西地那非处方及工艺问题

Manufacture of the product

The manufacture of the sildenafil citrate ODT consists of seven steps: three cycles of blending and milling, two blending steps, compression and packaging. It is a standard manufacturing process and there are no intermediates isolated during the manufacturing process. There are no critical steps, and no in-process controls have been proposed. The process has been adequately validated on three commercial scale batches manufactured at the commercial site. It was demonstrated that the process is capable of producing the finished product of the intended quality.

以上是欧盟评报报告中的工艺表述内容，可否帮忙解答一下：

1、七步工艺是如何划分的；

2、工艺中milling是指什么工艺；

3、处方中含有微晶纤维素、疏水胶体二氧化硅、交联羧甲基纤维素钠，硬脂酸镁，靛蓝胭脂红铝色淀（E132），三氯蔗糖，甘露醇，交联聚维酮，聚乙酸乙烯酯，聚维酮。

调味剂：麦芽糊精，糊精。

天然调味剂：麦芽糊精，甘油（E422），丙二醇（E1520）。

柠檬调味剂：麦芽糊精，α-生育酚（E307）。

按上述工艺描术，如何设计混合工艺比较合理。

4、西地那非较苦，如何通过上述处方及工艺降低苦味。