water content systems at maximum compaction. It follows that even material at the base of the compact experienced a suffi- ciently high stress t o deform plastically and hence a value of D approaching unity was possible. Removal of the applied stress left permanently deformed granules although there was a variability between granules which may be attributed to the complex stress distribution in the compact and inhomogeneities between and within the granules themselves. Two classical approaches to the prediction of transmitted pressure in compaction are those of Shaxby and Evans [13] and Spencer et al. [16]. The former predicts that the pressure transmission ratio. pT/pA. will increase with decreasing height of the compact (equation 3) and the latter that this ratio will increase with decreasing initial height of the compact (prior to compaction). Previous studies with polymer powders [ 171, potato granules [18] and sucrose and sodium chloride [19] have shown the pressure ratio to be relatively insensitive to the changing height during compaction. The results for potato starch are inconclusive. The pressure transmission behaviour of the low water content glassy potato starch is distinct from the response when it is in a rubbery state (Fig. 5) . Isherwood and Katwiremu [17] commented that the Spencer e t al. analysis is more likely to apply for compressible materials and the data of Fig. 5 show some limited support in that regions of constant pressure ratio are more pronounced for high water contents.

The water content maximum found after compaction (25% w/w) is less than the maximum amount of water capable of sorbing into the granules (27.5-28.0% w/w) [2]. The stress and strain of compaction is causing migration of the water out of the material. Wherever the water is sited, i. e. in the amorphous or crystalline regions within the granules or in the interstices between the granules, its mobility is such that it can move out of the compaction cell during the time span of the experiment (typically 150s).

Bibliography

[ 11 Lrvine, H . , and L. Slade: Water as a plasticizer: physic0 - chemical aspects of low-moisture polymeric systems. in: Water Science Reviews. vol. 3, Ed. F. Franks. Cambridge University Press, Cambridge 1988, pp. 79-185.

[2] Hoine, V . , H . Eizot. and A. Buleon: Reinvestigation of the potato starch volume during the sorption process. Carb. Polym. 5 (1983,

[3] Ollerr. A.-L.. R. Parker, and A. C. Smith: Deformation and fracture behaviour of wheat starch plasticized with glucose and water. J.

91 - 106.

Mater. Sci. 26 (1991). 1351-1356 and erratum 26 (19) (1991). iii.

[4] Shen, M. C., and A . Eisenberg: Glass transitions in polymers. Solid State Chem. 3 (1966), 407-481.

[5] Zeleznak, K. J. , and R. C. Hoseney: The glass transition in starch. Cereal Chem. 63 (1987), 121-124.

[6] Paronen, P., and M. Juslin: Compressional characteristics of four starches. J. Pharm. Pharmacol. 35 (1983). 627-635.

[7] Mercier, C., R. CharbonniPre, and A . Guilbor: Influence d’un traitement par pression sur la structure granulaire de differents amidons et sur leur sensibilite aux enzymes. Starch/Starke 20

[8] Gerrirsen, A. H., and R. Dekker: The unconfined yield strength of potato starch: the influence of consolidation stress. time and temperature. Powder Tech. 34 (1983), 203-21 1.

[9] Heckel, R. W.: Density - pressure relationships in powder com- paction. Trans. Metall. SOC. A. I. M. E. 221 (1961). 671 -675.

[lo] Heckel, R. W.: An analysis of powder compaction phenomena. Trans. Metall. SOC. A. I. M. E. 221 (1961). 1001 -1008.

(111 Roberts, R. J. , and R. C. Rowe: The compaction of pharmaceutical and other model materials - a pragmatic approach. Chem. Eng. Sci. 42 (1987), 903-911.

[12] Gerritsen, A. H., and S. Stemerding: Crackling of powdered mate- rials during moderate compression. Powder Tech. 27 (1980).

[13] Shaxby,J. H., and J. C. Evans:The variation of pressure with depth in columns of powders. Trans. Faraday SOC. 19 (1923), 60-72.

[ 141 Sears, J. K., and J. R. Darby: The technology of plasticizers. Wiley, New York 1982.

[lS] Rees, J. R., and P. J. Rue: Time-dependent deformation of some direct compression excipients. J. Pharm. Pharmac. 30 (1978),

[16] Spencer, R. S., G. D. Gilmore, and R. M . Wiley: Behavior of granulated polymers under pressure. J. Appl Phys. 21 (1950).

