Kiyama, Ryo

Kinoshita, Hideo

Fritsch, R.

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Title Degradation of starch by high pressure jetAuthor(s)Kiyama, Ryo; Kinoshita, HideoCitationThe Review of Physical Chemistry of Japan (1952), 22(1): 18-21Issue Date1952URL http://hdl.handle.net/2433/46675RightType Departmental Bulletin PaperTextversionpublisherKyoto UniversityThe Review of Physical Chemistry of Japan Vol. 22 No. 1 (1952)    DEGRADATION OF STARCH BY HIGH PRESSURE JET.                        by Rv~~ Krvaat,r and HInF.n Krxnsnn~.r."                                 Introduction.    It has been reported that it is possible to. shatter the liquid"'•'"-' and to decrease the molecular weight of polyethylene"' by the way of high pressure jet. For the purpose of confirming the phenomenon of the degradation of the molecrde of poly-mer, the authors experimented with an aqueous solution of the amylose extracted from starch and confirmed the decrease of the molecular weight by measuring viscosity and reducing power. And moreover, they experimented with inuline-chain structure as amylose-, maltose, lactose acrd sucrose, and studied the effect of high pressure jet on the degradation of molecule.                          Apparatus and Experimental.    The apparatus used are all the same as in the case of the previous paper,"' the pressures being 2000 and 4000 atm, the nozzle diameter 0.50 mm, the distance between the nozzle and the crashing plate 10 mm, and the maximum number of jetting 35 times.                                   Samples.    Potato starch of the Japanese pharmacopoeia is purified by the following method, namely, the proteins in starch are extracted by stirring in a 0.2 ~ NaOH solution for about 50 hours, and the fats are extracted with methanol for 10 hours by means of a Soxlet extractor. For the purpose of obtaining the uniform size of amylose molecule, after pre-treating the starch for half an hour with hot water of SG° C, the starch was separated by centrifuging, and then stirring it for 1 hour with hot water of 61` C, the extracted aqueous solution of amylose was separated by centrifuging. The molecular weight of amylose was about 50,000. When the temperatures of pre-treating and extracting were 6G°C aad 65°C respective]y, the moleculaz weight of amylose was found to be about 100,000. Commercial inuline, maltose, lactose and sucrose were used.                             Experimental Results.    As the method of measuring the molecular weight, they used the way of vis-cosity and used the equation of Staudinger lim r„°Jc=Km x M. Iampitt, Fuller                                                                                     r~-.n    s Saikyo University.     (1) R. Kiyama, H. Kinoshiia and K. Suzuki. This journal, 21, 82 (1911)     (2) R. Kiyama, H. Kinoshita and K. Suzuki. ibid., 22, 4G (195'L)     (3) R. Kiyama and H. Kinoshita, ibid., 22, 1 (1952)The Review of Physical Chemistry of Japan Vol. 22 No.                      Degradation of Starch by High Pressure Jet 19 and Goldenberg"' used 4 x 10-', and Samec and his coworkers"10' 1.0 x 10"' for the K„ value of a aqueous solution of amylose. The authors determined the K„ value of aqueous solution by using the relation of the intrinsic viscosity of a IN-KOH solution of amylose arid the osmotic pressure measured by I. A. Nolff, L. J. Gundrum and C. E. Hist"' (For the molecular weights of 130,000 and 64,000, the intrinsic viscosities of a 1N-KOH solution of amylose arc 1.41 and 0.57 respectively). It is clear that the value of K> depends on the shape of molecule, and moreover it may depend on the distribution of molecule. In the present experiment the greater the degree of the inclination of the straight lines of viscosity and concentration, the smaller the value of K,,,. Accordingly, for the calculation of the molecular weight they used the value of 0.73 ^ • 0.93 x 10-', corresponding to the inclination of that straight line. The method of Hanes'"' is used for measuring the reducing power, namely, the solu-tion of K-ferrityanide and •the reducing agent are warmed in a water bath. Ferric                                Table 1.1 (1952)EXP- No.Press. (a[m)Cone (3~)Number of ii  letting2000 0.900 s itMolecular  weight  Uegree of pnlymferiza[ion.,sssoo c~toosu; 391 3s9'L000 ~ OSi3~I 'L0000.73U 9 ll;377 3570 35siz 30f4 40005   4000o~ 0.730 9 if+3;a 238 2200 2df 149Tablc 2.Exp. Na(i~~. ca~~anonCones (3b)o.~~\o. of jetting0 1 z 3 10 201\Inlecula Degree nr~ I weight ~ ~zahonn s~Reducing power98200 (+0000 51100 96600 39000 3.1800(Of, 370 31(+ 288 241 2211.30 1.831 2.'Ll 3,(y~~ 3.48'img alucox/gml incre~ed4.13 5.