The seeds and berries of native New Zealand plants have proven to be an unusual source of beneficial lipids, which, among other things, are an important supplement to human food and nutrition.
Over the past two years postgraduate student Zirsha Wharemate has researched the fatty acid profile of the seeds and berries of 46 native plants for her masters degree in Nutritional Science.
Plant lipids are useful for providing energy and taste benefits in food, as well as providing fatty acids essential to humans. They also form an important part of animal feed and are used by industry in protective coatings and detergents.
It was interesting to discover that seeds of certain native plants are rich in the fatty acids that are suitable for high temperature cooking oils, Ms Wharemate says.
Seeds from Seven Finger and Five Finger plants were found to contain high levels of oleic acid, an important component of high temperature cooking oils such as sunflower oil. These seeds also have a low content of saturated and polyunsaturated fatty acids, which are considered to be less healthy for humans as well as less stable at high temperatures.
Chatham Island forget-me-not, miro, flax, snowberry, New Zealand cabbage tree, New Zealand passionfruit, titoki, totara and kahikatea were found to contain an unusually high fatty acid content, similar to levels currently found in seeds such as soybean and peanuts.
Ms Wharemate says some beneficial fatty acids are found in significant quantities in fish oils but as many people find the odour and taste that fish oils bring into food undesirable, it would be beneficial if a plant substitute could be found. “It is too early to tell if it would be viable or feasible to extract these oils from New Zealand plants but this research certainly presents some positive possibilities and warrants further study.”
Ms Wharemate says she was interested in studying these lipids because they are essential to life. She chose to research New Zealand natives because she has always been interested in how Mäori have used their medicinal and healing properties. As most New Zealand plants are unique to this country, Ms Wharemate says there is the potential they contain exciting components not found anywhere else in the world.
This lipid research is one of several food research and analysis projects conducted within the Institute of Food Nutrition and Human Health’s nutrition laboratory and was funded by a Tuapapa Putaiao Mäori Scholarship from the Foundation of Research Science and Technology.
Nutrition and Dietetics