This paper describes the effect of sulfur compounds, i.e. diallyldisulfide (DADS), diallylsulfide (DAS) and hydrogen sulfide, on the germicidal activity of ozone to spores of Bacillus coagulans IAM 1115 and Bacillus stearothermophilus IAM 1035. Spore suspensions (10⁷-10⁸/ml) were treated with ozone (0.5mg/l) under a flow rate of 1455ml/min at 20°C. Results were as follows: (1) When B. coagulans spores were exposed to ozone, germicidal effect was significantly enhanced by the presence of DADS or DAS. But, the effect was not demonstrated for B. stearothemophilus spores. (2) DADS or initiated spore germination. It seem that the increase of ozone sterilziation in presence of DADS or DAS depends on spore germination. (3) Germicidal activity of ozone exposure was decreased at the presence of 20mM hydrogen sufide, but increased at the presence of 2mM or 0.2mM hydrogen sulfide. This result is considered to have been caused by the difference of residual ozone concentration and final pH.

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Skim milk, separated from bulk cow's milk gotten from a dairy district in Miyazaki Prefecture, was heated at 85°C for 5min, immediately followed by heating at 135°C in a moment on an experimental scale. The effects of pH, Ca and intact casein micelle on the physical properties (hardness, breaking energy and elastic modulus) of the rennet curd prepared from this high-temperature heated milk were investigated using a rheometer.
The results obtained were summarized as follows:
(1) The physical properties of rennet curd of high-temperature heated and pH-adjusted (6.7-6.0) milk could not be improved up to those of unheated milk. (2) Using Ca-added (80mg/100ml) and pH-adjusted (6.7-6.0) milk, it could be seen that the physical properties of high-temperature heated milk were improved with pH lowering, whereas even the highest values of the physical properties obtained for pH 6.0-adjusted milk rennet curd could not come up to those of unheated one. (3) When unheated casein micelle (360mgN/100ml) of 0.35 or above as unheated casein micelle ratio were added to high-temperature heated milk at 6.6 or 6.2, the physical properties of milk rennet curd were greater than those of unheated one and the rennet curd of pH 6.2-adjusted milk was somewhat better than those of pH 6.6-adjusted one. (4) Rennet curd of high-temperature heated milk at pH 6.6 or 6.2 was remarkably improved by the combination of Ca addition (80mg/100ml) and unheated casein micelle fortification; pH 6.6 or 6.2-adjusted milk rennet curd was attained nearly same as unheated one by fortifing to 0.2 or 0.15 respectively, as unheated casein micelle ratio. (5) From those results it was confimed that an adequate combination of both Ca addition and native casein micelle fortification as well as sutitable acidification was essential for the improvement of high-temperature heated milk rennet curd.

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NAD-dependent alcohol dehydrogenase (NAD-ADH, EC 1. 1. 1. 1) and NADP-dependent alcohol ehydrogenase (NADP-ADH, EC 1.1.1.2) were extracted from strawberry pulp and partially urified with ammonium sulfate fractionation and DEAE-Sephadex A-50 column chromatography. he pH optima of reduction and oxidation with NAD-ADH are 6.0 and 9.0, respectively. On the ther hand, those of NADP-ADH are 8.5 and 9.5, respectively. NAD-ADH is stable in the pH ange between 6.5 and 8.5. NADP-ADH is stable in the pH range between 6.5 and 9.5. Free ulfhydryl groups are essential for the activities of these enzymes as PCMB and o-iodosobenzoic acid ause a drastic inhibition. NAD-ADH reacts only with aliphatic alcohol and aldehyde, while aromatic and terpene alcohols and aldehydes are the better substrates for NADP-ADH than aliphatic nes. These two ADHs in strawberry pulp are supposed to be the same as ADHs found in strawberry seeds from their chemical and physical properties and zymograms on polyacrylamide gel lectrophoresis.

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The changes of lipids in miso were investigated by addition of lipase preparation, Lipase-MY (Meito Sangyo Co. Ltd.). It exhibitted high activity under the condition similar to miso aging, such as pH, temperature and the concentration of NaCl. When Lipase-MY was added in miso, the degradation ratio of lipids and content of glycerol as well as ethyl fatty acids increased, whereas content of ethanol decreased. These results suggested this lipase hydrolysed glycerides to fatty acids and glycerol, and further synthesized ethyl esters from a part of free fatty acids and ethanol produced by yeast. When the lipase-added miso was aged for 25 or 90 days, miso with 0.03 units of lipase/g-miso contained more than twice free fatty acids and their esters of ordinary miso. The aroma was evaluated better than that of ordinary miso by sensory test. However, the aroma of miso with 0.3 units of lipase/g-miso was too strong to be evaluated as suitable for Shinsyu Miso. The changes of lipids in miso (especially the increase in ethyl fatty acids) continued to progress even at lower temperature in the latter stage of aging, whereas the other components were hardly changed at this stage. These facts suggest that the changes of lipids are important factors for harmony of miso flavors.

