All enzymes used in Megazyme products have been subject to extensive stability studies and not affected by short term ambient shipping and are of high stability in the form which they are supplied.
Megazyme ships thousands of enzyme products at ambient temperature without any issues however for longer term stability the individual components should be stored as stated on the individual bottles / vials as soon as the products are received.
Most Megazyme kit products are supplied with a standard reference analyte (e.g. the acetic acid kit K-ACET contains an acetic acid standard in bottle 5). The performance of the kit can be assessed by testing the supplied standard and it is expected that the reaction is complete in the time stated in the kit data booklet and that the expected value for the standard analyte is obtained within the experimental error allowed.