Starch samples were prepared from the three kinds of plants growing wild in a seaside district of Japan: that is, from the root of Hama-udo, Angelica japonica A. Gray (Umbelliferae); rhizomes of Hama-gaya, Diplachne fusca Beauv. (Gramineae); and Kobo-mugi, Carex kobomugi Ohwi (Cyperaceae), in the yields of 9%, 12% and 6% of the fresh tissues, respectively. These starches were examined on granular size and shape, content of phosphorus and protein, X-ray diffraction pattern, iodine coloration, swelling power, solubility, amylogram, digestibility of raw starches by glucoamylase, etc, and the characteristic features of them were described. By 6%-amylography, Hama-udo starch was gelatinized at 53°C which is lower in comparison to other starches examined, and showed very characteristic curve with broad peak. The gelatinized Hama-udo starch had a high spinnability. The property of Hama-gaya starch resembled to that of sweet potato starch used as a control. Starch granules from Kobo-mugi were small in size and hardly swelled in hot water.

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Starch samples were prepared from the four kinds of wild beans growing in Japan: Hamanata-mame, Canavalia lineata DC. (Leguminosae); Hama-endo, Lathyrus nmritirus Bigel. (Leguminosae); Yahazu-endo, Vicia angustifolia Linn, var. segetalis Koch (Leguminosae); and Fuji, Wisteria floribunda DC. (Leguminosae), in the yields of 21%, 20%, 30% and 12% of the dry beans, respectively. These starches were examined on granular size and shape, content of phosphorus and protein, X-ray diffraction pattern, iodine coloration, swelling power, solubility, amylogram, digestibility of raw starches by glucoamylase, etc, and the characteristic features of them were described. Some of the properties observed, such as granular shapes, high values of both amylose content and initiation temperature for gelatinization by amylography, were common to those of beans starches. On the other hand, the following characteristics on each starch were found: Hama-nata-mame starch granules were large in size and considered to be homogeneous in gelatinization properties by amylography. The properties of Hama-endo and Yahazu-endo starches resembled to that of Mung bean starch described in literatures, dut Yahazu-endo starch did not show any viscosity on 6%-amylogram. Fuji starch was very small in size and characterized by some features, especially iodine coloration, solubility, and X-ray diffraction pattern, different from these features of other bean starches.

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Measurements have been made of the dielectric constant and dielectric loss of native and gelatinized rice starch at 9.4 GHz as a function of water content. As starch was in a powdered state with a low water content, the dielectric constant and loss were influenced by the degree of packing of the starch in the sample cell, measured as bulk density. Therefore, the dielectric constant and loss were obtained by making corrections to avoid an air volume in the sample cell. There was no difference between native and gelatinized rice starch in the dielectric constant throughout the complete range of the water content. The dielectric loss of native starch was lower than that of gelatinized starch in the range of water content higher than 0.25 g/g (dry starch). The value of tan o of native starch increased as the water content increased up to 0.40 g/g(dry starch), whereas, almost constant values were obtained for a water content higher than 0.40 g/g (dry starch), in agreement with that of free water, i. e., 0.46. In the case of gelatinized starch, however, tan σ increased to a maximum value of 0. 75, higher the value of free water, around a water content of 0.60 g/g(dry starch) decreasing gradually to the value of free water as the water content increased.

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Some physico-chemical properties of starches of cassava, arrowroot and sago were compared with those of potato starch. The influence of washing water on physico-chemical properties of cassava starch was also examined. The amylose content of cassava starch was 17 .9-18.9%, of arrowroot starch 19.4% and of sago starch 21.7%. Cassava starch samples prepared using tap water or 0.5 M CaCl₂ solution contained higher amount of Ca, arrowroot starch contained higher amount of K and sago starch contained higher amount of Na than other starches . However, when demineralized water was used for the preparation of cassava starch, Ca content was low, and thus it was found that the amount of cation in the washing water influenced the cation content of the prepared starch samples. The distribution of particle size showed that the peak was located at around 10.1-20.2 pm for cassava starch, 16.0-25.4 pm for sago starch, 20.2-32.0μm for arrowroot and 32.0-64.0 μm for potato starch. The X-ray diffraction pattern of cassava starch was regarded as C type close to A type, arrowroot and sago starches as C type close to B type. The swelling power of cassava starches prepared using various washing water was largerin the following order: demineralized water tap water>0.5 M CaCl₂. Ca was found to have suppressive effect on the swelling power of starch. Both the viscosity-rising and gelatinization temperature as determined by the Amylograph and photopastegraph, respectively, of the tropical starch samples were slightly higher than those of potato starch. Cassava starch showed the least tendency of retrogradation.

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