PROCESS FOR CONTROLLING THE GERMINATION OF MALTING BARLEY

Abstract: The present invention relates to controlling germination of barley in the malting process. More particularly, the invention relates to the treatment of malting barley by ionizing radiation prior to the malting process.

Description: PROCESS FOR CONTROLLING THE GERMINATION OF MALTING BARLEY Technical field The present invention relates to controlling germination of barley in the malting process. More particularly, the invention relates to the treatment of malting barley by ionizing radiation. Background art The extension of brewing production is basically limited by the scope of malt production. This step needs extensive appliances and work and is very energy consuming and it is very hard to develop extensively. Thus , world -wide research has been carried out in the field of intensive development in order to save material and energy and to increase capacity. Germination is a physiological process which takes place only under controlled conditions in the presence of sufficient humidity, heat and oxygen. By altering these conditions the biological proce sses may be controlled within certain range s but these ranges are very limited . The metabolism of barley can be influenced by plant hormons , natural and artificial inhibitors, as well as by physical methods . Generally, the materials influencing the development of germ may cause stimulation or inhibition depending on the concentration thereof. Many chemicals were suggested for inhibiting the germination of barley. Kirsop and Pollock, Proc. European Brewery Com. , 8 , 1957 suggests the use of kumarine ; Razga in Soripar, 169 /I96l / dis¬ closes the effect of sodiumazide . Potassiumbromate may also be used according to Macey and Stowell, J . Irist. B rewing, 63, 391 /1957/. Narziss : A sorgyartas , Budape st, 1981 do scrib s the use of nitric acid while Gy, Koilar: Mezogazdasagi Kemia Technolόgiai Tanszek Kδzlemenyek, I960 suggests the use of phenylacetic acid, 2, -dichloro- phenoxy acetic acid or beta-oxy-phenylacetic acid. Among the materials stimulating germination the best known is gibberellic acid which re stilts in an enhanced enzyme induction. This enhanced enzymatic effect cannot be controlled, however, thus the malt having been germinated by the addition of gibberellic acid is liable to dissolve to an extent higher than necessary which can result in enhanced colouring during drying and in an increased malting loss. In order to avoid these unfavourable results combined methods are used, e. g. the unfavourable effects of gibberellic acid are compensated with potas siumbr ornat . The chemical methods have the disadvantage that malt contains residues due to the treatment. It is well known that certain residues have strong influence on the metabolism of plants. These can stimulate or inhibit the develop¬ ment of germ depending on the dose. Kiss et ai. , Sδripar, L to C£ > and 81 to Q3, 1963 have already examined the influence of ionizing rays on the germination of barley. They came to the conclusion that the dose of radiation essentially did not influence the enzymatic system. Disclosure of Invention It has..surprisingly been found that when, irradiating malting barley with a dose of 0,05 to 0,15 kGy germination is inhibited in certain extent and at the same time stimulating effect occures in the enzyme activity. This r sult could not be foreseen as the alfa- amylase activity increases at low dose ranges but this increase in activity is not followed by activation of the peptidjise system. On the other hand, using higher doses results in permanent inhibition of the inductive enzyme system. By using the process according to the invention, both in micro-malting equipment and in industrial scale , hydrolase-rich malt was prepared wherein the over-solution phenomena which occures by using chemical stimulants or stimulating radiation dose s , were eliminated. According to the method of the present invention air -dry, suitably purified malting barley is irradiated with any radiation source known per se , emitting ionizing rays , so that the average dose absorbed should fall within the above range . The barley thus irradiat¬ ed can be used in the common malting