SCALING/MEASURING • In the foods lab we measure our ingredients mostly by volume (i.e. ml, l) • However, in a bakery or other large scale kitchen operations, ingredients are weighed or scaled. • This is a much more accurate way of determining ingredients.
MIXING AND GLUTEN DEVELOPMENT • GLUTEN – Over the next 2 units, you will need a clear understanding of gluten and the role it plays in baked goods. • Gluten is - a substance made up of proteins present in wheat flour that gives structure and strength to baked goods. • No gluten = no baked goods!
In order for gluten to be developed it must first absorb water (or the like) and then as the dough or batter is mixed or kneaded, the gluten forms long, elastic strands. • As the dough or batter is leavened (pop quiz – what does to leaven mean????), these strands capture the gases in tiny pockets or cells and then the product rises. • When the product is baked, the gluten coagulates or solidifies or (becomes solid) and gives the product strength (able to hold its shape).
Flour is mostly made up of starch but this is not the same as gluten. • Remember, gluten is the protein in flour, not the starch in flour. • If you think of this in terms of everyday proteins and starches, eg. Hamburger v.s the bun, they are definitely NOT the same thing. • So, just as the hamburger wouldn’t be a hamburger without the meat (a.k.a. the protein), a baked good would not be a baked good without the GLUTEN (a.k.a. the protein) • The baked good would simply not hold together.
The Hamburger v.s. the Baked Product • THE BUN = STARCH THE BURGER = PROTEIN OR GLUTEN
When baking, you must be able to control the gluten development or you will wind up with tough, dry cake and tough, hard to chew bread. • When we want a light and tender product like a cake we have to be careful to not overdevelop the gluten and when we want a firm but chewy bread, we need to develop the gluten. One way is by kneading and handling the dough, but again, not so much so that it isn’t edible. • There a few other ways to develop gluten: • Selection of flours • Shortening • Liquid • Mixing method
SELECTION OF FLOURS • Flours can be both weak and strong • Strong flours – have a high protein or gluten content • Weak flours – have a low protein or gluten content • Weak flour is only used for cakes and cookies (i.e. cake flour pastry flour) • Strong flour is primarily used for breads (i.e. bread flour, all-purpose flour) • ** gluten only comes from wheat flour so when using rye, rice or other grain flours the formula must be balanced with some high-gluten wheat flour or the bread will be heavy. • ** people with gluten allergies do have a selection of gluten free products to choose from. They are getting better but in the past gluten free bread was extremely dense and heavy.
Shortening • Any fat used in baking is called a shortening because it shortens the gluten strands • Therefore, fats are tenderizers • a cookie or pastry that is crumbly is said to be “short”, eg. Shortbread cookies • Bread should not be crumbly therefore it has very little fat in it, and cakes and pastries contain a great deal of fat
Liquid • As stated earlier, gluten needs water before it can be developed, therefore the amount of water in a formula can affect toughness or tenderness. • For example, pie crusts are supposed to be very tender so they are made with very little liquid so the gluten isn’t overdeveloped. • The more liquid = the greater the gluten development
Mixing Methods • Generally, the more dough or batter is mixed = the greater the gluten development • MORE MIXING = MORE GLUTEN DEVELOPMENT • MORE GLUTEN DEVELOPMENT = TOUGHNESS • Muffins, cakes, pie crusts – must be tender so they are mixed only a LITTLE • Bread dough must be mixed A LOT to develop the gluten, so they are kneaded for long periods of time • **Bread dough can be overmixed however– so you can’t just mix them forever and ever. Gluten strands stretch only so far and will break if overmixed!!
YEAST Yeast is a microscopic plant and as a living organism, similar to us, it is very sensitive to heat. Yeast is also a leavening agent that uses the process of FERMENTATION. FERMENTATION is the process by which yeast acts on carbohydrates and changes them into carbon dioxide gas and alcohol. This release of gas produces the rising action. The ALCOHOL evaporates completely during and immediately after baking.
