Cereal Chem. 73 (4):466-471 |
Determination of Endosperm Characteristics of 38 Corn Hybrids Using the Stenvert Hardness Test.
P. X.-P. Li (1,2), A. K. Hardacre (3), O. H. Campanella (1), and K. J. Kirkpatrick (1). (1) Department of Food Technology, Massey University, New Zealand. (2) Corresponding author. Fax: 06-350-5655. (3) Crop & Food Research Institute, Palmerston North, New Zealand. Accepted March 25, 1996. Copyright 1996 by the American Association of Cereal Chemists, Inc.
Grain hardness characteristics for a range of corn hybrids were measured using a modified Stenvert Hardness Test (SHT). A computer-based data logging and analysis system was constructed to obtain the milling time and transient power consumption during the milling process, from which milling energy and peak power demand were calculated. In addition, the time taken to mill 17 ml of flour (resistance time) and the height of the milled 20-g sample in the collection tube were recorded. The SHT measurements were correlated with the ratio of hard to soft endosperm and the bulk density of the grain. Thirty eight hybrid corn cultivars were tested. It was found that the testing system was simple and easy to use and error variation was low. Results indicate that significant variation in the measured parameters occurred among the hybrids. SHT parameters were highly correlated with the ratio of hard to soft endosperm. Statistical analysis using analysis of variance showed that significant differences occurred among the hybrids for the variables measured. Principal component analysis showed that the milling energy and resistance time were the most effective SHT parameters for assessing grain hardness. Both parameters were highly correlated with the ratio of hard to soft endosperm and the bulk density of the grain. Cluster analysis indicated that endosperm characteristics were genetically controlled and associated with germplasm groups.