The food lab better home cooking through science ( PDFDrive ) 885

WHY WON’T MY MAC ’N’ CHEESE REHEAT? M ac ’n’ cheese is notoriously bad for reheating Rather than a smooth, creamy sauce, you end up with a grainy, curdled, broken, unappetizing mess It’s all the pasta’s fault As we know, creating a stable cheese sauce requires the careful balance of fat to moisture, along with some emulsifying agents to help keep that fat and water getting along nicely together Even though the pasta is completely cooked when it goes into the sauce, it has such a loose, sponge-like structure that it can continue to absorb water as it sits overnight in the refrigerator This throws off the balance of the sauce, and the result is a sauce with too much fat that breaks out when you reheat it So is there a solution? Yes: just add back the water, duh I’ve found that the best thing to do is add a few tablespoons of milk, which is essentially water with a bit of fat and a few proteins and sugars mixed in The water content of the milk fixes the ratio, while the proteins help ensure that the sauce gets reemulsified, as long as you stir while you reheat Your pasta will always be mushier than it was in the first place, but sometimes mushy pasta can be a good thing CHEESE CHART T he meltability of various cheeses can be affected by a number of factors, including their manufacture and their chemical makeup, but the most important thing is age Young, moist cheeses tend to melt a whole lot better than older, drier ones But what exactly happens when cheese melts? Most cheeses are made by adding bacteria and rennet § to milk The bacteria consume sugars, producing acidic byproducts Aside from lending tang and flavor, these acids, along with the rennet, cause the proteins in the milk (mainly casein) to denature Imagine each protein as a tiny spool of wire that gets slowly unwound The more it unwinds, the easier it is for it to get itself tangled up with other bits of wire This is exactly what happens in cheese The kinked wire– like proteins tangle up with each other, forming a stable matrix and giving the cheese structure Trapped within this matrix are microscopic bits of solid fat and water As cheese is heated, the first part to go is the fat, which begins melting at around 90°F Ever notice how a piece of cheese left out in the heat for too long forms tiny beads on its surface? Those are beads of milk fat Continue to heat the cheese, and eventually enough of its protein bonds will break that it’ll flow ... to milk The bacteria consume sugars, producing acidic byproducts Aside from lending tang and flavor, these acids, along with the rennet, cause the proteins in the milk (mainly casein) to denature... unwound The more it unwinds, the easier it is for it to get itself tangled up with other bits of wire This is exactly what happens in cheese The kinked wire– like proteins tangle up with each other,... by a number of factors, including their manufacture and their chemical makeup, but the most important thing is age Young, moist cheeses tend to melt a whole lot better than older, drier ones But