Round slices of cucumber flesh of about 10 g each were soaked in eleven kinds of aqueous solution containing 10% NaCl and 20% of various classes of sugar alcohol at 4°C for 44 hours. The soaking solutions were composed of 10% NaCl and 20% sorbitol, maltitol, or commercial products named oligo-sugar alcohols A, T and P. The latter three are mixtures of sugar alcohols with different molecular weights.
The composition of each commercial product was analyzed by the HPLC method, and it was determined that oligo-sugar alcohol A contained 49% sorbitol and 35% maltitol, oligo-sugar alcohol T contained 40% maltitol and 38% maltotriitol, and oligo-sugar alcohol P was rich in oligo-sugar alcohol having a higher molecular weight than maltotriitol, amounting to 74%.
The rate of permeation of NaCl into the cucumber flesh during soaking was hardly affected by the presence of any class of sugar alcohol, because it principally depended on the osmotic pressure of NaCl.
The concentration of sugar alcohol that permeated into the cucumber flesh was generally higher in the presence of NaC1 than that in its absence from the soaking solution. Increasing absolute molecular weight and increasing average molecular weight of the sugar alcohol tended to decrease the permeated concentration. This was because permeation depended on the osmotic pressure created by the sugar alcohol used.
The progress of permeation of NaCl and the sugar alcohols decreased the moisture content of the cucumber flesh. The higher the absolute molecular weight or average molecular weight of the sugar alcohol, the less was the rate of dewatering of the flesh. This is attributable to the lower total osmotic pressure conferred by such classes of sugar alcohol.
These results indicate that the quality of the cured product can be controlled by mixing different classes of sugar alcohol to prepare the soaking solution.

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Soba (buckwheat) noodles were made from soba (Fagopyrum esculentum) flour with konnyaku (Amorphophallus konjac) powder added as a binder. Three kinds of konnyaku powder were used: A, first-grade untreated powder; B, powder A treated with ethanol for 15 min; and C, powder A treated with ethanol and ultrasonic irradiation for 15 min. A konnyaku sol was prepared from each of these types of konnyaku powder to add to soba flour for making soba noodles.
The effect of each type on the quality and preservation of the noodles was studied. The best product was obtained by using soba flour containing 2% konnyaku powder. Changes in the rupture stress and rupture strain of the dough with time were very small, so that the dough did not require rising. The best results were obtained with soba dough containing konnyaku powder C which exhibited the best rupture characteristics and physical properties, the noodles being resilient to break age and the elastic properties being maintained after rising for 1 hr. Moreover, the soba noodles made with powder C were preferred more than those made with 100% soba flour and those containing powder A or B as determined by a sensory evaluation. Soba noodles incorporating konnyaku powder contain a large amount of dietary fiber, and we therefore expect the functional characteristics of the soba noodles to be enhanced. It is concluded that konnyaku powder treated ethanol and ultrasonic irradiation was best suited for use as binder in soba noodles.
After keeping the raw soba noodles in a refrigerator at 5°C for 3 days, the bacterial count increased from 10⁶ to 10⁷/g, while that of the boiled soba noodles decreased to a level of 10³/g.

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In order to investigate the effect of storage method on the freshness of parsley, the parsley leaves were stored in a thermo-hygrostat for 7 days at 4°C and 83% relative humidity(RH) or at 20°C and 91% RH by four different storage methods: leaves only wrapped, leaves wrapped with stems in water, leaves and stems completely wrapped, and no wrapping applied. The weight loss and the contents of chlorophyll and vitamin C in the parsley leaves were determined during storage. Changes in the cell structure were also examined by an optical microscope and transmission electron microscope.
Of the four different storage methods, the leaves wrapped with the stems in water at 4°C and 83%RH resulted in the lowest losses of weight, chlorophyll and vitamin C. This storage method also delayed degradation of the fine structure of the chloroplasts. Storage at 4°C with wrapping was more effective for retaining the freshness of the parsley. The fine structure of the chloroplasts could be used as an indication of the freshness of parsley.

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The retrogradation of sago starch gel with a high starch concentration was investigated by studying the freeze-thaw stability of the gel. The starch samples tested were sago, corn, potato, tapioca and hydroxy propylated wheat (HPW) starch. Each starch sample was prepared for gelling by heating while stirring or with steam, and the gel was examined for its texture, syneresis and Hunter whiteness. The effect of HPW starch on each starch gel was also examined. A sensory evaluation was conducted on Warabi-mochi, which is a high-starch food, that had been cooked with the 5 kinds of starch and was evaluated by the semantic differential (SD) method. “Sago-mochi” and “potato-mochi ”, which were most preferred among the 5 samples, were chosen for another sensory evaluation to evaluate the influence of the gel preparation method. The firmness of each cooked gel with a high starch concentration was similar among the samples. The gel prepared by heating while did not increase its firmness and syneresis with freeze-thaw cycles as much as the gel prepared by steam did. The addition of 20% HPW starch prevented this increase in firmness and syneresis with freeze-thaw cycles, the inhibitory effect being most marked with the sago starch gel. “Sago-mochi” prepared by heating while stirring was more preferred to that by heating with steam.

