This programme focuses on a number of different lipids and plant compounds, more specifically on the groups polyphenols and phenolic acids, glucosinolates, carotienoids, tocols and polyunsaturated fatty acids, and on natural antioxidants to prevent lipid oxidation and for the health potential associated with these compounds.
The research covers raw, stored and processed fruit, berries and vegetables, oils and meat rich in unsaturated fat. Studies of bioaccessibility and bioactivity are also being carried out together with relevant research centres in the fields of nutrition and medical research. This is a large project, which is divided into 5 sub-projects:
1. Polyunsaturated fat, lipid oxidation and antioxidants
2. Bioactive plant substances and antioxidants in fruit, berries and vegetables - chemical structure, quantity and antioxidant capacity
3. Pre- and post-harvest effects on the content of phyto-substances in processed fruit, berries and vegetables
4. Understanding how factors in food production affect fruit, berries and vegetables
5. Contributing to the understanding of how bioactive substances affect human health
Analysis methods for bioactive substances, oxidation products and antioxidant capacity are a central part of the programme. To characterise unknown substances present and to study whether they are changed during storage and processing, we have a range of chemical and instrumental analysis methods, focusing mainly on chromatography with different detectors (HPLC-DAD, LC-MSn and GC-MS). To measure antioxidant capacity, Nofima Mat uses the methods FRAP, ORAC, DPPH and total phenols. Analysis methods have been developed that can detect rancidity/oxidation at an early stage and that determine the quantity of specific volatile oxidation products.
Non-destructive measuring methods have been developed for flavonoids - which are good antioxidants - in fruit and vegetables. Using a hand-held instrument, the flavonoid content can be determined by repeated measurements at the same place, both during the plant's growth and in storage after harvesting.
Detecting early oxidation
The processing of raw materials with unsaturated fat is a challenge because lipid oxidation and the development of a rancid taste or smell can easily occur. The increasing focus on increasing the intake of omega-3 fatty acids in the general population, from either vegetable or marine sources, will give an even greater need for stabilising unsaturated fat throughout the value chain. The programme has built up solid competence in this field, so as to be able to help the food industry produce healthy, tasty and long-lasting food with a lower degree of lipid oxidation.
Can increase the antioxidant content in plant based food products
Both during the storage of fresh plant products and after processing, changes occur to sensory and health qualities (the content of antioxidants in fruit, berries and vegetables normally goes down after harvesting). We have carried out studies of bioactive components, focusing on antioxidants and especially vitamin C and polyphenols, in selected Norwegian products, and we have also improved traditional methods for processing and storage. New methods make it possible to both conserve and increase the antioxidant content of both fresh and processed products.
Increased understanding of bioactivity of foods
To help increase our understanding of bioactivity in food, we are studying the effects of extracts of fruit, berries, vegetables, isolated plant substances and bioactive lipids on the function of gastric epithelium cells, both in our own cell culture laboratory and in collaboration with medical and nutritional science centres. The programme contributes to competence in collaboration projects on human intervention studies, in which the health effects of lipids and fruit, berries and vegetables rich in antioxidants are studied.
