Fruit stones usually end up in a bin, mainly for their lack of taste. There are a growing number of scientists who point to their nutritional and health-promoting properties. The researchers from the UWM have also investigated the issue. Ewa Kucharczyk M.D. and Michał Majewski, PhD in pharmacological science, both from the Pharmacology and Toxicology Department of the Faculty of Medicine have begun their study on raspberry pomace.
- Such studies have never been conducted in Poland. We had an idea to move in that direction. Raspberries and blackberries are grown in Poland on a large scale. We experiment with raspberries, because the total mass of their pressings contains 50% of seeds. These seeds, in turn, can yield 10-30% of oil – explains dr Ewa Kucharczyk.
Raspberries in themselves are a tasteful fruit. They are appreciated by dieticians, as they contain a lot of vitamins and minerals – including magnesium, calcium and iron, as well as many other healthy substances. Can they still be healthier? It is quite possible.
- When we eat various fruits, their seeds go through our system without being taken advantage of. We are going to crush the seeds so that the oil and other substances they contain become available to the body. This is how we will find out if they affect our bodies – says Michał Majewski, PhD.
The scientists will check how the compounds present in raspberry seeds – like oil, proteins and fatty acids – affect the vascular system, which is responsible for monitoring the blood pressure and metabolism.
- Obesity causes the dysfunction of vascular endothelium, which in turn leads to hypertension – adds Michał Majewski.
The examination will be carried out on laboratory rats, which constitute a good model for such research and have been used for a long time. The UWM scientists will separately examine the raspberry fruit, the raspberry seeds and the pulp. For crushing the seeds, they will make use of laboratory grinders connected to liquid nitrogen to lower the temperature of the seeds.
- Grinding the seeds in domestic conditions would not make sense, as all of the oil extracted from the seeds would oxidise. This is why it needs to be done in low temperatures – explains Michał Majewski.
The rats will be divided into four groups. The first will be fed the seeds, the second will get the pulp, the third will be given dried fodder, and the fourth will be the control group. They will continue on this diet for one month. The research begins in November. No later than two weeks after the nutrition phase is over, the scientists will know how raspberry pressings affect the blood vessels. That is, however, not the whole study.
- I believe we will have the complete data by March of next year – sums up Michał Majewski, PhD in pharmacological science.
In the food industry, the products containing fruit are stripped of stones and seeds. This is also how we process them at home.
- This study is quite important, because the conclusions we arrive at may influence food production in the future – emphasizes dr Ewa Kucharczyk.