Most people have heard that they should avoid eating poppy seed bagels or muffins before a drug test as they may cause a positive reading for opiates.
There is some truth to this, because the tiny black seeds contain small amounts of morphine and codeine and could come up on a sensitive drug test. Now, researchers have studied how different treatments can affect levels of opiates in poppy seeds.
For thousands of years, people have grown poppies both for their colourful flowers and analgesic properties. The plant is the source of opium, which has long been used as a medicinal and recreational drug.
Although opium comes from a sap-like substance that surrounds the capsule encasing the seeds, some can be transferred to the seeds during handling.
As a result, scientists have detected low levels of opium alkaloids, such as morphine, codeine and thebaine, in poppy seeds.
Benjamin Redan and colleagues wanted to measure levels of these opiates in commercially available seeds and determine whether different treatments, including heating or baking in a muffin, could affect their levels.
The study, published in ACS’ Journal of Agricultural and Food Chemistry used mass spectrometry to measure the levels of three major opium alkaloids in 15 samples of commercially available poppy seeds, and detected large variations in opiate concentrations.
Heating the seeds at 200ºC for at least 40 minutes degraded most of the alkaloids. However, baking the seeds within or on top of a muffin for 16 minutes at the same temperature didn’t significantly change morphine, codeine or thebaine concentrations in the seeds, possibly because the internal and external temperatures of the muffins reached only 99.4ºC and 136ºC, respectively.
Although this study showed that heating poppy seeds could reduce opiate levels, the researchers say this treatment would likely alter the sensory properties or reduce the shelf life of the seeds.