Pea protein-systems for plant based protein products, The eﬀect of insoluble and soluble lentil fractions on rheology, microstructure and gelation properties of heat induced pea protein gels
Examensarbete för masterexamen
Biotechnology (MPBIO), MSc
Mitigating climate change is one of today’s generations largest challenges and the devastating eﬀects that might follow can already start to be seen. As one of the largest contributors to climate change as well as the largest contributor to eutrophication, the food industry plays a key role in combating these issues. One way to reduce the environmental impact of our food is to reduce the consumption of animal derived foods and replace it with plant based foods, a shift in diet often referred to as the protein shift. However,for people to accept this dietary change, new products with similar nutritional value together with an equal or better consumer acceptance needs to be developed. Peas (Pisum sativum) has recently gained an increasing interest due to its high protein content and overall high nutritional value. But in order for better utilisation of peas and pea protein, further research is needed. Heat induced protein gelation is a common process in the food industry. Understanding of this process together with characterisation of functional properties of relevant proteins can help in product development and optimisation of new and existing products. Research on heat induced pea protein gelation has so far been limited, especially regarding the eﬀect of adding other food ingredients. In this context, a basic understanding of pea protein gelation and the eﬀect of adding green lentil (Lens culinaris) fractions rich in soluble ﬁbre (soluble-fraction) or insoluble ﬁbre and starch (insoluble-fraction) prior gelation can be helpful. By analysing rheology, texture, gelation and microstructure, a good overview of the behaviour of these systems can be obtained and help in the developing of new plant bases foods. The addition of insoluble- and soluble-fractions extracted from lentils was found to aﬀect the texture, rheology and microstructure of heat induced pea protein gels. Addition of insoluble-fraction resulted in an increase of the fracture stress, Young´s modulus and storage modulus and many of the eﬀects seemed related to the presence of starch. The addition of soluble ﬁbre-fraction decreased the fracture stress and Young´s modulus of the gels but increased the storage modulus. Both fractions aﬀected the microstructure of the gels. These results can help in development of new plant based foods in which protein gelation is critical for obtaining a desired texture.
gelation , light microscopy , peaprotein , uni-axialcompression , ﬁbre , dynamicrheology , starch