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Wheat flour is the major ingredient in all baked products. It is therefore inevitable that flour quality has a major influence on product quality. In Baketran’s* recent survey of the South African industry, flour quality unsurprisingly featured as one of the critical issues in the industry, and that measures are available to counteract the resultant quality issues.

“While there is a commonly expressed view that South African wheats are ‘too strong’ for current breadmaking requirements,” say the researchers in the report. “For example, they require higher energy inputs than can be delivered by current bakery practice.” In addition, the geographical impact on wheat grown in South Africa cannot be ignored - in the Cape Region, wheat flours would not commonly be considered excessively strong. In addition there is the impact that imported wheats (generally of the stronger type) have on gristing in the flour mills and the quality of flour delivered to the baker.

International Fine Ingredients (IFI) specialises in solutions for bakers, by combining years of experience and expert global support with effective enzymes and preservatives from the world’s leading manufacturers. IFI’s new release of VERON® HF from AB Enzymes allows you to replace 50% of the gluten in bakery formulations, thereby reducing costs substantially - without any loss in quality. The multifunctional enzyme preparation can be used in many different recipes and provides extraordinarily good performance in mixed flour/dough systems like wheat and/or rye. It is also suitable for high fibre baked goods using dietary fibres like oatmeal, cornmeal, soya flour etc. VERON® HF has a distinct stabilizing effect on dough systems, and the final baked goods also have an attractive baking volume with excellent break-and-shred properties.

For the wheat breeder, the business of developing new wheat varieties is long and complicated. Typically 12-15 years may elapse before a successful introduction. The breeder must balance many different plant attributes related to plant viability, agricultural robustness, yield for the farmer and of course end-performance characteristics for the baker. Defining end-use performance criteria has always been problematical and there has been a tendency to concentrate on protein content with the expectation that higher protein contents will deliver better protein qualities.

This approach, along with other factors, may have led to a lack of appreciation of the contribution that protein quality, delivered via the gluten rheological characteristics, may make to achieving final product quality in modern breadmaking. In part this apparent lack of awareness may have arisen because the oxidation systems used in the past, typically a combination of potassium bromate and ascorbic acid, may have masked the role that gluten quality played. There is no doubt that the current reliance on ascorbic acid as the sole oxidant in breadmaking has resulted in observable changes in dough rheology. This underlying change in the oxidant system has been accompanied by other changes in improver ingredients, most notable of which has been greater use of a wide variety of enzymes. Collectively these formulation changes have enabled bakers to continue to make bread of the appropriate quality but have made effective predictive testing of wheat and flour properties, including test baking, more difficult to achieve - and may explain concerns over the appropriateness of current testing methods. Finding and identifying appropriate wheat flour testing methods will always be difficult because it is in the nature of commercial baking that changes to ingredients and methods will change with time.

The delivery of suitable end-performance characteristics by new wheat varieties will remain critical in contributing to baked product quality, and the need for the constant development of new wheat varieties important to the milling and baking industries in South Africa. However, the inevitably long time taken to identify, grow and commercially develop new wheat varieties limits the likelihood that answers to the immediate technical needs of the baking industry will come from the wheat.

The quality of flour is high on the international research agenda, too. Dr Terry Sharp - Head of Baking & Cereals Processing Department of the Campden & Chorleywood Food Research Association (CCFRA) visited South Africa earlier this year. One of the events hosted in collaboration with Anchor Yeast was the "Grain Chain" Forum, which identified issues and possibilities for improvements in the South African supply chain from wheat to baked products.

CCFRA is actively involved in research projects relating to the quality of flour and baked goods. Over a period of five years the project team identified key relationships between wheat variety composition as well as processing quality and flour performance. In particular, it was possible to identify markers on individual chromosomes in the make-up of some wheat varieties which could be related to characteristics such as yield, protein content and milling performance.

