Hazelnuts are one of the up and coming crops grown commercially in New Zealand with thousands of hazelnut trees being planted throughout the country, with the highest proportion being in Canterbury.
Scientists report that there are health benefits for people who regularly eat nuts, such as hazelnuts.
In order to encourage people to eat more nuts it is important that the nuts are roasted to the level of darkness people prefer.
Researchers from the Food Group at Lincoln University have been working with The Hazelnut Company (a co-operative of hazelnut growers) to conduct roasting trials and to set up a (consumer appreciation) trial.
Steve Connor, Director of The Hazelnut Company, is at Lincoln University as part of a Royal Society Teaching Fellowship and he is working with biochemist, Dr. Geoff Savage on this project.
A conveyer oven, owned by the company, was shifted to Lincoln and combinations of conveyer speed and temperature were trialled with four different roasting levels being selected.
Once the nuts were prepared a sensory evaluation session was set up to cater for the over 60 volunteers. These tasters came from the staff and students of the Lincoln campus.
"The results were remarkable because they were so definite," said Steve.
The tasters were given the four differently prepared nuts in a random order and were asked to rate their appearance, texture, flavour and overall impression on a scale of 1 9. The average of each roasting level for all four attributes were compared and the results were quite revealing.
The first level was the raw hazelnut with the skin (pellicle) on. The next level was blanched which was the minimum cooking to allow the pellicle to be removed. The other two levels were light and full roasting. This required the slowest setting on the conveyer oven for the chosen temperature.
"As the roasting level increases so does the approval rating. This pattern was repeated for all four attributes and gives a great basis on which to build a marketing plan."
Though a number liked the raw nut, Steve, himself, agrees with the majority and says the full roast deserves to be top.
"This level of roasting maximises the unique flavour and texture of the hazelnut," he said.
He was greatly encouraged by the number of positive comments made by the tasters.
The company is currently building the processing equipment and intends to commence selling to the public early this year.
"Something grown locally that tastes so good and yet is great for you must take off." he said.
For further information contact
Ian Collins, Journalist, Lincoln University, Canterbury
Tel: (03) 3252811 ext 8549.
Email: Ian Collins
Janette Busch, Technical Writer, Animal and Food Sciences Division, Lincoln University, Canterbury
Tel: (03) 325 2811 ext 8114
Email: Janette Busch