[1 - 1] botanically speaking sweet potatoes are
[1 - 5] part of the conv let's the conv let's
[5 - 9] yeah kind of a convoluted combo that
[9 - 13] this family they're part of this family
[13 - 18] boy this is give me a tough one sweet
[18 - 20] potato is one of most important food
[20 - 21] crops in the world 90 percent of
[21 - 23] production happens in Asia where most
[23 - 25] people Tate OHS are white-fleshed though
[25 - 27] some are purple and they vary in levels
[27 - 29] of sweetness and starchiness if you can
[29 - 30] get your hands on Japanese white sweet
[30 - 32] potatoes do it when roasted they are
[32 - 35] rich sweet and chestnut II YUM
[35 - 36] here in the states it's easiest to find
[36 - 38] one of three kinds of sweet potatoes and
[38 - 40] they're all orange fleshed and
[40 - 41] definitively sweet and they have
[41 - 43] incredible names we've got the
[43 - 46] Beauregard the jewel and the red garnet
[46 - 48] sweet potatoes sound fancy and I guess
[48 - 50] when it comes to the science behind them
[50 - 52] but kind of our fancy so let's do some
[52 - 54] fancy science when we talk about fresh
[54 - 55] produce for pre-much always trying to
[55 - 57] limit storage time after harvest to
[57 - 59] avoid spoilage or just bad things
[59 - 61] happening to the food we want fresh food
[61 - 62] and rightfully so but with sweet
[63 - 64] potatoes I actually want them to be old
[64 - 66] well maybe not old old because we've all
[66 - 68] seen sweet potatoes sprout right you
[68 - 69] haven't seen that oh my god they throw
[69 - 71] out these beautiful shoots and leaves
[71 - 73] take a look sorry getting off track we
[73 - 74] don't want super old sweet potatoes but
[74 - 76] we want ones that have been stored in a
[76 - 77] cool dark environment for a certain
[77 - 79] period of time before they end up at the
[79 - 81] supermarket why because sweet potatoes
[81 - 84] in storage are changing in a really cool
[84 - 86] way sweet potatoes contains special
[86 - 87] enzymes called amylases that break down
[87 - 90] starch into sugars because I was born in
[90 - 91] the 80s I like to think of the enzyme as
[91 - 93] a big pac-man chomping down on long
[93 - 95] chains of starch and spitting out tiny
[95 - 97] little sugars but now that's how you're
[97 - 98] gonna think of it too
[98 - 100] sorry so how much of an impact is
[100 - 102] storage have on sweet potatoes well up
[102 - 104] to 27 percent of the starch and sweet
[104 - 105] potato can be converted to sugars in a
[105 - 107] period of 10 weeks that's significant
[107 - 109] but doesn't have to stop there
[109 - 111] those enzymes work faster and faster as
[111 - 112] the temperature increases all up to the
[112 - 115] point at which they die enzymes are so
[115 - 117] dramatic in the 140 to 170 degrees
[117 - 119] fahrenheit range these enzymes are
[119 - 121] working overtime during cooking
[121 - 123] emily's --is can convert as much as 75%
[123 - 125] of the starch in the sweet potato to
[126 - 128] sugars you could take advantage of this fancy
[128 - 130] you could take advantage of this fancy science and a couple of really cool ways
[130 - 132] let's go to the kitchen exhibit a
[132 - 135] roasted sweet potatoes place coins of
[135 - 136] seasoned sweet potatoes on a baking
[136 - 138] sheet cover with foil placed into a cold
[138 - 140] oven and then turn on the heat that
[140 - 141] gradual climb in temperature slowed
[141 - 143] further by the wrapped baking sheet
[143 - 145] means that the sweet potatoes spend a
[145 - 146] lot of time in that literal sweet spot
[146 - 148] you get less starchy slightly sweeter
[148 - 149] sweet potatoes but with lovely
[149 - 152] caramelized exteriors Exhibit B sweet
[152 - 154] potato soup to make a smooth not too
[154 - 156] thick sweet potato soup you normally
[156 - 158] have to add a lot of liquid to thin out
[158 - 159] all of that starch and all of that extra
[159 - 162] liquid means less sweet potato flavor if
[162 - 163] only there was a way to cut back on some
[163 - 165] of that starch I don't know converts
[165 - 168] some of it to sugar guys there is that's
[168 - 169] what we've been talking about we just
[169 - 170] bring our cooking liquid up to a simmer
[170 - 172] remove the pot from the heat and drop in
[172 - 174] our cut-up sweet potatoes let them hang
[174 - 175] out and they're warm little enzyme bath
[175 - 177] for about 20 minutes and just check out
[177 - 179] the difference this is a batch where we
[179 - 181] use that step and this is a batch where
[181 - 182] we didn't crazy right
[182 - 184] roasted sweet potatoes sweet potato soup