[17] Isherwood, D. P., andJ. B. Katwiremu: Effect of die wall friction on the compaction of polymer particles. Plast. Rubb. Proc. Appl. 2

[18] Ferdinand, J. M., A . R. Kirby, and A. C. Smith: The compaction properties of dehydrated potato. J. Food Proc. Eng. 12 (1990).

[19] Ollett, A.-L., A. R. Kirby, R. Parker, and A . C. Smith: A comparati- ve study of the effects of water content on the compaction behaviour of some food materials. Powder Tech. In press.

(1968). 6-11.

183 - 188.

601 -607.

527 -531.

(1982), 253-263.

99-112.

Address of authors: A,-L. Ollert, A. R. Kirby, S. A . Clark, Dr. R. Parker and Dr. A. C. Smirh, AFRC Institute of Food Research, Norwich Laboratory, Colney Lane, Norwich, NR7 4UA (Great Britain).

(Received: May 27, 1992).

Chemical Modification, Cross-Linking and Characterization of Some Starch Hydrogels

Y. A. Aggour, Mansoura (Egypt)

Modified starch hydrogels were prepared via the reaction of starch with acrylamide ( AAm), under certain conditions and cross-linking with N,N’-methylenebisacrylamide (MBAAm). Rheological measure- ments of different ratios gels shows that both increasing of cross-link- er or substrate concentration, lead to increase the elasticity of the gels. The molecular weight between two entangelement points (Me), was calculated from plateau modulus (G,,) values. The effectiveness of the cross-linker was calculated by comparison between the number of elastically effective points rheologically [n,(r)] and that obtained from theoretical values [n,(t)]. The effectiveness has a maximum

Chernische Modfizierung, Vemetzung und Charakterisierung einiger SWrke-Hydrogele. Uber die Reaktion von Starke mit Acryl- amid (AAm) unter bestimmten Bedingungen und Vernetzung mit N,N’-Methylenbisacrylamid (MBAAm) wurden Starke-Hydrogele hergestellt. Rheologische Messungen in verschiedenen Verhlltnissen zeigen. daB sowohl die Zunahme des Vernetzers als auch der Sub- stratkonzentration zu einer Erhohung der Elastizitat der Gele fuhren. Das Molekulargewicht zwischen zwei venvirrten Punkten (Me) wurde aus Ebenen-Modulen errechnet (Gpf). Die Wirksamkeit des Vernet- zers wurde durch Vergleich zwischen der Anzahl von elastisch wirk-

Ftdrchistarke 45 (1993 Nr. 2. S . 55-59 0 VCH Verlagsgesellschaft mbH. D-6940 Weinhelm. 1993 0038-9056/93/0202-0055$03.50+.25/0 55

value 5.76% at the higher substrate concentration of 25% (w/w) gels. samen Punkten rheologisch (n,(r)) und den aus theoretischen Werten Swelling of different gels were studied in pure water and in different (n(t)) errechnet. Die Wirksamkeit hatte einen Maximalwert von salt solutions. The curves show shrinking of the gels, however no 5,76% bei der haheren Substratkonzentration von 25% (w/w)-Gelen. collapsing occurs with increasing the concentration of salts. The maxi- Die Quellung der verschiedenen Gele wurde in reinem Wasser und in mum water absorption capacity were 140 g/g for 15/3 gels. The struc- unterschiedlichen Salzlosungen untersucht. Die Kurven zeigen ture of the gels were interpreted with the guide of 13C NMR spectro- Schrumpfung der Gele, jedoch tritt mit zunehmender Salzkonzentra- metry. tion kein Zusammenbrechen auf. Die maximale Wasserabsorptions-

Kapazitat betrug 140 g/g bei 15/3-Gelen. Die Struktur der Gele wurde mit Hilfe der '3C-NMR-Spektrometrie interpretiert.

