Abstract
In this study, rainbow trout patties (Oncorhynchus mykiss Walbaum, 1792) were treated under a modified atmosphere (MA) (60/40:CO(2)/N(2)) packed with microbial transglutaminase enzyme (MTGase) at varying concentrations (0.5% and 1%) and kept for a full day at 2°C ± 2°C. Denser and more complex intermolecular cross-linking formations between peptides and gel network structures were observed in the first and last scanning electron microscope images of MTGase-containing groups. MTGase increased the springiness, hardness, shear force, and work-of-shear parameters during the storage period in uncooked and cooked patties compared to the control group. The protein, energy, moisture, and amino acid contents were maintained in the MTGase-containing groups, but using MTGase at higher concentrations was ineffective. Microbiological analyses have shown that MTGase is partially effective on microbial fauna, and the most significant inhibitory effect was determined on total mesophilic aerobic bacteria (TMAB). In all groups, the total amounts of saturated, monosaturated, and polyunsaturated fatty acids remained unchanged on both production and expiration days (p > 0.05). After mixing the burger patty additives into the ground meat, the amounts of sodium, calcium, potassium, and magnesium increased in all groups (p < 0.05); however, a decrease in calcium was observed in the MTGase-containing groups (p < 0.05) compared to the control group. The higher proportion of the MTGase-contained group did not exhibit significant differences compared to the lower proportion of the MTGase-contained group, except for textural characteristics and the TMAB inhibition effect.