Focus on product and process
Which chemical leavener a baker chooses is driven by the finished baked food and the process.
“Higher or lower batter temperatures, shorter or longer process times, low- and high-moisture products, refrigerated doughs, frozen doughs, extruded snacks — all of these require manipulation of the gas release,” Ms. Thomas explained.
Gas release will be affected by the type of leavening acid and particle size of the sodium bicarbonate, so bakers will need to select the proper combination of acid and base to deliver the right amount of release at the right time during manufacturing.
A chemical leavening reaction can be triggered by heat or liquid, and that can be a fast or slow reaction. It all depends on the final product and the process it will endure.
“Leavening acids exist that are fast-acting, time-delayed or heat-triggered, with many choices in each category,” Dr. Book explained. “The selection of leavening acid will impact cell size and grain, tenderness, volume and even color.”
Bakers must consider temperature and time throughout the process when looking at chemical leavening ingredients. Gas reactions are directly impacted by batter and dough temperatures. Cooler temperatures will slow down gassing, while warmer temperatures will speed up gassing rates.
“If a tortilla dough becomes too warm during mixing, there will be too much gas produced during mixing and processing and not enough during the baking stage, with the outcome being a translucent, thin and leathery tortilla,” Mr. Bright said.
The proper chemical leavening system also will heavily depend on time spent on the production floor. Cake muffins baked right away vs. those produced from a frozen batter have very different leavening needs. Even a characteristic like the top of a muffin will be impacted by leavening, Mr. Olds explained.
“If you want a flat-top muffin, you may choose to use different components than you would if you were creating a dome-top muffin,” he said. “Depending on when the leavening occurs, you could get two very different outcomes.”
Some products require a delayed rate of reaction. For these applications, Innophos offers a wide range of sodium acid pyrophosphate (SAPP) in a variety of different reaction times. Depending on a baker’s needs, the company can offer a SAPP reaction that is slow or fast.
When it comes to the product’s final quality, chemical leavening, like all ingredients, will have an impact on many different parameters, including taste, texture, volume and shelf life. For formulas containing chocolate or cocoa powder, for example, Mr. Shaheed said bakers will want to choose chemical leavening agents that enhance the brown color and not lighten it, which some leavening acids can do.
For low-volume, low-moisture products such as cookies, Dr. Book suggested monocalcium phosphate monohydrate (MCP) to provide the bubbles necessary for rise. To get more volume in products that need it, she suggested additional acids like SAPP or calcium acid pyrophosphate (CAPP). Doughs that will sit for an extended period before baking will need what the heat-activated reaction sodium aluminum phosphate (SALP) brings to the formula.
And in today’s consumer climate, bakers can’t afford to forget how ingredients appear on the label. Bakers going for organic will be limited to very specific certified organic chemical leavening ingredients. Those going for a clean label will be only restricted by what their consumers consider “clean.” Another parameter involves sodium reduction. Commonly used chemical leavening agents are a source of sodium in baked foods. One way to reduce it is to use leavening ingredients outside of the sodium box.
For organic baked foods, bakers can use MCP, dicalcium phosphate dihydrate (DCP) and SAPP.
“Organic is clearly defined,” Dr. Book said. “Clean label is not defined, so it’s more in the attitude of the company and how they and their consumers interpret what clean label is.”
Baking powders have been around for more than 150 years and are common in most household pantries. However, sodium bicarbonate, common baking soda, might sound foreign to those same consumers. Dr. Book would argue those ingredients, because they are found in the domestic kitchen, would be clean label.
“One succinct definition of clean label is foods already in the grocery store, say buttermilk, orange juice or vinegar, which are all sources of acids,” she explained.
These acidic foods can provide some leavening reactivity, but it can be difficult to control, whereas more conventional leavening acids can provide bakers with more control over their final products.
This article is an excerpt from the February 2019 issue of Baking & Snack. To read the entire feature on chemical leavening, click here.