20-13 120 t PI v 2513 I

1 Introduction

A gel is a cross-linked polymer network, swollen in a liquid medium. Its properties depend strongly on the interaction of these two components. The liquid revents the polymer network from collapsing into a compact mass, and the network, in turn, retain the liquid. Extensive studies have been exported on the altering of structure and properties of polysaccharids by chemi- cal modifications, e. g. acetylation, cross-linking and cyanoethy- lation [l-41. Grafting of polysaccharides in a two phase system is a common method due to limited solubility of the naturally occuring polysaccharides. The graft copolymerisation of starch with vinyl monomers has been extensively investigated [5-71. Starch-grafted polyacrylamide copolymers have been used as flocculants and adhesive agents [S]. Investigation of the graft- copolymerization of AAm onto starch and studies of the kinetics of the starch have been done [9-111. The rheological properties of starch gels can be controlled by chemical modifi- cation. More information about the viscoelastic behaviour and the structure of gels can be obtained by using non-destructive rheological measurements [12]. In this study the modification of starch had been done by the reaction of starch with AAm in alkaline medium, and cross-linking by N,N'-methylenebisacryl- amide at 50°C in water bath. Swelling and rheological properties of these modified gels were carried out using different ratios of substrate and cross-linker concentrations. NMR spectroscopic analysis were used to explain the structure of the gels.

. 2 Experimental 2.1 Materials

Native maize starch in pure state were provided by Cerestar company. Acrylamide, N,N'-methylenebisacrylamide, NaOH, NaCI, CaCI2 . 2H20 and AI(N03)3 .9H20 were of laboratory grade (Merck).

2.2 Preparation of the modified gels

The gels were prepared in a homogeneous geometrical form by dissol- ving the required amount of starch in IM NaOH (sodium hydroxide catalyzed the reaction and hydrolyzed the amide groups), followed by addition of acrylamide solutions. The cross-linker was added while stirring the reaction solution which was then left to stand at 50°C for approx. 2 h before being kept overnight at room temperature to reach complete gelation. The gels were washed three times with pure water to remove any excess of unreacted reagents, before swelling measure- ments.

2.3 Rheological and swelling measurements

P31.

2.4 NMR Analysis

A full description of the method can be found in previous paper

The 13C NMR measurements of the gels were carried out in D20, H20 at 20°C in a Bruker MSL 300 spectrometer at 75.47 MHz. The pulse Fourier transfer technique was used with complete proton decoup- ling.

3 Results and Discussion

3.1 Swelling measurements

3.1.1 Influence of substrate concentration

Figure 1 shows the swelling behaviour of starch-acrylamide- N,N'-methylenebisacrylamide gels [St-AAm-MBAAm] with different percentages of substrate in A1(N03), solutions of different concentrations. Shringking of the different gels occure until 5 X 10-2M salt solutions then the swelling capacity in- crease, reach to a maximum in pure water. The order of swelling are 15/3> 17.5/3> 20/3> 25/3. The explanation of this may be due to the factor which increase of liquor ratio of the gels

o 1513 X 17.5/3

c mol,l-'

Fig. 1. St-AAm-MBAAm gels in A1 (NO&.

Influence of different substrate concentration on the swelling of

increase the carbamoylethylation reaction, and also increase the hydrolysis of the amide groups to give ionic gels [ll].

3.1.2 Influence of cross-linker concentration

Figure 2 indicates the influence of MBAAm concentration on the swelling of 15 wt% gels in CaClz solutions. As it is clear from the figure increasing of cross-linker concentration lead to decline the swelling capacity, this can be attributed to increase of the crosslinked points and decrease the size of mesh width within the gels. Also the chance of the hydrolysis of amide groups decreased, hence the ionic character of the gel decreas- ed, and its swelling properties [15]. Figure 3 illustrates the influence of both the substrate and the cross-linker concentrations on the swelling capacity of gels in the pure water. Increasing both the cross-linker or substrate concentrations leads to decrease the swelling values for the same reasons which are mentioned above.

starchlstarke 45 (1993) Nr. 2, S. 55-59 56

15/03 0 15/05

15/10 0 15/15

3.6

3.4

3.2

3.0-

a 5 2.8-

*p 2.6- CTI 0

2.4-

2.2

c C ~ U Z m01. r1 Fig. 2. Effect of cross-linker concentration on the swelling of gels (IS wt YO) in CaCI? solutions.

-

-

-

- 2o t

I I I

0 5 10 15 20 25 3

Fig. 3. Effect of both the cross-linker and the substrate concentrations on the swelling of different gels in pure water. 0-0 variation of the cross-linker (mol%). X-X variation of the substrate (wt%).