[184 - 186] even sweet potato casserole all great
[186 - 187] dishes but none of them holds the title
[187 - 190] of best sweet potato dish because that
[190 - 193] title belongs to sweet potato fries and
[193 - 195] the only thing better than how awesome
[195 - 197] sweet potato fries are to eat is how
[197 - 199] easy they are to make you just slice
[199 - 201] them up like this and cook them in 325
[201 - 202] degree oil like this until they're crisp
[202 - 204] on the outside and creamy on the inside
[204 - 206] then hit them with a little bit of salt
[206 - 209] and mmm-mmm-mmm
[209 - 212] these are mmm these are I'm enjoying
[212 - 214] these these are really these are really
[214 - 218] yummy I recommend eating these okay so I
[218 - 219] have to be honest with you well you just
[219 - 221] saw me doing there was acting didn't
[221 - 223] actually enjoy those fries at all but I
[223 - 225] was acting as if I did as much as I wish
[225 - 226] it was that easy to make sweet potato
[226 - 229] fries it just isn't it's challenging to
[229 - 230] make good sweet potato fries for the
[230 - 231] exact same reasons that I've just been
[231 - 233] gushing about sugar and a conversion of
[233 - 235] starch to sugar a high sugar content
[235 - 237] does not lend itself well to fried foods
[237 - 240] starch is what hydrates and crisps when
[240 - 242] we fry food and sugars just brown burn
[242 - 244] and get in the way so with sweet
[244 - 246] potatoes it's easy to end up with fries
[246 - 248] that are golden brown even dark even
[248 - 250] burned and still sod
[250 - 251] it's a total bar but if you're thinking
[251 - 253] yourself I get good sweet potato fries
[253 - 255] at restaurants all the time what's the
[255 - 257] deal the deal is that those fries are
[257 - 259] enrolled in a starchy coating the
[259 - 260] starchy coating gets crisp the inside
[260 - 262] turns sweet and creamy and everybody's
[263 - 264] happy the good news is we can do this at home
[264 - 267] the good news is we can do this at home too and we can do it better we're gonna
[267 - 269] make thick cut super crispy sweet potato
[269 - 271] fries cuz I love that contrast of crisp
[271 - 273] exterior and lots of creamy interior so
[273 - 275] we'll cut nice thick wedges out of these
[275 - 277] Beauregard sweet potatoes we already saw
[277 - 279] what happens when we straight-up fry
[279 - 280] these so we're not doing that instead
[280 - 282] we're gonna boil them for a couple of
[282 - 283] minutes and water the despite the salt
[283 - 285] and baking soda you'll see that after
[285 - 287] just a few minutes the exterior of these
[287 - 289] potatoes has turned bushy which looks
[289 - 292] pretty gross right wrong this is exactly
[292 - 293] what we want to have happen the baking
[293 - 295] soda raises the pH of the water which
[295 - 297] speeds the breakdown of pectin only at
[297 - 299] the surface so these are mushy on the
[299 - 301] outside but still undercooked inside now
[301 - 302] we just transfer these guys while
[302 - 304] they're still nice and hot to this bowl
[304 - 305] where I've whisked together water and
[305 - 308] cornstarch and we fold and fold and fold
[308 - 310] and fold a couple of things are
[310 - 312] happening here first the cornstarch is
[312 - 313] gelling thanks to the heat from the
[313 - 315] sweet potatoes and second that mushy
[315 - 316] exterior is coming off and mixing with
[316 - 318] that cornstarch batter turning
[318 - 320] everything a lovely orange color trust
[321 - 323] lovely and boom now we have sweet potato
[324 - 325] wedges that are still pure sweet potato
[325 - 326] on the inside but they're coated in a
[326 - 328] higher starch sweet potato mixture on
[328 - 330] the outside you thinking what I'm
[330 - 332] thinking yeah it's time to fry we're
[332 - 333] gonna use a nice cast-iron skillet here
[333 - 336] to give more space to each wedge and cut
[336 - 339] down on sticking oh my god look at these
[339 - 341] beauties actually know what forget about
[341 - 347] that listen to these beauties
[350 - 350] look I'm kidding I don't I don't mean
[350 - 352] this celery Thank You God yourself it's
[352 - 355] not your episode just listen to the
[355 - 357] sweet potato fries they are crisp
[357 - 358] crunchy on the outside
[358 - 360] sweet dense and creamy inside and
[360 - 362] perfect for dipping in spicy mayonnaise
[362 - 364] I love them roasted a love mint soup I
[364 - 366] love them twice baked but at the end of
[366 - 368] the day there's really no debate this is
[368 - 371] how to eat sweet potatoes
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