Paprika extract as a natural antioxidant in cold-stored pork patties: Effect on oxidative stability and heterocyclic amines inhibition

In this study, we compared the degree of oxidation of pork patties refrigerated at 7 °C for 0, 7, and 14 days and the content of 10 types of heterocyclic amines (HCAs) after heating. The pork patties used in the study were added with 0.7 mg sodium nitrite (SN) and 5 mg paprika extract (PE), respectively. IQx (2-Amino-3-methyl-imidazo[4,5-f]-quinoxaline), MeIQx (2-Amino-3, 8-dimethyl-imidazo[4,5-f]-quinoxaline), PhIP (2-Amino-1-methyl-6-phenyl-imidazo[4,5-b]-pyridine), and Harman (1-Methyl-9H-pyrido[4,3-b]-indole) contents increased with increasing storage periods of treatment. On the other hand, HCAs production in SN and PE treatments were suppressed over the storage period, with IQ (2-Amino-3-methyl-imidazo[4,5-f]-quinoline) and Aαc (2-Amino-9H-dipyrido[2,3-b]-indole) being suppressed significantly (P < 0.05). The control's pH, cooking loss, lipid, and protein oxidation were higher than SN and PE-treated patties at 14 d (P < 0.05). These differences affect the formation of HCAs. PLS-DA showed a strong correlation between protein oxidation and IQx, Harman, 4,8-DiMelQx (2-Amino-3, 4, 8-trimethyl-imidazo[4,5-f]-quinoxaline), PhIP, and MeIQx, while lipid oxidation correlated with IQx, Harman, and PhIP. Both SN and PE showed HCAs inhibitory activity and exhibited oxidative stability during storage.

Effects of volatile organic compounds of smoke from different woods on the heterocyclic amine formation and quality changes in pork patty

This study investigated the effects of smoke derived from cypress (CY), mulberry (MU), metasequoia (ME), pine (PI), and camphor (CA) on the heterocyclic aromatic amines (HAs), flavor, and sensory attributes of smoked pork patty. The results showed that the smoke derived from the five kinds of wood and the flavor of the corresponding smoked meat were classified into three types. Moreover, the smoke of CY and PI, and the smoke of MU and ME can be classified into one category respectively, which significantly improved the flavor of the smoked meat. Both free and protein-bound HAs were detected in smoked meat, while the smoking process significantly increased the HAs content, especially free Norharman (3.26 ng/g in control meat, and 82.24 ng/g in meat smoked with CY). Correlation analysis showed that various volatile organic compounds (VOCs) and HAs were closely associated. Future research should pay attention to the VOCs in smoked meat including vanillin, Close attention should be paid to tridecane and crotonic acid, as well as tetradecane and α-Dehydro-ar-himachalene in smoke, which were consistently correlated with various HAs and may participate in HAs formation. These results may reveal how the smoking process influences the formation of HAs and which factors should be targeted to inhibit HAs in smoked meat products.

Effect of freeze-thaw cycles on the quality of quick-frozen pork patty with different fat content by consumer assessment and instrument-based detection

The change in quality of quick-frozen patties containing different amounts of added fat (0%, 5%, 10%, 15%, and 20%) under different freeze-thaw (F-T) cycles (a F-T cycle was performed by freezing at -18 °C and thawing at 4 °C) was evaluated. The results showed that the a*-values of samples were significantly decreased, while L*-values, b*-values, thawing loss, and cooking loss were notably increased after 3 F-T cycles. Low-field nuclear magnetic resonance (LF-NMR) results showed that the water mobility of patties was enhanced. Textural properties (hardness, springiness, cohesiveness, and chewiness) of patties were significantly decreased after 5 F-T cycles (P < 0.05). Lipid and protein oxidation were aggravated with increasing fat content and number of F-T cycles, as confirmed by the increase in lipid peroxides, TBARS, and carbonyl content. Therefore, the results from instrument-based detection and consumer scores indicated that repeated F-T cycles accelerated the quality deterioration of quick-frozen pork patties, and rendered them unacceptable after 3 F-T cycles.