CULTURE OF PACIFIC DULSE Palmaria mollis IN LAND-BASED SYSTEMS

The red seaweed Pacific dulse (Palmaria mollis) is found in the low inter-tidal and subtidal zones on the US West coast. Atlantic dulse, P. palmata, has been used as a human food for centuries and is still harvested as an ingredient in local dishes and for health supplements. P. mollis contains up to 20 % protein (dry weight) and is a rich source of trace minerals, such as iodine.

Research at the Hatfield Marine Science Center and the Food Innovation Center, Oregon State University, has focused on expanding development of Pacific dulse as a sustainable, healthy human food. Reduction in the economic costs of land-based culture has been achieved by simplification of the nutrient mix used to fertilize the dulse. Batch culture of dulse, without a requirement for a continuous supply of seawater, has proven possible with no adverse effects on growth rates. In addition, successful use of artificial seawater for dulse culture will allow dulse farming at locations distant from sources of seawater but close to urban centers where demand is likely to be highest.

Sensory evaluations of dulse alone and as a food ingredient have been undertaken at the Food Innovation Center. Dulse plants that differed in appearance due to culture conditions and genetic factors, were on average found to be similar in their likeability by panelists, although individual panel members differed in their preferences. Dulse added as an ingredient to salad dressing and rice crackers were highly liked by panelists.

Overall, we have found that dulse can be cultured under batch conditions using artificial seawater and with additions of a simplified nutrient mix. The potential for dulse as a human food or as a component of animal feeds is considerable. Dulse could be a valuable source of protein in a future with limited supplies of freshwater and an increasing human population.