Sodium Reduction in the Baking Industry - AACC International · than the industry standard for sodium bi-carbonate ... product structure to maximize and maintain ... (American biscuit)

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S. Skellern, M. BriggS, k. Manning, and d. JordanKudos Blends Ltd.Kidderminster, Worcestershire, England

Salt reduction is a hot topic not only for commercial and artisanal bakeries, but

for consumers worldwide. Many recent conferences have addressed the impor-tance of reducing salt in all areas of food production. Salt, which has been branded a “silent killer,” has been linked to a signifi-cant increase in the prevalence of heart at-tacks, strokes, and other medical condi-tions associated with high blood pressure and hypertension (1,6). It is found in a wide variety of foods worldwide, and quantities are particularly high in pro-cessed foods (5). A high level of salt means a high level of sodium—the mineral re-sponsible for the negative health effects associated with salt consumption. It is not only processed foods that contain high lev-els of salt, however; bakery products can also contain high levels of sodium in ingre-dients that may not be obvious to consum-ers. The action group World Action for Salt and Health (WASH) has called for more awareness to be given to reducing salt con-sumption, stating that products need better labels (6). The detrimental effects of high sodium intake on health have motivated many food companies to develop innova-

➤ FEATURE

➤ Salt reduction is a hot topic for many food producers worldwide.

➤ Challenges previously associated with use of potassium bicarbonate as an alternative have been overcome.

➤ Increased potassium in the diet can provide many health benefits.

Sodium Reduction in the Baking Industry

tive ideas and ingredients to help reduce salt in their products. It has also inspired an increase in research into sodium, its effects on the body, and possible ways to reduce its overall consumption.

Salt and SodiumSalt is made up of sodium chloride, and

it is the sodium component that is respon-sible for the physiological effects of salt. Many familiar baked goods, such as bread and sweet bakery products, contain large amounts of sodium. Salt not only affects the flavor of products, to which we have become very accustomed, but it is an ex-tremely important contributor to an ex-tended shelf life. Sodium is a fundamental component of numerous chemical interac-tions that are used to produce modern baked products.

Sodium reduction is not simply a case of removing it entirely from the diet. Sodium is an important mineral in the diet and is vital to maintaining healthy function of the body (5). In the body sodium works syner-gistically in conjunction with potassium to help regulate blood pressure (4). These two minerals must be in balance in the body to regulate fluid levels and, in turn, blood pressure (4,5). Modern diets are often defi-cient in potassium but very high in sodium, leading to an imbalance that can result in an increase in blood pressure. This imbal-ance is something medical professionals are trying to address to improve health. Using innovative ingredients to bring these minerals back into balance is one way to help lower blood pressure and assist in re-ducing the prevalence of hypertension-re-lated medical conditions such as heart at-tacks and strokes (5,8). Understanding the vital interaction between sodium and po-tassium within the body is critical to devel-oping a strategy for reducing sodium in baked goods.

Salt is not the only component that con-tributes to the sodium levels found in sweet baked goods such as cakes and muffins. A number of other less recognized sources also exist. A large proportion of the sodium found in baked goods comes from the bak-ing powder or leavening agents used. Bak-ing powder is a complete leavening system that causes baked products to rise. It typi-

cally consists of acid and alkali compo-nents that react with each other to produce carbon dioxide gas bubbles, which cause the baked product to rise and expand. Most commonly, the alkali component is sodi-um bicarbonate, and the acid component is a phosphate leavening acid. In commercial bakeries, the phosphate tends to be sodium acid pyrophosphate (SAPP). Both compo-nents contribute significantly to the sodi-um content of baked goods: sodium bicar-bonate is 27.4% sodium, and SAPP is 20.4% sodium.

