Background Squid is a highly nutritious food, rich in protein, iron, calcium, phosphorus, and other trace elements. Due to its excellent quality, great taste, and widespread popularity among consumers. Squid can be processed in various ways. However, current research on squid processing primarily focuses on individual methods. The quality and flavor variations of squid resulting from different processing techniques require further in-depth investigation. Additionally, it is essential to elucidate how the unique flavors associated with these processing methods are formed.

Objective The present study aims to reveal the effects of different thermal processing conditions on the flavour quality of squid slices, provide a reference for the thermal processing quality control technology of other aquatic products, and open up new ways for the safe processing of high-protein and low-fat aquatic products.

Methods Illex argentinus was used as the main research object, and the squid was processed in three ways: boiling, air frying and oven baking, and the traditional boiled and thermally processed squid (SS) was used as the control to investigate the effects of air frying (FS) and oven baking (OS) on the color difference value, texture (hardness, elasticity and chewing), electronic nose (e-nose) and gas chromatography-mass spectrometry (GC-MS), as well as other physicochemical indices.

Contents Boiled squid group (SS) was used as a control to evaluate the effects of air frying (FS) and oven baking (OS) on the physicochemical indices such as color difference value, texture (hardness, elasticity and chewiness), e-nose and GC-MS of squid.

Results Oven baking and air frying technology could effectively enhance the colour saturation and uniformity of squid slices, giving them better visual appeal. In terms of textural analysis, squid slices from FS and OS groups were significantly better than those from SS group in terms of hardness, elasticity and chewiness. The analysis of volatile compounds revealed a total of 39 volatile compounds detected across the three groups of squid slices, with the OS group exhibiting the highest abundance. Notably, the generation of 4, 5-dimethylthiazole was unique to the FS and OS groups. Additionally, both 2, 3-butanedione and 4, 5-dimethylthiazole in the OS group had an odour activity value (OAV) greater than 1, indicating their significant contribution to the overall flavour of the squid. The cumulative contribution of the e-nose reached 87.37%, and the main volatile odour components of the three groups of squid slices included inorganic sulphides, aromatic components (organic sulphides) and nitrogen oxides. The lateral relaxation time of squid slices less susceptible to flowing water and free water was reduced and the squid slices tissues were more compact after heat treatment by air frying and oven baking.

Conclusion Compared with the traditional boiling method, the baking treatment with air frying and oven baking can significantly improve the quality characteristics of squid slices, give the squid slices better texture, colour and lustre, and endow the squid slices with richer organoleptic qualities.