Bakery Ingredients – Making better bread
Consumers are now enjoying several varieties of bread. This presents bakers with a chance to design and optimise innovative formulae that improve the quality and nutritional profile of bread, at the same time ensuring its shelf life, ease of processing and consistent final product specifications. Bread must contain somewhat established proportions of basic ingredients like flour, fat, leavening, sugar and water. It is a challenge to add new ingredients for functional and nutritional improvements. Even the slightest variation in ingredient quantity or manufacturing process can make changes in the final baked item.
While exact and consistent ingredient measure is the first step to prepare quality bread, small changes in ingredients quantities and specs can have detrimental effect unless adjusted.
Pick a bag of flour
Flours can vary e.g. regular wheat (all-purpose) flour contains only endosperm portion of grain. Wholegrain includes germ and bran as well, which contain fibre, oil and vitamins. Wholegrain is thus more nutritious but bran and germ may affect the bread-making qualities like ability to be leavened by yeast. Gluten expands to accommodate gas produced by yeast and baking coagulates the gluten giving bread its structure and strength. Rye is capable of forming gluten but compared to wheat gluten, rye gluten is inferior and weak. Barley also contains some gluten, so these other grains must be combined with wheat flour to compensate for their low gluten in order to make yeast-leavened products from other flours.
Gluten content is very important to bread makers. Ingredients quantities and manufacturing processes are decided by how they affect gluten development and hence the bread structure. When dough is kneaded gluten develops but beyond a point gluten is overstretched and loses elasticity. The aim is to develop highly elastic dough with maximum retention of gas giving more loaf volume and fineness of texture.
Very strong flours are important in commercial baking operations using high-speed machines kneading for a very short time. The unbleached, unbromated and enriched flour has 12.25 per cent protein and produces strong dough allowing various additions like tomato bits, sunflower seeds, raisins etc. Even different shapes can also be easily formed.
Addition of Enzymes
Enzymes are very important for the bakery industry as without it no baking can happen.In commercial baking applications, enzyme addition helps maintain consistency when protein levels and mix times change. With stronger flours, more mix times are needed and production may come down. Enzyme cuts down the problems and loss in production. Enzyme action contributes to dough relaxing, preventing dough shrink-back, better bread volume and pan flow and faster bakery throughput. Another action of enzyme is useful in debittering and helping in browning and forming of bread flavour. Amylases, proteases, hemicellulases, cellulases, xylanases, glucose oxydase, catalase etc. are predominantly used for baking application.
The shortening of it
Commercially baked bread usually contains fat ingredients either solid or liquid, to improve crumb softness, volume and texture. The fat is typically referred to as shortening because it shortens or breaks up masses of gluten thus weakening the structure and making final bread more tender. While mixing, fat surrounds the gluten particles and lubricates them so that they do not stick together. Fat acts as a tenderizer. Bread dough does not require much tenderisation as cake batter, so bread formulas generally do not use them but cake formulations use them regularly.
Another important function of fat in bread is to slow moisture loss by coating starch granules increasing the shelf life by delaying stalling. The final load volume also increases by up to 20 per cent when 3.4-5 per cent shortening is used. The increase in volume is higher than the melting point of fat. Solid fats like vegetable shortenings and butter have been favourites in bread formulae, but hydrogenated vegetable fats used as shortenings are high in trans and saturated fatty acids, both with negative health implications with respect to heart diseases.
Bakers are now searching for alternatives as shortening in bread. USDA’s Agri Research. Service (ARS) has identified oat oil that could make bread more healthy. It is also rich in phospholipids and glycolipids and so oil combines with water to lubricate bread dough to help it rise evenly and bake a loaf that is uniformly springy and soft even after several days. The polar lipids like in this oil also help in making bread with hard red winter-wheat flour. The ARS has bread a new waxy durum wheat that could replace vegetable shortening without losing desired properties conferred by shortening. This wheat has almost 100% amylopection in starch whereas normal wheat contains 76%, the remainder being amylose. It works as a shortening when it comprises 20% of dough formulation.
Another oil has been developed that is mostly composed of diglycerides and made from soya and canola oil. This has same properties but much of it is metabolized as energy instead of being stored as fat. One more oil has been developed from short and long chain fatty acids for bread applications. This has lower calories (5 kcal compared to 9 kcal from normal fat).
Getting into condition
Small bakeshop bakers have more hands-on control in bread making process than big commercial operations where bakers rely on adding ingredients to ensure proper bread-structure and shelf life. The ingredient that is always used is dough conditioner to improve yeast dough performance during processing and baking to produce softer crumb and ease in slicing with fewer crumbs.
