Q. My mother and I disagree about how to put greasy liquids down the kitchen sink. I think you should run hot water as you do it so the grease will keep moving. She thinks you should run cold water. Who wins?A. I hate to end this year by being the bearer of bad news, but the truth is, neither of you win.I, too, have been guilty of putting grease down the drain (especially since living in the “city” where I can’t just go dump the grease behind the barn like when I was kid). And I’ve always assumed hot water would be the way to go, seeing as it should keep the grease moving.But when I consulted Graber’s Plumbing here in Newton, the answer wasn’t “hot” or “cold,” but rather “don’t ever put grease down a drain.”I was informed that even if you use hot water, the grease still will coagulate when it hits the cold pipes, and solid grease doesn’t make for happy pipes.(Isn’t coagulate an awesome word? I don’t get to use that one every day.)The gentleman I spoke with at Graber’s mentioned the city probably wouldn’t be too fond of lots of grease down the pipes, and Suzanne Loomis, city director of public works, confirmed that yes, it’s quite true the city wants to avoid grease going down drains. Loomis said grease can cause a blockage in individual service lines or in the public main. Not fun.In fact, a little online research shows a wealth of information and persuasive arguments against putting grease down the drain or using garbage disposals to cut up fatty foods. One city even has a 30-second YouTube video encouraging you to “can” the fat (dispose of grease, drippings and the like in a closed coffee can or similar container).I also stumbled across a short video with a helpful hint — keep a large plastic jug with a lid (like a large oil jug) under your kitchen sink. Put any grease left in the pan in the jug. When it’s full, take it to a full-service recycling center for disposal (www.howcast-.com/videos/273558-Dont-Pour-Kitchen-Grease-Down-the-Drain).As one site put it, “If you like to dump your leftover food scraps, oils and grease down the drain, chances are you’ll pay for it sooner or later.”And on that cautionary note, I bid you a Happy New Year. See you in 2010!