Bento is a single-portion takeout or home-packed meal common in Japanese cuisine. A traditional bento consists of rice, fish or meat, and one or more pickled or cooked vegetables, usually in a box-shaped container. Tempura shrimp or vegetables can usually be found in a bento box.
Tempura is a popular element of Japanese cuisine, and consists of battering fish and/or vegetables and deep frying them. Tempura is distinguished from many other battered and deep fried foods by being much lighter and tending to carry less grease. In addition to being served at many restaurants, tempura is available in Japan at roadside stands, where it is often sold in paper cones for consumption while strolling the street. Tempura is also popular in the West, where it is served at many Japanese style restaurants. The light batter has also been adapted for fried foods by some cooks who prefer the more delicate flavor of tempura to conventional heavy batters.
Batter
A light batter is made of cold water,sometimes sparkling water is used to keep the batter light with soft wheat flour. Eggs, baking soda or baking powder, starch, oil, and/or spices may also be added. Tempura batter is traditionally mixed in small batches using chopsticks for only a few seconds, leaving lumps in the mixture that, along with the cold batter temperature, result in the unique fluffy and crisp tempura structure when cooked. The batter is often kept cold by adding ice, or by placing the bowl inside a larger bowl with ice in it. Over-mixing the batter will result in activation of wheat gluten, which causes the flour mixture to become chewy and dough-like when fried. Specially formulated tempura flour is available in worldwide supermarkets. This is generally light (low-gluten) flour and occasionally contains leaveners such as baking powder. Tempura generally does not use breadcrumbs (panko) in the coating. Generally fried foods which are coated with breadcrumbs are considered to be furai, Japanese-invented western-style deep fried foods, such as tonkatsu or ebi furai (Fried prawn).
Frying
Thin slices or strips of vegetables or seafood are dipped in the batter, then briefly deep-fried in hot oil. Vegetable oil or canola oil are most common, however tempura was traditionally cooked using sesame oil. Many specialty shops still use sesame oil or tea seed oil, and it is thought that certain compounds in these oils help to produce light, crispier batter. When cooking shellfish, squid, or hard-skinned watery vegetables such as bell pepper or eggplant, the skin is usually scored with a knife to prevent the ingredients from bursting during cooking, which can cause serious burns from splashing oil. Oil temperature is generally kept between 160 and 180 degrees Celsius, depending on the ingredient. In order to preserve the natural flavour and texture of the ingredients, care is taken not to overcook tempura. Cooking times range between a few seconds for delicate leaf vegetables, to several minutes for thick items or large kaki-age fritters. The bits of batter (known as tenkasu) are scooped out between batches of tempura, so they do not burn and leave a bad flavour in the oil. A small mesh scoop is used for this purpose. Tenkasu are often reserved as ingredients in other dishes or as a topping.