What is required for proper sample preservation?

Immediate refrigeration upon collection is essential for proper sample preservation as it slows down the metabolic processes of microorganisms and reduces the degradation of biochemical constituents in the sample. Many samples, especially those collected from environmental settings, are susceptible to changes due to increased temperature, which can lead to alterations in the sample's composition. By cooling the sample quickly, the integrity and accuracy of the analysis are enhanced, ensuring that the results reflect the true characteristics of the sample at the time of collection.

While the use of chemical preservatives can be beneficial in certain scenarios, they are not universally necessary for all types of samples. Similarly, while storage in a dark environment may help in specific cases to prevent degradation caused by light exposure, it does not address the immediate concern of microbial activity and chemical changes that can occur with temperature variations. Sealing samples in plastic containers is important for avoiding contamination and loss of volatiles, but it does not itself preserve the sample effectively if the temperature is not managed. Immediate refrigeration is a critical step to maintain sample quality for reliable analysis.