Innovations in flour milling

by Teresa Acklin
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French miller Grands Moulins de Paris builds new mill with advancements designed to improve materials tracking ability, food safety assurance.

By Diane Montague, European correspondent

   Food safety and traceability have become major issues in the food and farming industries in the past few years. In Europe in particular, concerns over “mad cow disease,” salmonella and E. coli have grown alongside changing public attitudes towards farming methods, animal welfare and the environment. As consumers become more prosperous, they take a closer interest in how food is produced and how safe it is to eat. The food and farming industries are beginning to realize that they ignore these trends at their peril.

   A company at the leading edge of this change is one of France's largest flour millers, Grands Moulins de Paris. The company has recently completed implementation of a strategy that provides complete traceability through all stages of wheat and flour production, from field to flour bag, and that is claimed to be able to identify the source of any grain sample at any stage of processing within one minute.

   The development has been made possible through the establishment of partnership agreements with farming cooperatives that act as the link between G.M.P. and the cereal growers. These agreements were the brainchild of G.M.P.'s managing director, Michel Crignon, who introduced them in 1991.

   “The companies in our industry who will succeed in the future will be those who respond to consumer demands for quality and safety,” says Mr. Crignon. “Only those manufacturers capable of organizing full traceabilty of their raw materials will be able to meet the concerns of consumers.”

   In the first year, two partners supplied 10% of G.M.P.'s wheat requirements. Since then, the partnerships have been increased gradually to 36 organizations that now supply 100% of G.M.P.'s wheat requirements. Starting with the seed, G.M.P. works with plant breeders to conduct research on new varieties for specific characteristics. Moving on to the farm, the company provides advance financing for certified seed — of which nearly 20,000 hectares were sown last year — to encourage farmers to sow high quality seed with a proven level of varietal purity.

   The company specifies the crop rotations that can be used, the varieties to be sown and the precise use of fertilizers and crop protection treatments. At harvesting, two specialists work with the co-ops to check that the crop has reached the right stage for harvest in terms of degree of ripeness and moisture content.

   Each trailer-load is sampled coming off the field by the silo manager on delivery to the co-op. At the silo, varieties are sorted, cleaned and treated for storage with specified crop protection products.

   Samples of wheat from the harvest are test-baked by G.M.P., which then specifies the blends required from the co-op that are needed to meet customer requirements. Once the blends have been made up by the co-op, the wheat is delivered to the mill, where it is sorted and cleaned a second time.

   Samples are analyzed at each stage of production so that, at any moment in time, staff can identify the batch of wheat used. All transport must meet specified hygiene standards, and flour trucks must provide records of washing programs.

   Full scale operation of the partnership system of wheat supplies is now in operation at all mills, but the construction of a complete new mill on the outskirts of Paris has enabled G.M.P. to introduce advanced production techniques that improve the traceability even further.

   The largest new milling complex to be built in France for more than 50 years was officially opened in 1997 by G.M.P. Built at Gennevilliers, the commercial port of Paris on the Seine just 5 km from the city center, the plant replaces G.M.P.'s old mill in the center of Paris, which the company had to vacate following changes in planning regulations.

   The Paris-Gennevilliers mill is the largest of the 14 owned by G.M.P. which, since 1989, has been a subsidiary of the Bouygues Group, an international organization whose main activities are in building construction and communications services. G.M.P., with a turnover last year of French franc 2.4 billion (U.S.$399 million), is the second largest French-based flour miller after Groupe Soufflet, but the largest in the French market.

   G.M.P. supplies 10,000 independent bakers in France, exports to 60 countries worldwide through its international trading company C.F.C.F., and produces a range of frozen products for professional bakers, patissiers and caterers with a European network in all European countries. Total exports represent 35% of the company's turnover.

   To supply the expanding European market, G.M.P. has several plants outside France, among them one in Wigston, U.K.; and one at Ridderkerk, the Netherlands, which recently was enlarged to produce the equivalent of 2,700 baguettes an hour. G.M.P.'s newest area of development is the Delifrance Boulangerie et Cafe Francais shops, which sell the company's own range of bakery products. These are opening up in all European countries and rapidly expanding in the Near East, Middle East, West Indies and Eastern countries and as a joint venture in Asia.

   In addition to supervising every stage of wheat and flour production, G.M.P. runs training schools for bakery and patisserie students and provides finance and financial advice services to its customers.

