Fructose-transferring enzyme (EC 3.2.1.26) was isolated from the culture filtrate of Penicillium oxalicum by acetone precipitation, Butyl-Toyopearl and DEAE-Toyopearl column chromatographies. The homogeneity was demonstrated by polyacrylamide gel electrophoresis. Optimum pH of the enzyme was 5.0 and optimum temperature was 50-55°C. The enzyme was stable below 55°C for 30min at pH 5.0 and below pH 8.5 for 30min at 30°C. The enzyme synthesized mainly neokestose and 1-kestose from sucrose. The ratio of synthesized neokestose to 1-kestose increased with lowering pH, and with increasing the concentration of sucrose.

View full abstract

Population of the cigarette beetle was monitored by traps baited with a synthetic sex pheromone (serricornin, 4, 6-dimethyl-7-hydroxynonan-3-one) and food attractant (extract of herb) in 16 factories of hand-extended fine noodles. The beetles were found in all factories tested and a few drug-store beetles (Stegobium paniceum L.) were also detected in traps of 9 factories. The cigarette beetles were caught from May to Nov. and at least four peaks of population outbreaks were observed; from May to Jun., late Jun., late Aug. and early Oct.. Although the beetles were trapped at all places in a factory, surroundings of wheat flour, products and trash, corners of rooms and crevices of floors were the most probable sites of adult emergence.

View full abstract

Self-rejection type of dynamic ultrafiltration membranes on ceramic supports were applied to recovery of β-amylase from the waste water of sweet potato starch industries. Four ceramic supports which have different pore sizes; 0.05, 0.4, 1.0, and 1.6μm, were tested to prepare dynamic membranes. The supports of which pore size was under 1.0μm were suitable for this purpose, because high rejection and flux ability was obtained. Changing the flow rate from 0.5m·s_-1 to 2.5m·s_-1 during dynamic membrane formation gave membranes with a higher rejection and flux stability rather than the constant flow rate of 0.5m·s_-1. The total recovery of β-amylase and protein were 79% and 94%, respectively, when the waste water was concentrated to 8 folds.

View full abstract

A statistical method for the yearly trend of seasonality of food consumption was developed here. Seasonal concentration and mean consumption time were employed for two indexes of seasonality. Seasonal concentration and mean consumption time in a year were defined by length and angle of the mean vector, respectively, where the mean vector was taken over 12 monthly consumption vectors in the year. The trend of seasonal concentration was analyzed by the linear regression and then by maximum marginal likelihood method for smoothing serial data. The trend of mean consumption time was analyzed by the linear regression of angular statistics. This method was applied to the data of processed food consumption, which were believed to have little seasonality of consumption. The linear regression of seasonal concentration in years showed that the 27 species among 66 of processed foods were under the trend of year-round consumption and 14 species were under the trend of season consumption. For 24 species, the use of the smoothed curve given by the maximum marginal likelihood method for smoothing serial data was recommended for obtaining the trend of seasonal consumption rather than that of the linear regression line. Mean consumption time were shown to shift significantly for 34 species, just more than half the number of the data sets in this study. For only 9 species, any changes could not be detected in both seasonal concentration and mean consumption time.

View full abstract

A method for determining ruptured and damaged granules in Ann samples was examined on the basis of the solubilized starch content by α-amylase treatment. Samples containing all kinds of Ann granules, namely ruptured, damaged and intact granules, and those containing both damaged and intact granules which were referred to as samples without ruptured granules, were prepared from each Adzuki Ann of commercial Japanesestyle confections and bean-jam buns, and from commercial dried Adzuki Anns. When the solubilized starch contents by the enzyme treatment were A and B% for the sample containing all kinds of granules and for that without ruptured granules, respectively, the proportion of ruptured granules (RG%) in an Ann sample was estimated from the equation, RG=100 (A-B)/(100-B). Nearly all the starches in damaged granules were found to be solubilized by the double treatment with the enzyme. When the solubilized starch content by the double treatment of a sample without ruptured granules was C%, the proportion of damaged granules (DG%) in the Ann sample was estimated from the equation, DG=C(100-A)/(100-B). It was found that the proportions of ruptured and damaged granules in the twenty Ann samples analyzed varied from sample to sample and the average composition of the samples was 61.7% intact, 31.3% damaged and 6.9% ruptured granules.

