New Processes for Making Clean Label and Healthy Carbohydrates

Modification of starch is carried out in order to obtain or to enhance certain functional assets for specific food or non-food modifications. Modification can be done via chemically, enzymatically and physical-(chemically) process techniques. Most enzymatic and chemical modifications are carried out in slurry, in which water acts as a reaction medium between the starch and the reagent. On the contrary, physical and physical-chemical modification of starch is mainly done under semi-dry or dry conditions, for example alkaline roasting or pyrodextrination.

Most of the currently produced functionalized starches are produced by means of chemically processes, e.g. ester- and etherification. A growing trend in food culture is the reduction or elimination of chemically modified food ingredients in food stuff. This demands from industry to follow a clean label modification and reformulation strategy. Physical modification of starch offers a potential for making clean label ingredients, as it does not require the usage of additional chemicals. It solely uses temperature, pressure, moisture. An example is thermally inhibition for making visco-stable starches that can replace chemically modified crosslinked starches.

Another trend in food is health, as research over the last decennia points out to a relationship between the intake of certain food and diseases such as, e.g. diabetes type II, high blood pressure, coronary diseases etc. Food that is rich in dietary fiber, low in calorie and salt is favored for providing a balanced and healthy food diet. Physical chemical modification offer a potential for making healthy carbohydrates that contribute to calorie reduction in combination with an increase in dietary fiber. Pyrodextrination is a physical-chemical modification technique, in which under acid conditions in combination with heat and moisture, the starch is hydrolyzed, re-polymerized and re-arranged (transglucosidation). The latter affect the digestibility of the starch and results in a higher total dietary fiber level (TDF).

Although most of these processes are known for quite some time (some are developed over a century ago), it turns out that in the practical situations these processes are not easily to be controlled and to scale up. This can cause losses in quality and functionality. For example, a poor control of the pyrodextrination process can cause formation of undesirable side components that need to be removed out of the final product.

In order to improve these processes it is therefore essential to get a better insight how to control the prime reaction parameters. In general, temperature and pressure are easily to adjust but water is a different story. Its physical state and its role in the reaction mechanism are affected by the other reaction parameters. In the last couple of years, TNO has put a lot of effort to get more insight in how to control this.

In this presentation TNO will address new and improved methods for physical chemical modification of starches, leading to a better control of the process and enhanced functional properties.