The internal standard method for gas chromatography of the aroma of roast and ground coffee is affected by the absorbing ability of ground coffee. The effect of particle size and roasting degree of coffee on this method was studied. (1) The ground coffee consisted of particle sizes between 20-28 mesh showed the maximum amount of aroma components. The peak height of internal standard(I. S.)decreased according to smaller particle size. The peak height of I. S., however, was able to corrected by the surface area calculated from particle size and its distribution because the high correlativity was observed between them(coe fficient of correlation=-0.974).(2)In comparing the results of gas chromatographic analysis of roast coffee in six degrees, the peak height of I. S. decreased as roasting, but the high correlativity(coe fficient of correaltion=0. 965)was observed between the peak height of I. S. and L value. As a result of the correction of the peak height of I. S. by the L value, this internal standard method could apply to the coffee beans having different roasting degrees. (3)It was suggested that the ratio of peak 5, acetaldehyde, to peak 8, isobutyraldehyde, was an useful index of roasting and variation of quality of coffee.

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Papain was immobilized with citrus inner-peel pectin. The pectic substances were prepared by treating citrus inner-peel with an alkaline solution. To this pectin solution, papain was added and the mixture was gelatinized in the presence of Ca²⁺. However, it was found that at the same time, the active site of papain(-SH group)was attacked by the gelating agent(Ca²⁺). Immobilized papain was prepared after the active site of papain was protected with Hg²⁺. This immobilized mercury-papain completely restored its activity by the addition of L-cysteine alone, but the pectin-Ca²⁺ carrier was hardly affected by this treatment. Activity of this immobilized papain was maintained at high levels for over 25 repeated usage.

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In order to examine the changes in the amino acid content of fried Kamaboko(fried fish cake) by gamma-irradiation and by storage, samples of fried Kamaboko and its extractives were analysed using amino acid analyzer. Fried Kamaboko was prepared mainly from frozen ground Alaska pol1ack, packed and sealed under air in a cellophane film bag coated with polyvinylchloride. It was irradiated with a dose of 3 kGy and subsequently stored at 10°C for 56 days and 30°C for 21 days. The results obtained were as follows:(1)Eighteen individual amino acids of fried Kamaboko showed no loss as a result of irradiation. A small quantity of methionine sulfoxide and sulfone was formed by irradiation. (2)The total bacterial count per g of the irradiated sample was<30 before storage, and it was 10⁴-10⁶ after 6-7 days at 30°C and over 10⁷ after 14 days. The reduction of the total amino acid content(TAAC)of the irradiated sample was negligibly small after 14 day and about 4.5% after 21 days. The TAAC of the extractives increased rapidly up to 3.5 times that of 0 day's. (3)During 56 days storage at 10°C, there was no apparent challge in the TAAC of the irradiated sample and also of the extractives. The combined treatment of irradiation and low temperature storage was found to be fairly effective.

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A simple, rapid method has been developed for determining adenosine triphosphate (ATP), adenosine diphosphate, adenosine monophosphate, inosinic acid (IMP), inosine, and hypoxanthine in chicken muscle. The determination was carried out by high performance liquid chromatography using a ultraviolet monitor. In this method, average recovery values added to chicken muscle were in the range of 93.5-100.5%. Samples were obtained from "Yamato" and "Broiler" type chickens that were raised in the experiment station. The results indicated that IMP distributed in breast, thigh, and neck muscles, whereas it was not found in skin and edible viscera. IMP content increased according to the age of the birds. At higher temperature, IMP quickly decreased and K value obtained by quantitative changes of ATP related substances increased contrary to IMP. However, IMP and K value did not change significantly for a month at -15°C. An investigation of the changes of IMP and K value by cooking revealed that IMP cotent markedly decreased by boiling and K value slightly increased by frying.

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K values and the oxidation states(values of AV, POV, COV and TBA V)of total lipids of dorsal ordinary meat of mackerel, Scomber japonicus and frigate mackerel, Auxis tapeinosoma under low temperature preservation(+5°C cold storage, -3°C partial freezing and -20°C freezing) were measured and these samples were submitled to sensory tests. (1) In case of +5°C cold storage, K values, AV, POV, COV and TBA V of both fish stored for 2 days were low and the sensory tests also gave good results, therefore, both fish were found to be edible as slices of raw fish ("Sashimi"). In the cold storage for 4 days, K value, AV, COV and TBA V were a little higher, but POV was low and the results of the sensory tests were a little inferior, so both fish were edible as cooked. In the cold storage for 6 days, K value reached to 60%(the first rotten stage), and AV, COV, TBA V also became remarkable high valuges but POV was not so high, and the results of sensory tests were not good. Comsequently both fish were not suited for eating. (2) In case of -3°CPF storage, K value, AV, POV, COV and TBA V of both fish stored for 10 days were low and the results of sensory tests were also good, there fore, both fish were found to be edible as "Sashimi". In the PF storage for 2p days, K value and AV went up a little high, and POV, COV, TBA V were not high enough. The results of the sensory tests were a little inferior, therefore, both fish were edible as cooked. In the good. Consequently both fish turned out to be inedible. (3) In case of -20°C freezing storage, K value, POV, TBA V of both fish stored for 60 days were not too high, but AV and COV showed high value, and the results of sensory tests were good. Thus both fish were found to be edible as "Sashimi".

