« AnteriorContinuar »
compounds are precipitated, causing a hazy appearance in the beer which is not desired, particularly when bottled. It is now claimed, however, that during the process of beer making these insoluble proteids may be changed into soluble proteids if proper conditions are offered, by a peptonizing enzyme which occurs naturally during the process of malting barley. The conditions which favor the development of the enzyme are time and temperature. The longer the growth of the malt and the lower the initial mashing temperature, the more fully will the insoluble proteids be made soluble and the more readily will the remaining insoluble proteids be precipitated by cold storage.
446. Germination.—The maximum, minimum and best temperature of the germination of barley is practically identical with that of wheat . Saunders tested the viability of two varieties of barley during six years as follows: 97; 91; 79; 36; 20; 8.1 Todaro found the germination of barley to decrease in four years from eighty-seven to fifty-eight per cent.2 The vitality of barley is easily injured by heating in stack or bin. In practice, barley that is more than two years old is not considered safe for malting purpose, but its germinating power increases for a few months after threshing, especially if it has not been stacked. A distinction is made between germinative capacity and germinative energy. The former is its capacity to germinate irrespective of time, and should not be below ninety-five per cent; while germinative energy is the ability to germinate within a definite time, and should not be below seventy per cent at the end of two days or ninety per cent at the end of three days at a temperature of 80° F.
447. Species.—There are two well-marked types of barley: (1) six-rowed barley (Hordeum sativum hexastichon Hackel),
1 Can. Expt. Farms Rpt. 1903, p. 44.
• Staz. Sper. Agr. Ital. 31 (1898), No. 6, pp. 525-563. E. S. R. XI, 157.
Six-rowed barley: on the left three single grained spikelets at one joint of the rachis, each with two outer glumes, c. In the spike on the right there are in view only two rows made up of the outer grains, a, of the spikelets upon opposite sides of the rachis. Spikelet, natural size; spike, one-third natural size.
manner as to form one instead of two rows on each side, the type is known as four-rowed barley (H. sat. vulgare Hackel), frequently called bere or bigg in England. In the six-rowed type it not infrequently happens that it is only fourrowed towards the tip of the spike.
T. sat. distichon Hackel). In the ee spikelets each bearing a single grain arranged alternately at ( each joint of the rachis, thus I making a spike with six rows of grains. When the lateral or outside grains of the alternate sets overlap in such a
In the two-rowed type the lateral grains have failed to develop through the abortion of the ovulary, although the stamens may be present. The flowering glume and palea remain in a somewhat rudimentary form, while the outer glumes are fully developed. In the six-rowed type the joints of the rachis are closer together and less in number, making a shorter and much more compact spike than in the two-rowed, but with grains somewhat more numerous. In the two-rowed type the spike is distinctly compressed laterally, while in the six-rowed an end view is somewhat star-shaped. The two-rowed varieties have the greater tendency to tiller.1 There is a hull-less barley (//! nudum L.), also known as naked or bald barley. This type is beardless, and is divided into white, purple and black varieties. There are also beardless varieties among the types third natural which retain the hulls. *'"'
It is probable that all these different types are due to cultivation. Which is the original type appears less clear. Hackel believes that cultivated barley originated from H. spontaneum C. Koch, which resembles closely the two-rowed type.2 On the other hand, it appears that the type most universally cultivated from earliest times has been the six-rowed type; the widespread cultivation of the two-rowed type in Europe being comparatively recent, although of its ancient culture there is no doubt."
448. Two and Six-Rowed Varieties.—At the present time, two-rowed barley is almost universally raised in Europe for the production of malt. When the four or six-rowed barley is raised there it is generally used as food for domestic an mals. The two-rowed varieties appear to be preferred by European malters because of their thin hull and low per cent of protein,
1 Soc. Prom. Agr. Sci., 1899, p. 80.
2 True Grasses, p. 189.
3 De Candolle: Origin of Cultivated Plants, p. 367.
both contributing to a higher per cent of malt extract. In America, the six-rowed barley is grown chiefly, although not exclusively, and is freely used in the production of malt. (445) In a comparative test of two-rowed and six-rowed varieties at the Central Experimental Farms of Canada, the former were from five to twelve days later in maturing. At the five experimental farms of the Dominion the average yield during several years was about the same for both types. At the Central Station at Ottawa, where the conditions correspond to those of Ontario and Quebec, the six-rowed varieties yielded about onefifth more grain.1 Similar results have been obtained on the Ontario Agricultural College Farm at Guelph.* While giving fair returns, the Wisconsin Station found the two-rowed varieties to have frail straw, and, therefore, to lodge badly.8
449. Winter and Spring Varieties.—The two-rowed barley is a spring variety. The six-rowed is both fall and spring sown. Fifty years ago barley was commonly fall sown in Missouri, Kentucky and southern Ohio, but the practice of fall sowing has largely disappeared and spring sowing, usually further north, has taken its place. It is claimed, and it seems probable, that in some instances winter strains were converted into spring strains by spring sowing. Soule states that the Tennessee Station has obtained as good results with fall sown barley as Northern States usually obtain with spring sown. Maryland Station obtained a yield of forty-eight bushels with winter barley and twenty-six bushels with spring barley.4 Very little barley, however, of any sort is raised in the Southern States, and then chiefly for pasturage.
450. Varieties.—There are three types of barley grown in North America known to the trade as quite distinct: viz., Scotch,
1 Can. Expt. Farms Bui. 21, p. 40.
* Ont. Agr. Col. and Expt. Farms Rpt. 1900. * Wis. Rpt. 1903, p. 265.
* MA Bui. 35, p. 191.
Bay Brewing and Chevalier. (473) The use of these terms in trade does not correspond closely to variety types.
Scotch is a six-rowed barley said to have been introduced into Wisconsin from Canada in 1866 by William Buchheit, Waterton, Wis. It has since been largely raised in Wisconsin, Iowa and Minnesota. Bay Brewing or California Bay is a sixrowed variety originally raised in a small district lying south of the Bay of San Francisco, but now more widely distributed in California. Chevalier is a well-known European two-rowed variety said to have been originated in 1819 through selection by the Rev. J. Chevalier, rector of Stoneham, Suffolk, England. Manshury is a standard variety that has been tested and dis-' tributed by the Wisconsin Station.
"This variety originated in Manchuria, China. A scientific traveler in 1859 brought some from Eastern Asia to Germany, and it was grown in the King's garden at Sans Souci with success. Dr. Herman Grunow, Mifflin, Iowa county, Wis., while on a visit to Germany was advised to try some in America, and brought home with him two pounds of the seed. This was sown and compared with about a dozen other varieties and proved much superior to any on trial."1
Oderbrucker, a six-rowed variety imported from Germany by the Ontario Agricultural College, resembles Manshury closely. Among fourteen stations in the United States and Canada which have tested varieties of barley for periods from one to ten years, twelve included Manshury (six-rowed) and eight Chevalier (tworowed) among their recommended list of varieties. No other variety is recommended by four stations.
The yield of grain of hull-less varieties is usually less than varieties bearing hulls, due in part to the absence of the hulls. The straw is weaker and more liable to lodge, thus further reducing the yield harvested. The Ontario Agricultural College, as the result of testing eight varieties of hull-less barley for ten years, recommends Guy Mayle, Black Hull-less and Purple.2 The Arizona Station recommends beardless varieties for hay,
1 Wis. Rpt. 1903, p. 265.
'Ont. Agr. Col. and Expt. Farms Rpt. 1903, p. 133.