There are no instructions that are attached to potatoes when you buy them at the store. The way most people know about how to cook them is because their mother told them and they just obeyed. She never gave you a reason why, but you never questioned why and did it her way.
I always was curious about ‘why’ and ‘how come’ and when I asked her questions she would always say, “Because I told you so!”
Well, thank goodness for Harold McGee for explaining the ‘why’ and ‘how come,’ that a simple vegetable like a potato is actually very complex and is difficult to cook.
“Starchy Vegetables: Potatoes, sweet potato, winter squashes, and other starchy vegetables owe their distinctive cooked texture to their starch granules. In the raw vegetables, starch granules are hard, closely packed, microscopic agglomerations of starch molecules, and give a chalky feeling when chewed out of the cells. They begin to soften at about the same temperature at which the membrane proteins denature, the “gelation range,” which in the potato is from 137 to 150 degrees F (it varies from plant to plant). In this range the starch granules begin to absorb water molecules, which disrupt their compact structure, and the granules swell up to many times their original size, forming a soft get, or sponge-like network of long chains holding water in the pockets between chains. The overall result is a tender but somewhat dry texture, because the tissue moisture has been soaked up into the starch. (Think of the textural difference between cooked high-starch potatoes and low-starch carrots.) In starchy vegetables with relatively weak cell walls, the gel-filled cells may be cohesive enough to pull away from each other as separate little particles, giving a mealy impression. This water absorption and the large surface area of separate cells are the reasons that mashed potatoes and other cooked starchy purees benefit from and accommodate large amounts of lubricating fat.”
Potatoes need to be boiled starting from cold water to raise the temperature only gradually to reinforce their cell walls. Do not add salt as it would encourage early softening of the exterior.
I boil potatoes almost everyday for macaroni-potato and purple sweet potato salads. For macaroni-potato salad, I use waxy, salad potatoes. You do not want to overcook them so I time them for 15 minutes after I get a rapid boil, turn off the heat and let them sit in the water for 15 minutes, then check the potatoes by poking them to be sure they are cooked through. This assures me that I will have potatoes that are cooked through and are not mushy and falling apart.
Scalloped potatoes are not difficult to make but if your recipe has sour cream, the potatoes may not soften. Also choosing the right type of potato matters. Choose waxy, thin-skinned potatoes because they have a lower starch content with higher water content. Using a mandoline to slice the potatoes super thin to allow them to cook evenly and give a nice potato to sauce ratio. Using a knife may lead to slices that are too thick. Milk will curdle if the heat is too high, which makes the proteins in the milk bind together, causing lumps. Use gentle heat, about 325 degrees, to avoid curdling. If your recipe calls for garlic, cook them slightly first. The acid in raw garlic could also cause curdling of the milk. Another factor is the more cream in the milk, the less likely it will curdle. The milk also must be very fresh.
Cook only until the potatoes are tender. If you overcook the potatoes, the milk is more likely to curdle and the potatoes will break down into mush.
The casserole needs to rest to allow the potatoes to hold together better and ensure every scoop will be saucy instead of having the sauce fall to the bottom of the dish.
French fries need to be fried in cool oil (250 degrees) for 8-10 minutes first, then at 350 degrees for 3-4 minutes to brown them.
There are over 200 varieties of potatoes and the three basic types are the starchy types, waxy and all-purpose ones
Starchy potatoes are high in starch, low in moisture and have a floury textures with creamy white flesh. Russets and sweet potatoes fall into this category. These are best for crispy potatoes, potato chips, mashed potatoes and French fries. They are not recommended for casseroles, gratins or potato salads.
Waxy potatoes has less starch and more moisture and sugar. They are often smaller with waxy outer skin and creamy, firm and moist flesh. These are your red salad and gold salad potatoes and are the best for potato salads.
All-purpose potatoes are in between starchy and waxy potatoes and have more moisture than starchy potatoes and hold together in boiling water. New potatoes and Yukon gold are in this category and work well in soups or gratins.
Foodie Bites
Hawaii Community College’s Culinary Program’s Cafeteria and Da ‘Ohana Corner Cafe is open Tuesday-Thursday from 10:30 a.m.-12:30 p.m. for pick up. Call 808-934-2559 for The Cafeteria and 808-934-2591 for Da’Ohana Corner Cafe.
Email Audrey Wilson at audrey wilson808@gmail.com.