HARARE, ZIMBABWE — The wheat market in Zimbabwe is undergoing radical changes. To encourage self-sufficiency in the provision of wheat and reduce the country’s import quota, the government has liberalized the strictly regulated market. Greater involvement on the part of both the state and private enterprises is one of the reasons why considerably more local wheat has found its way onto the market in recent years. The fluctuating flour qualities and lower protein levels of the regional wheat varieties can be counteracted with suitable flour treatment.
Bread plays a central role in the diet of consumers in Zimbabwe. The product of choice is sliced white bread, soft and fluffy, that serves as toast for breakfast and as a filled sandwich for lunch.
A large proportion of the wheat processed originates from the United States, Canada and Europe. But in the past, the high inflation rate and constant monetary crises in Zimbabwe often led to foreign currency shortages that disrupted imports and caused a rise in the cost of food.
To brace itself against supply problems and reduce dependence on imports, the government has introduced a number of measures to promote domestic wheat farming.
The core element of the reforms is liberalization of the raw materials market. For a long time, wheat growing and trading were solely in the hands of the government; but for several years now, private market players have been able to participate in the financing, production and sale of staple foods such as maize, wheat and soy.
One important market player is the Food Crop Contractors Association (FCCA), a consortium made up of raw materials traders, banks, mills and other interested parties. According to the FCCA, three-quarters of Zimbabwe’s wheat crop already was financed by private companies in 2023. The volumes harvested have increased noticeably. While 375,131 tonnes of home-grown wheat were produced in 2022, a record crop of 408,000 tonnes is expected for 2023.
Moreover, the area under cultivation with wheat continues to grow. According to the Ministry of Agriculture, it increased from 66,000 hectares in 2021 to 86,000 hectares in 2023.
Fluctuating flour quality
Unfortunately, the increasing domestic wheat production has a downside. The wide diversity of the domestic varieties results in fluctuating product quality. Moreover, wheat grown in Zimbabwe has noticeably poorer baking properties than hard red winter (or spring) wheat from the United States or Canada, for example.
Where the baking industry is concerned, the partial use of domestic wheat flour makes many demands on the production of high-volume pan loaves. Mixing high-performance imported wheat with lots that have weaker protein results in changes, for example to the fermentation stability, crumb structure and size of the loaves.
On the other hand, consumers have clearly defined expectations regarding their favorite bread. Sandwich loaves must have a large volume, a fine, even texture and a soft, fluffy crumb.
Tailor-made flour treatment
If the proportion of imported wheat is reduced, fine tuning of the flour with flour improvers is essential to maintain the expected standard of the products. Since the greater part of the flour will be used to produce sandwich loaves, emphasis must be placed on quality parameters such as volume, fermentation stability and crumb formation.
MC Mühlenchemie has cooperated closely with the milling industry of Zimbabwe for many years and supports its clients with tailor-made solutions geared individually to the needs of the mills and their customer base. Which flour treatments are to be used depends not least on the customer structure of the mills.
As a rule, Zimbabwe’s industrial bakeries have a good knowledge of flour treatment and often carry out the fine tuning of the flour themselves. For this circle of clients, basic treatment at the mill consists largely in standardization with individual enzymes such as amylases, hemicellulases, lipases or glucose oxidases.
Small artisan bakeries in the townships have a need for more extensive support in respect of raw materials. For such cases, the mills use complex enzyme systems or choose compounds that contain ascorbic acid, hydrocolloids, emulsifiers or wheat gluten as well as enzymes.
The poorer gluten properties and lower protein values of the local wheat can be compensated for with the enzyme systems and additives from MC Mühlenchemie. The specification used in a particular case will depend on the customer’s particular requirements and the rheological analyses and baking trials carried out at Mühlenchemie’s laboratories. The enzyme designers draw up an individual master plan for each flour.
Flour color a political issue
A further cause of discussion at Zimbabwe’s mills is currently the color of the local wheat. Since some domestic wheat varieties result in flour with a slightly yellowish color, the mills fear a loss of quality in the products baked from it.
As the online service “Businessweekly.co.zw” reported at the beginning of December 2023, the Grain Millers Association of Zimbabwe (GMAZ) lodged an official complaint with the Ministry of Agriculture and requested the government authority to issue a statement concerning the problem with this raw material.
