The boiling water bath method of home canning is recommended for processing high-acid foods. The pH is the measurement of how acidic a food is: Foods with a 4.6 pH or less are considered high-acid, and foods with more than a 4.6 pH are considered low-acid.
Virginia Cooperative Extension
The moisture content variation in fruit dried in I concurrent flow tunnel dehydrators is dependent upon the uniformity of the air flow entering the wet end of the tunnel. Improvements in dehydrator performance were obtained by using a flow diverter and turning vanes to produce a more uniform flow distribution and thereby reduce the moisture content variation. Experiments conducted in prune tunnel dehydrators indicate that the modification can reduce the range in final fruit moisture content by approximately 40%
American Society of Agricultural Engineers