tubes turn yellow
food-grade silicone tubing does not have a tendency to yellow; it may experience a small yellowing in certain conditions or when used for an extended period of time. The primary reasons are as follows:Although silicone is resistant to high temperatures, continuous exposure to liquids or vapors that are close to or above the maximum temperature limit can induce subtle changes in the internal chemical structure, resulting in a yellow or light brown tint. This can occur even if silicone is resistant to high temperatures.
Food residue: Oil, sugar, or protein that has adhered to the inner wall of the tube for an extended period of time may cause local discoloration as a result of oxidation reactions or high temperatures brought on by the tube.Using chemical cleaning products in an improper manner: Bleach or strong acid-base cleaning solutions have the potential to cause damage to the surface structure of silicone, which can result in discoloration or brittleness.
3.Methods to prevent yellowing of silicone tubing
In order to maintain clarity while extending the service life of silicone tubing, the following actions can be performed that are available:
It is important to maintain temperature control during use and to avoid prolonged contact with high-temperature liquids or vapors.
Protect yourself from ultraviolet light by selecting UV-resistant coatings or shade sleeves for usage outside.
In order to prevent the accumulation of food residues, it is important to do routine cleaning using warm water and a neutral detergent.
Select tubing of the highest quality: Invest in food-grade silicone tubing of the highest quality that satisfies the requirements of the FDA or LFGB.
Proper storage involves ensuring that the item is kept dry, away from light, ventilated, and away from prolonged exposure to high temperatures or direct sunlight.
4.Can yellow silicone tubing still be used?
The use of silicone tubing that has been somewhat yellowed is typically not detrimental to the safety of food and can be continued. It is recommended, however, that it be replaced in a timely way under the following circumstances:
Surface hardening or brittleness can lead to the leaking of liquid or the fracture of the material.
It is possible that microbiological or chemical alterations are the cause of yellowing that is accompanied by an odor.
The color is extreme yellowish or brown, and the material has apparent signs of aging, both of which may have an impact on the operation of the conveying system.When it comes to medical, infant feeding, and high safety food situations, it is essential that even a small yellowing be changed in order to guarantee that hygiene and safety are maintained.
5. Practical application and usage suggestions
When it comes to practical applications, the yellowing problem of silicone tubes may be effectively controlled via the utilization of appropriate use and the maintenance of frequent cleaning:
In the process of brewing beer, yellowing can occur when 80 degrees Celsius wort is used for an extended period of time; however, yellowing can be reduced with regular cleaning and temperature regulation.
During the process of feeding an infant, high-quality silicone milk tubes are subjected to a decolorization treatment and are replaced on a regular basis to maintain adequate hygiene and safety.
High temperatures, UV radiation, chemical cleaning agents, and food residues are some of the factors that might cause a mild yellowing of food-grade silicone tubing. However, under normal usage settings, food-grade silicone tubing does not have a tendency to yellow. Yellowing can be effectively delayed by selecting pipes of high quality, using them in a reasonable manner, and cleaning them on a regular basis. This will ensure that the pipes continue to be transparent, aesthetically pleasing, and safe over the long run.