Temperatures • Inactive = 1˚C • Best Growth = 20 – 32˚C • Yeast is killed = 60˚C and above
Yeast comes in 3 Forms 1. Fresh Yeast • also called compressed yeast • It is moist and perishable, preferred by prof. bakers • Buy it in 1-lb cakes 2. Active Dry Yeast • Dry, granular • Must be rehydrated 4X its weight in warm water before use 3. Instant Dry Yeast • Also called rapid-rise or quick-rise yeast • Dry, granular • Does not have to be dissolved in water before it is used as it can absorb water much more quickly than regular dry yeast • It also produces more gas than regular dry yeast, so less of it is needed.
FUNCTION OF INGREDIENTS • Flours – to provide structure for your baked products. Nutritionally, it provides starch and some protein. • Fats • To tenderize products • Adds moistness and richness • To increase keeping qualities • To add flavor • Assists in leavening
Types of fats • Shortening - all fats act as a shortening by shortening the gluten strands, however, in this case we mean the white, tasteless fats we use mostly in pastry • Butter or margarine • Nicer flavor than shortening • Melt in your mouth, shortening does not. In fact, after eating icing made with shortening, you can be left with a film of it on your tongue • Oil • Lard – fat of hogs
Sugars • To add sweetness and flavor • To create tenderness and fineness of texture by weakening the gluten structure • To give crust color • To increase keeping qualities by retaining moisture • To act as creaming agents with fats • Food for yeast Chemical name for sugar is sucrose
Liquids • Gluten cannot be developed with out this! • Examples • Too much liquid in a pie crust – the gluten develops and the crust is tough • Too little or no liquid in a pie crust – the gluten doesn’t develop and the pie crust will not hold together. • Types of Liquids: • Water • Milk and cream • Eggs, honey, molasses and even butter sometimes
Eggs • Provide structure • Egg proteins coagulate or solidify to give structure • Emulsification of fats • Egg yolks contain natural emulsifiers which gives a smooth batter • Provide leavening • Beaten egg incorporate air and it expands when baked • Provide shortening action • Egg yolks contain fat so they act like a shortening would • Provide moisture • Give flavor • Add nutritional value • Protein, and vitamins • Change the color
Leavening Agents • Leavening – the production or incorporation of gases in a baked product to increase volume and to produce shape and texture. • EXACT MEASURING IS IMPORTANT BECAUSE EVEN SMALL DIFFERENCES CAN HAVE AN EFFECT ON YOUR BAKED PRODUCT!
Types of Leavening Agents • Yeast • Chemical Leaveners • Baking Soda • Sodium bicarbonate • When moisture and an acid are present, it will release carbon dioxide gas with helps to leaven or make the product rise. • Baking Powder • A mixture of baking soda and an acid • The most versatile because of the above • Just needs moisture to create CO2 gas • 2 types - Single acting – just needs moisture Double acting – require heat as well for the final reaction • Baking Ammonia • Ammonium carbonate • Used when rapid leavening is desired, i.e. cream puffs • Steam • When water turns to steam it expands to 1,600 times its original volume, therefore aiding all baked products containing moisture in rising. • Puff pastry, cream puffs, popovers and pie crusts use steam as their major or only leavening agent and therefore use high baking temperatures to achieve the greatest leavening.
Salt, Flavorings and Spices • Salt • It is more than just a seasoning, or flavor enhancer • It strengthens gluten structure and makes it more stretchable • Inhibits yeast growth, so it can control the fermentation process • Chocolate and Cocoa • Derived from the cacao beans • Cocoa is high in starch and is often considered as part of the flour amount • Spices • Add zing to your final product • Extracts and Emulsions • Extracts are flavorful oils and other substances dissolved in alcohol ex. Vanilla, lemon, almond • Emulsions are flavorful oils mixed with water and emulsions • Can both be natural or artificial