Lipid-involved browning mechanism during the drying process of squid

The present study evaluated lipid-involved browning mechanism during the drying process of squid. Initially, different lipid-Maillard reaction (MR) models were conducted based on the composition of squid (lipids, reducing sugars and amino acids). The degree of MR as well as α-dicarbonyl compounds (α-DCs) and lipid oxidation-mediated browning products (pyrroles and lipofuscin-like pigments) were detected. The results indicated that arginine and ribose were blamed for the browning of dried squid. Moreover, lipid oxidation provided glyoxal and methylglyoxal to participate in MR, and long-time heating and salting produced more α-DCs and accelerated browning. Meanwhile, dried squid contained hydrophilic pyrrole (17.45 μg/g lipid) and hydrophobic pyrrole (113.00 μg/g lipid), and the content of lipofuscin-like pigments increased by 1.5-fold after drying. Finally, defatting treatment demonstrated that the browning of dried squid was moderately alleviated by fat removal (L* ↑, a* ↓ and b* ↓). These findings offer a novel perspective on moderately preventing the browning of dried aquatic products.