Modification of functional properties of potato and oat protein
Examensarbete för masterexamen
Biotechnology (MPBIO), MSc
In order to improve the sustainability of the food industry, there is a large interest in making side-flows more utilizable and increasing their value. Two side-flows of interest for this are potato and oat protein, since they are prevalent in by-products from common food industries and have good nutritional qualities. This project aimed to evaluate different chemical and enzymatic treatments for improving the functional properties of potato and oat protein concentrates with the intention to use them in high protein food products. The evaluation of functional properties after different treatments included trypsin-treatment for enzymatic hydrolysis, transglutaminase-treatment for enzymatic cross-linking, sulfitetreatment for reduction of disulfide bonds as well as acetylation and succinylation for replacement of functional groups on the peptide chains. The results indicated that enzymatic and chemical modifications could provide useful methods for improving functional qualities, such as solubility, emulsifying properties and foaming properties, in the studied proteins. Sulfite-treatment and trypsin-treatment of potato protein concentrate were further studied with a focus on gel and film formation. Studies on gel formation showed that sulfite-treated potato protein concentrate could form stable gels through heating, in contrast to untreated and trypsin-treated potato protein, which did not form gels. Sulfite-treated gels were also used for film formation by heated high pressure pressing, however no differences were seen between the films made of untreated and sulfite-treated protein concentrate in this study.
Biologiska vetenskaper , Livsmedelsvetenskap , Hälsovetenskaper , Livsvetenskaper , Biological Sciences , Food Science , Health Sciences , Life Science