Merlot is often touted as Long Island’s “signature” grape — the varietal and the wine that is going to put the region on the world wine stage. I’m not one hundred percent sold on that notion — some of the Cabernet Franc here is just too good — but the consistency and ripe-ability of Merlot makes it somewhat of a safer choice.  At Le Clos Therese in Aquebogue, owner and winemaker Theresa Dilworth, makes two interesting and decidedly different merlots with good results. These wines, along with her cabernet sauvignon, chardonnay and rose are produced at Premium Wine Group, the…