Impact of enzymatic hydrolysis time on the palatability of liquid flavor enhancers in dry pet foods

The pet food industry is rapidly growing, driven by innovation and a diverse product portfolio designed to meet evolving markets demands. A key determinant for this industry is pet food palatability, which plays a pivotal role in product performance and consumer satisfaction, based on pets’ preference. However, pet food manufacturing processes can negatively affect sensory attributes resulting in less palatable food. To address this issue, the industry uses specific flavor enhancers, known as palatants, to increase product palatability. These palatants are tipically produced through enzymatic hydrolysis of protein-based raw materials, followed by thermal treatment to promote Maillard reaction and enhance flavor. This project was conducted in the Research & Development Department at Kemin Nutrisurance Europe s.r.l., in Veronella, Italy. The primary objective was to evaluate the effect of hydrolysis time variations on liquid palatant palatability in dry pet food, with the aim of defining stricter tolerance limits for this process parameter. The study focuses on Kemin’s top-performing super premium liquid palatant, considering one formulation each for dogs and cats. Laboratory-scale prototype production involved increasing and decreasing hydrolysis time compared to Kemin’s current standard. Palatability tests (i.e., versus tests) were externally performed to evaluate pets’ preference for the prototypes over original formulas. These tests were supported by comprehensive chemical and physical characterization of both prototypes and coated kibbles. Results showed consistency in chemical and physical parameters across prototypes despite substantial hydrolysis time variations. However, palatability tests results revealed significant differences in pets’ preference even with slight hydrolysis time changes. The overall trend suggested that a decrease in hydrolysis time could be feasible, especially for dogs’ formulation, while a significant increase in hydrolysis time could negatively affect palatability. Due to occasionally conflicting results, defining an allowable limit for hydrolysis time proved challenging. Therefore, confirmatory tests are recommended to investigate 2h30min as an upper limit for hydrolysis time, while several trials are required to establish a lower limit (range 1h – 1h45min). In conclusion, this project serves as a preliminary study for potential time and cost saving and provides a solid foundation for further investigations. Future research may include a potential scale-up process to meet the company’s strategic goals.