The efficient use of grains for animal feed requires the use of analytical
methods that can provide rapid indications of the suitability of the grain for
animal nutrition. Ideally, these methods need to be applied at the site of
grain receival within the tight time and cost confines of grain delivery. In
addition, methods are needed in plant breeding to efficiently screen for
target aspects of feed-grain quality to facilitate the development of
genotypes with improved nutritional quality. This review describes a range of
techniques that can fulfil these analytical requirements. These include visual
examination of grain samples for species identification and for recognition of
defects and contaminants. This long-standing approach is rapid, but it is
subjective and dependent on the expertise of the operator. The newer
technology of image analysis offers the prospect of providing similar
information automatically and quantitatively, without the risk of operator
bias. Near-infrared (NIR) analysis is already in general use for grain
analysis at many receival depots in wheat-growing countries, mainly for the
determination of moisture and protein content. There are promising indications
that NIR can be extended to the determination of many other aspects of grain
composition, both the positive aspects that contribute to feed quality, as
well as components such as beta-glucan content that have negative
contributions for non-ruminants. Furthermore, NIR is being developed to
provide a direct indication of metabolisable energy for a range of grain
types. Whereas NIR is primarily suited to the determination of quantitatively
major components of the grain, without the requirement of significant sample
preparation, immunological analyses are appropriate for the determination of
specific and minor components, such as mycotoxins, lectins, alkaloids, and
pesticide residues. These and other methods, suited for on-site analysis,
need to be combined with effective sampling to ensure that the results of
testing are representative of the whole of the grain consignment, and also
integrated into a systematic strategy to ensure cost-effective testing.
Genetic Variation of .BETA.-glucan Contents and .BETA.-glucanase Activities in Barley, and their Relationships to Malting Quality.
