The production of breads, rolls, crackers and cookies, and other sweet goods, entail a sequence of production steps involving biological, chemical and physical reactions. These steps must occur in order and at precise time and temperature conditions. There are requirements for process water conditions which can have great effects on the fermentation and the rest of the upstream process. The mechanics of high speed mixing on the development of the gluten protein in the flour which will produce the final product structure, involves many physical and chemical changes. The precise controlled rate of the yeast fermentation is also of critical importance. At the same time that the various steps require precise monitoring and control, we are still dealing with a process which contains as much "art" as it does science. Therein is the technology challenge for manufacturers of process technology.

Some parts of the process are well understood, and suitable sensors and control systems exist. However, there are still many areas where systems need development, or perhaps refinement. A few will be described here, but an in depth discussion is needed to fully ascertain the needs and issues related to these technologies. A typical bread production line will run at 6-10,000 pounds per hour, with each step requiring sequence and process control to prevent what can amount to sizable production losses if the process gets out of control.

Biological Systems

The trick is to measure the fermentation rate in a mass of dough, similar to a plastic material, and the placement of any sensors must average the overall effect, and not be dependent on the environment of one particular gas cell. Some work was done a few years ago using gas chromatography and mass spectroscopy, using specially designed multi point sensors. This area still needs more development.

In addition to yeast metabolism, there are numerous enzymes, both indigenous to the process, and others added as processing aids, which need monitoring and control. Some technology to reduce the staling process is understood from the biochemical standpoint, but the ability to monitor and control the activity level, hinders commercialization.

Chemical Systems

In terms of one of the primary ingredients, water, the chemical parameters are absolutely critical. Hardness, pH, etc. can have big effects with small changes. In terms of cracker and cake products, many manufacturers use chemical leavening (baking powder and soda) either exclusively, or in conjunction with yeast fermentation. This obviously adds a whole different dimension to controlling the process. In order to retard premature spoilage and molding in the stores and at home, various mold control agents are used. These ,however, greatly affect the live yeast cells as well, and must be factored into the process control equation.

Some products may also receive a post-bake spray of various flavors, or other preserving agents, and must be monitored very carefully, with the appropriate level present after the very hot product cools. So, evaporative loss must be measured and controlled, as a function of the oven exit temperature.

When all these factors, and many others, are coupled to the physical changes which take place during process, packaging and shelf life, one can see the intricacy of a complex process. New and better sensors and control systems, integrated into the entire process, could make a major step forward in improving process control and product quality, as well as economic improvements in production. Improvements in these areas would move the production of bakery products more into the "science" arena, without sacrificing the "art" of good tasting baked goods.