(i8 0.44 7S1 10.00 12 391.55 2.31 3.41 587 8.26                                                            n '"'  s*: number of ond split, calculated from equation 5=2 -l) where n isP       the initial degree of polymerization. (4) L. H. Lampitt, C. li. F. Fuller and N. Goldenberg, J. Soc. Cl:em. 6rd. 67, 41 (1943) (5) Samec and Dalar, Z. Pkysik. Chem., 259, 204 (1939) (0) Samec and Rakusa, ibid., 263, 17 (1940) (7) I. A. wolff, L. J. Gundrum and C. E. Rist, J. Ames. Ckru+. Soc., TL, 5188 (1950) (87 C. S. Hanes, Biocfrent. J., 23, 99 (1929) (9) 1~ Osugi, P~ae. Japmr Arndenev, 27, 2I1 (1931) Ko. 5.    W. H. Durfec and %. I. Keaesz, J. Amer. Ckenr. Soc., f•2, 1196 (19•A)I iIIiThe Review of Physical Chemistry of Japan Vol. 22 No. 1 (1952)in. goo 0 '~ sao ~~ soo ~~300wN v 200 U Q ~~i_n to 6t.,,,R Kiyama and            5 10 1~                Number of jetting. Pig. 1 Relation between degrees of polymerizatio                and number of jetting.destruction and it was effective to make distance between the nozzle and the eras the solution of amylose, the same effects results of Table 1 the molecular weight namely the speed is higher.   (2) As the temperatures of water in e and 65°C, the molecular weights are 50,000 of decreasing the molecular weight is set smaller. This result is coincident with the nishes when the jetting is repeated over 1 that there is a limit to the size of the mole For the purpose of recognizing this fack they of inuline is a chain like that of amylose The viscosity and the reducing power are 43S solutions. As to the dieter, they expe maltose, lactose and sucrose, and confirm power that the dieter is not destroyed by je conditions used, the molecular weight of 10 of molecule, but such samples aze not in    (3) The inclination of the straight line concentration, approaches to the horizontal eq number of jetting.    (4) The relation of the number of bond split of amylose to the increase of reducing power is shown in Fig. 2. The fact that there holds no straight relation shows that the way of destruction is not at random, but is paztially due to the distribution of the degraded sample. As described formerly, in this experiment, it is anticipated that it will be difficult to degrade the smaller molecule from theH. Kinoshita     ion is reduced to ferrous ion and a     solution of KI is added. The deposit--   ted iodine which is oxidized by resi-   dual ferric ion is titrated with Na-   thiosulphate. The experimental resu-   lts and conditions are given in Tabl• o- es 1 and 2 and Fig. 1.              Considerakions,- (1) In the case of decreasing the    molecular weight of polyethylene, n the mechanism of destnuction was     considered as a kind of mechanical the pressure higher and to make the hmg plate shorter. In the case of jetting are expected, and from the experimental is smaller, as the pressure is higlrcr, xtracting amylose from starch are 61°C and 100,00() respectively. And the rate alley, as the initial molecular weight is fact that the effect of the jetting dimi-0 times. Accordingly, it is anticipated tale destroyed in the present experimenk experimented with inuline. The structure and its moleculaz weight is about 5000. unchangeable after the jetting of 19e and rimented with various concentrations of ed from the measurement of the reducing ttiag. Consequently, in the experimental ,000-20,000 may be the limit of the size hand. indicated by the relation of viscosity to line in cons uence of the increase of theThe Review of Physical Chemistry of Japan Vol. 22 No. 1 (1952)                      Degradation of Starch by }Iigh Pressure Jet 21 reason that the limit of molecular size corresponding to the experimental conditions exists. Therefore, it is impossible to consider = 4 8 that the way of destruction is at random. ~                                                  ~3 When the molecular weight is smaller, it is a capable to prepare the samples of uniforni o                                                  Y 2molecules, but it is difficult to obtain the .`S E quantity enough to use for this experiment. z 1    (5) As to the mechanism of the degra-dation of amylose molecule, they thought 2 4 6 8 10 it mechanical, but anticipated the effects of Increased reducing power. temperature and oxygen. When the room Fig. 'L Relatimr between increased temperature is 20° C, the temperature of the reducing power and number of                                                  bond split. crashing plate is 32.5`C after the jetting of 20 times under a pressure of 4000 aim. 'Therefore, the effect of temperature is negligible. In wmparison of the sample experimented in the air with that in the stream of argon, there exists no difference bchveen them, and so the effect of oxygen is also negligible.    The authors are indebted to t}te Department of Education for the Grant to the Cooperative Research (The Fundamental Research on High Pressure Industries)-                               Tke Laboratory of P&ysical Chemistry,               ' Kyolo University.i

Degradation of starch by high pressure jet

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Degradation of starch by high pressure jet

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