Analytical Session
Yin Li, Malteurop North America Inc, Milwaukee, Wisconsin, 53215
Co-author(s): Mary-Jane Maurice, Malteurop North America Inc., Milwaukee, WI, USA
ABSTRACT: The ASBC color method (Wort-9) has been widely
accepted and used in the malting and brewing industries to determine
wort color and is based on the measurement at a single wavelength (430
nm) using a spectrophotometer. However, this method is time-consuming
and needs clarified wort generated from Congress mash. It is impossible
for satellite laboratories without mashing baths to obtain results.
Therefore, the major challenge is to set up a fast and reliable wort
color assay method without a routine mashing procedure. In this study,
we successfully established a novel and quick method for the measurement
of wort color without Congress mashing based on the simulation of
mashing by microwave technology. Three important factors involved in the
new method, including microwave power, heating time, and grist to water
ratio, have been optimized by a randomized complete block statistical
design (RCBD). The new method is able to obtain a color result within 30
min. The standard deviation of the new method ranged from 2.4 to 2.8%,
suggesting the reproducibility of the new method is very reliable.
Forty-five malt samples were measured by both the novel and Wort-9
methods. The results suggested that the new method showed a good
correlation (r = 0.95) with the ASBC color method, and the
difference between the two methods was less than 10%. We feel the method
would be of interest to maltsters for quickly checking their shipment
samples to brewers and would be useful for those laboratories without
mashing equipment. Microwave mashing also utilizes less expensive
equipment, making it suitable for more laboratories.
Yin Li is a
quality assurance manager at Malteurop North America, Inc. Before
joining Malteurop, Yin was a research assistant professor in the
Department of Plant Sciences at North Dakota State University (NDSU). He
received his Ph.D. degree in fermentation engineering from the School
of Biotechnology at Southern Yangtze University in Wuxi, China, working
on research in the area of malting and brewing, and did his
post-doctoral research work with Paul Schwarz at NDSU. He has published
more than 40 papers in international peer-reviewed journals in malting
and brewing areas, as well as one book chapter, “Malting and Brewing
Uses of Barley.” He is the winner of 2007 AACC International Bruce
Wasserman Young Investigator Award. Yin has served as a reviewer for
more than 10 journals in cereal and food sciences and is an editorial
board member of the Journal of the Institute Brewing.
VIEW PRESENTATION 91
