The wonders of the freezer as a meals preservation instrument are apparent, however the freezer can do extra than simply retailer meals. It can be used as a kitchen instrument. A few of these strategies have already been written about on Critical Eats. There are cryo-shelling of clams and different shells; cryo-bleaching vegetables and herbs like basil; tender octopus; and curing spongy pork fat to facilitate slicing.
Nonetheless, there are different prospects. For those who have been to seek the advice of the Chinese language House Cooking Guide, you’ll uncover a bunch of strategies that use the freezer to rework meals textures and improve flavors in ways in which would in any other case be tough to attain.
Many of those strategies predate the usage of trendy freezers. In northeast China, it was frequent to retailer fruits, greens and different substances outdoors the house throughout the winter, uncovered to sub-zero snowy temperatures. A few of the substances can be stored there all through the season after which eaten throughout the hotter months, however others can be cooked and eaten throughout the chilly season. And when these substances have been introduced again in and thawed, they have been markedly totally different, essentially altered. As an example how the freezing course of can change substances and to get concepts on how you can make the most of these modifications to supply scrumptious dishes, let’s take a look at the particular examples beneath, every accompanied by a recipe.
Frozen Roasted Candy Potatoes
My favourite utility of this concept can be one of many easiest. Through the winter, in lots of East Asian cities, together with Hong Kong, the place I grew up, you will discover roasted candy potato distributors parked on road corners. At one finish of a small cart is a large wok full of pebbles, heated with charcoal. The seller regularly throws the pebbles into the wok with candy potatoes to supply fantastically caramelized wok-roasted candy potatoes with shiny, chewy flesh and a skinny, papery, toasty pores and skin. In cities with colder climates, distributors are in a position to constantly obtain that cloud-like texture by first freezing entire candy potatoes earlier than they’re roasted, or permitting them to freeze naturally on the cart. at sub-zero ambient temperatures or, in at the least a couple of circumstances that I do know of in Hong Kong, by intentionally inserting them in a freezer.
Because the candy potato freezes, the water contained in the candy potato varieties ice crystals, which have sharp, jagged edges that puncture the cell partitions of the flesh, altering the feel potato in order that when roasted, it comes out extra tender and fluffy. Primarily based on different assessments of this method by Tim Chin (spoiler: he found that this method of frozen roasting produces by far the most delicious sweet potatoes), there may be an additional benefit to the freezing step. By reducing the beginning temperature of the potato after which roasting it whereas nonetheless frozen, the potato spends much more time in a really particular temperature zone between 135°F and 170°F (57°C to 76°C), the temperature vary by which a pure potato enzyme known as amylase begins to work additional time to transform complicated starches into candy maltose sugar. It is one thing Kenji takes benefit of in his roasted sweet potato and mashed sweet potato recipes too.
The result’s a fantastically roasted candy potato with deep sweetness and a texture paying homage to candy potato pie. It is fantastic eaten out of the blue, however I’ve additionally concocted a easy however tasty presentation by which the roasted frozen sweet potato is topped with light and tangy fresh whipped cream and sprinkled with granola.
I’ve discovered that this method works greatest on sweeter candy potato varieties, corresponding to purple-fleshed candy potatoes or Carolina ruby yams, the place the naturally excessive moisture content material exaggerates the impact of freezing. Alternatively, roasting frozen white-fleshed Okinawa candy potatoes (and common Russet potatoes) is not as environment friendly.
Fruit poached in ice cream (“cryo-macerated”)
Northeastern Chinese language delicacies is deeply rooted in native farming practices, together with freezing fruit in winter. An instance is Asian pears that are repeatedly frozen and thawed till the as soon as tan skins flip black and the insides soften and burst with juice.
The normal technique to eat the pear is to pierce the pores and skin of the fruit along with your tooth and suck out the pure syrup, after which you’ll eat the fruit in bigger bites. The method of freezing and thawing transforms the pear, picked when arduous and bitter, right into a delicacy in its personal proper. It nonetheless retains its uncooked pear taste and nearly extremely recent style, however its texture is mushy, with a slight crunch, as if it had been expertly poached.
What goes into the pear is just like what goes into the candy potato, however after all the pears aren’t cooked afterwards. Nonetheless, repeated freezing and thawing causes giant, slowly forming ice crystals to interrupt down the cell partitions of the fruit flesh, releasing taste compounds and sugars. The method additionally damages the pores and skin, inflicting it to oxidize (and due to this fact flip black), however the pores and skin stays intact, and I’ve discovered that it naturally protects the fruit flesh from freezer burn, permitting pears to go away within the freezer for a number of months with out sequelae. To borrow a time period from winemaking that describes freezing the grapes earlier than fermentation to weaken the skins and extract extra tannin and taste, the pear is successfully “cryo-macerated”.
The approach used for cryo-macerated or ice-poached pears is used for different fruits in northeast China. Persimmons, peaches, and cherries all undergo the same course of to create snacks that are actually eaten year-round. And the approach has many purposes, like in my extra elaborate recipe for ice-poached pears: it is a version of “poached” pears served with a light syrup, in this case flavored with Chinese medicinal ingredients like goji berries, apricot kernels and osmanthus.
To broaden this concept outdoors of conventional Chinese language delicacies, one can think about freezing fruits corresponding to apples, plums and apricots to restart the method of extracting sweetness and taste, with out having to prepare dinner them, to uncooked jams, jellies, cobblers or desserts.
Extremely-Absorbent Glazed Tofu
In a savory context, frozen tofu is a well-liked instance of fixing the feel of an ingredient by freezing it. Frozen tofu takes on a yellow tint and extra porous texture, which not solely provides tofu a chewy texture and meat-like bounce, but in addition a sponge-like high quality that permits it to soak up liquids and to present extra taste to every chew. The impact is achieved, as soon as once more, with the assistance of ice crystals, which broaden as they kind, tearing aside the clotted protein construction of the tofu. When the tofu thaws, water leaks by this internet of lacerations, leaving tiny air pockets in all places.
To boost this impact, it’s best to softly squeeze the thawed tofu between your arms, squeezing out much more water and rising the absorption potential of the tofu whereas concentrating the flavour of the tofu itself.
Frozen tofu is eaten most frequently in casseroles, braises, soups and casseroles the place the spongy texture can take up cooking liquid. Even within the easiest liquids, as in my recipe for glazed tofu simmered with Napa cabbage, pork and a little ginger and garlicthe tofu will get juicy and substantial in a means that recent tofu simply will not.
These are just some examples of how freezers can be utilized to control each the feel and taste of meals. When contemplating different makes use of of the freezer in the same means, it’s helpful to bear in mind two (associated) results of freezing on substances – softening and lack of moisture – to find out whether or not utilizing the freezer may be a good suggestion.
When contemplating softening, ask your self if there are any advantages to getting a looser, extra tender, and doubtlessly extra spongy texture. Root greens like beets and taro, for instance, may benefit from the softening results of the freezer, as that is the last word texture we’re normally on the lookout for. However leafy greens, cabbage, or Brussels sprouts, however, would change into mushy and unattractive for a stir-fry by which you need the greens to retain some crunch.
As for moisture loss, that is an unavoidable impact of freezing most substances, because of all that cell harm brought on by the ice crystals. Whereas it really works splendidly with candy potatoes, pears, tofu, and so forth., it may be an issue with substances like meat, the place you wish to retain as a lot moisture as potential. When unsure, keep in mind that there’s little hurt in experimenting. You could come upon an entire new technique to put together and luxuriate in considered one of your favourite meals.