Many different ingredients are used for conditioning that cause interaction with gluten and starch in the flour. There is no single conditioner applicable everywhere. Specially formulated dough strengthener and crumb softener is especially effective in wholegrain and high-fibre speciality breads. It allows dough to withstand harsh mechanical handling in automated process.
Traditionally, potassium bromate was used. This oxidising agent was an ideal conditioner due to its slow release. A significant amount remained in dough and was available at the proofing and baking stages to provide good oven spring. Ascorbic acid can replace bromate but it requires encapsulation, otherwise it reacts too early in the mixing stage. Technological advancements like encapsulation and dough conditioners ensures that ingredients are available at the proper time for their action. Too early release of conditioners may result in dough that is too tight too early and the mixing time increases. Lipid encapsulated dough conditioners are to release at the end of proofing, right before baking or right at the start of baking.
The “en” crowd
Encapsulation also enables adding preservatives that reduce mould growth without affecting yeast action as they also inhibit yeast fermentation. Hence these should not be released into the dough until after the fermentation process is over. Encapsulated sorbic acid and calcium propionates released when high temperatures are reached during baking.
Enzymes can also extend the shelf life and are increasingly used in bread. They are used in low levels (at 0.2%) and can have great impact on the finished bread. High heat stable bacterial alpha amylase extends the shelf life from 4 to 9 days. Blends of different enzymes have given shelf life up to 30 days. These enzymes break down gelatinized starch into simple sugars, creating moisture inside the bread. This helps keep bread soft and fresh-feeling. As little as 0.12% concentrated enzymatic dough conditioner and softener produces bread with whiter crumb, finer grain and texture. This extends shelf life by keeping crumb soft.
Encapsulation is also useful in adding certain flavours and nutrients. To reduce fermentation time and prepare bread with sourdough flavour profiles replace traditional sourdough cultures with encapsulated sourdough flavours. Without encapsulation these flavours will affect yeast as they are acids. Encapsulation releases the flavour at the right time during baking, after fermentation is over for natural sourdough flavour profile.
Principal flavour component in cinnamon, cinnamic aldehyde (added to non-sandwuich bread with raisins and other dry fruits) inhibits microbes including yeast inhibiting its action during proofing causing under-leavening and lower volume. Therefore, bakers refrain from adding cinnamon to dough and apply iot in the form of topical crumble or sprinkle. Increasing yeast levels can counter this but is expensive and affects sensory properties. Microencapsulation is a solution wherein encapsulated cinnamon ingredient gives the flavour without affecting volume.
Fitting fibre in
Consumers are aware of the benefits of high fibre diet such as reduced risk of heart disease, hypertension, cancer, diabetes and obesity. Switching from white to whole-wheat and other wholegrain baked products is healthy boosting dietary fibre intake but needs technology to make it more palatable. ARS scientists used ultra-fine ground whole wheat flour to make bread more palatable with taste and texture very similar to white bread. Whole grain is not the solution to increase fibre. Speciality fibre ingredients can be added with minimal or no effect on the properties of the final product. Certain speciality resistant starch with clean, neutral taste and white in appearance allows incorporation into all types of breads. While fibre ingredients change the bread’s texture, resistant starch improves it and also boosts the fibre content. High level of resistant starch can be added to bread formulations with some adjustment of water may be needed along with possible addition of gluten.
Boosting nutritional profiles
US bakers are somewhat limited in nutrients that could be added to breads as the term “enriched” is standardized by the FDA. However, other ingredients like fruits, nuts and seeds may be added to boost the nutritional profile. Enriched bread contains 1.8mg thiamine, 1.1mg riboflavin, 15mg niacin, 12.5mg iron and 0.43mg folic acid per pound. Further the law allows 600mg of calcium. Most premixes are custom blended for bakers. As other added ingredients can contribute to nutrient profile, premix might need more or less of certain nutrients, depending on the desired final nutrient profile. Premix, commonly encapsulated to withstand extreme temperatures encountered during baking, is added to the formula dry ingredients.
Fruits like raisins contribute to iron, thiamine, magnesium, potassium, copper and fibre. Rauisins contain 5.3 % fibre, more than half being soluble. It has several other properties and help ensure shelf life. Another ingredient with goof nutrients is flaxseed. The seed is shiny, reddish brown in colour, with crisp and chewy texture having a nutty flavour profile. It has 42% oil low in saturated and extremely high in omega-3 fatty acid, a-linoleic, that is useful for the retina and brain development in infants and reduces the risk of cancer, hypertension and cardiovascular diseases. Flax seed has 28% fibre, both soluble and insoluble. The soluble fibre is associated with lowering blood cholesterol and insoluble fibre prevents constipation.
Bakers can use these ingredients at different levels to create variety and at the same time ensuring machineability and quality, and consistency of the finished product.
Extracted from an article by Donna Berry in Food Product Design