The inclusion of new ingredients in fish feed can affect the physical quality of the pellets. In order to study the effect of the addition of microalgae on the physical properties of the pellets, 15 extruded diets were studied that included three different species of microalgae (Nannochloropsis gaditana, Tetraselmis chuii and Chlorella vulgaris) at five different inclusion levels (0, 2.5, 5, 10 and 15%). The feed mixtures were extruded using a single-screw extruder (barrel temperature profile: 90–95–100 °C; die temperature: 105 °C; screw speed: 40–50 rpm). The physical properties studied included: expansion ratio, density, hardness, pellet durability index, water absorption index, water solubility index, floatability, sinking velocity, fat leakage and starch gelatinization. The present study showed that the physical properties of the pellets are influenced by the type and amount of microalgae used. The physical quality of the feed was modified, generally increasing its hardness and durability and reducing the fat leakage.

鱼饲料中包含新成分会影响颗粒的物理质量。为了研究微藻添加对颗粒物理性能的影响，研究了15种挤压饲料，其中包括三种不同的微藻（Nannochloropsis gaditana，Tetraselmis chuii和Chlorella vulgaris）。）分为五个不同的包含级别（0％，2.5％，5％，10％和15％）。使用单螺杆挤出机（料筒温度曲线：90–95–100°C；模头温度：105°C；螺杆速度：40–50 rpm）挤出进料混合物。研究的物理性能包括：膨胀率，密度，硬度，颗粒耐久性指数，吸水率，水溶性指数，浮性，下沉速度，脂肪渗漏和淀粉糊化。本研究表明，颗粒的物理性能受所用微藻的类型和数量的影响。修改了饲料的物理质量，通常可以提高其硬度和耐用性，并减少脂肪泄漏。