- Winter 1997 "Update" Newsletter Article -
Study features measurements of moisture in grape product
From CATI Publication #970101
Copyright © 1997. All rights reserved.
Theoretical research on moisture content measurements at Fresno State could help the food processing industry in efforts to save time and expense.
A student/faculty research team working under the Viticulture and Enology Research Center (VERC) has compared the results of mathematical and actual methods of determining final moisture content of a dehydrated product. Initial results show that the mathematical model predicts moisture content accurately and with less variance than a conventional vacuum-oven drying method.
The work was done on samples of Thompson Seedless grapes dried using VERC's patented microwave vacuum (MIVAC) technology. Industrial technology professor Matthew Yen and graduate student Huai-wen Yang tested the mathematical model as a method of saving a step in determining moisture content of dehydrated products.
In conventional processing systems, moisture content of a product is often measured twice, before and after "dehydration" (even after processing, most products still retain a small amount of moisture). The content is determined by weighing each sample, evaporating all the moisture out, then weighing it again. The mathematical model could save the second measuring process by predicting the final moisture content based simply on initial moisture content and weights.
The formula "can be applied to products other than Grape PuffsTM and extended to other dehydration processes aside from the MIVAC," the authors note. It also may be readily implemented for on-line monitoring of automated processes, they added.
However, research results are preliminary, and more study is needed to validate certain assumptions of the process.
Details of this initial work are available in a research bulletin published by the California Agricultural Technology Institute (CATI). It is entitled "A Computation Method to Estimate Moisture Content by Product Weight." Copies are available and may be viewed or requested from the Research Publications page.
For more information on work at VERC, call (559) 278-2089 or visit the VERC World Wide Web site at http://cati.csufresno.edu/verc/.{ page top }