Abstract:
Scallops are rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid but perishable due to their microbial growth and lipid oxidation. In this study, gelatin/dextran films containing cinnamaldehyde and α-tocopherol (0% + 0%, 0.3% + 0.3%, 0.6% + 0.6%, 0.9% + 0.9%, and 1.2% + 1.2%, w/w) as active fillers were developed by solution casting method, and their preservation effects on scallop adductor muscle refrigerated at 4°C for 0, 3, 6, 9, and 12 days were evaluated. Inclusion of the two active fillers did not influence the thermal stability of the films but created heterogenous and discontinuous film microstructure and increased the film hydrophobicity. Increase in the concentrations of active fillers lowered the mechanical properties and water vapor permeability of the films but increased their crystallinity, thickness, water contact angle, opacity, antibacterial property, and antioxidant property. The longest release times for both cinnamaldehyde and α-tocopherol were found in 95% (v/v) ethanol solution. The gelatin/dextran films containing 1.2% (w/w) of active fillers (Gelatin [Ge]/Dextran [Dx]/1.2 film) improved the chemical stability of refrigerated scallop adductor muscle. The total viable count (TVC) of the unpackaged scallop adductor muscle exceeded the recommended limit of 7 lg CFU/g on day 6 (7.07 ± 0.50 lg CFU/g), whereas the TVC of the Ge/Dx/1.2 film-packaged scallop adductor muscle was still below the limit on day 9 (5.60 ± 0.50 lg CFU/g). Thus, the Ge/Dx/1.2 film can extend the shelf life of refrigerated scallop adductor muscle by at least 3 days. Overall, the developed gelatin/dextran active packaging films are promising for the preservation of aquatic food products.
摘要:
扇贝富含二十碳五烯酸(EPA)和二十二碳六烯酸,但由于其微生物生长和脂质氧化而易腐烂。在这项研究中,含有肉桂醛和α-生育酚的明胶/葡聚糖膜(0%+0%,0.3%+0.3%,0.6%+0.6%,0.9%+0.9%,和1.2%+1.2%,w/w)作为活性填料,通过溶液流延法开发,并评价其对4℃冷藏0、3、6、9、12天扇贝内收肌的保存效果。包含两种活性填料不会影响薄膜的热稳定性,但会产生异质和不连续的薄膜微观结构并增加薄膜的疏水性。活性填料浓度的增加降低了薄膜的机械性能和水蒸气渗透性,但增加了它们的结晶度。厚度,水接触角,不透明度,抗菌性能,和抗氧化性能。在95%(v/v)的乙醇溶液中,肉桂醛和α-生育酚的释放时间最长。含有1.2%(w/w)活性填料的明胶/葡聚糖膜(明胶[Ge]/葡聚糖[Dx]/1.2膜)改善了冷藏扇贝内收肌的化学稳定性。在第6天,未包装的扇贝内收肌的总活菌计数(TVC)超过了7lgCFU/g的推荐限值(7.07±0.50lgCFU/g),而Ge/Dx/1.2薄膜包装的扇贝内收肌的TVC在第9天仍低于极限(5.60±0.50lgCFU/g)。因此,Ge/Dx/1.2薄膜可以将冷藏扇贝内收肌的保质期延长至少3天。总的来说,开发的明胶/葡聚糖活性包装膜有望用于水产食品的保鲜。