Yeasts for Baking. Generally when one mentions yeast, aromatic loaves of fresh homemade light bread come to mind. And so they should. Aside from acting as a leavening agent in bakery products, yeast is also the ingredient responsible for the tantalizing aroma that arises during baking.
Though probably today the most commonly known and used are store-bought packages of dried yeast, there are several other different kinds. The recipes that follow show two examples of different ways to make yeast--dry yeast cakes made from hops and an everlasting yeast "starter"--and also how the yeasts are used in making bread.
The dry yeast cakes are made in part by boiling the blossoms of the hop vine. These flowers contain a fragrant yellowish oil called lupulin. The use of this oil as a preservative in beer and as a narcotic drug originated in Germany before Charlemagne. Since then its use has become widespread and the vine cultivated in other nations, including America.
Solar energy, radiant light and heat from the sun, has been harnessed by humans since ancient times using a range of ever-evolving technologies. Solar radiation, along with secondary solar-powered resources such as wind and wave power, hydroelectricity and biomass, account for most of the available renewable energy on earth. Only a minuscule fraction of the available solar energy is used.
Solar technologies are broadly characterized as either passive solar or active solar depending on the way they capture, convert and distribute solar energy. Active solar techniques include the use of photovoltaic panels and solar thermal collectors to harness the energy. Passive solar techniques include orienting a building to the Sun, selecting materials with favorable thermal mass or light dispersing properties, and designing spaces that naturally circulate air.