The effect of the temperature on the properties of the gelatin-agar gel at making the mixture of gelatin and agar was investigated. The yield value of gelatin-agar gel depended only on the temperature at which gelatin was mixed with agar. Thus after mixing the both components at a certain temperature, the yield value was not affected by any heat treatment below 90°C. The component which is influenced by the mixing temperature is not the gelatin but the agar.
The effect of gelatin-agar ratio on the rheological properties of gel was studied in detail. The yield value of the gel increased with the concentration of gelatin or agar. The melting point of the gel, however, decreased with increasing ratio of gelatin to agar. Elasticity and yield value were measured successfully with a curd-tension meter attached with a recorder.
The two 2-TBA methods, Jacobson and Kirkpatrick's with the use of purified n-propanol and YuSinhuber's without the use of an organic solvent, were compared for effects of irradiation doses on the press juices of both control and irradiated samples; the former method did not show an labsorbance near 530mμ but the latter showed maxima at both 430 and 530mμ. The method of Jordan and Veatch for determination of carbonyl compounds was also examined on the press juice but no sharp maximum was observed. Relations between the off odor induced by irradiation as well as the detection of deterioration on storage and absorbances at 430 and 530mμ, by Yu-Sinhuber's method, were also studied but no definite relation between the absorbances and the off odor and deterioration could be found. The 2-TBA method and alcoholic alkaline titration method were also compared for the detection of deterioration during the storage of the control sample; the latter method appeared to be more reliable at the present time.
The samples sealed under vacuum in Irax film were irradiated at dose levels of 2, 3, 4 and 4.6×105r and some of these samples heat-treated immediately after irradiation for removal of the off odors detected previously. The 2-TBA tests indicated that a significant decrease in absorbance at 530mμ was observed by the heat-treatment but no difference at 430mμ. Although a slight difference between the irradiated and irradiated, head-treated samples was detected by a panel test, the latter method, however, prolonged their shelf-life; no sign of deterioration up to 184 days compared with 45 days (in the preceeding report) by irradiation alone. Duplicate runs on bacterial counts during a period of 30days showed that the count of the irradiated sample, 4×105r remained around 10102 all through the testing period. A relation between dose rates and shelf-life was also discussed.
From dietary surveys on malnourished infants aged 12-18 months in various rural regions, the following results were obtained. 1. Daily nutritional intakes were very small: 250-500 Cal. in total, 33-66 Cal. per kg of body weight and 0.9-2.7g of protein per kg of body weight. 2. Their diet was lacking particularly in sulfur-containing amino acids, tryptophan or methionine.