3.1.3 Influence of different salt solution

Figure 4 shows the effect of different salt solutions on the swelling of 1513 gels. The swelling capacity decrease by increase the concentrations of Na', Ca2+ and A13+ solutions. However, slight increase in swelling were observed at higher salt concen- tration due to reverse of polarity onto the backbone of starch [14,16]. Shrinking of gels continues up to l O P 3 ~ concentration, however no collapsing of the gel occures, in contrast to hydro- lysed polyacrylamide gels [16], which suffered from a complete collapse in AI(NO& solutions.

3.2 Rheological measurements

3.2.1 Influence of substrate concentration

Figure 5 indicates the influence of substrate concentration on the elastic modulus (G') of 3 mol% cross-linker concentration. It is clear form the figure, the elasticity of the gels increases with the substrate increases. This can be attributed to increase the probability of the cross-linking reaction at higher substrate

140

120

Fig. 4. Influence of different salt solutions on the swelling of 15/3 St-AAm-MBAAm gels.

;a 2.0

1.0 1.1 1.2 1.3 1.4 1.5 1.6

Log c substrate

Fig. 5. Storage modulus G' as function of substrate concentration.

concentration. The value of loss modulus G" for the gels, were equal to almost zero. Figure 6 shows a logarithmic relationship between G,, and the substrate concentration. The experimental points are fits to straight line of slope 4 [13, 14, 171. This value differ than that established by DeGennes (181, for swollen network at equili- brium and in good solvent.

3.2.2 Influence of cross-linker concentration

The influence of the MBAAm concentrations on the complex dynamic viscosity are shown in the Figure 7. The value of q * increase with time until reach its higher value at approx. 1200min. This mean that the gelation time is relatively higher than that of synthetic polymer hydrogels [19], as a result of the low reactivety of biopolymer and slow rate of ionic mechanism. The value of q * is increase with increase of the cross-linker concentration, due to increase the cross-linking entanglement point. However, this value is declinal at higher cross-linker

starcwstarke 45 (1993) Nr. 2, S. 55-59 57

Time I rnln Fig. 7. Complex dynamic viscosity (q*) as a function of MBAAm contents.

concentration, as a result of the inhomogeneities of the system and microaggregation of the cross-linker.

3.2.3 Effectiveness of the cross-linker

The effectiveness of the cross-linker were calculated from the value of Gp,, in a comparison with the theoretical values of n, (number of elastically covalent entanglement points) [14]. Table 1 indicates the increase of ne(r) by increasing of the cross-linker concentration, reach to 1.652 for 15/15 gels, and the maximum effectiveness of cross-linker were 2.37%. The value of Me(r), the molecular weight between two entanglement points decreases with increase the cross-linker concentration, as a result of increasing of the number of elastically effective points. The lower section of the table shows the values obtained from various substrate concentrations. The value of n,(r) increases and Me(r) decreases by increasing the substrate concentrations. A maximum effectiveness was 5.78% for 25 wt% total polymer concentration.

3.3 NMR analysis

The 13C-NMR spectrum of 20/20 gels in Figure 8 shows that the signals of AGU (anhydroglucose unit) were as follows: C 1 at 104.8; C 2 at 70; C 3 at 79; C 4 at 82.3; C 5 at 69.8, and C 6 at 63.35 ppm. Small shifts occure in the position of signals com- pared with those in literature, due to alkaline medium; cross- linking, and the reference standared used [20]. New signals appears adjacent to C 6 of AGU (at 60.6ppm), which may be produced as a result of the reaction of starch with acrylamide at this position. Also in the figure, we can see the signals of

Table 1. Comparison Between ne(r) and ne(t) of St-AAm-MBAAm Gels. 15 wt% substrate with various cross-linker concentrations (mol%).

~ ~~

3 378 0.145 13.86 0.0104 1034.5 5 965 0.371 23.102 0.0160 404.31 10 2500 0.961 46.32 0.0208 156.10 15 4300 1.652 69.57 0.0237 090.80

3 mol% cross-linker with different substrate concentration

Wt% Gpi ne(r) ne(t) ne(rYne(t) Me(r)

12.5 177 0.0680 11.55 0.0059 1838.23 15.0 378 0.1452 13.86 0.0105 1034.50 17.5 820 0.3151 16.17 0.0195 555.34 20.0 1800 0.6917 18.50 0.0370 289.14 25.0 3467 1.3320 23.10 0.0578 187.70

k

I . . . . , . . . . I A,.. I . . . . I . . . . I . . . . 4 . . . . I . - . . . . . . . . . . . I . . . I . . . I . . . 190 170 150 130 110 90 70 50 30 Fig. 8. 13C NMR spectrum for 20/20 St-AAm-MF3AAm gels.