Sodium BicarbonateFor many years, sodium bicarbonate has

been the primary source of carbonate used by the baking industry (10). Its stability as a powder, pleasant flavor, and good func-tionality when used in a balanced leaven-ing blend has ensured that it has remained the primary choice for bakers (7). It is also extremely versatile and is available in many different grades that are suitable for a wide variety of applications. Various grades with different particle size distribu-tions are routinely used in the baking in-dustry. The variety of available particle sizes allows bakers flexibility in choosing the grade that is most suitable for an ap-plication. Additionally, for bakery applica-tions sodium bicarbonate can be treated with conditioners to obtain a free-flowing quality (FFQ). A very fine particle size combined with an FFQ is suitable for dough-type products in which there is less water available, because it provides full dispersion throughout the dough. A stan-dard grade has a fine particle size distribu-tion that is suitable for cake batters in which more water is available to hydrate the particles. Although stable and versa-tile, the high sodium content of sodium bicarbonate has prompted a search for ef-fective replacements.

Early sodium reduction strategies in-volved bakers simply removing added salt from their formulations. Although this re-duced the sodium content, it had drastic, negative effects on the shelf life and flavor of the end products (10). Salt is one of the most efficient means of extending and en-hancing shelf life because it draws out moisture, preventing food spoilage micro-

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organisms from growing (11). As a result, alternative methods of reducing sodium without having to remove added salt are required to maintain shelf life. If sodium from other sources can be reduced or re-moved from formulations, added salt can continue to be used to influence flavor, texture, rise, and other attributes of the fin-ished product.

Potassium BicarbonateIn the drive to decrease sodium con-

sumption, potassium bicarbonate has be-come increasingly popular as an alternative source of carbonate. Like its sodium coun-terpart, potassium bicarbonate is able to react with acidulants to generate carbon dioxide gas (3,10). Until recently potassi-um bicarbonate was only available as a coarse grade that had a particle size larger than the industry standard for sodium bi-carbonate (10). In addition, the hygroscop-ic nature of potassium bicarbonate and its inherent instability made it difficult to manufacture grades with finer particle sizes that would be suitable for use in the baking industry. Surface spotting, which results from the use of coarse potassium bicarbonate, is visually unacceptable. It is caused by partial dissolution of the carbon-ate, which leads to areas of high alkalinity (Fig. 1). This high alkalinity also decreases shelf life by increasing pH, which allows the acceleration of mold and bacterial growth.

Significant improvements in the stability of potassium bicarbonate have resulted in the creation of a variety of grades for bak-ery applications, similar to those available for sodium bicarbonate, that can be used to maximize end-product quality. Potassium bicarbonate with FFQ, similar to its sodi-um counterpart, has a very fine particle size that allows full dispersion and dissolu-tion in drier doughs in which less water is available. A fine grade has a particle size more suitable for batters in which more water is available to hydrate the particles. The improved solubility of the finer grades of potassium bicarbonate ensures maxi-mum dissolution in the dough or batter, allowing for maximum rise of baked goods and eliminating any unsightly spots associ-ated with uneven dissolution caused by coarser grades of potassium bicarbonate (Fig. 2).

SAPP and Potassium Biocarbonate. Use of potassium bicarbonate allows the continued use of SAPP, which is multi-functional and versatile and is available in a wide variety of reaction speeds that suit different bakery applications and provide more control over the baking process (3). Fast-reacting SAPP begins reacting sooner in the bakery process, as soon as it comes

in contact with liquid, and can be beneficial when maximum gas evolution is required during a short bake time (10). Slower react-ing SAPP begins reacting much later in the baking process and offers more process tolerance when used in applications with longer production cycles (10).

Utilizing different reaction speeds means that gas release can be manipulated to occur at specific points in the development of product structure to maximize and maintain product volume, shape, and internal struc-ture (3,10). Although they offer lower so-dium levels than SAPPs, calcium phos-phates do not have the same versatility in terms of reaction speeds. They tend to react quickly and, as a consequence, to react dur-ing the processing stage rather than the bak-ing stage. Calcium phosphate can be used in combination with slower reacting leav-ening acids. The use of potassium bicar-bonate with SAPP within a leavening sys-tem allows for sodium reduction while still utilizing the versatile functions of these phosphates.

