The effects of surfactants and a variety of additives on the fluorescent behavior of four fluorescent whitening agents were investigated at 20°C. The used surfactants were two cationic (HDPC, HDAB), two anionic (SDBS, SDS), and a non-ionic ones (B-35). The main additives were alkylpyridinium salts, alkylammonium salts, and cyanoolefins. The surfactants had a remarkable influence on the fluorescence intensity and the maximum fluorescence wave length. In general, the intensity increased sharply with an increase in concentration above cmc, regardless of the ionic properties of the surfactant micelles. However, in the HDAB solution, the intensity for some anionic fluorescent agents decreased first with an increase in concentration of HDAB, and then increased with an increase in concentration above cmc, and in HDPC solutions the intensity for all fluorescent agents only decreased monotonously. It was found that these rather complicating changes in fluorescence intensity depended on the extent of electrostatic, and hydrophobic interactions of the fluorescent agents with micelles as well as the ionic properties of the surfactants. In addition, disappearance of the fluorescence intensity due to HDPC was discussed in terms of the energy transfer from the fluorescent agents to HDPC in the favorable molecular arrangement. Concerning additives, pyridinium salts always decreased the intensity. This observation also supported the above interpretation.
A TLC-FID method to determine four glyceride types (S3, S2U, SU2, and U3) of fats was developed. Dipalmito-olein, palmito-diolein and triolein were quantitatively oxidised to the corresponding azelaoglycerides with KMnO4, but not tripalmitin. These azelaoglycerides and squalane added as an internal standard were separated on silica-gel TLC and determined with FID. Very good agreement between the determined and calculated compositions was obtained for some synthetic triglyceride mixtures with less polyenoic acid, but not for those with much polyenoic acid. The glyceride type composition of some natural oils and fats with less polyenoic and hydrogenated fats was determined by this method.
A new analytical method by gas chromatography-mass spectrometry is described for detection and determination of [2, 2-2H2] stearic and [2, 2-2H2] oleic acids as stable isotopic tracers. The content of methyl esters of the [2, 2-2H2] fatty acids in a mixture of the corresponding labeled and unlabeled fatty acid methyl esters can be calculated from the proportion of the peak intensities of ions at m/z 76 and 74 due to the McLafferty rearrangement of fatty acid methyl esters. The method was applied to trace the nonenzymic and enzymic interesterification reactions using [2, 2-2H2] fatty acids as tracers.
The following two fry tests were carried out to investigate the synergistic antioxidant effects of tocopherol (Toc) and citric acid (CA), monoacylglyceryl citrate (MGC), L-ascorbic (AA) or erythorbic acid (EA) on fried foods. In Fry Test I, potato chips were fried once at 160°C with lard systems consisting of a mixture of d-Tocs and one of each of the synergists. Five fryings at 30 min intervals were carried out at 170°C for Fry Test II. Stability of the chips toward oxidation was evaluated primarily on the basis of changes in the POV of the chip lipid fraction during a storage at 60°C. 1) All the tested synergists contributed enhanced the antioxidant effects of Toe on potato chips. The time required to attain POV 30 and for a perceivable odor to occur during storage at 60°C of EA CA>AA>MGC. 2) Potato chips stored at 60°C showed a tendency such that the remaining Toc was higher with increased oxidative stability. 3) In Fry Test II, there was little difference in POV, carbonyl value or total Toc content of lard containing CA or EA in the initial and final fryings. Also, the oxidative stability of chips fried in each lard system hardly varied with an increase in fry times, when stored at 60°C. Notably, the synergistic antioxidant effect of EA with Toc on potate chips was still maintained provided the lard system was heated at 170°C for 2h.
In order to find new aroma chemicals, various type of terpenoid compounds are prepared using prenyl chloride (1) as a raw material. The main reaction is the condensation of (1) and aldehydes with aqueous sodium hydroxide (ca. 50%) in the presence of a tetrabutylammonium iodide catalyst. The prenylated aldehydes (2) are converted to the corresponding alcohols (3), acetals (4) or nitriles (5). Alcohols (6) are also obtained from (2) and various allylic Grignard reagents. Those compounds are evaluated by their odor : 2, 5-Dimethyl-2-propyl-4-hexen-1-ol (3c), 2, 5-dimethy;-2-phenyl-4-hexenal (2 e), 2, 5-dimethyl-2- (p-methylphenyl) -4-hexenal (2 h), 2, 5-dimethyl-2-propyl-4-hexenal dimethyl acetal (4 c) each emited an odor that will qualify them for cosmetic application.
As a part of research program for the synthesis of biologically active substances, the present study was undertaken to synthesize (Z) -9-tricosene (11), a sex pheromone of house fly (Musca domestica), and other related compounds, (Z) -13-heptacosene (12), (Z) -13-nonacosene (13) and (Z) -14-nonacosene (14). The starting materials including saturated aliphatic alcohols (1) (3) (C13 : 1-tridecanol, C14 1-tetradecanol, C15 : 1-pentadecanol) were processed with relatively simple procedures such as bromination, Grignard reaction and dehydration and the sex pheromones (11) (14) were obtained from compounds (1) (3), respectively with yields of 3944%. The IR, NMR, and MS spectra of alcoholic compounds (8) (10), precursors of the sex pheromone derivatives were also determined.