Barley for Food and Health: Science, Technology, and Products

6 Evaluation of Food Product
Quality
INTRODUCTION
Because of the physiochemical properties of β-glucan, inclusion of barley flour
or milling fractions into a baked product can change the quality factors of the
product. It is therefore important to measure and record quality factors, particularly
when using a new or different ingredient. Methods employed by food
scientists to evaluate food quality include both objective and subjective or sensory
(organoleptic) procedures. Methods that can be repeated by an instrument
or a standard procedure, offering an impartial record of results, are considered
objective. They should be reproducible and free of individual opinion or perception.
On the other hand, sensory evaluation depends on human reactions to
food as perceived by the senses of sight, smell, taste, and mouthfeel. Results of
objective and sensory tests of a food should correspond, if they are measuring
the same component of quality. High correlation between an instrumental method
and sensory testing is important in quality control. In this chapter we present a
brief overview on the common procedures employed in evaluating foods that
include barley as an ingredient, such as bread, other baked products, and pasta.
For more detailed information, the reader is referred to Rasper and Walker (2000)
and to the AACC Approved Methods (2000).
OBJECTIVE EVALUATION
Objective methods fall into the categories of chemical, physicochemical, photographic,
microscopic, and physical property evaluation. Chemical methods
include the analysis of nutritive value of foods either before or after cooking, as
well as constituents that affect palatability, such as components that are responsible
for color or flavor. Accurate methods of analysis are critical to nutritional
Barley for Food and Health: Science, Technology, and Products,
By Rosemary K. Newman and C. Walter Newman
Copyright © 2008 John Wiley & Sons, Inc.
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