Gas Value. The gas value is the amount of carbon dioxide released per gram of bi-

carbonate. Potassium bicarbonate has a slightly lower gas value (0.44 g of CO2/g) than sodium bicarbonate (0.52 g of CO2/g). This may be considered a negative when replacing sodium bicarbonate with potas-sium bicarbonate, because theoretically more potassium bicarbonate must be added to obtain the same effect. However, potas-sium bicarbonate dissolves more readily than sodium bicarbonate. In addition, more often than not, there is little benefit to in-creasing the addition of potassium bicar-bonate so the gas values match those of sodium bicarbonate, because a slightly acidic product can be beneficial in terms of flavor and shelf life.

Sodium Reduction Strategies Using Potassium Bicarbonate

Initially, issues with potassium bicar-bonate properties and stability caused con-cerns regarding its suitability for use in bakeries. Potassium bicarbonate is very hygroscopic; it readily absorbs moisture, which causes it to form solid blocks and renders it unusable, leading to problems with transportation and handling of potas-

Fig. 1. A scone (American biscuit) made with coarse potassium bicarbonate (A) exhibits uneven pH. The universal indicator shows areas of high alkalinity (dark green) caused by areas of unreacted bicarbonate. A scone made with potassium bicarbonate with a fine particle size (B) exhibits a more acidic and even pH. Even pH is a result of full dispersion and dissolution of the potassium bicarbonate.

Fig. 2. A, Scones made with coarse potassium bicarbonate (note the unsightly spots and poor volume); and B, scones made with fine potassium bicarbonate.

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sium bicarbonate powder. In addition, there is the potential for loss of carbon di-oxide through release, which results in a shorter shelf life and poor product volume. Processing aids can be added to maintain the free-flowing characteristics of the po-tassium bicarbonate powder and increase the inter-particle space. This helps prevent caking during storage by inhibiting mois-ture absorption and particle sintering. Markedly improved stability means that potassium bicarbonate that it is similar to sodium bicarbonate in terms of stability.

When used as a sodium reduction solu-tion, some bakers have noted unsatisfac-tory flavor qualities. Initially this was thought to be due to the use of potassium bicarbonate; however, there are many fac-tors that can affect product flavor when trying to reduce salt. Changes in flavor can be avoided or moderated using several methods:

1) When replacing sodium bicarbonate with potassium bicarbonate, added salt can be left in the formula. This causes little or no change in the flavor of products while still achieving salt reduction targets.

2) Coarse particle size in potassium bi-carbonate causes the formation of carbonate spots in baked goods, which, in turn, causes localized areas with high alkalinity and very strong metallic flavors. This can be avoided by using finer grades of potassium bicarbonate that can be fully dis-solved and dispersed throughout the dough.

3) Some bakeries have tried to go too far in reducing sodium—replacing all of the leavening components, in-cluding acidulants, with sodium-free versions. Sodium-free products are not required to meet sodium reduc-tion targets. Simply reducing sodium by 50% allows for a healthier product without compromising the flavor of the finished product.

Sensory research has been performed by a food research association on behalf of one of the United Kingdom’s leading leav-ening agent suppliers. An assessment of differences in flavor was made between products containing potassium bicarbonate and those containing sodium bicarbonate; both products had a particle size similar to

a baker’s-grade sodium bicarbonate such as USP #1. The results obtained showed that independent taste-test professionals could not detect any significant difference between product types or any unpleasant aftertaste.

Potassium bicarbonate with a fine parti-cle size matches the required functionality of sodium bicarbonate in terms of carbon dioxide release and exceptional stability. It is also available in a range of grades suit-able for bakery applications and can be used in products without affecting the quality, texture, flavor, appearance, or rise of baked goods. Replacement of sodium bicarbonate with potassium bicarbonate can achieve up to a 50% reduction in sodi-um levels.

