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An HPLC method coupled with pre-column derivatization was used to analyze the concentrations of six biogenic amines (BAs) including putrescine, cadaverine, histamine, spermidine, tyramine and spermine in Gonatopsis borealis(a species of squid) during different storage conditions (0 °C and 4 °C, 0–12 d; 25 °C, 0–24 h). Results showed that histamine (21.03–32.26 mg/kg) was the dominant BA in squid muscle stored at refrigerator temperature, followed by spermine (10.84–7.94 mg/kg) and spermidine (3.67–11.20 mg/kg). The levels of six BAs in the squid muscle increased with storage time, and their formations during storage were zero-order reactions (0 °C, R2= 0.834–0.979, k= 0.0003–0.0006 mg/kg min−1; 4 °C, R2= 0.705–0.994, k= 0.0004–0.0006 mg/kg min−1; 25 °C, R2= 0.454–0.931, k= 0.0003–0.0512 mg/kg min−1), which meant that the contents of BAs in squid muscle did not affect their formation rates. In addition, the concentrations of BAs were correlated with total volatile base nitrogen (TVB-N) values (R2= 0.604–0.966). The results of multivariate linear regression analysis show that the use of six BAs could predict the TVB-N value in squid muscle very well (R2= 0.944–1.000). This study revealed the changes and formation kinetics of six BAs in Gonatopsis borealisstored at refrigerator and ambient temperature conditions, which could contribute to improving the safety and quality of shellfish products.

Dietary advanced glycation endproducts (AGEs), such as Nε-carboxymethyllysine (CML) and Nε-carboxyethyllysine (CEL), may promote aging and increase the risk for development of various chronic diseases. The effects of beef fat (8.3− 32.4 %), sodium nitrite (50 − 150 mg/kg) and sodium erythorbate (100 − 1000 mg/kg) contents on the formation of free and protein-bound AGEs including CML and CEL in ground beef during heating (100 °C, 0 − 60 min) were investigated. The proportion of free AGEs accounted for 1.1− 8.7 % of the sum of free and protein-bound AGEs, and decreased as the severity of the heat treatments increased. The amounts of free CML and CEL formed in ground beef (based upon protein weight) during heating were not affected by the levels of beef fat or sodium nitrite, but slightly decreased with the addition of 100 − 400 mg/kg erythorbate. The formation of protein-bound CML and CEL during heating was promoted with the addition of beef fat and erythorbate, but inhibited by nitrite. The overall effects of fat, nitrite and erythorbate on AGEs formation were relatively small compared to that of heat treatments. This study provides a greater understanding of the compositional factors involved in the formation of AGEs in complex foods during heating, which may help the optimization of thermal processes so that lower levels of AGEs are formed during food production operation.