Monday, January 31, 2011

What's new at The Loft - Episode 76

Macro 3.6.5. Challenge

Doughnut


ISO 1600, f/14.0, 1/4th Second



A doughnut or donut is a type of fried dough food popular in many countries and prepared in various forms as a sweet (or occasionally savory) snack that can be homemade or purchased in bakeries, supermarkets, food stalls, and franchised specialty outlets. They are usually sweet, deep-fried from a flour dough, and shaped in rings or flattened spheres that sometimes contain fillings. Other types of dough such as potato can also be used as well as other batters, and various toppings and flavorings are used for different types.

The two most common types are the toroidal ring doughnut and the filled doughnut, a flattened sphere injected with jam (or jelly), cream, custard, or other sweet fillings. A small spherical piece of dough may be cooked as a doughnut hole. Baked doughnuts are a variation cooked in an oven instead of being deep fried. Doughnut varieties are also divided into cake and risen type doughnuts.


Various doughnut incarnations are popular around the globe. Shapes include rings, balls, and flattened spheres, as well as ear shapes, twists and other forms. Not all doughnuts are sweet: in Southern India for instance, savory doughnuts called vadai are served.


Ring doughnuts are formed by joining the ends of a long, skinny piece of dough into a ring or by using a doughnut cutter, which simultaneously cuts the outside and inside shape, leaving a doughnut-shaped piece of dough and a doughnut hole from dough removed from the center. This smaller piece of dough can be cooked or re-added to the batch to make more doughnuts. A disk-shaped doughnut can also be stretched and pinched into a torus until the center breaks to form a hole. Alternatively, a doughnut depositor can be used to place a circle of liquid dough (batter) directly into the fryer. Doughnuts can be made from a yeast-based dough for raised doughnuts or a special type of cake batter.

After frying, ring doughnuts are often topped with a glaze (icing) or a powder such as cinnamon or sugar. Styles such as fritters and jam doughnuts may be glazed and/or injected with jam or custard.


As well as being fried, doughnuts can be completely baked in an oven.  These have a slightly different texture from the fried variety with a somewhat different taste due to the lack of absorbed oil—and so have a lower fat content. The fried version may sometimes be called "fried cakes".

There are many other specialized doughnut shapes such as old-fashioneds, bars or Long Johns (a rectangular shape), or with the dough twisted around itself before cooking.In the northeast USA, bars and twists are usually referred to as crullers. There are also beignets, which are square donuts topped with powdered sugar.


Doughnuts have a disputed history. One theory suggests that doughnuts were introduced into North America by Dutch settlers, who were responsible for popularizing other American desserts, including cookies, apple and cream pie, and cobbler.[citation needed] Indeed, in the 19th century, doughnuts were sometimes referred to as one kind of olykoek (a Dutch word literally meaning "oil cake"), a "sweetened cake fried in fat."


Hansen Gregory, an American, claimed to have invented the ring-shaped doughnut in 1847 aboard a lime-trading ship when he was only sixteen years old. Gregory was dissatisfied with the greasiness of doughnuts twisted into various shapes and with the raw center of regular doughnuts. He claimed to have punched a hole in the center of dough with the ship's tin pepper box and later taught the technique to his mother.  The first cookbook mentioning doughnuts was an 1803 English volume which included doughnuts in an appendix of American recipes. By the mid-19th century the doughnut looked and tasted like today’s doughnut, and was viewed as a thoroughly American food.


I hope you enjoyed today's yummy picture.  I'd love to hear what your favorite kind of doughnut is so send me a note and let me know.  Thanks for stopping by and come back soon.

Sunday, January 30, 2011

What's new at The Loft - Episode 75

Macro 3.6.5. Challenge

 Soap Bubble


ISO 1600, f/4.0, 1/60th Second


A soap bubble is a very thin film of soapy water that forms a sphere with an iridescent surface. Soap bubbles usually last for only a few seconds before bursting, either on their own or on contact with another object. They are often used for children's enjoyment, but they are also used in artistic performances.

A soap bubble can exist because the surface layer of a liquid (usually water) has a certain surface tension, which causes the layer to behave somewhat like an elastic sheet. Soap film is extremely flexible and can produce waves based on the force exerted. However, a bubble made with a pure liquid alone is not stable and a dissolved surfactant such as soap is needed to stabilize a bubble. A common misconception is that soap increases the water's surface tension, soap actually does the opposite, decreasing it to approximately one third the surface tension of pure water. Soap does not strengthen bubbles, it stabilizes them, via an action known as the Marangoni effect. As the soap film stretches, the surface concentration of soap decreases, which in turn causes the surface tension to increase. Thus soap works by selectively strengthening the weakest parts of the bubble, preventing any one part of the bubble from stretching excessively. In addition, soap reduces evaporation, making the bubbles last longer; but this effect is relatively small.

The spherical shape of a bubble is also due to surface tension. The sphere has the smallest possible surface area for a given volume, thus taking up a spherical shape minimises the free surface of a bubble. This shape can be visibly distorted by air currents. However, if a bubble is left to sink in still air, it remains rather spherical.  
Freezing soap bubbles blown into air that is below a temperature of −15 °C (5 °F) will freeze when they touch a surface. The air inside will gradually diffuse out, causing the bubble to crumble under its own weight.
At temperatures below about −25 °C (−13 °F), bubbles will freeze in the air and may shatter when hitting the ground. When a bubble is blown with warm air, the bubble will freeze to an almost perfect sphere at first, but when the warm air cools, and a reduction in volume occurs, there will be a partial collapse of the bubble. A bubble, created successfully at this low temperature, will always be rather small; it will freeze quickly and will shatter if increased further.

When two bubbles merge, the bubbles will adopt the shape with the smallest possible surface area. Their common wall will bulge into the larger bubble, as smaller bubbles have a higher internal pressure.  If the bubbles are of equal size, the wall will be flat.  At a point where three or more bubbles meet, they sort themselves out so that only three bubble walls meet along a line. Since the surface tension is the same in each of the three surfaces, the three angles between them must be equal to 120°. This is the most efficient choice, again, which is also the reason why the cells of a beehive have the same 120° angle and form hexagons.


17th century Flemish paintings show children blowing bubbles with clay pipes. This means that bubbles as playthings are at least 400 years old. Bubbles can also be effectively used to teach and explore a wide variety of concepts to even young children. Flexibility, color formation, reflective or mirrored surfaces, concave and convex surfaces, transparency, a variety of shapes (circle, square, triangle, sphere, cube, tetrahedron, hexagon), elastic properties, comparative sizing... as well as the more esoteric properties of bubbles listed on this page. Bubbles are useful in teaching concepts starting from 2 years old and into college years. A Swiss university professor, Dr. Natalie Hartzell, has theorized that usage of artificial bubbles for entertainment purposes of young children has shown a positive effect in the region of the child's brain that controls motor skills and is responsible for coordination with children exposed to bubbles at a young age showing measurably better motion skills that those who were not. 


Hope you enjoyed today's picture.  Please send me your comments, I'd love to hear what you have to say.  Thanks for stopping by and come back soon.