Amino Acid Modifications during the Production (Shearing, Sterilization) of Plant-Based Meat Analogues: An Explorative Study Using Pet Food Production as an Example

Shear cell technology is a promising method for the production of meat analogues. Meat analogues are also studied as alternative proteins for dogs and cats, which require high-quality protein. This study monitored the effect of shearing, using shear cell technology, and sterilization (26 min at 125.5 °C) on selected amino acids, advanced glycation end products (AGEs), lysinoalanine, o-phthalaldehyde-reactive lysine, as well as oxidation markers, free thiols, and dityrosine, in soy protein- and pea protein-based meat analogues. These are compared with animal-based pet foods. Processing resulted in modified amino acids, especially cysteine. Reductions in amino acid levels were higher in the soy-based meat analogue, but markers indicated more pronounced oxidation in the pea-based meat analogue. AGEs and lysinoalanine were not formed on shearing, only during sterilization. Despite extensive thermal treatment, the effects of processing on the protein quality of plant-based products were comparable or less than those in animal-based pet food.