Since 2000, CCFRA has also run a series of research projects on enzymes for bakery products, with the aim to determine the impact of enzymes on the product quality and nutritional balance. The results show that the cellulase enzyme converts the insoluble fibre into a soluble form doubling the amount present in both white and wholemeal bread. While not all enzymes perform in the same manner, it is useful to know that enzymes can change the nutritional status of bread.

In another CCFRA research project, tests were developed to help companies make better use of flour improvers to enhance the quality of their baked goods. In breadmaking, for example, xylanases can improve loaf volume and crumb texture by solubilising wheat cell wall polysaccharides and improving gluten performance. But wheat flour naturally contains several components that inhibit xylanases - limiting the usefulness of commercial xylanase preparations.

The new tests will enable millers and bakers to measure this inhibition and optimise xylanase usage. They allow comparison of the effects on xylanase activity of different batches of wheat. By assessing the ratio of activity of a pure xylanase extract to its reduced activity on addition to flour, the inhibition is expressed as a simple 'relative inhibitor activity'. The approach also allows comparisons between different batches of wheat to assess natural variation in the effect of endogenous enzyme inhibitors between harvest years, to see how this contributes to observed differences in flour quality. The understanding of xylanase inhibition that this project is generating will help companies to pre-empt problems in using these flour improvers whilst the objective measurement of inhibition will facilitate better communication between supply chain partners.

Addressing flour quality through new wheat varieties remain a long term solution. In the short-term, bakers have to employ other methods to cope with the fluctuations in flour quality. Fortunately, technology has resulted in a range of flour extenders, conditioners, improvers, additives and preservatives to address issues surrounding flour quality. While it is widely known that the baking properties of the flour improve when it is stored for some time after grinding, due to the oxidation of proteins by the oxygen in the air, today's pressing production demands rarely allows time for storage and oxidation. In addition, the oxidation that occurs naturally is limited.

Product quality is often associated with glutens, the protein component of flours, and gluten proteins contain chemical groups that react with oxidising agents. The cross linking reaction increases the size of the protein molecules resulting in the improvement in product quality at a molecular level.

Most flour improvers are oxidants and these produce a far greater degree of oxidation. One of the most common oxidisers used was potassium bromate, which has now been banned in many countries, including South Africa. It has been replaced by the use of enzymes. Other oxidising agents include persulfate, bromain, iodate, and nitrogen trichloride, all of which affect protease activity and gluten properties.

Another common flour improver is ascorbic acid or vitamin C, which is harmless and completely decomposes in the baking process. Although it performs the same function, ascorbic acid is not an oxider. When mixed with the oxygen in the air, ascorbic acid is converted to dehydroascorbic acid, DHA, which is an oxidising agent.

Since the improvement of quality is related to the cross linking of gluten proteins, enzymes are also used to improve flour quality. In the production of bakery products, the activity of the enzymes present in the flour is not always sufficient to ensure the necessary formation of sugars in the breakdown of proteins in the dough.

International Fine Ingredients (IFI) the agent of AB Enzymes Germany is offering a wide range of enzymes to optimize the flour compounds and the baking performance of the flour.

Alpha amylases to optimize the gassing power of yeast by providing more fermentable sugars as substrate.
Specific xylanases to improve dough and fermentation stability in order to obtain a high baking volume.
High performing amylases to increase the shelf life of baked goods.
Cellulases for high fibre and rye breads especially for the improvement of the dough properties.
Proteases for tailor made flours to be used in the biscuit and wafer industry.
Enzymatic cocktails to reduce or replace ingredients like emulsifiers or gluten.

IFI, together with its expert suppliers, is totally focused on the results that bakers need for enzymes and preservatives - both in quality and costs. Whether you need technical assistance, a reliable supply of ingredients or innovative solutions - you can find it all at IFI.

*Reference Stan Cuvain and Linda Young. A survey of current problems in and future research priorities for the SA baking industry. Baketran, on behalf of the Winter Cereals Trust. 2007.