PPM

unreacted cross-linker or acrylamide, in the region from 35-48ppm, and of the reacted one on the region from 128.6-136.4 pprn [21]. The signals of -NH-CH2-NH-group of the cross-linker appears at 51.4 ppm. At the higher ppm values, we can see the signals of carbonyl group (hydrolysed amide group) at 180 ppm and the unhydrolysed carbonyl groups at 177- 171.2 ppm. The hydrolysed amide group increase the ionic character of the gels and their elasticity and swelling properties [22]. Also the spectrum reveals, the presence of unreacted cross-linker, which give a reason of the low effective- ness of the cross-linker.

4 Conclusions

Ionic, semi-synthetic gels can be produced via cross-linking of modified starch acrylamide with MBAAm by ionic mechanism. The gels produced have water absorption capacity of 140 g/g. The influence of different salt solutions leads to contract of the gels, however no collaps of the gels takes place, especially in case of trivalent cations. In contrast to the synthetic acrylamide MBAAm gels which suffer from a complete collapsing in 11 A1 (NO& solutions. Rheological measurements reveal that the effectiveness of MBAAm cross-linker is very low reach to its maximum value of 5.78% for 25/3 gels (Me = 187.7). This can be attributed to inhomogenities, free chain ends, loopsand entan- glements within the gels structure. NMR study of the gels

58 starchhtarke 45 (1993) Nr. 2, S . 55-59

reveals that the reaction of starch with acrylamide mainly occurs a t C-6 of AGU. Also it shows the presence of unreacted MBAAm signals, which interpretes its low effectiveness.

Acknowledgement

I would like to express my appreciation to Prof. Dr. W.-M. Kulicke, TMC. Hamburg University. D-2000 Hamburg 13. Bundesstr. 45, Ger- many. for his interst in this work and carrying out the rheological measurements.

Bibliography

[ I ] Wing R. E., W. E. Rayford. W. M. Doane, and C. R. Russell: J. Appl.

[2] Benner, C., and L. Kuniak: Cell. Chem. Tech. 7 (1973), 593. [3] Radlev, J . A. . “Starch and its Derivatives”, 4 th ed., Chapman and

[4] Weaver. M. 0.. R. R. Montgomery, L. D. Miller. V. E. Sohns, C. F.

[5] Fanra. G. F., R. C. Burr, W. M. Doane, and C. R. Russell: J. Appl.

[6] Bracku1a.v. C. E.. and K. B. Moser: J. Polym. Sci. Part A1 (1963).

171 Reyes, Z., M . C. Syz, M . L. Huggins and G. R. Russell: J. Polym. Sci.

181 Jones. D. A. . and W . A . Jordan: J. Appl. Polym. Sci. 15 (1971),

[9] Varnia, I . K. , 0. f. Singh and N . K. Sandle: Angew. Makr. Chemie

Polym. Sci 22 (1978). 1405.

Hall. London. 1968, Chap. 2.

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polym. Sci. 15 (1971), 2651.

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[lo] Bavazeed, A. , S . Farag. and A . Hebeish: StarchiStarke 38 (1986).

[ I I] Khalil. M . l., A . Bayazeed, S. Farag. and A . Hebeish: StarchiStarke

[12] Bohlzn, L.: Colloid. Interface Sci. 74 (1980), 423. [13] Kulicke, W.-M., Y. A . Aggour, H . Nottelmann, and M . Z . Elsabee:

[14] Kulicke, W.-M., Y . A . Aggour, and M. Z. Elsahee: StarchiStarke 42

[15] Oppermenn. W., S. Rose, and G. Rehage: Brit. Polyni. J. 17 (1985)

[I61 Kulicke, W.-M. , and H. Nonelmann: Polyni. Mater. Sci Eng. 57

[I71 Oppermenn, W.: Ang. Makr. Chem. 123 (1984). 229. [I81 DeGennes, P. G.: ”Scaling concepts in polymer physics“ p. Cornell