process. By using the barley as treated above , the germinating period is shortened to 5 to 6 days from the usual 7 days and the extract yield increased by 0,5 "έ. As mentioned above , the radiation treatment should be inserted in the starting stage of the processing, suitably germination of the treated barley should start within a week from irradiation as the inductive effect of irradiation treatment is declining during storage . The process according to the pre sent invention is illustrated by the following example more in details , without limiting the scope of protection to the specific process as herebelow. E Lmgle_ In the followings the malting process of TRUMF barley stimulated by irradiation treatment is illustrated. Dose optimum of the sort is 0, 1 kGy, tolerance : 0,085 to 0, 115 kGy. Purified and classified air -dry TRUMF malting barley humidity: 11 ,9 %/ was irradiated with ionizing rays so that the absorbed average dose was 0, 1 + 0,015 kGy. The parameters of the raw material used was as follows: Swelling capacity 97,5 % Weight of 1000 grains -40,97 g Protein content 12, 12 % Extract prediction 79,5 % Germinative capacity 97,7 % Germinative energy 96,6 %. The barley thus treated is steeped suitably immediately, but within 6 days the latest. The steeping is performed with cold /10 to 12 C/ water as the irradiated barley absorbs water faster than the control. The steeping period is shortened to 4-8 hours from the usual 54- h ours and during this time the barley absorbs 40 to L2. % of water necessary for germination. The technology of steeping should not be altered, any known steeping method is applicable provided that water is changed in time and the water contains sufficient amount of dissolved oxygen. The use of secondary waters of high temperature declines the stimulation effect. At the end of steeping the roothlet appear at the edge of grain. By using higher steeping temperature /14. C / the same can be ovserved even after 24. to 30 hours . The germination can also be carried out in any useful germinating eqtipment. The barley having been steeped with 40 to 42 % of water content can be germinated to well dissolved green malt within 6 days on floor malting or within 5 days in pneumatic systems . The technology of turning in floor malting is the same as the traditional method, the water content should be kept at 95 % and the air temperature is to be maintained at 10 C. On the 3rd and 4th days strong germinat¬ ion can be observed, at that time should the temperature of the pile raise over 19 C , one more turning is to be inserted in such case . In pneumatic systems the technology of loosening should not be altered; germination is controlled by the temperature of the inflow air. At the start a wetted inflow air of 16 C is used while on the 2nd day the temperature is decreased to 15 C . On the 3rd day strong germination can be observed and the temperature of the pile increases to 19 to 20 C . On the 6th day when using floor malting or on the 5th day when using pneumatic system the green malt is transferred for kilning and dried by methods known per se . Thus, malt having the following para meters is obtained: Irradiated Control Fine extract % 81 ,5 80,9 Raw extract % 79,6 79,0 Difference % 1 , 86 1 ,87 Sacharification minute 10-15 10-15 Final fermentation % 79 , 6 79,5 Diasthetic capacity WKE 194 167 Colour EBC 2,0 2 ,0 Total protein % 11,4 ■ 11 ,3 Dissolved N mg/lOO g dry substance 655 657 Kolbach number % 40, 1 40,0 Lundin fractions A % 23,3 21 ,9 B % 16, 6 16,8 C % 60, 1 61 ,3 Hartong number 5,8 6, 1

Claims: Clai Process for controlling the germination of barley in the malting process, characte rized in that the malting barley which is preferably air dry is treated with a dose of 0,05 to 0,15 kGy of an ionizing ray.

Inventors: BIACS PETER, DEBRECZENY ISTVAN, FARKAS JOZSEF, KISS ISTVAN, KOZMA ISTVANNE, MILTENYI GEZA, PETRO IMRE, RESS PIROSKA, STRAHL ANTAL, BIACS, PETER, DEBRECZENY, ISTVAN, FARKAS, JOZSEF, KISS, ISTVAN, KOZMA, ISTVANNE, MILTENYI, GEZA, PETRO, IMRE, RESS, PIROSKA, STRAHL, ANTAL
Applicants: KOEBANYAI SOERGYAR, KOEZPONTI ELELMISZERIPARI, KOEZPONTI ELELMISZERIPARI KUTATO INTEZET
Application year: 1985
Main classification: C12C1
IPC codes: A01C1, C12C1