Lorraine Pascal made some macaroons, and added a readymade sugar syrup. Would this be liquid glucose or sugar syrup made earlier and stored. I know how to make sugar syrup, but a ready made one would be much easier when making several flavours.
Lorraine evidently used the Italian meringue method of making macarons. Italian meringue uses hot sugar syrup, not glucose syrup. As you can see from this question, sugar syrup can be kept for a few days in the refrigerator. Simple syrup is available ready made for use in cocktails, but do see William Shakespeare's notes in the commments.