'Setting' of minced-hen-meat sol was utilized to tenderize tough hen meat. When minced-henmeat sol was incubated before heating, gel prepared by heating exhibited such resistance to the teeth as that of pork pressed ham.
After minced-breast-meat sol was incubated at 3, 20, 30, 40, or 80°C, minced-breast-meat gel was prepared by heating at 80°C for 30min. The incubation time necessary for exhibition of maximum shear force value, was shortened when the incubation temperature was raised. Maximum shear force value of gel prepared after incubation at 3°C, was stable for a long incubation time and the value was smaller when incubated at 80°C.
After minced-leg-meat sol was incubated at 3, 20, 30, 40, or 80°C, minced-leg-meat gel was prepared by heating at 80°C for 30min. The incubation time necessary for exhibition of maximum shear force value, was shortened and maximum shear force value was decreased as incubation temperature was higher.
In a word, incubation at 3°C was the best. When minced-breast-meat sol with 0.22% Na₄P₂O710H₂O was incubated before heating, shear force value of minced-breast-meat gel prepared by heating once increased.

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Many analytical methods have been proposed for piperine content determination in black pepper. In these phosphoric acid, modified chromotropic acid (ASTA) and UV spectrophotometric method were compared and by the former two methods higher piperine content was observed than by UV method.
From the organoleptic evaluation of the soup containing piperine or pepper extract dissolved in a coconut oil and emulsified in water, pure piperine was found to show stronger pungency than the pepper extract of the same piperine content determined by the above mentioned methods.
And even by the UV method higher absorption than that of the real piperine content was observed owning to the by-constituents. In order to clarify the difference between the absorbances of pepper extract and the pure piperine, pepper extract was fractioned by thin layer chromatography and absorbance of separated piperine was found to be about 90% of the total amount.
1-Piperoyl pyrrolidine (pyrroperine), a new constituent in pepper having the similar UV spectrum and weak pungency compared with piperine, was determined to have the content of 0.2 to 0.3% in pepper.
It is proposed that UV method operated in the dark is better for determining piperine content in pepper, although even in this case about 10% is overestimated owning to the by constituents.

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The structure of the piperine dimer which is easily obtained by irradiating the suspension of extremely minute crystals of piperine (made by pouring its alcohol or acetone solution into a large volume of water) was investigated. From IR, UV, NMR and MS informations, piperine dimer was found to be all asymmetric four membered ring structure combined head to head bf two piperines; that is 1-(3, 4-methylenedioxyphenyl)-2-(3, 4-methylenedioxycinnamyl)-cyclobutane-3-carboxylic acid-4-(β-acrylic acid)-dipiperidide.

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The photochemical isomerization of piperine (2-trans-4-trans) and synthesis of piperine isomers (2-cis-4-trans, 2-trans-cis and 2-cis-4-cis piperine) were investigated. When piperine was irradiated in an alcoholic solution under a high pressure mercury lamp, there occurred cis-trans isomerization and this photoisomerized piperine was found to be a mixture of isopiperine (2-cis-4-trans) and iso-chavicine (2-trans-4-cis) from the data of UV, IR, NMR and chemical synthesis, and the former to be the major product. This was also certified by piperine homolog, cinnamacrylic acid piperidide which was photoisomerized in the same manner. 2-cis-4-trans piperine was easily synthesized by the method of E. Ott and F. Eichler, but 2-trans-4-cis and 2-cis-4-cis piperine were synthesized as follows. Dehydrobromination of brominated piperic acid gave trans-2-en-4-yn carboxylic acid in good yield, which was converted to its piperidide, following partial hydrogenation gave 2-trans-4-cis piperine, while partial hydrogenation after trans-2-en-4-yn carboxylic acid piperidide had been transformed to its cis form by irradiation under a high pressure mercury lamp, gave 2-cis-4-cis piperine.
The piperine isomers were less pungent than piperine and could not be detected in black pepper.

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Reducing sugar content of irradiated and non-irradiated potatoes during storage at ambient temperature showed no significant differences up to 6 months. After 7 months, reducing sugar content of non-irradiated potatoes decreased with sprouting, but irradiated potatoes showed no significant differences. Reducing sugar contents of the samples stored at 5°C were 2 to 3 times higher than that of the samples stored at ambient temperature. Reducing sugar content of transfered samples from 5°C to ambient temperature for 2 weeks were almost at same levels with samples stored at ambient temperature.
The pattern of amino acids showed no significant differences between irradiated and noninadiated ones irrespective of storage conditions, but pattern similarity decreased with the extention of storage period when compared with samples which were immediately irradiated. Results of crisps quality produced from non-irradiated and irradiated potatoes showed that transfered samples from 5°C to ambient temperature for 2 weeks before processing, were most acceptable of all samples tested. Crisps produced from samples irradiated and stored at ambient temperature was acceptable until 8 months, but after 8 months of harvest due to evaporation of water, shrinkage occurred and cell walls hardened, and these condition resulted in half done products. There was good correlation between crisps colour and reducing sugar contents. From above results, irradiated potatoes were usable for chipping purposes up to 8 months at ambient temperature. The extension of processing period was obtained by irradiated samples stored at 5°C when transfered to ambient temperature for 2 weeks before processing.

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The extraction rate of oil from fish muscle with the solvent immiscible in water was investigated in the early stage of extraction. The experimental results were as follows. The penetration of solvent into fish muscle was caused by two different mechanisms like oil extraction, and the mechanism of dehydration did not change where the mechanism of oil extraction changed. And the most important result was that the ratios of extracted oil and removed water were constant through the early stage of extraction independent of time. With the results described above and our previous results, the following hypothesis of the mechanisms of extraction could be considered. Water and fish oil are extracted with constant ratio through the early stage exchanging with solvent. Oil globules dispersed in the muscle gradually grow large by absorbing the penetrated solvent and then coalesce with each other and make the continuous phase. This is the point of which mechanism changes and then extraction transfers to the late stage in which the mutual diffusion of oil and solvent occurs.

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Volatile components prepared from raw and heated green tea (hiire-cha) by vacum distillation followed by ether extraction were compared by gas liquid chromatography using capillary column.
The aroma components such as 2, 5-dimethylpyrazine, furfural and 1-ethylpyrrole-2-aldehyde which were usually recovered in heat treated food, were slightly produced during heating of green tea.
In case of heating at same temperature, the amounts of dimethylpyrazine and alkyl pyrrol-2-aldehyde in heated high grade tea were slightly lager than that in low grade one.
Two isomeric 2, 4-heptadienals which are considered to contribute to rancid aroma of green tea were remarkably decreased by heating.

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The preventive effect of polyphosphates against maillard reaction by amino acid (glycine) and sugar (D-xylose) was studied.
Only ultra polyphosphate showed effect among tested polyphosphates including trimetaphosphate, hexametaphosphate, tripolyphosphate and pyrophosphate. It possibly depended upon that ultra phosphate has lower pH value and more specific structure than others.

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