As an acknowledged expert on flour, MC Mühlenchemie offers practical solutions to problems of this kind, too. Its wide range of products includes specific flour improvers that have brightening properties and give flours with a yellowish or greyish tinge a lighter appearance.
Composite flour reduces cost
Besides exploring new mixture ratios for imported and locally grown wheat, the African milling industry is currently turning its attention to the subject of “composite flour” as an economical alternative.
In Zimbabwe, which has a long tradition of growing and processing maize, the emphasis is on the use of maize flour. Especially for mills with flexible plant systems that can grind maize as well as wheat, the production of flour mixtures promises to be an interesting niche application. This option offers the mills greater scope for the use of different cereal types and it widens their profit margin since home-grown maize is usually much cheaper than imported wheat.
However, from the baker’s point of view, the addition of too much maize flour has negative effects on the processing characteristics of the doughs and the quality of the baked foods. Among other things, the reduced gluten component of the protein affects the water absorption and fermentation stability of the dough, and in the case of sandwich loaves it results in a denser crumb structure and a smaller volume. It also changes the color, taste and shelf life of the products.
To prevent such a loss of quality, millers have to use their instinct and intuition to discover the right ratio of wheat flour to non-wheat flour in the mixture and make up for the poorer baking performance with suitable enzymes and additives.
Compozym boosts flour performance
At its Technology Centre, MC Mühlenchemie carried out comprehensive applications trials with non-wheat flours. The main objective was to produce sandwich loaves capable of competing with pure wheat products in respect of appearance and taste.
It was products from the Compozym series that showed themselves to be the additives of choice. With specific modifications geared precisely to the flour mixture, it became possible to devise highly functional solutions to produce composite flour loaves.
Important quality parameters such as volume, water absorption capacity, oven rise, machinability and elasticity of the crumb improved so strikingly that it became possible to use 20% maize flour successfully.
Problems and solutions
For Zimbabwe and many other countries, the partial use of non-wheat flours or domestic wheat varieties may offer a promising way of achieving greater independence in the procurement of raw materials.
But the success or failure of such milling strategies does not depend on the mills alone; it also involves the downstream processors on the spot. Since novel flour mixtures often cause difficulties in preparing the dough and fluctuations in product quality at the bakeries, the technologists from MC Mühlenchemie offer their services as consultants to the baking industry, too.
Where sandwich bread production is concerned, the main problems lie in an unsatisfactory crumb structure and misshapen loaves. To trace the source of error, it is necessary to analyze all the process parameters thoroughly in each specific case. Nevertheless, there are some basic recommendations that may help to prevent such faults in the products.
The following is an overview of the most common weaknesses found in the production of sandwich loaves:
Problem: Large pores and uneven texture of the crumb.
Solution: More intensive kneading and longer proofing; adjust the fat content of the recipe. Add emulsifiers (e.g. Mulgaprime SSL / Mulgaprime 90) and enzymes (e.g. Alphamalt EFX Swift).
Problem: Collapse of the side walls of the loaves.
Solution: Change the mixing/kneading time; reduce the proof time; reduce amylases; increase the ascorbic acid content (e.g. Elco C-100); add glucose oxidase (e.g. Alphamalt Gloxy 14080), improve the structure of the dough with MCgluten Enhancer. Shape the dough by the four-pieces or twist method.
Problem: Rapid staling, inadequate shelf life.
Solution: Optimize pasting of the starch; improve water binding in the dough. Increase the amylase activity (e.g. with Alphamalt A 15140). Prolong the softness and elasticity of the crumb (e.g. Alphamalt Fresh).
Problem: Sticky dough.
Solution: Adjust water absorption; add improvers that increase water retention and reduce the stickiness of the dough (e.g. MCbest WA).
Problem/challenge: A desire for overall quality improvement in respect of volume, browning, machinability, texture and shelf life.
Solution: Treat the flour with “all-in” improvers from the Powerzym range.
Sven Mattutat is a product manager with Mühlenchemie. He may be reached at smattutat@stern-wywiol-gruppe.de for more information on this topic.