Health Benefits of Potassium Bicarbonate

One major advantage to using potassi-um-based ingredients is the recognized health benefits associated with potassium in the diet. Potassium is a naturally occur-ring mineral that is abundant in many fruits and vegetables such as bananas, prunes, tomatoes, and potatoes. It is the third most abundant mineral in the body and is essen-

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tial for health and well being. Apart from being closely involved with sodium in maintaining healthy blood pressure, potas-sium can be used to reduce hypertension in sodium-sensitive individuals (1,2,5,9). Potassium has also been recognized for its role in helping to maintain healthy mus-cles (including the heart) and a healthy and efficient nervous system and in help-ing to reduce anxiety and stress levels in susceptible individuals (1,4,5,9).

Use of potassium bicarbonate in baking powders enables bakers to not only reduce sodium, but to incorporate an ingredient with potential health benefits. Simply pro-ducing a scone (American biscuit) with potassium bicarbonate rather than sodium bicarbonate may provide consumers with as much potassium as eating one-third of a banana (based on calculations of the po-tassium content of both products). Another major benefit of replacing sodium with potassium bicarbonate is that it contributes to the balance between the two minerals. Replacing only 50% of the sodium in a baked product with potassium will help in balancing these two minerals (9).

ConclusionsExchanging sodium bicarbonate for po-

tassium bicarbonate can help bakers reach their salt reduction targets and create healthier baked goods. Recent advances in technology have improved this carbonate source so it now matches its sodium coun-terpart in functionality and versatility. Al-though potassium bicarbonate is hygro-scopic and can be difficult to handle, ad-vances in potassium bicarbonate product formulations have led to a powder that is very stable, free flowing, and available in a wide range of particle sizes.

The future of potassium bicarbonate in the baking industry should not be underes-timated. It can not only help bakers to re-duce salt in their baked products without compromising product quality, but can also provide added health benefits by in-creasing the amount of potassium in the diet.

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Steph Skellern is the technical manager at Kudos Blends, and the main focus of her role is sodium reduction in the baking in-dustry. Since joining Kudos Blends, Skellern has been heavily involved in the development and patenting of KUDOS potassi-um bicarbonate—a sodium-free bicarbonate source that has been specifically developed for the baking industry. She is keen to promote the health benefits of increasing potassium in the diet and reducing sodium consumption, and she is involved in a number of global initiatives on these subjects. She has a B.S. (honors) degree in biological sciences from the University of West England. Skellern can be contacted at [email protected].

Dinnie Jordan is the founder and director of Kudos Blends. She established the business in 1999 with the vision to develop technically driven leavening agents. Prior to this, Jordan worked in the bakery phosphates industry, and it was here that she identified the opportunity to provide bakeries with technically advanced, uniquely functional leavening agents. She is an es-tablished thought leader on baking processes, sodium reduc-tion, and the positive health implications of potassium in the diet. Her leadership, vision, and innovation has helped Kudos Blends to become an international business, counting some of the world’s leading bakeries as customers. Jordan has a B.S. (honors) degree in chemistry from Wolverhampton University, England. Jordan is an AACC Intl. member and can be contacted at [email protected].

Michelle Briggs is the technical service and NPD manager at Kudos Blends. She has a B.S. (honors) degree in science from De Montford University in Leicester, England, and she has more than 10 years of experience in the baking industry. With in-depth knowledge of baking powders and bakery processes, Briggs is responsible for new product development to keep the Kudos Blends product portfolio at the leading edge of the market. She also provides consultancy and support to customers on sub-jects that include baking powder selection, recipe formulation, product manufacture, HACCP, and food safety. Briggs’ main area of interest is leavening agents, particularly chemical leav-ening systems. Briggs can be contacted at [email protected].

Karen Manning is the operations manager at Kudos Blends, with responsibility for manufacturing, logistics, product safety, GMP, HACCP, and food safety. Quality is a critical element of Manning’s role, and she manages and develops the quality systems for all areas of the business. She has a B.S. (honors) degree in food science and nutrition from the University of Sur-rey, England, and she has more than 15 years of experience working in the food and beverage industries. It is this experience that makes Manning a pivotal part of the Kudos Blends busi-ness—directing new product development and continuous innovation to improve the quality of everything that Kudos Blends does. Manning can be contacted at [email protected].

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