I'm not sure if the term "pasta glass" was used in Murano, or if it is a term used by collectors.
It refers to opaque glass that is not cased under clear. If you look closely, you'll see that almost all Murano glass is cased inside a clear layer - sometimes this layer is extremely thin, but it's what makes the glass shiny. With pasta glass, the glass takes on a dull look that resembles cooke, dry spaghetti, hence the name. I think you see it best in the picture of Javier's figurine, as with my vase, only the blue bands are pasta - the white portions are cased in clear.
Usually you see this technique in circa 1920s and 30s items.