The correlation among residual nitrites, biogenic amines, N-nitrosamine formation, and degradation occurrence of punicalagin α/ß, rosmarinic acid, carnosol, and carnosic acid in extract-treated sausage during storage.

The aim of this study was to investigate the relation between residual α- and ß-punicalagin in Punica granatum L.; PPE and rosmarinic acid, carnosol, and carnosic acid in Salvia eremophila (SE) with residual nitrites, biogenic amines (cadaverine, putrescine, and histamine), N-nitrosodimethylamine (NDMA), microbial counts, lipid oxidation indices, and color values in extract-treated sausage over 14 days of storage. Sausage containing SE + nitrite 60 ppm (SSN) showed minimum levels of the residual nitrites (13.14 mg/kg), NDMA (0.74 ± 0.05 µg/kg), and biogenic amine (histamine, 1.8 mg/kg; cadaverine, 3.7 mg/kg; and putrescine, 4.3 mg/kg) due to retarded degradation rate of 285.84-216.44 mg/kg; rosmarinic acid, 41.62-33.16 mg/kg; carnosol, and 88.70-76.73 mg/kg; carnosic acid over storage time. The first-order kinetic model fitted well for the degradation of rosmarinic acid and carnosol acid in SSN sample. TBA value remained below the threshold limit (0.32 mg kg-1) through 14 days for SSN. Second-order and zero-order reaction models had the best agreement with sausages' PV and TBA values, respectively. After 2 weeks of storage, E. coli and Cl. perfringens counts in the SN120 (sausage containing 120 ppm nitrite) and SSN were significantly lower than the other samples (p < .05), with the values 2.1 and 1.5 log cfu/g for SN120 and 2.2 and 1.6 log cfu/g for SSN formulation. Conversely, oxidation indices, residual nitrites, NDMA, and biogenic amine increased in sausage samples containing PPE extracts (SPN) owing to total degradation of α- and ß-punicalagin during storage. The results indicated that SE can be used as potential co-preservative by reducing the levels of required nitrite in food industry.

Investigation of cryoprotectants-treated surimi protein deterioration during chilled and frozen storage: Functional properties and kinetic modeling.

The relative cryoprotective effects of flaxseed protein hydrolysate and pectin in comparison with conventional cryoprotectant (sucrose + sorbitol + sodium tripolyphosphates) on stabilization of proteins in surimi of Capoor (Cyprinus carpio) were investigated during freezing (-20°C for 4 months) and chilling storage (4°C for 10 days). Although pectin caused to improve water-holding capacity (27.8%; 4°C and 21.5%; -20°C) on account of highly more inhibitory impact on the ice crystals growth, the protein denaturation may have occurred. It can be related to higher reduction in the amount of salt extractable protein (%) and the immeasurable value of thiol group in surimi formulation containing pectin compared with other cryoprotectants. The results of modeling surimi samples showed that salt extractable protein and sulfhydryl content were in good agreement with the first-order reaction model at -20°C and second-order kinetic model at 4°C. In comparison with other samples, samples treated with flaxseed protein showed the lowest reaction rate constant during chilled and frozen storage. The results confirmed that flaxseed protein with no sweetness and considerable caloric value had a cryoprotective effect similar to sucrose + sorbitol + polyphosphate and even better.

Optimization of Ni(II) adsorption onto Cloisite Na+ clay using response surface methodology.

The aim of this study was to investigate the adsorption of Ni(II) from aqueous solutions onto Cloisite Na+ clay. The effects of the initial concentration of Ni(II), adsorbent dose, pH, and temperature on adsorption capacity were studied using response surface methodology. A second-order regression model was determined based on the experimental results. Analysis of variance used to evaluate the individual and combined effects of process variables showed that initial Ni(II) concentration and adsorbent dose were more significant than solution pH and temperature. Moreover, the interaction effects of the initial concentration of nickel and the adsorbent dose, as well as the solution pH and adsorbent dose were significant. High coefficient of determination (R2 = 0.93) and low probability values signify the validity of the model for predicting the adsorption capacity of Cloisite Na+ for Ni(II) ions. The optimal conditions for pH and adsorbent dose were found to be 6.9 and 0.21 g/L, respectively at a constant temperature of 25 °C and initial Ni(II) concentration of 50 mg/L. Under these conditions, the adsorption capacity of clay was found to be 31.43 mg/g. Moreover, the adsorption isotherms results indicated that these data could be best fitted to the Langmuir isotherm model (R2 = 0.99). The Langmuir maximum adsorption capacity was estimated to be 32.05 mg/g for an adsorbent dose of 0.2 g/L at pH 7 and 25 °C. In conclusion, the results showed that Cloisite Na+ clay can be utilized as an effective adsorbent for the removal of Ni(II) from aqueous solutions.

Bis[(2-amino-phen-yl)methanol-κO,N]bis-(nitrato-κO)manganese(II).

In the title compound, [Mn(NO(3))(2)(C(7)H(9)NO)(2)], the Mn(II) atom (site symmetry 2) is coordinated by two N,O-bidentate (2-amino-phen-yl)methanol ligands and two monodentate nitrate anions in a distorted cis-MnN(2)O(4) octa-hedral coordination geometry. In the crystal, N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds help to establish the packing.