Stable Isotope Analysis

What are Stable isotopes?

Each atom contains protons and neutrons in its nucleus, in which the number of protons defines the element (i.e. hydrogen, carbon, nitrogen, etc.) and the sum of the number of protons and neutrons defines the atomic mass. The number of neutrons (neutral particles) can vary and these are different isotopes of one element. For example, most carbon atoms have six protons and six neutrons with an atomic mass of 12, however some are “heavy” and have seven neutrons, with an atomic mass of 13. Stable isotopes do not decay into other elements – they are “stable” through time. In contrast, radioactive isotopes (e.g., 14C) are unstable and will decay into other elements.

What are Stable isotopes?

vEach atom contains protons and neutrons in its nucleus, in which the number of protons defines the element (i.e. hydrogen, carbon, nitrogen, etc.) and the sum of the number of protons and neutrons defines the atomic mass. The number of neutrons (neutral particles) can vary and these are different isotopes of one element. For example, most carbon atoms have six protons and six neutrons with an atomic mass of 12, however some are “heavy” and have seven neutrons, with an atomic mass of 13. Stable isotopes do not decay into other elements – they are “stable” through time. In contrast, radioactive isotopes (e.g., 14C) are unstable and will decay into other elements.

How can we use isotopes?

The stable isotope ratio varies with different attributes of food, including farming practices, feed diets, and geographical origin. For example, wild-caught salmon contains more 15N compared to farmed; and different feed diets of cattle also charge their 13C ratio.

With the use of Stable Isotope Ratio Mass Spectrometry, the food or products are chemically broken down and injected into a mass spectrometer. The relative abundance of each isotope is measured by their deflection through a magnetic field.

Once the stable isotope signatures have been detected, they are then compared against a reference database.

With the use of Stable Isotope Ratio Mass Spectrometry, the food or products are chemically broken down and injected into a mass spectrometer. The relative abundance of each isotope is measured by their deflection through a magnetic field.

Once the stable isotope signatures have been detected, they are then compared against a reference database.