View full abstract

A simple column chromatographic procedure for analysis of chlorogenic acid analogue (Chl) was developed. Phenolic fraction containing Chl was extracted from plant food with 0.01M acetate buffer (pH 5) and the fraction was applied to a DEAE-Toyopearl_TM column (11×30mm). The column was washed throughly with 0.1M phosphate buffer (pH 7), followed by elution of Chl adsorbed in the Toyopearl_TM gel with 0.1N hydrochloric acid. The content of Chl was obtained from the absorbance at 325nm of the eluent spectrophotometrically, or was estimated from the absorbance at 520nm of a red solution formed by the reaction between Chl adsorbed in the above column and Hoepfner reagent colorimetrically. In several foods, slightly lower analytical value of Chl was found by the latter method than that by the former one in this DEAE-Toyopearl_TM column chromatographic procedure. The recovery rate of Chl by the spectrophotometric method was ranged from 99 to 102%.

View full abstract

A near infrared reflectance spectroscopic (NIRS) method was evaluated for potential usage in determining the amount of 7S and 11S globulins of ground whole soybeans. Near infrared reflectance spectra of the 7S and 11S fractions isolated from defatted soybean flakes were compared to search for characterized wavelenghts for each fraction. Subsequently, near infrared reflectance spectra of ground whole soybeans were measured and compared with those of the isolated 7S and 11S fractions. A multiple linear regression analysis with the data between ultracentrifugal and NIRS analyses on 7S, 11S and the ratio of 11S to 7S (11S/7S) was carried out to make a calibration using 18 calibration set. Correlation coefficients of the regression and standard errors of estimate of respective components from the regression were satisfactory. When performance of the calibration obtained was evaluated by using 8 unknown samples, the standard errorrs of difference between the values by ultracentrifugal analysis and NIRS prediction were 1.39%, 1.32% and 0.10 on 7S, 11S and 11S/7S, respectively. In conclusion, the results suggest that NIRS method has possibility of rapid determination for those components of ground whole soybeans.

View full abstract

We studied on the seasonal changes of asparagine, aspartic acid, glutamine and glutamic acid contents and activities of asparagine and glutamine synthetases and asparaginase and glutaminase in stalks and roots of two varieties of sugarcanes, 'Chikusha' and 'N:CO 310'. The highest activity of asparagine synthetase was observed in the basal part of stalks in August, whereas that of asparaginase was observed in September. Asparagine synthetase showed the highest activity at root in June and/or July. In 'N:CO', asparagine content in the basal part of stalk continued to decrease until October, whereas that in the upper part of stalk increased in September to November. In 'Chikusha', asparagine showed the highest content in the stalk in July, and its content increased in the middle and top parts of the stalk in September to November. The best harvest time of 'Chikusha' sugarcane is considered to be in November on the basis of the highest weight and asparagine contents in stalk.

View full abstract

A dehydrating device comprises high osmotic pressure substance, polymeric water absorber and hydrophilic alcohol, which are co-present and are integrally covered with a semipermeable membrane allowing selective permeation of water. The dehydration device called contact-dehydrating sheet, has an excellent capacity for dehydrating foodstuffs. The behaviors of water removal of beef and tuna meat during the sheet dehydration were studied. Samples of 1.5cm thick were dehydrated by covering the sample slabs with the sheet on the top side. The uppermost part of sample slab was dehydrated faster than the other parts. The mean weight decrease of sample slab during 24-h dehydration was about 10-22%. The dehydration rate was found to be largely dependent on the muscular water-holding capacity. The adipose tissue in bovine muscles was considered to be a hindrance in the diffusion of water molecule from the bottom to the uppermost layer of sample slab and to the sheet. Due to the relative low contents of adipose tissue and connective tissue, the dehydration rate of tuna meat was found to be generally higher than that of bovine meat.

View full abstract

A sheet containing highly osmotic agents was used for foodstuff dehydration. This sheet can remove the water in the foodstuffs when it comes in direct contact with them. Color changes of sheet-dehydrated beef were studied. Beef round cuts of 1.5cm thick were dehydrated by covering the samples with the sheet on the top side. After dehydration for 5, 12 hours as well as 1, 2, 3 and 5 days at 3°C, samples were sliced horizontally along the treated side into 3 layers of equal thickness. The uppermost layer (U) was found to be dehydrated the most, wherein the moisture content decreased from 71.7 to 59.1%. A dark red color has gradually developed in the U when dehydration time was prolonged. There was a parallel increase in both the TBA value and ratio of metmyoglobin in both the control and dehydrated U. A preventive effect on oxidations of lipid and myoglobin could be observed when beef was dehydrated for more than 2 days. However, oxidations of myoglobin and lipid were not the main factors in the formation of the dark color of U, but rather the concentration of red myoglobin pigment, in which the iron level was considered over 4mg of Fe/100g meat was considered to be the main cause of this darkening. There was a gradual change in the color at the surface of control and lower layer forming into a yellowish-brown color of metmyoglobin due to exposure to air. The inner layers were dehydrated less (from 71.7 to 68.0%) which might suggest that owing to indirect exposure to air, maintained a desirable redness.

View full abstract