Gelatin–Tea Tree Essential Oil Coating Improves the Quality, Flavor, and Micromolecular Metabolites of Squid (Illex argentinus) Muscle During Cold Storage

Squid muscle is delicious and nutritious, but it is highly susceptible to spoilage, severely limiting its market development. This study comprehensively evaluated the effects of gelatin (Gel), essential oil (Ess), and Gel + Ess coating on the quality, flavor, and microorganisms of squid muscle during refrigerated storage (4 °C). The results showed that squid muscle treated with Gel + Ess exhibited higher water-holding capacity and sensory evaluation, but lower pH value, chromaticity, and texture parameters than those treated with sterile water (control) during cold storage. The total volatile basic nitrogen (TVB-N) result demonstrated that the shelf life of squid muscle treated with Gel + Ess coating was extended to 12 days at 4 °C, longer than the control group. The Gel + Ess group had the best inhibitory effect on aldehydes and ketones in refrigerated squid muscle, and it could effectively maintain the flavor quality. In addition, the Gel + Ess coating showed an additive inhibition on the growth of Cockerella and Shiwanella compared to the individual compounds. The Gel + Ess coating is a novel strategy for improving the quality, flavor, and micromolecular metabolites of squid muscle during cold storage.