Special Chemist (Cereals), NSW Agriculture, Agricultural Research Institute. Wagga Wagga
Research into the functions, uses and characteristics of the components of cereals, particularly wheat, has been disproportionately concentrated on the protein fractions. And, of course, barley and oats do contain proteins worthy of attention, although they are functionally less important than those of wheat because they are not gluten-forming. However, more importantly, the coarse grains (barley and oats) offer relatively unstudied areas for research into starch and oil characteristics as well as the relatively new bandwagon of the B-glucans (for lowering blood cholesterol).
The starch of barleys has a much wider range of characteristics than those of wheat. For example, a waxy barley starch with which a liquifying enzyme was intimately associated and a barley with a fragmented starch granule have been described by DeHaas et al. (1978, 1983). Could these have commercial uses? Many chemically or enzymically modified starches are manufactured for specific food end-uses. Given the move towards more "natural" foods, the isolation of starches with particular end-uses from barley, oats or other cereals must offer an advantage over those "manufactured" and "mucked-about-with" in nasty factories. Naturally-occurring starches which behave as the food processor desires must be more acceptable than chemically modified ones to a rapidly increasing number of consumers.
May I remind you that a recently developed breakfast cereal was comparatively unsuccessful because it contained triticale, which many thought was a chemical, not a man-made cereal. Please consider the effect on the scientifically illiterate when they find out that epichlorhydrin is used to chemically modify starches. The very sound of the word is worrying to the non-chemist (and scares the bejeezus out of me).
Barley, contrary to popular (i.e. advertisement-generated) belief, contains more B-glucan than oats, and that B-glucan is more evenly and usefully distributed through the endosperm rather than being concentrated in the bran fraction as in oats. Thus barley flour contains almost as much B-glucan as the whole grain, whereas oat flour contains less than 20% of that of the intact grain.
However, barley is not extensively used as a human food, and has not received the promotion which oats has enjoyed. It is interesting to note that Kelloggs Balance contains as much barley as oats and yet it is the oats that get the credit. A recent article in a popular magazine on how good oat B-glucan was for your health was illustrated with a photo of a waving field of ..... yes, barley.
Generally speaking, if I were to attempt to get more B-glucan into the human diet, I would start with barley rather than oats. An idea of the range of possible products can be gained from the proceedings of the workshop on Alternative End Uses of Barley by Sparrow et al. (1989). They include breads and noodles as well as the more conventional uses.
Cultivars of barley, or oats, with high levels of B-glucan can easily be selected. Rapid screening of thousands of lines in early generations using NearInfraRed Reflectance Spectrophotometry (NIRS) followed by more accurate selection using a commercially available method (McCleary and Glennie Holmes, 1985) will quickly identify high B-glucan containing cultivars. But there is no point in the breeding and selection of specific-use cereals unless there is a value-added market to justify their existence. Someone has to want to pay for them: this requires the development of new foods and their promotion.
Oats have interesting starches, very interesting lipids and, of course, boring B-glucans (they're the same as those in barley).
Although the range of starches in oats is narrower than that in barleys, there are sufficient differences to warrant research into new food related uses.
Similarly, the lipids of oats offer a natural source of antioxidants: there is already a commercial product called Avenol made from oat oil whose time may just have come. This again must be more acceptable to the consumer than butylated hydroxyanisole or butylated hydroxytoluene. (Anisole sounds terrible, and doesn't toluene cause cancer?). We can no longer dismiss these feelings: no matter how absurd and unjustified some scientists think they may be. The oil content of oats can be genetically manipulated, and selection of high lipid-containing oats would be relatively simple with the techniques already available at the ARI.
Again, as with barley, oat cultivars can be selected with high levels of B-glucan, as long as there is a value-added market available. The trouble with oat B-glucans is that they are associated with the bran, and bran is what cereal processors have been removing from milled grains for centuries. People, in general, don't like bran. It's scratchy, bulky and requires mastication before it can be swallowed. This limits the proportion which can be added to mass-appeal foods.
Finally, there are extraordinary opportunities offered by the development of hulless or "naked" barleys and oats. The development of new food uses based on these types of grain requires considerable research. Remember, again, that we cannot commit resources to the breeding and selection of hulless barley or oats unless you demonstrate a niche market for them.
But Why Carry Out The Research Into These Opportunities In The Riverina?
Firstly, and most importantly, because this is where the cultivars are. Many papers published on the chemistry, structure and function of the components of cereals proceed from the premise that barley is barley, oats are oats, and wheat is wheat. Researchers obtain a tonne of a cereal, treat it in certain ways, and publish the results as definitive. Many conclusions just ain't true: in opposition to the conclusions in many papers I can provide a cultivar which will behave differently to the one which was examined: often sufficiently differently to negate any commercial conclusions. This is particularly so with barley and oats, for food processors are much more aware of the effect of cultivars in wheat processing, having for years had to deal with hard and soft, high and low protein, bread, biscuit and pasta types.
Secondly, the experience of this Department has proved conclusively that collaboration between plant breeders and quality chemists only works when they are physically close together. Despite the wonders of the fax, of electronic mail and the phone, nothing replaces being able to wander down the corridor for a chat. We can't move to a capital city, for we need land to grow our plants, so you had better come to us.
As I have attempted to emphasise in this talk, value-added uses for cereals with specific characteristics must be demonstrated before the long-term process of breeding and selection is justified. There is no point in us going to industry with, say, a new high B-glucan grain if (i) industry has no food line to put it in; and (ii) they won't pay anything extra for it. Only you can develop these new or modified foods which then the industry has to be persuaded to manufacture.
Thirdly, because the cereal chemists at the Institute have some equipment: about a million dollars worth. We routinely use GC, HPLC and NIRS, Fibretec and Kjeltec apparatus as well as enzymic and conventional chemical analytical techniques. We can mill wheats, physically test doughs, and bake breads, conventional, flat and steamed, and make biscuits. We can malt and mash barleys. We can identify and measure fatty acids in oils, goitrogenic glucosinolates in Brassicas and volatile acids and soluble sugars in foods, feeds and silage. And we can do all this on very small samples: complete milling/baking or malting/mashing tests are routinely carried out on 100 g of grain. Starches can be characterised by thermoviscometry on 5 g samples.
This means detailed studies require only small quantities of grain, and thus more than one cultivar can be examined. And we're also pretty fast - John's team test eight to nine thousand samples per year, we test about five thousand.
Fourthly, because we, John Oliver and I, want you to come. Because we want to collaborate with those who work on the varieties which we release. I have three collaborations going with CSIRO at the moment: one on the effects of high temperature insect disinfestation on the quality of barley, another on predicting malting quality by NIRS, and a third on the effect of storage conditions on viability and malting quality. Two of these are with CSIRO staff in Sydney and one in Melbourne: why don't you all come to Wagga?
4. Sparrow, D.B.H., Lance, R.C.M. and Henry, R.J. (1989). Alternative End Uses of Barley. Proceedings of a Workshop held at the Waite Agricultural Research Institute, September 1988. Published by the Cereal Chemistry Division of the Royal Australian Chemical Institute, Clunies Ross House, Parkville, Vic.