Valentina Panarese

The use of sodium bicarbonate for marination of broiler breast meat

This study aimed to evaluate marination performances and the effect on meat quality traits of sodium bicarbonate, used alone or in combination with sodium chloride, when compared with sodium trypolyphosphate by using advanced analytical tools, including low-field nuclear magnetic resonance and differential scanning calorimetry. In total, 140 samples (cylindrical shape of 1 × 4 cm size) were obtained from a batch of 24-h postmortem broiler breast meat (Ross 708, females, 47 d old). Six of the groups were used for subsequent marination treatments, whereas the last group was kept as a nonmarinated control. Samples were subjected to vacuum tumbling in a special equipped laboratory rotary evaporator with a 12% (wt/wt) water:meat ratio using 6 marinade solutions: 7.7% (wt/wt) NaCl (S); 2.3% (wt/wt) Na(4)O(7)P(2) (P); 2.3% (wt/wt) NaHCO(3) (B); S and P; S and B; S, P, and B. Samples marinated with bicarbonate alone or in combination (B, SB, and SPB) significantly increased (P < 0.05) the meat pH by approximately 0.7 units compared with that of the control, whereas phosphate alone or in combination with salt increased (P < 0.05) the pH by 0.2 units. The combination containing all of the ingredients (SPB) produced the highest marinade performances; however, SB was able to guarantee a better marinade uptake and water retention ability with respect to that of SP. According to low-field nuclear magnetic resonance, the combined use of B and P with S determined a remarkable increase in proportion of entrapped water into the myofibrillar spaces, while the extramyofibrillar water fraction was not modified. Moreover, water gain following marination does not correspond to an increase in the freezable water amount, as detected by differential scanning calorimetry. In conclusion, B is a very promising marinating agent, and it can be exploited to develop processed poultry products with no added phosphates to match the request to avoid the nutritional drawbacks recently indicated with the use of phosphates.

Investigation of the metabolic consequences of impregnating spinach leaves with trehalose and applying a pulsed electric field

The impregnation of leafy vegetables with cryoprotectants using a combination of vacuum impregnation (VI) and pulsed electric fields (PEF) has been proposed by our research group as a method of improving their freezing tolerance and consequently their general quality after thawing. In this study, we have investigated the metabolic consequences of the combination of these unit operations on spinach. The vacuum impregnated spinach leaves showed a drastic decrease in the porosity of the extracellular space. However, at maximum weight gain, randomly located air pockets remained, which may account for oxygen-consuming pathways in the cells being active after VI. The metabolic activity of the impregnated leaves showed a drastic increase that was further enhanced by the application of PEF to the impregnated tissue. Impregnating the leaves with trehalose by VI led to a significant accumulation of trehalose-6-phosphate (T6P), however, this was not further enhanced by PEF. It is suggested that the accumulation of T6P in the leaves may increase metabolic activity, and increase tissue resistance to abiotic stress.