No abstract

The modified atmosphere packages (MAP) was used to preserve the fresh noodles and the effect of atmosphere ratio (N 2 : CO 2 = 0:100, 20:80, 30:70, 40:60 or 50:50) on noodle quality was investigated with normal packages as control. The results showed that the MAP could significantly extend the shelf life of fresh noodles up to at least 7 d, compared with the control. On the 7th day of storage, the elasticity and hardness gradually decreased with the increase of N 2 : CO 2 ratio (P > 0.05) even if the MAP group were poor than the control (P > 0.05). In terms of water content, on the 7th day of storage, the decrease of 0:100 group and 20:80 group was less than that of control group (P < 0.05), and the effect of water retention was better. On the 7th day of storage, pH in the MAP group decreased less than that in the control group (P < 0.05). During the same storage period, the inhibition effect of the 0:100 group was significantly higher than that of the control group (P < 0.05), while the L* values decreased less in the 0:100 and 30:70 groups than in the control group (P < 0.05).

High density polyethylene (HDPE) and nano-ZnO were used to prepare nano-ZnO/HDPE composite film with a nano-ZnO content of 0.5wt%. The morphology, mechanical, barrier and antibacterial properties, as well as the preservation to cheese of the films were studied. The results showed that the ZnO nanoparticles had a good dispersion in HDPE matrix so that the improvement of the mechanical, barrier and antibacterial performances of the film was achieved after the addition of nano-ZnO to HDPE. In comparison to cheese packaged in HDPE bags, it was found that the sensory score of the cheese in nano-ZnO/HDPE bags increased from 66.6 to 73.7 and the pH of cheese was closer to the standard sample at storage time of 7d. Furthermore, nano-ZnO/HDPE inhibited effectively the increase of the total bacterial count (TBC) on cheese contrast of HDPE. That indicates the prepared nano-ZnO/HDPE is potential in cheese packaging to extend the shelf life.

In this study, we prepared new antioxidant active plastic bottle caps by incorporating butylated hydroxyanisole (BHA) or butylated hydroxytoluene (BHT) and 2% (w/w) white masterbatch in high-density polyethylene (HDPE). Fourier-transform infrared (FT-IR) spectrometry revealed that the antioxidants and HDPE were uniformly mixed with noncovalent bonding. In addition, the differential scanning calorimetry (DSC) test revealed that the change in melting point and initial extrapolation temperature of the antioxidant active caps was not significant. Sensory evaluation and removal torque tests validated the suitability of the antioxidant active plastic bottle caps in industrial application. The antioxidant activity increased with a greater concentration of BHA and BHT incorporated in both antioxidant active caps (p < 0.05) and with more impact on the BHA cap compared to BHT cap in terms of antioxidant activity. Migration experiments for 10 days at 40 °C and 2 h at 70 °C showed that active antioxidants in the plastic bottle cap were more easily released into fatty foods and milk products that are highly sensitive to oxidation, and the migration of BHA and BHT did not exceed the maximum amount specified in (EC) No 1333/2008 (<200 mg/kg). As such, the antioxidant active plastic bottle caps inhibited oxidation, thereby ensuring higher food quality.