Comparison of methodologies for determination total humidity in two types of Andean corn (Zea mays L.)

Corn is one of the most consumed crops nationwide, where consumption and production increasing constantly. The development improved varieties have been an arduous work for the National Institute of Agricultural Research (INIAP-Ecuador), where two varieties stand out from the rest; soft maize (INIAP-122) and the semi hard maize (INIAP-180). These varieties present higher production yield, and tolerance to pests and diseases. Humidity of the grain is a key factor, because it closely related to the storage, processing and marketing of the product. The objective of the research is to evaluate the different moisture methods and their principles. For this research, 7 lots of grain humidity were elaborated (10%, 11%, 12%, 13%, 14%, 15%, 16%). After this, a homogeneity test was carried out, in which a statistical analysis was applied in order to evaluate the degree of homogeneity within each of the lots. Moisture was measured applying methods a) ISO 6540:2013 method (oven), b) AACC 44-15A method (oven), c) rapid method as Agratronix MT-16 (electric-capacitance), d) Infrared method (thermogravimetric) and e) INIAP method (electric-impedance). All lots of soft and semi hard corn (10-16%) were homogenous before comparison test. There was significant difference between moisture methods tested in both varieties.