Improving Krill Oil Standards

November 8, 2013
Gabriel I. Giancaspro

A krill oil monograph will improve identity and purity testing, and help curtail adulteration.

Krill oil is described as a red, viscous oil with seafood odor, derived from Antarctic krill, which are shrimp-like marine crustaceans of the species Euphausia superba. Krill oil has attracted the attention of both the food and dietary supplements industries, especially for its high content of phospholipids-in particular, omega-3 fatty acids EPA and DHA in their phospholipid forms. Krill oil also contains the carotenoid astaxanthin, a naturally occurring antioxidant that gives krill oil its red color and that acts as a natural preservative.

FDA has issued GRAS notifications for krill oil to be used in those foods that are otherwise commonly supplemented with fish oil, as well as a variety of processed foods, including breakfast cereals, cheeses, frozen desserts, and processed fruit juices and fruit beverages.1 These GRAS notices, plus a plethora of clinical studies linking this ingredient to potential health benefits, have turned krill oil into a high-value commodity, triggering the need to protect its authenticity through stringent quality standards that uniquely define the identity and purity of this ingredient.

In September 2013, the U.S. Pharmacopeial Convention (USP), a non-profit scientific organization that sets standards for the identity, quality, and purity of pharmaceuticals, food ingredients, and dietary supplements, published a new krill oil monograph in the eighth edition of the Food Chemicals Codex in an effort to bring confidence and consistency in testing krill oil as a food additive. The new standard is effective December 2013.

Individuals trying to adulterate krill oil have used other sources of phospholipids in their products without labeling them accordingly. Previous quality standards for krill oil did not offer tools to differentiate with certainty what these other phospholipid sources were, and they did not offer tools to quantify each distinct source. Key components of USP’s krill oil monograph include a Phosphorus Nuclear Magnetic Resonance (P-NMR) analysis and a Proton Nuclear Magnetic Resonance (H-NMR) analysis of the phospholipids contained within krill oil. With the NMR analyses, it is possible to determine the types of phospholipids specifically present in krill oil and quantify them, offering manufacturers an opportunity to test their products in a way that would add consistency to the industry standards.

The monograph also lists specific tests for inorganic impurities such as arsenic, lead, and mercury, as well as a test to quantify the astaxanthin content in krill oil. A USP Krill Oil Reference Standard Material for use with the FCC monograph was published in June 2013.

USP Reference Standards are highly characterized physical specimens that manufacturers can use to help ensure the identity, quality, and purity of food ingredients and dietary supplements. USP’s Reference Standards collection consists of more than 3000 items ranging from food ingredients, drug substances, dietary ingredients, biologics, excipients, related impurities, and calibrators.

For more information about the krill oil monograph and the accompanying Reference Standard Material, visit: