DOMINION WHEAT SUPPLY

Taranaki Daily News, 6 August 1932, Page 9 (Supplement)

DOMINION WHEAT SUPPLY

DISAPPOINTING HARVEST RESULTS OF ABNORMAL WEATHER RESEARCH . WORKERS’ PROBLEMS. '(Contributed ’by thri Wheat (Research Institute.) For a iiinnber of seasons past climatic conditions were generally favourable to the production Of good quality Wheat, and the improved growing, milling and baking practices which Were .gradually ■being put into effect as the outcome of the Wheat Research Institute’s inVes= titrations, were beginning to. make themselves felt. The season 1931-32, however, waft characterised by unique Weather conditions, which exerted such profound effects upon the crop that farmers, millers, bakers and the consuming publid found themselves beset With most unsatisfactory problems. These first revealed themselves in the bakehouse, and the consuming public was • soon aware of the fact that the quality of the bread which it was receiving was below that which it was accustomed io get. ' The cause 7 of this trouble could definitely be traced back to the extraordinary weather vagaries which made the 1931-32 wheat season one of the most difficult on record.. It will be recollected that during the spring months of the year reports frequently came to hand of how drought conditions were causing most of the wheat crops in (Mid and South Canterbury to become stunted and barely worth feeding off with sheep. Those crops which were so placed as to maintain reasonable growth were affected by drought conditions, which were accentuated during almost the whole period right up till harvest by a daily .succession of extreme temperatures. In the daytime hob nor’wester®, accompanied by temperature's of SOdeg. and SOdeg., were common, •while the evenings were marked by a ichange of wind, Usually to cold, dry eou’-westers, and temperatures falling almost to frost level. Indeed, in some districts considerable damage was actually done by frost to wheat at the flowering stage. In North Canterbury under such conditions wheat failed to ripen normally. It simply dried off', and was harvested in this ’ state. Trt ’South Canterbury the drought conditions were general, right up to harvest, arid then suddenly gave place to a deluge of rain. The wheat-grower of South Canterbury and Otago carried out his harvesting between constant showers, which resulted in much of the grain sprouting. VARIABLE AND EXTRAORDINARY. Wheat produced in New Zealand, therefore,, in tho 1931-32 crop, had been subjected. to the most "Variable And extraordinary set of weather conditions that could be imagined, and this naturally ‘produced a state Of affairs full of problems for all those who handled it. -The.-season provided A mass of pitfalls, for ■ the miller arid the baker. Established 1 practices of other years would not work on this occasion. The appearance of wheat was entirely deceptive; the flout resulting therefrom perplexed the baker; the quality of the’ •bread suffered. In a season such as this the services of the Wheat Research Institute were of the greatest potential value for guiding those concerned against the anomalies which had Unexpectedly arises. It is unfortunate that some may cite the 'present' Season as indicating that New Zealand, wheat suitable for making good quality bread cannot lie produced, and for reiterating the fact that we should secure our supplies from Australia and Canada, thereby ensuring the Dominion of' high quality bread. .Such an assumption is entirely unwarranted. Everyone will realise that rthe climate of New Zealand is more equable than that of Australia or Canada. < Drought conditions in Australia occur more frequently than they do in our wheat areas, and the same harmful effect.-upon wheat quality- will result there as in parts of Canterbury during the- past season. Canada is similarly ■affected by drought as well as by froftt and -by rust. New: Zealand is not alone in having ■troubles with its Wheat quality, although it stands • high in its utilisation ofs all scientific means to combat them.' The Wheat Research Institute has demonstrated this season that when . recourse was made to its services guid- . ance was afforded, which Obviated the noticeable fall in bread quality that, occurred for a time in the early autumn month's, --An.-improvement in bread quality soon set in, and the problems of the-flour: in bread quality were considerably reduced. In Mid and North Canterbury the autumn' Waft normal, wheat was sown WudOt' good conditions, and tho early part df the growing season was favourable;’ Good rain fell in June; July arid August were dry, as one would desire; there was a good rain in September; October* Arid November were normal; and then drought net in and increased in intensity until the bulk of tho wheat was cut at the end of January. During’ •the last two months, while tho wheat WAS filling and ripening, less than an inch of rain fell. Not only was the rainfall Alight, but What did fall Was of little use because the air was Ao dry that evaporation Was excessive.

ALT,. WHEAT COUNTRY AFFECTED.

Without going intb detail for other districts,, it may bri stated that the general character of the season in many districts north of the Rangitata was more of less thri samfi throughout, although ftomri districts had sufficient pre-harvest rain. In the great Ashburton County, which grows 25 per cent, of all the Wheat in New Zealand, there was in Ashburton itself only 18ins. of rain for the Whole year, instead of the average 28, a<nd in Methven, near the hills, there was also a shortage of 10 inches mostly during the critical months just before harvest. No wheat could maturb properly under such conditions. As a matter of fact, the wheat did not ripen, but- dried off. This was not very evident at the time, and much of the wheat was of good appearance, but the effects of immaturity produced by tho abnormal summer were to show themeelves only too clearly when baking started.

In South Canterbury and North Otago tho ■season was incomparably worse, and, indeed, was the. most disastrous within living memory. There vwas a severe drought in late autumn and winter,- so that the: wheat started badly and /had no reserves of moisture to carry: it over' the spring and suninier, when soil deficient. At Tiraaru there were only 2.58 inches of rain during the four months, April, May, June and July. The spfiiig rainfall was fair, but in Summer it Was dry again, and by Christmas there were to be sefirt thou* sands) of acres of pastures as bate of as if they had just been ploughed. The sUinmer drought, coming on top of the winter drought, spelt ruin to the wield,- Much wheat iieVcr shot, but was fed" Off br htit'for hay, and that which wbA cut was not bnlj low in yield, but

like the Wheat in North Canterbury, did not mature, but merely dried Off. Not content with staging a drought in winter, Nature now staged a flood in harvest. The Timaru figures show 3.82 inches of rain in Eribfilaty instead of the average 1.78; that is, double the normal rainfall during the month when dry conditions arc most desired. But Timaru was mild compared with other areas nearby. In some wheat areas there were 7 inches of rain for the month, and in the hills the enormous total of 17 inches. The stocks got wet through and through. There was no drying wind;, harvest got later arid Inter; the grain sprouted in the stocks, until in some localities the stocks Were as green as grass. In one crop that had been left standing for tho header the wheat actually sprouted, ill the standing ears, Until it looked like a young growing crop, so persistent was the rain and so constant the moisture of the air. DIFFICULTIES OF THE MILLERS. Immature Wheat from North arid MidCanterbury was the wheat that the millers had to deal with when the harvest of 1932 Coriiniericed to i»caeh the mills. While some had matured properly a proportion had dried off instead of ripening, and in South Canterbury considerable quantities of it had not oflly dried off but sprouted. Alth&Ugh millers are used to dealing with all sorts of variations in their wheat, the quantities of immature and sprouted wheats to be handled this year raised a quite exceptional set of circumstances for them to handle. The matter was complicated by the fact that the immature wheat looked good, and when tested 'by all the ordinary millers’ tests appeared quite satisfactory. The drying off was not apparent in the grain, and so dried off immature wheat and properly matured wheat were treated as if they were all, as it wfts believed they were, of high baking quality . The work of the Wheat Research Institute has shown that wheat improves in baking quality the better matured it is. For three years we have had wheat cut at different stages of' maturity in the same field, and have milled and baked the samples from the different cuttings. - ' ' * Wheat in the stock that has been wet, and so continuously, wet as to have sprouted, is always looked on With disfavour by millers. It is likely to have been threshed before it was properly dry, and the dampness may be severe enough to cause the- wheat to go mouldy in the bags, and so be entirely iirifit for milling. Important • changes in the. constitution of the wheat grain take place during fermentation, whereby , part of the starch is changed intd glucose, under the action of a ferment culled diastase, and how fat thrisri changes have taken place, both in the grains that have germinated, arid in those that have nearly germinated under the influence of moisture in the stook, is quite indeterminate, so that the chemical composition of the grain is iio longer known. Wheat is a living substance until it passes between the flour mill rolls, and its chemical composition alters from month to month in the miller’s Store. Under normal conditions, these changes can be foretold and allowed for, but (ftlie changes that take place in sprouted wheat are much less certain, and so the miller runs a considerable risk when he handles sprouted wheat at all.

PRACTICE OF BLENDING WHEAT.

In most seasons, trouble with reference to quality Of wheat from one district, can be adjusted by purchases of wheat from another district and this adjustment is the millers’ standard practice. In the past season the peculiar and quite extraordinary position arose that there were troubles With wheat from the northern area, and troubles bf an entirely different nature in the southern area, and neither of these could 'be completely remedied by the ordinary blending processes. Each difficulty therefore had to be studied and remedied as if it stood alone. When the millers found that the Wheats weie not giving flours as good as the appearance of the wheat promised, the first step whs to buy more wheat from districts famous for high quality to blend with the unsatisfactory Wheat already in their stores. But it was found that even this wheat did not give tho expected results. Millers then turned to the Wheat Research Institute for Special help . beyond what they Usually obtained. Samples of wheat poured in by the hundred. The Institute’s miller could not cope with them, sb the flour millers supplied Un extra miller in order that the experimental mill might run double shifts. Each wheat, as it was ground into flour, was baked in the experimental oven, a Score given tri the loaf, rind the miller 1 advisrid of the result. Thus the properly matured wheat was separated from that which had dried off, and the miller was enabled to use his stocks to tho 'best advantage, gradualy using up the unsatisfactory wheats by blending them with the strongest, in such 0. Way aS to secure all the year through a product of standard quality. By this means the difficulty with flour produced early in the year as a result of the abnormally dry ripening season, has largely been eliminated from the mill products.

With the sprouted wheats the position Was almost the reverse. The .wheat was sent to the Wheat Research Institute to mill and bake, and the result in the case of about 60 per cent, of the samples was that, provided they were used in no greater proportion that about 10 per cent, of the samples, they would produce no ill effect, but would actually improve the quality of the resultant flour. Samples representing 150,000 bushels of sprouted wheat were received, and of these between 80,000 and 90,000 bushels were, on the institute's advice, accepted by millers, and so disposed 6f by farmers at prices better than had hefili expected. To redeem this quantity of good grain from stock feed to human use Was clearly ft. benefit to tho Country at large.

VALUE OF MALTED WHEAT. The mere blending of wheats, however, docs not suffice to remove all the effects of drying off without maturing, although it prevents those effects from occurring spasmodically io the detri* ment of the baker and the consumer. Immature wheat is low in a special forment that produces food for the yeast, and therefore the bread baked from such wheat docs not riso as it should, and has not the desired texture and flavour. If, however, some wheat that has been placed under special conditions of moisture and temperature to allow Hie rich development of this ferment—malted wheat, in fact—is added to normal wheat low in the ferment, thb deficiency is entirely removed. Malted i Wheat prepared Under the guidance of tho institute is now being manufacture cd on a commercial scale, and wlieit it is mixed in the proportion of 1 p6f cent, with unprepared wheat it girds in Very many cases an extraordinary improvement. The change irt tlte loaf caused by the addition 6f 1 per cent, of malted Wheat has to be seen to he believed, and its use has to a large extent over* come the difficulties in the production of a good loaf from the Wheat harvested under the late abnormal dry weather conditions.

Although droughts during the critical filling and ripening period of the wheat

lire not likely frequently to recur With tho intensity experienced last season, yet many areas here, as in other parts of. the world, suffer from some degree of deficiency of pre-harvest rainfalls. To guard against loss of yield from this cause the farmer adopts two practices. First, ho manures with sUpef-phosphate, which has the effect of allowing the wheat to make better use of the water that there is available; second, he ploughs as early as possible so as to conserve for summer use the rainfall of Winter and spring. It is now apparent that these practices, insofar as they prevent the drying off of wheat while It is still immature, not only increase the yield but improve the quality, and so do good to the country in that they discourage the importation of Canadian flour by making our own good enough for all bakers’ purposes. Tho experiences of this abnormal season have given the institute an op* portunity of showing that the temporary defects in bread quality Were only the effects Of an UnUsual season, and were m?t inherent in New Zealand wheats more than in wheats from other parts of tho world. The season has increased our knowledge of tile re-action of wheat to different climatic conditions, and may well bear fruit in permanently raising the standard of New Zealand wheat and its products.