All living things require nourishment, and people get most of the energy needed to sustain life from food consumption. For many, food security is a constant problem, and obtaining food is a daily struggle. The Food and Agriculture Organization of the United Nations estimates that 868 million people in the world are malnourished, which has been linked to an increased risks in illness, underdevelopment of bone and tissue, and poor mental health. In recent research Cook et. al. concluded that even people with marginal food security were at an increased risk than previously thought for adverse health and development outcomes.[2} This problem is further complicated by the geographic location of the people most effected by starvation compared to the location of the food surpluses that exist worldwide. Oftentimes a high percentage of the food being delivered to the people in need spoils because of the long spans of time it takes to reach those with shortages. Long term efforts are being made, moving food sources closer to impoverished people, but short term remediation is also required to get the people food supplies that are both plentiful and storable.
Food manufacturers are playing a vital role in fighting food insecurity by adapting their current manufacturing practices to incorporate longer shelf life demands while maintaining high quality products that consumers enjoy. This includes more stringent protocols for making goods, as well as an increase in quality checks for the final products. One of the key components that requires control is water. If products have too much moisture then there is an increased risk for molding and spoilage. If too little water is present then the product may be brittle and have an unsuitable taste. But how is moisture content reliably determined?
The Association of Agricultural Chemists (AOAC) has been publishing quality testing methods in food products since 1912. Currently these methods for moisture determination use loss-on-drying technology and often require the use convection ovens and/or vacuum ovens, as well as having sample testing times over one hour. These methods are accurate, but the lengthy processing times slow the rate of production. Additionally, these methods don’t allow for dynamic in-test metrics that help provide a complete profile of the sample as it is being examined.
Rapid loss-on-drying instruments operate using the same principle as traditional oven methods, but are able to address the drawbacks associated to them without changing the ease of use. Users of these instruments place a prescribed amount of material onto a pan that is sitting on a balance. Once the correct amount of material is on the pan the instrument heats up to a specified temperature and the water is evolved off of the sample. Multiple criteria can be used to end the test, but frequently tests are ended when the change in mass is determined to be negligible. These tests provide the user with real time measurements and often tests take a few minutes instead of hours.
Comparative testing was conducted for various products using the Computrac® Loss-On-Drying line of instruments, and a vacuum oven with a procedure similar to AOAC method 925_09. The vacuum oven was set to 70°C and at full vacuum. The Computrac® testing used individual parameters stored in the instrument under the names from the table. The samples tested were prepackaged foods that have a 6 year shelf life on the package. Both testing methods used 4g of sample and were tested.
Table 1. Comparison of moisture results from loss-on-drying method using a vacuum oven and a Computrac® Rapid Loss-On-Drying instrument.
Graph1. In-situ measurement data from a rapid loss-on-drying test performed with a Computrac® MAX® 4000XL instrument. The test ended at 300 seconds when the test’s ending criteria was met.
For testing shelf stable food products, rapid loss-on-drying instrumentation has proven to provide a more desirable method of moisture measurement when compared to traditional loss-on-drying techniques. It addresses the drawbacks associated with conventional loss-on-drying and while maintaining the ease of use application. The reduction in test times increases manufacturing efficiency while simultaneously reducing energy costs. Additionally, this instrumentation is able to provide real time moisture measurements to help users optimize moisture measurement methods. These reductions and savings can be used to deploy food to those in need more quickly, and reach more people that presently have poor food security.