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Headspace volatiles of five samples during manufacture of the concentrated grape juice (Vitis labrusca L. var. concord) such as raw materials, heating process to extract color, clarification process with enzyme, concentration process and final products have been analyzed by Tenax GC trapping technique and capillary gas chromatography. Nineteen components, including eleven esters, five alcohols, two ketones and dimethyl sulfide, were identified. The loss of headspace volatiles during manufacture was most in heating process to extract color (53.3%), followed by concentrating process (27.3%) and clarifying process (18.1%).

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L-Leucine n-dodecyl ester was covalently attached to gelatin by modification with papain under a specific condition. The product linked 0.44% L-leucine n-dodecyl ester on weight basis and showed a high degree of surfactancy permitting emulsificaton of soybean oil. This surfactant was used as an ingredient for preparing a mayonnaise-simulated emulsion, with the result that the emulsion resembled commercial mayonnaise items with respect to oil-particle size distribution, texturometric parameters on hardness and adhesiveness, viscometric flow behavior, and sensory scores. The use of secondary ingredients including seasonings together with the enzymatically modified gelatin, had no adverse effect on the emulsion formation, Also, the emulsion prepared with this surfactant was characterized by a low degree of drainage formation during storage and found to be stable over a long period of time.

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Natto is a Japanese traditional food made from whole soybeans by the fermentation of Bacillus natto. The change of soybeans saccharides in both quality and quantity was investigated by the gaschromatographic and photometric analysis during manufacturing of natto. Raw soybeans imported from China for natto manufacturing, contained 7.05% sucrose, 1.15% raffinose, 6.34% stachyose, 0.07% myo-inositol and 0.98% starch on dry base. During soaking and steaming, oligosaccharides, myo-inositol and starch were partially lost in soaking water or cooking drain and a part of the oligosaccharides was decomposed. During fermentation, sucrose decreased down to about one seventh, and both raffinose and stachyose decreased to about one third of the starting levels within 10 hours after starting fermentation. Along with the reduction of the sugars, manninotriose, melibiose, glucose and fructose increased up to 2.04% in 12hrs, 1.62% in 8hrs and 0.27% in 8hrs, respectively. Thereafter glucose and fructose decreased rapidly, whereas other oligosaccharides decreased slowly. Levan, viscous polysaccharides produced by Bacillus natto, increased along with the reduction of soybeans oligosaccharides. Neither liberation of galactose nor saccharification of starch were obserbed during fermentation. After maturing, the final products still contained 0.41% stachyose, 1.18% manninotriose, 0.16% melibiose, 0.49% levan and 0.64% starch on dry base.

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Ethanolic extracts of spices and different types of flavouring compounds were tested for inhibition of some species of microorganisms in culture media. Among the tested spices, the extract from cloves was the most inhibitory to all tested microorganisms. Although other spices showed slightly inhibitory effects against gram positive bacteria, they were almost negative against gram negative bacteria. Their effects to the tested bacteria were more active in media at pH 5.0 than at pH 7.0. Phenols, alcohols, aldehydes and organic acid of the flavours used herein inhibited all tested bacteria, except Ps. aeruginosa, at concentrations of 1000 to 5000ppm in media (pH 7.0). These compounds were also inhibitory against fungi below 5000ppm; especially cinnamic aldehyde had much stronger antimould activity than potassium sorbate and inhibited the moulds at less than 10ppm.

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Fish scrap usually comprises about one half of the carcass of raw material fish for processed food. The purpose of a series of studies is to establish recovery methods of proteinaceous materials from the fish scrap by enzymatic digestion and to convert them into useful byproducts such as fish sauces. In this paper, digestion of offal of croaker and horse mackerel by commercial enzymes and composition of scrap of raw materials for Kamaboko and Fish sausage were investigated. Activities and optimum pH of the enzyme examined were as follows. A-P was found to have enzyme activity of 7, 000 F.U. at optimum pH 7, B-SP 20, 000 F.U. (optimum pH 8 and near 11), C-AF 30, 000 F.U. (optimum pH 8), D-M 15, 000 F.U. (optimum pH 5), and E-T 6, 000 F.U. (optimum pH 5) respectively. More than 10% of salt cocentration was necessary to exert preservative effects during enzyme digestion of raw scarp of croaker and horse mackerel. When the enzymes were applied to raw and cooked scrap of croaker and horse mackerel, C-AF showed the highest degree of digestion followed by A-P and B-SP in descending order. D-M and E-T showed the lowest degree of digestion. Cooked fish scrap was less digestable than raw scrap by the enzymes.

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