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Clycosyl sucrose(GS), or sucrose coupled starch syrup, is a natural sweetener with a low-cario-genicity, obtainable by subjecting a mixture solution of starch and sucrose to the transfer action of cyclodextrin glucanotransferase(EC 2. 4. 1. 19). The application of GS to pectin jelly and its stability were studied. The use of GS in high methoxyl pectin(HMP)jelly of either rapid- or slow-set pectin gave satisfactory gel strength. In a model experiment using 65% GS or sucrose and 0.75-1.0% pectin, the pH required to obtain satisfactory gel strength in the rapid- or slow-set pectin jelly with the use of GS was ca. 3.2-3.5, while it was slightly lower when sucrose was used. In low methoxyl pectin(LMP)jelly, satisfactory gel strength was obtained with 30% of GS, pH 3.8, and Ca²⁺ concentration of 25mg/g pectin. LMP gel formation with GS was much more easier than that attained with sucrose at lower concentrations of Ca²⁺, pectin and sugar, and satisfactory gel strength with GS was obtained at a slightly higher pH. In pectin jelly with satisfactory gel strength, GS was stable; scarcely hydrolyzed by acid at a pH of 3.3 or higher when used in HMP jelly, and at 3.6 or higher in case of LMP jelly.

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Nucleosides and purine and pyrimidine bases were separated using both of anion and cation exchange chromatography. Anion exchange chromatography was carried out using a column of φ9 mm×220mm packed with Hitachi model 2630 anion exchanger(strongly basic type). Nucleosides and purine and pyrimidine bases were eluted at an early stage by 0.1M ammonium acetate-acetic acid(pH 4.6)separating from nucleotides. The nucleosides and the purine and pyrimidine basesobtained by anion exchange chromatography were moreover separated by cation exchange chromatography. The determination was carried out using a column of φ9mm×400mm packed with Hitachi model 2613 cation exchanger(strongly acidic type), by the stepwise eluting method. Urd, Ura, Thy, Ino and Xan could be separated by 0.05M monopotassium phosphate-phosphoric acid (pH 2.4)as the first eluting solution, Hyp and Guo by 0.4M monopotassium phosphate-phosphoric acid(pH 3.4)as the second eluting solution, and Ado, Cyd, Gua, Ade, and Cyo by 0.4M monopotassium phosphate-potassium hydroxide (pH 5.0) as the third eluting solution. The Nucleosides and the purine and pyrimidine bases in dried purple lavers were determined by the method. The very small amounts of Ade, Gua, Ado, Cyd, and Urd were observed in these samples.

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The rec-assay using spores of Bacillus subtilis strains, H17 Rec⁺ and M45 Rec^-, was carried out on foodadditives from natural origin. For metabolic activation, 9000g supernatant solution of the liver homogenateof Sprague-Da wley male rat previously treated withphenobarbital and 5, 6-benzoflavone was used. Asa results, nine tested samples were all negative inthe spore rec-assays with and without metabolicactivation. Among nine samples, hop oil and garlicoil showed slightly inhibitory effects against Bacillus subtilis.

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The susceptibity of fresh cassava roots to deterioration under tropical conditions has seriously limited its full utilization. The roots are extremely perishable so that a few days after harvest, deterioration may set in, and are consequently rendered unfit for edible purpose¹⁾.Several methods have been devised to preserve the roots, but processing into dried cassava chips, or cassava flour is one of the cheapest and most utilized methods of preservation²⁾. Further, it has been noted that cassava flour can be utilized as a good replacement-source for noodle³⁾, bread, cake and some fermented foods⁴⁾ such as "puto". Thus, it has become important to elucidate the factors related to the production of good quality cassava flour. On the other hand, it has been clarified that the bluish fluorescent components, that is, the coumarin derivatives such as scopoletin, esculin and scopolin are formed in cassava tissue, inresponse to artificial or natural injury, or in relation to physiological and microbial deteriorations occurring during storage.^5)-8) We assumed that such stress metabolites as the coumarin derivatives might be fbrmed in larger amounts in the cut-injured tissue in the course of drying of thet issue since not only cut-injury but also drying must supply a stress to the living tissue cells, and lesser amounts might be produced when the tissue cells die in a shorter period as in fast drying resulting in cassava flour of better quality. Further, we thought that the TLC assay of the above fluorescent components in cassava flour might be useful to evaluate the food quality of the flour. This paper deals with the relation of various methods of making cassava flour with the intensity of the fluorescent components in the flours.

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Sugar components of "Ichida Kaki"(Japanese persimon)before and after the process of drying were investigated by both gas chromatography and thin-layer chromatography, and the following results were obtained:(1)The sugar contents of persimmon determined by gas chromatography were identical with those by Bertrand method.(2)Free sugars contained in the raw fruit were mainly fructose (39%), glucose(38%)and sucrose(23%).(3)The amount of monosaccharides was extremely high in the free sugars of the dried fruit flesh, 51% of which was fructose followed by glucose(48%), whereas the amount of sucrose(1%)was very low.(4)The sugar contents of white powder deposited on the fruit surface were analyzed in comparison with those of the dried fruit flesh and it was found that the ratio of fructose to the free sugar(22%)in the former case was lower than that of the latter(51%).

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