Influence of different sources of vegetable, whey and microalgae proteins on the physicochemical properties and amino acid profile of fresh pork sausages

The purpose of this study was to evaluate changes in the physicochemical properties and amino acid profiles of pork sausages prepared by including vegetable protein sources (beans, peas, and lentils), microalgae (Chiorella and Spirulina) or whey, as compared with a control (soy protein). Significant differences were found for all the studied parameters. The protein content was significantly lower in sausages made with pea protein compared with the control. Colour parameters changed significantly after the incorporation of microalgae proteins. Moreover, significant differences among treatments were observed in the amino acid profile. The inclusion of spirulina proteins resulted in an increase in the total amino acid content and the ratio of essential/non-essential amino acids. Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) allowed pork sausages to be classified according to the protein source, in comparison with soy (control). Textural parameters (chewiness, gumminess and hardness) followed by colour and pH were the most discriminant parameters. Considering texture traits, physicochemical parameters and amino acid profiles across treatments, proteins from legumes and whey provided profiles closer to that of soy. However, although microalgae-derived proteins altered the colour and texture, they provided nutritionally favourable profiles, thus suggesting that seaweeds could also be used to enrich pork sausages, as an alternative to soy protein.