南极磷虾粉真空干燥特性及对其品质的影响

目的 探究南极磷虾粉的真空干燥特性及其营养品质变化规律。方法 将磷虾原料在不同真空度(0.04、0.06、0.08 MPa)及温度(75、85、95 ℃)下进行真空干燥。通过测定干基含水率、干燥速率及水分扩散系数，研究其干燥特性。通过测定虾青素含量、TBA和色差，探究其营养品质的差异。结果 在75 ℃下，采用真空度0.06 MPa和0.08 MPa相较于0.04 MPa，其干燥时间分别缩短了15%、21%。在不同真空干燥条件下，磷虾有效水分扩散系数在(3.555 77~6.574 12)×10⁻¹⁰ m²/s之间，Midilli 模型预测值与实验值之间具有较高的拟合度(R²>0.999)，能较准确地反映虾粉真空干燥过程。提高真空度可显著抑制虾青素的分解及脂肪氧化，在75 ℃条件下，采用真空度0.06 MPa和0.08 MPa相较于0.04 MPa，其虾青素含量分别提高了21%、48%。在95 ℃条件下，采用真空度0.08 MPa相较于0.04 MPa，其TBA值降低了47%。L^*、a^*受到温度的影响更明显，在同一温度下∆E随着真空度的上升而降低。结论 在0.08 MPa、75 ℃下，通过真空干燥可以有效抑制虾粉中活性物质的降解，同时保证干燥速率，此研究为南极磷虾粉的真空干燥工艺设计及生产控制提供了理论参考。

Vacuum Drying Characteristics and Their Effect on Quality of Antarctic Krill Meal

The work aims to investigate the drying characteristics of Antarctic krill meal and the variation of its nutritional quality. The krill raw materials were dried under different vacuum levels (0.04, 0.06 and 0.08 MPa) and temperature (75, 85 and 95 ℃). The drying characteristics were assessed through moisture content (dry base), drying rate, and moisture diffusion coefficient, and the nutritional quality was evaluated by determination of astaxanthin, TBA and colour difference. At the drying temperature of 75 ℃, the drying time at 0.06 MPa and 0.08 MPa was reduced by 15% and 21%, respectively, compared with the vacuum pressure of 0.04 MPa. The effective moisture diffusion coefficients of krill under different vacuum drying conditions ranged from (3.555 77 to 6.574 12)×10−10 m2/s. The Midilli model reflected the vacuum drying process of krill meal accurately, with a good fit between the predicted values and the experimental values (R2>0.999). Increasing the vacuum level significantly inhibited the decomposition and lipid oxidation of astaxanthin. At 75 °C, the astaxanthin content was increased by 21% and 48% at 0.06 MPa and 0.08 MPa, respectively, compared to 0.04 MPa. At 95 °C, the TBA value was reduced by 47% at 0.08 MPa compared to 0.04 MPa. Land avalues were more markedly affected by drying temperature compared to bvalue, and ∆E value decreased with the increased vacuum pressure at the same drying temperature. In conclusion, the vacuum drying at 0.08 MPa and 75 ℃ can effectively reduce the degradation of the active substances in Antarctic krill meal and ensure the drying rate. This study can provide a theoretical reference for the design and production control of vacuum drying process with Antarctic krill meal.