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Food manufactures are looking to extend the variety of low-fat spreads containing less than 40%fats. Manufacturing low-fat spreads requires a relatively large amount of added emulsifiers and stabilizers to provide the water-in-oil (W/O) emulsion. However, the flavor release and mouth feeling of these low-fat spreads are inadequate because of the stable emulsion state. This study was conducted to establish a method for evaluating the degree of demulsification in the mouth and for providing the technique to produce a stable low-fat spread that can be rapidly demulsified in the mouth. The possible combination of such emulsifiers as monoglyceride (MG), polyglycerol polyricinoleate (PGPR) and organic acid monoglyceride was investigated to evaluate the effect of these emulsifiers on the demulsification of a low-fat spread in the mouth. We measured the electrical conductivity attributable to the salt released from the aqueous phase of various low-fat spread in the mouth. We measured the electrical conductivity attributable to the salt released from the aqueous phase of various low-fat spread which had been stored at 5°C and were then heated to 36°C. It was confirmed that electrical conductivity measurement was useful for evaluating the demulsification of spreads, and that the degree of demulsification could be estimated from the equilibrium value of the electrical conductivitv. The demulsification at 36°C of low-fat spreads containing 20% fat may have resulted from an increase in the hydrophile-lipophile balance (3-6) due to adding organic acid monoglyceride to MG and PGPR. The interaction between PGPR and organic acid monoglyceride seems to have induced demulsification from the experimental results for different concentrations of the emulsifiers. These results suggest that the combination of such emulsifiers as MG, PGPR and organic acid monoglycride would enable 20% low-fat spreads to be manufactured which are stable during the preparation and can be demulsified in the mouth with good flavor-release characteristics.

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The effect of water activity (Aw) on the antioxidative ability of various high-molecular-weight polysaccharides, proteins, spices, table luxuries and food industry by-products was examined in a powder model system. Each of these samples was mixed with linoleic acid in the ratio of 4: 1 (w/w)and incubated at various levels of Aw and 50°C.
No antioxidative ability of the potato starch, cellulose, curdlan and konjalc powder polysaccharides was apparent at Aw 0.2-1.0.
The antioxidative ability of the soy protein isolate (SPI), and zein and casein proteins was correlated with Aw. Their peroxide values (PV) remained low during storage at Aw 1.0, and in the case of zein, at not less than Aw 0.8.
In the case of garlic, turmeric, ginger, green tea, coffee and cocoa, their antioxidative abilities were apparent during storage in the Aw range of 0.2-1.0.
Except at a low Aw level, the antioxidative ability of sake lees and wheat bran was apparent during storage, while that of rice bran was shown regardless of Aw.

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Zein and a soy protein isolate (SPI), the peptide derived from SPI (SPI-P), and an amino acid mixture corresponding to these proteins (zein-AA and SPI-AA) were examined for their antioxidative ability in a powder model system and sorption isotherms.
The relationship between their antioxidative ability and the state of water molecules was investigated.
The antioxidative ability of zein was apparent at high water activity (Aw), while that of zein-AA was shown in the range from low to moderate Aw.
The major amino acids of zein, e. g. proline, glutamine, leucine and alanine, were individually examined for their antioxidative ability. Only proline showed this ability. In the absence of an amino acid from the amino acid mixture corresponding to zein, the sample without proline showed no antioxidative ability.
The antioxidative ability of SPI was demonstrated in the range of high Aw. On the other hand, the ability of SPI-AA was shown in the range from low to moderate Aw, while an intermediate pattern between these was obtained for SPI-P.
The sorption isotherms for these samples rose in the high range of Aw. Under the same conditions, the proteins and the peptide showed antioxidative ability, but the amino acid mixture did not.

