一般来说，大部分剩菜都没有刚出炉的味道好。但是许多人也有过这样的体验：有些剩饭剩菜第二天吃起来好像更加美味？比如像咖喱、披萨和一些荤菜等。

这是什么原因呢？费城莫内尔化学感官中心的帕梅拉·道尔顿博士对此进行了解释。

图源：iStock

食物从烤箱或锅中取出后，味道并不会停止变化。

As for the food, just because you take something out of the oven or off the stove doesn't mean the flavors of that dish stop evolving.

人们通常感觉剩菜的调料味道更香醇。以咖喱为例，即使你在当天烹饪得很好，它的味道仍然会在口中有些强烈，但是第二天吃，就更加融合，不会那么强烈了。

One of the main differences people cite with leftovers is a mellowing of spices. Taking curries as an example, when you taste it that very day, even though you cook it well, it still feels a bit harsh on the palate. But when you have it the next day, it sort of blends and matures and is not so strong.

图源：视觉中国

另外，汤汁或酱汁中配料的味道也会转移到食物上，类似于腌制的过程。

There's also a transference of flavor that can happen with ingredients suspended in a liquid or sauce, similar to the process of marinating.

marinate /ˈmærɪneɪt/ 腌制，腌渍，浸泡（食物）

许多香料的味道分子随着时间的推移能够寻找到菜肴中的脂肪，导致味道分子更容易为我们的感官所接受。

脂肪可以传递香气，让我们的味蕾感觉到本来可能会忽略的味道。

这些浸满香气的油脂覆盖着舌头，使各种芳香化合物能够长时间接触我们的味蕾，加强和延长我们对各种味道的体验。

One thing that happens is the flavor molecules of many spices are able to seek out the fats in a dish over time, which results in the flavor molecules being more accessible to our senses. Fat can convey aromas — and enhance flavors — to our palates that would otherwise go unnoticed. Fat coats the tongue, allowing various aromatic compounds to stay in contact with our taste buds for longer periods of time, intensifying and prolonging our experience of various flavors.

aroma /əˈroʊmə/ 芳香，浓香；（喻）气氛

图源：视觉中国

当这些现象同时发生时，饭菜的味道就会更加和谐。

此外，剩菜的味道组成也可能发生变化——变得更甜，苦味减少或者鲜味增加。

The composition of leftovers' tastes can also shift — becoming sweeter, decreasing in bitterness or developing more umami.

umami /uːˈmɑːmi/ （食物的）鲜味

“糖可以进一步分解并从食物中释放出来，”道尔顿说。“特别是，淀粉类食物会释放出更多的葡萄糖和蔗糖。”这种额外的甜味可能对香料和酸度有抑制作用。

"Sugars can break down further and be released from foods," Dalton said. "Particularly, starchy foods will liberate more glucose and sucrose." This additional sweetness can have the potentially adverse effect of dampening spice and acidity. 

glucose /ˈɡluːkoʊs/ 葡萄糖；葡糖

sucrose /ˈsuːkroʊs/ 蔗糖

dampen /ˈdæmpən/ 使潮湿，弄湿；减弱，抑制

图源：视觉中国

虽然像苹果、土豆等食材的氧化会影响口感，但对于含硫量高的农产品，如葱和十字花科蔬菜，暴露在氧气中会使它们变得不那么苦。

Oxidation is primarily associated with the browning of cut apples or potatoes, but it can affect flavor, too. With produce high in sulfur, such as alliums and cruciferous vegetables, exposure to oxygen will help them to become less bitter over time.

sulfur /ˈsʌlfər/ 硫，硫磺；硫磺色；

alliums /ˈæliəm/ [植] 葱属植物

cruciferous /kˈruːsɪfərəs/ 十字花科的

肉类由于蛋白质会继续分解而变得更软，因为蛋白质分解会释放出可以增强菜肴鲜味的氨基酸。

When it comes to meat, the proteins in meats will break down more and it'll become softer. As a result of this breakdown, amino acids are released that can enhance the umami of a dish.

amino acids 氨基酸

以上原因，就解释了为什么一些菜留到第二顿反而更好吃。

实习生：刘柏林

来源：华盛顿邮报