Tailor-making specialized collagen peptides for high-end markets using by-products from the Norwegian poultry and salmon industry

SpectaColl aims at tailor-making collagen peptides from underutilized poultry and salmon by-product for specialized applications in food, health and pharmaceutical sectors. In the project, we have worked on targeted production of collagen peptides, and the first experimental design was aimed for optimization of important processing parameters that results in refined collagen peptides from poultry by-products. A total of 15 commercial food grade proteases were screened for their ability to selectively solubilize either myofibrillar or collagenous peptides. Other processing parameters such as temperature and hydrolysis time were also optimized. This has resulted in a novel multi-step process with high collagen peptide yield. In addition to yield, the enzymatic protein hydrolysis was also optimized against in vitro bioactivity (i.e., potential health promoting effect targeted towards diabetes). Similar screening and optimization of processing parameters is ongoing for demineralization and extraction of collagen peptides from salmon bone meal. Analytical methodologies for characterization of collagen peptides have also been developed. Collagen peptides have innate properties of forming a 3D intermolecular network leading to gelling. Hence, analysis methods to study peptide composition in such matrices are generally challenging. We have developed a sample preparation protocols as well as analysis protocols for studying molecular weight distribution of collagen peptides using size exclusion chromatography (SEC). This method has also been used to study a set of collagen peptides generated from chicken hydrolysates. Understanding the relationship between the molecular weight distribution and important quality characteristics (e.g., gelling capacity) is currently studied. We have further developed a chromatographic method for fractionation or isolation of bioactive peptides from crude collagen hydrolysates. This will form the basis for designing downstream processing approaches such as membrane filtration. In addition, other spectroscopic techniques such as NMR and FTIR has been used to characterize the hydrolysates generated in Spectacoll. Collagen peptides isolated from poultry by-products have been screened for health promoting effects toward both anti-diabetic activity as well as skin health. For antidiabetic activity, a set of collagen peptides generated from our novel multi-step hydrolysis process were screened for DPP-IV inhibition. This screening showed that, compared to myofibrillar peptides generated from a single-pot hydrolysis, the low molecular weight collagen peptides from multistep processimg are potent inhibitors of DPP-IV. Sequencing of the peptides constituting the bioactive fraction is underway. In order to evaluate the effect of collagen peptides on skin health, we have tested both crude collagen peptides as well as fractionated small molecular weight collagen peptides with an in vitro assay using skin cells (keratinocytes as well as fibroblasts). The preliminary results have shown that collagen peptides can have a beneficial proliferative effect on keratinocytes. Additional bioactivities in order to evaluate anti-inflammatory effects of the collagen peptides was performed and data analysis is underway. In a parallel effort, we have studied the emulsifying properties of large molecular weight collagen and their application in animal fat replacing oleogels. A mixture of poultry collagen with plant oils at a specific ratio have resulted in a promising and stable gel. Optimization of the collagen to oil ratio as well as characterization of rheological properties is underway. Results from Spectacoll has been communicated to the scientific community and public through presentations at relevant gatherings. Scientific articles as well as popular science articles aimed at the general public are under preparation. Moreover, a dedicated seminar on collagen peptides has been organized which involved more than 60 attendees from both academia and industry.

Enzymatic protein hydrolysis (EPH) is a biotechnological solution well-recognized as a central element of the circular bioeconomy mobilization in the food industry that can potentially transform food processing by-products to revenue streams. Collagen peptides are one of the potential high-end products that can be produced using EPH. However, in the traditional EPH process, collagen peptides either remain as insolubilized residues or they are extracted as minor constituents in complex crude hydrolysates. SPECtaCOLL aims at developing a novel and tuneable technology to tailor make collagen peptides from underutilized Norwegian agricultural and marine biomasses (i.e., poultry and salmon by-products). Moreover, the project is set to explore potential high-end application of the collagen peptides as ingredients in medical and food applications. SPECtaCOLL aims at realizing the potential of collagen peptides through the following key and highly interconnected pillars: 1) Development of novel and tuneable EPH process for selectively tailor making collagen peptides without the need for elaborate down stream processing 2) Development and application of advanced bioanalytical tools for EPH process optimization and product characterization 3) Exploring the potential of application of collagen peptides derived from poultry and salmon by-products as functional ingredients in medical, food and skin health applications SPECtaCOLL crosses value chains enabling synergies between the agricultural and marine sectors and combines advanced scientific competences in biotechnology, analytical chemistry, and medical sciences together with three industrial partners highly experienced in EPH. A successful implementation of results from SPECtaCOLL is expected to generate new scientific knowledge that can potentially set new standards and increase value creation of Norwegian agricultural and marine biomasses.