University Press. Ithaca. New York. 1979, p. 128-162. [I91 Kulicke. W.-M., H . Nottelmann, Y. A . Aggour, and M. Z. Elsabce:

Polym. Mat. Sci. Eng. 61 (1989). 393-397. [20] Kalinowski, H . O., S. Berger, and S. Bruun. in “I3C-NMR Spektro-

skopie.” Georg Thieme Verlag, Stuttgart, New York, (1984). 1211 Leung, W . M. . D. E. Axelson. and D. Syme: Colloids Polym. Sci. 263

[22] Halverson, F., J . E . , Lancoster, and M . N . O’Cannor: Macromol. 18

Address of author: Dr. Y. A . Aggour. Permanent address: Chemistry Department. Faculty of Science, Mansoura University. Demiatta.

Present address: Tokyo Institute of Technology, Research Laboratory of Resources Utilization, 4259 Nagatsuta, Midori-ku. Yokohama 227, Japan. (Received: August IS. 1992).

268-272.

39 (1987), 311-318.

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(1990). 134-141.

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(1985). 1139-1144.

Egypt.

I3C CP/MAS NMR Spectroscopy of Native and Acid Modified Starches

Vasudeva Singh, S. Zakiuddin Ali, and S. Divakar, Mysore (India)

CPlMAS NMR spectroscopic studies of some starches from cereals (wheat. maize and finger millet). pulses (green gram. chick pea). tuber (potato) and root (tapioca). and their respective acid (HCI, HN03) modified starches were carried out. While cereal starches exhibited a triplet signal for their anomeric carbons, pulse. tuber and root starches showed doublets. Line width changes in signals indic- ated that debranching in the above modified starches led to narrow- ing of Ch signals (more pronounced in the case of potato and tapioca starches) and were consistent with the release of branching strains. Potato starch. both native and modified, was found to be different from other starches as inferred from the chemical shift values for their anomeric carbons and line shape. The dihedral angle (4;) calcu- lated from chemical shift values for C, and conformation of dihedral angel (x) as predicted from chemical shift of Ch are discussed with respect to structural organization.

13C CPlMAS NMR-Spektroskopie nativer und sauremodifizierter St5rken. Es wurden “C CP/MAS NMR-spektroskopischc Untersu- chungen einiger Getreidestarken (Weizen. Mais und Fingcrhirse), Starken von Hiilscnfriichten (Grungram, Kichererbse), Knollen (Kar- toffel) und Wurzeln (Tapioka) und deren entsprechenden sauremodi- fizierten (HCI, HN03) Starken durchgefiihrt. Wahrend Cercalienstar- ken Dreifachsignale fur ihre anomeren Kohlenstoffatome aufzeigten, wiesen die Starken die Hiilsenfruchte, Knollen und Wurzeln Dublet- ten auf. Veranderungcn der Linienbreite der Signale zeigten, daB die Entzweigung in den erwahnten modifizierten Starken zu einer Anna- herung von C6-Signalen (starker ausgepragt bei den Kartoffel- und Tapiokastarken) fiihrte und mit der Freigabe von verzweigten Berei- chen ubereinstimmte. Sowohl native als auch modifizierte Kartoffel- starke unterschied sich von anderen Starken. wie aus den chemischen Schichtwerten fur ihre anomeren Kohlenstoffatome und aus der Li- nienform erkennbar ist. Der Dihedral-Winkel (+$). berechnet aus den chemischen Schichtwerten fur C, und die Konformation des Dihe- dral-Winkels (x). wie aus der chemischen Schicht von C,, vorausgesagt. werden hinsichtlich der strukturellen Organisation diskutiert.

1 Introduction Angle Spinning Nuclear Magnetic Resonance ( 13C CP/MAS N M R ) spectroscopy has also been applied to s tudy crystallinity

X-ray diffraction technique has been used a s a n important tool to in cellulose and starch [l]. On the basis of X-rax diffraction probe the crystalline organisation of carbohydrates including studies two pat terns (“A” and “B” types of starches) a re starch. In the recent past. however. Cross PolarisationMagic commonly recognised although a third type (“C”) which exhi-

\tarch/starke 45 ( 1993) Nr. 2, S . 59-62 0 VCH Verlagsgetellschaft mbH, D-6940 Weinhelm. 1993 003X-9056i9310202-0059$0~.50+.25/0 59