Málfríður Bjarnadóttir at Matís will defend her master's thesis on Friday 2 June at 13 but in his project, Málfríður investigated whether it was possible to obtain protein from silver, which could, for example, be suitable for vegetarians.
Exact location:
- Matís
- Vínlandsleið 12
- 109 Reykjavík
- Meeting room 311
- Project for a master's degree in food science worked at Matís
Abstract
The need for a secure food supply is constantly growing in line with population growth. In modern society, there is also an increasing emphasis on a healthy diet, protection of the environment, utilization of natural ingredients and sustainability. Thus, for example, a diet that excludes animal products is becoming increasingly popular. For this reason, it is important to find new sources of food, especially protein sources, which contain the essential amino acids that the human body needs. Salt (Palmaria palmata) belongs to the class of red algae that contain a high percentage of good quality proteins. The extraction of proteins from silver, on the other hand, is limited by a strong cell wall consisting mainly of β- (1 → 4) / β- (1 → 3) -D-xylans. In order to overcome this obstacle, it is necessary to break down this cell wall. Different ways of doing this have been explored along with different methods for assessing protein content. The aim of this project was to examine the effect of different enzymes on protein recovery from P. palmata. Enzyme stimulation with both protease and xylanase was examined. Hydrolysis with xylanase yielded the best protein yields and showed that protein extract from P. palmata contains all the vital amino acids that the human body needs and is therefore cost-effective as a protein source in food. A new nitrogen coefficient was calculated for the samples analyzed for amino acid composition and the coefficient varied greatly between samples. The coefficient was significantly lower than 6.25 which is the coefficient normally used. These results suggest that using a nitrogen content of 6.25 for seaweed such as P. palmata may cause an overestimation of protein levels. This makes it difficult to compare results between studies. Hydrolysis with protease with or without xylanase resulted in a higher proportion of peptides, amino acids and small proteins in the liquid after filtration and therefore the distribution of proteins was more even between samples. Protease hydrolysis is therefore not good for isolating proteins by the method used in this study. However, their fluid extracts showed good in vitro antioxidant activity and ACE inhibitory activity. This suggests that the use of protease on P. palmata is a good way to produce and extract bioactive substances.
- Supervisor: Rósa Jónsdóttir, Matís
- Supervising teacher: Björn Viðar Aðalbjörnsson, University of Iceland, Matís
- Co-supervisor: Hörður Kristinsson, Matís
- Examiner: Hákon Hrafn Sigurðsson, University of Iceland