Introduction

Significant amounts of evidence have shown the health benefits of docosahexaenoic acid (DHA) in humans and animals. Dried microalgae Schizochytrium sp. is a sustainable and commercially available ingredient with a high concentration of bioavailable DHA.

Objectives

The objective of this study was to measure the stability of DHA in a wet pet food during retort and storage.

Methods

The dried microalgae Schizochytrium sp. (DHAgoldTM S17-B, DSM Nutritional Products, Columbia, MD, USA) was added at 2.3% in a typical loaf type of wet pet food. It was mixed with chicken, chicken liver, chicken broth, brown rice, flaxseed, sweet potatoes, powdered cellulose, choline chloride, salt, potassium chloride, taurine, cassia gum, carrageenan, guar gum, vitamins and minerals in a mixer for 4 minutes and heated to 43°C before filling the mixture in standard steel cans (156 g). The cans were sealed, retorted at 122°C for 60 minutes, and cooled to room temperature before they were stored at 32°C for 12 months and ambient temperature (21°C) for 24 months. Samples were taken at various time points during the storage for DHA measurements with a GC method.

Results

No noticeable loss of DHA was observed during the pet food process and retort. DHA retention was 66% at 12 months and 87% at 24 months under the storage conditions at 32°C and ambient temperature, respectively.

Conclusions

In conclusion, DHA in DHAgold S17-B is stable in wet pet food during retort and long-term storage.