   The new mill at Paris-Gennevilliers has been designed specifically for the production, packaging and dispatch of flour to French bakeries and international customers. Production for G.M.P.'s industrial customers is now centered at the company's other site at Verneuil. The baking and pastry school has been enlarged and moved to the Bercy Expo site in Paris. Given only two years to vacate the old center-city location, G.M.P. decided on Gennevilliers, where an existing grain silo installation provided an ideal situation because the 5.4-hectare site features good access by road, rail and, most importantly, water. With some 50% of production going for export, the Seine port has enabled the company to develop its policy of making increasing use of water transport for both internal movements and export.

      New design, new systems.

   The new mill complex was completed in just a year, after a six month planning period, and it provided a fresh challenge for milling engineers Buhler A.G., Uzwil, Switzerland, whose equipment G.M.P. has been using for the past 70 years and who was responsible for the design and construction of the new mill. The decision to retain and renovate the existing silos, which were in two separate blocks, meant the manufacturing unit had to be fitted into the gap between.

   G.M.P. wanted two mills so that one could be used exclusively for domestic flour production and one for export. The solution was to have two mills built one on top of the other in a central tower with a floor area of only 100 square meters on each floor. This is the first time that such a configuration has been attempted by Buhler.

   The two mills have different flow schemes to produce different end products. Moulin 1 operates 11 rollermills, of which three are type MDDL eight-roller mills, while Moulin 2 grinds with four eight-roller mills and six type MDDK four-roller mills.

   The two milling units, each with a capacity of 400 tonnes per 24 hours, run continuously 24 hours a day, seven days a week, producing 200,000 tonnes of flour a year. On the east side of the milling units is the silo storage for 12,000 tonnes of wheat, and on the west side is storage for 8,000 tonnes of flour. The flour storage area is divided into 41 compartments so that blends can be mixed according to specific customer requirements.

   G.M.P.'s policy of producing a wide range of products has been at the center of a number of innovations both in production technology and material supplies to provide maximum flexibility and traceability. The mills produce 100 types of flour and 150 mixtures, which can be packed in bag sizes ranging from 500 grams to 50 kilograms or filled up in big bags of up to 1000 kg.

   The complex operation of handling a wide range of blends has been dealt with by incorporating a continuous and a batch mixing system. The two continuous blending and mixing plants for bakery flour with a capacity of 20 tonnes per hour each work with differential proportioning Transflowtron scales for the main flour and with micro-differential proportioning scales for gluten, flour and bread improvers.

   The batch system for the production of ready mixes incorporates a system that until now has been used only in the pharmaceutical industry. In this system, a mixer tank moves along a rail track to each ingredient silo in sequence. The silo releases a measured amount of material into the tank, which then moves on to the next silo outlet.

   Material can be drawn from any of 84 silos, each containing a different ingredient, and can then be added in quantities ranging from 10 gm to 1 tonne. Once all the materials have been added, the mixing tank is lifted up to the blender unit. Materials are analyzed at each stage of production to provide total traceability at all stages.

   A large portion of the continuously blended flours and micro-ingredients that have been homogeneously mixed in an in-line blender and monitored in a near-infrared on-line measuring and control unit is conveyed to one of the eight bulk loading bins. A smaller portion of the continuously blended flour and a larger portion of the batch blended material are transferred to one of five packing lines — the largest of its kind for handling small bags in France.

   After packing and stacking on pallets, the bags are moved to the finished product store, a 5,000-tonne storage area that has been designed to handle 350 different products. It is controlled by a system of bar codes on racks and pallets that are read by electronic scanners linked to screens in fork lift trucks.

   In another technical innovation, the computer locates the pallet and its position. The screen in the fork lift truck then calculates the optimal distance between each pallet so the driver can avoid unnecessary maneuvers.

   Products for dispatch can go either by road, rail or increasingly by water. The storage building opens directly onto the quays on the Seine. Boats are loaded under a full-length canopy — the first of its kind to be built out over water in France — that protects the cargoes from rain and contamination.

   Bags are loaded onto barges in slings. Loading capacity is a l,000-tonne barge per day, equivalent, as G.M.P. points out, to 40 rail cars. From there, the barges can go down the Seine to Rouen, Le Havre in western France, or directly to final destinations. This year, G.M.P. expects to export 100,000 tonnes from Gennevilliers, much of it by inland waterways.

Grands Moulins de Paris Fact Sheet
Parent companyBouygues S.A.
Turnover in 1997FFr2.4 billion (U.S.$399 million)
of which
Flour, durum and branFFr1.622 billion (U.S.$269 million)
Frozen pre-baked breadFFr428 million (U.S.$71 million)
Ready to bake croissantFFr204 million (U.S.$33 million)
Frozen pastries and savoriesFFr159 million (U.S.$26.5 million)
Production units14 flour mills throughout France and Belgium
11 frozen food plants in France, Belgium, Sweden,
the Netherlands and the United Kingdom
Production600,000 tonnes of flour