Rising to the Top
Among numerous subjects, the baked goods and snacks sessions featured enzyme choice and dough conditioner systems.--Eds.
Traditional Baking Enzymes--ProteasesDiscussing various proteases used in the baking industry, Peter Moodie, director of sales and marketing, Enzyme Development Corporation, described the rationale for using proteases, the physical properties of each enzyme and typical applications.
Proteases hydrolyze proteins into simpler compounds such as peptides and amino acids. Enzymes exert two basic types of action on proteins--endo and exo. Endo action splits the polymer randomly anywhere along its chain, which contributes to dough relaxation, prevents shrink-back and improves bread volume and gas retention. In addition, endo action increases bakery throughput. Exo action cleaves a specific terminal group, such as an amino acid or a di- or tri-peptide, on the protein polymer. Free-amino acids contribute to browning and may reduce bitter peptides, thereby modifying flavor.
Proteases are derived from animal, botanical and microbial sources, although animal proteases such as pancreatin, trypsin and chymotrypsin are rarely used in baking because of the expense involved and their non-kosher status. Botanical sources include papain, bromelain and ficin, none of which have amylase or pentosanase activity. Of these, bromelain and papain are used most frequently. The most common sources of fungal proteases are Aspergillus oryzae and Aspergillus niger, which are neutral to acid pH applications, relatively slow-acting, and may have significant amylase and pentosanase-side activity. Other common sources of microbial proteases are Bacillus subtilis and licheniformis, which are used in neutral to mildly alkaline applications and may have significant amylase.
In a baked good, enzyme choice depends on the enzyme's ability to control the rate of reaction. As a rule of thumb, fungal proteases are the slowest; bacterial proteases react at moderate speed, and bromelain is the fastest. Proteases are used in breads, crackers, cookies, tortillas and pizzas. In traditional sponge-dough breads, for instance, protease can be added directly to the sponge side or the dough side. In a straight dough, protease improves handling properties, resulting in a mellower, less bulky dough. Better pan flow and improved gas retention are achieved in a no-time dough. In continuous-mix systems and extruded doughs, proteases improve dough handling with less wear and tear on the machine.
Dough Conditioner Systems in Baked GoodsManufacturers of baked goods face greater demands to meet new trends and control costs. Improved softness, extended shelflife, processing ease and anti-stick properties are common basic requirements. The type of flour used by the baker to produce this variety of baked goods can vary greatly with respect to its grind, its physical shape, the way it is refined or separated from unwanted components of the grain and its protein content.
Over the years, the protein content of typical bread flour used by wholesale bakers has dropped from 12.5% to 12.75%, as was common in the 1950s, to 10.8% to 11.5%--levels often seen today. As the protein level of bread flour decreased, the ash content increased. By today's standards, flour with the same protein content and a higher ash content may not have as good a baking quality as a similar flour with a lower ash content. Bakers' methods of coping with fluctuating flour quality was addressed by Susan Gurkin, global application manager, Degussa Food Ingredients, Texturant Systems.
New developments in bread ingredient technology provide bakers with dough conditioners that make the flour perform better--as if it has higher protein content. To improve bakery product quality, many minor functional ingredients are used, including hydrocolloids, emulsifiers, enzymes, oxidizing agents and/or reducing agents. These minor ingredients often are formulated into “improver” and “conditioner” blends. Dough conditioners provide optimum characteristics in bakery products such as improved volume, softness, machinability, crumb structure and freeze/thaw stability, as well as reduced staling. More importantly, these functional systems improve the adaptability to changing production methods and ingredient variability.
The term dough conditioner is used not only for ingredients that truly condition the dough (i.e., improve dough processing characteristics for better finished product quality) but also for combinations of ingredients. Base ingredients in the dough conditioner category include: yeast foods such as ammonium sulfate and ammonium chloride; oxidizing agents like ascorbic acid, potassium bromate and azodicarbinamide (ADA); drying agents such as calcium peroxide; and reducing agents like L-cysteine. Enzymes, emulsifiers and hydrocolloids also are used to impart significant effects on product quality. Advantages of dough conditioner blends include ease of use; productivity improvement, due to fewer raw materials stocked and weighed into a batch; and improved product consistency, due to fewer minor “weighings.” This lessens the chance of inaccurate dosing and reduction of finished product quality due to raw material variation.