fold [fohld] verb

A common technique of combining mixtures (usually two) in a delicate manner. Folding is often employed when you want to retain air that has been beaten into egg whites or whipped cream, as when making soufflés or mousses. To combine, the aerated mixture is gently laid on top of the heavier mixture then the baker passes a rubber spatula through the layers across the bottom and “folds” the mixture up over the top until both are fully combined.  Recipes direct you to fold to keep the air bubbles in the mixture for a soft and light finished product. It is very distinct from stirring or beating.

Bakepedia Tips

Excessively rapid or heavy-handed folding will take air out of your mixture instead of retaining or adding it, so a light, gentle-but-quick rhythm will enable effective folding. We often begin this process (especially large amounts) with a balloon whisk, which naturally helps retain air in the mixture, and then finish with a rubber spatula.

firm ball stage [furm  bawl steyj] noun

A phrase referring to a stage of cooked sugar, when a drop of sugar syrup placed in cold water will form a firm but pliable ball, which can be assessed between the fingertips.  More specifically, the ball will not flatten when you take it out of the water; it will remain malleable but will flatten when squeezed firmly.

On a candy thermometer, the firm ball stage is between 244° and 248° Fahrenheit. This stage is used in many confectionary recipes, such as caramels.

Bakepedia Tips

Any time you are working with hot sugar, be sure to have a bowl of ice water at hand, as spilled hot sugar can burn severely. In the event that you get hot sugar on your skin, immerse it quickly in the iced water to literally lower the temperature of your skin.

fermentation  [fur-men-tey-shuh n] noun

A process in which yeast and bacteria convert carbohydrates, such as sugar, to alcohol and carbon dioxide. Fermentation is used to produce alcoholic beverages such as wine, beer and cider, and is also responsible for leavening bread and preserving sour foods such as sauerkraut, yogurt and vinegar. It results from the addition of yeast, or – as is the case with sourdough starters – without any added yeast.

The sharp, earthy taste of sourdough bread comes from its starter, which is usually just flour and water.  The fermentation happens naturally with yeast and bacterium (lactobacillus) that is already present in the flour and grows over time as the starter is fed. Some starters have been in existence for many decades.

Bakepedia Tips

Many welcome the distinct taste of sourdough, but creating and taking care of a starter requires some attention. If the starter is not fed regularly, it will stop growing (which means the fermentation has ceased) and become unusable.  Most starters need to be fed about twice a day when they are created, and even if the starter is not being created from scratch, they still need to be fed once a week. People with starters literally have to have them babysat when they go away on vacation!