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This study was carried out to clarify the antibacterial effects of spices and their ethanol extracts(1g/10m/).
Salmonella enteritidis and Escherichia coli strains did not grow after exposure for 120 seconds in water containing the ethanol of clove at more than 8%, and S. entertidis and methicilin-resistant Staphylococcus aureus (MRSA) strains did not grow under the same conditions in water containing the extract of oregano. On the other hand, the aqueous solution containing the 8% extract of rosemary inactivated MRSA with 10 seconds of exposure. The ethanol extract of rosemary among the eight spices tested in this study showed the strongest antibacterial activity against the food-poisoning bacteria.
Bacillus cereus did not grow when exposed for 120 seconds in water containing the extract of rosemary at more than 80%.
The sensory evaluation by young women panelists showed a preference for chicken seasoned with allspice to over all the other tested powdered spices, this being followed by nutmeg and marjoram preference. Chicken seasoned with ethanol extracts of oregano and sage were preferred over the other extracts. These results were statistically analyzed by the Spearman or Kendall method.

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A comparative sensory evaluation, microscopic observation, measurement of particle distribution, and measurement of physical properties was conducted on Kinton prepared either by being mashed in a food processor or by being strained.
Sensory tests showed that Kinton mashed by a food processor for 50 sec. was the most preferred. It was more glossy, sticky, smooth and tasty than the strained type.
The longer Kinton was mashed, the more was the cell separation, cell rupture and amount of starch exuded from the rupture cells. In addition, the clustere of intact cells became smaller. Compared with the traditional method of straining strained, same result could be obtained. The different structure might have affected the glossiness, stickness and smoothness.
The longer it was mashed, the greater the apparent viscosity became, and the lower the breaking stress and loss tangent became.
The hardness of strained Kinton was greater than that when mashed, although this was not significant by the sensory test.

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Three kinds of sesame seed samples (washed and dried seeds, roasted seeds and dehulled seeds)were pulverized by a cooking mixer. The free oxalic acid in each sample was extracted into boiling water, and the total oxalic acid was extracted into 0.5 M hydrochloric acid. The concentration of oxalic acid in the extract was determined by ion chromatography. The amounts of total and free oxalic acid in 100 g of dried sesame seeds were found to be 1,750 mg and 350 mg, respectively, and 100mg and 50 mg, respectively, in 100g of dehulled sesame seeds. The difference between the total and free oxalic acid gave the content of calcium oxalate in the sesame seeds. The calcium oxalate contents per 100 g of dried and dehulled sesame seeds were respectively 2,323 mg and 83 mg as the monohydrate, this corresponding to 636 mg and 23mg of calcium. Almost all of the calcium oxalate was contained in the hulls of the dried sesame seeds. The total calcium per 100g of dried sesame seeds was determined as 1,210 mg, with 636 mg of calcium fixed as the oxalate. The remaining 574 mg of calcium are considered to be available for easy digestion. The calcium oxalate crystals in the hulls of the sesame seeds were aggregated particles composed of longish hexagonal plate crystals and were estimated as the monohydrate.

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It is important to know the behavior of lipid peroxidation products in foods because lipid hydroperoxides are known to decrease food quality and safety. We have reported that the stability of linoleic acid hydroperoxide (hydroperoxyoctadecadienoic acid; HPOD) in the water system. Although the hydroperoxides have been believed to be so unstable at high temperature that they decomposed immediately, the stability of HPOD at high temperature has not been exactly provided. In this study, we examined HPOD decomposition in the oil system kinetically. In tri-n-caprine as the model of oil system, HPOD was lost completely within 1 h at 170°C, while only 20% was lost for 2 h at 100°C. Moreover,40% remained after 72 h at 50°C. Then, HPOD was stabler in oil than in water. According to activation energy, however, it was estimated that HPOD decomposition mechanism in oil was similar to that in water. Thus the homolytic cleavage of the hydroperoxy group to alkoxy and hydroxyl radicals was responsible for the decomposition of HPOD in both systems. Besides, butylated hydroxytoluene is such a strong radical scavenger that it could suppress the decomposition of HPOD.

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Gomadango was made by adding 10,20 or 30% of wheat starch or wheat flour to glutinous rice flour. The effect of those additions on the formability and taste of gomadango were examined.
The breaking stress of the dough was initially decreased by the addition of wheat starch and wheat flour, but after steaming, increased to a higher value than the control with no addition.
The percentage weight loss of gomadango was increased with increasing amo unt of added wheat starch and wheat flour. This weight loss was larger with wheat flour than that with wheat starch.
The formability of gomadango was enhanced by the addition of wheat starch and wheat flour to result in a better appearance than that with no addition. The color of gomadango added with wheat flour was deeper, this depth of coloratin increasing with the amount of wheat flour added.
A sensory test showed that gomadango samples with 10% wheat starch and 10% w heat flour were preferred to the control sample without either of these additives in the total evaluation, while the sample with 10% wheat flour had the most favourable color and flavor.

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