An evaluation was made on antioxidative and synergistic effects of several emulsifiers on cookie by storage test at 40°C for 12 months after baking. Emulsifiers were added to cookie dough at 0.5%, and effects were evaluated by sensory test and measuring peroxide value of lipid fraction of cookie to compare inhibition of increase of peroxide. Lecithin showed a strong antioxidant effect on cookie. Sorbitan monostearate and sucrose fatty acid ester (hydroxyl value : 362) showed a less effect than that of lecithin. In the case of emulsifiers in combination with a mixed tocopherols concentrate, sorbitan monostearate showed a synergistic effect, and propylene glycol monostearate showed an additive effect. Synergistic effect of lecithin, however, could not be observed obviously because of their strong antioxidant effect.

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The antioxidative effect of astaxanthin on salmon egg phospholipid and salmon triacylglycerol, abundantly present in n-3 polyunsaturated fatty acids, was examined by monitoring peroxide value (PV), carbonyl value (CV), and remnant ratios of astaxanthin, tocopherol and docosahexaenoic acid (DHA) in the substrates during autoxidation at 30°C.
The induction periods of phospholipid with 500 ppm tocopherol, with 500 ppm tocopherol and 690 ppm astaxanthin were prolonged respectively 2.4 and 3.6 times longer than that without them. Astaxanthin exhibited more effective antioxidative activity toward polyunsaturated phospholipid than that toward polyunsaturated triacylglycerol.
Autoxidation of polyunsaturated phospholipid could be effectively prevented by addition of astaxanthin and tocopherol.

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A super water-repellent surface with maximum contact angle of 174° was previously obtained by solidifing a wax, alkyl ketene dimer, from a melt. This surface was fractal with dimension of D≈2.3. The surface area magnification factor became quite large due to the fractal structure and then the contact angle of a water droplet also very large. This paper is an extension of the study for clarifying why the alkyl ketene dimer forms a fractal surface. Crystallization of the alkyl ketene dimer from the melt was observed by polarizing optical microscope and DSC measurement. Attempt was also made to develop a super water-repellent paint containing the alkyl ketene dimer. Flake-like crystals of the alkyl ketene dimer were observed on the painted surface following drying of the paint-layer, and super water-repellency of the surface was noted. Through the use of triacylglycerols and dialkyl ketones, the super-water repellent surfaces have been also obtained. It has been experimentally shown that any wax with a contact angle exceeding 90° become super water repellent by making the surface sufficiently rough.

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Poly (oxyethylene) -2-hexyldecyl sulfates, having various oxyethylene units between hydrophilic and hydrophobic moieties in a double-tail anionic surfactant, were synthesized and the effects of the number of oxyethylene units on the properties of micelles and/or middle-phase microemulsion were investigated.
Critical micelle concentration decreased with increase in oxyethylene units, but the equilibrium surface tension was independent of oxyethylene chains. For surfactants possessing oxyethylene units of 1-5, dehydration from oxyethylene chain portions in micelles was observed with increasing their concentrations. With the formation of the middle-phase microemulsion, surfactans having oxyethylene groups may increase both hydrophilic and hydrophobic interactions; increase in the number of oxyethylene chains resulted in the increase of solubilizaion parameter, depression of interfacial tension, and increase of optimal salinity.

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A novel method using isooctane was established for determining the peroxide value (PV), widely used as basis for assessing the rancidity of oil and fat. This was done through the collaboration of 10 research organizations by potentiometry using an automatic titrator equipped with a platinum complex electrode.
The potentiometric PV method gave a 10% higher value than by the official method of the Japan Oil Chemists' Society using isooctane (JOCS-I method) for samples with PV from 0.5 to 100 meq/kg. PV determined by the present method gave values quite consistent with those by the JOCS-Chloroform (JOCS-C) method.
Sample amounts in the JOCS-I method are 5 g for PV less than 10 meq/kg and 0.5 to 5 g for PV more than 10 meq/kg. By the present method, sample amounts were 2.0 to 5.0 g for PV less than 1 meq/kg, 0.1 to 2.0 g for PV from 1 to 100 meq/kg, and less than 0.1 g for PV more than 100 meq/kg. The present method is thus shown to have 5 times the sensitivity and accuracy of the official JOCS-I method. It is less time and labor consuming and oil/fat quality can be better controlled.
Any automatic titrator commercialized from 4 representative manufacturers in Japan may be used for the present potentiometric PV determination.

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The fate of sterylglycosides and alcohols as minor constituents in palm oil was investigated at different refining steps of physical (RBD) and chemical (NBD) refining processes using an HPLC method. The minor constituents included non-acylated (NASG) and acylated (ASG) sterylglycosides, and esters of phytol (PYH), dihydrophytol (DHP), geranylgenaniol (GG) and aliphatic alcohol (AA). The contents of these compounds were estimated for the used bleaching earths and deodorization distillates resulting from the two processes as well as in the soapstock from NBD. NASG and ASG were most effectively removed by alkali neutralization. Subsequent bleaching and deodorization process removed mostly residual sterylglycosides and alcohols. RBD processed oils contained higher amounts of ASG, which was considered to be a hypochloresterolemic substance, compared to NBD processed oils. These results indicated that the ASG level in palm oils could be used to differentiate between the RBD and NBD processes.

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Determination was made of phytosterol in the pollen of Typha latifolia L. The n-hexane-soluble fraction obtained from the methanol extract of the pollen was saponified and the unsaponifiable lipid was purified to obtain the fraction of phytosterol. This fraction was trimethylsilylated and analyzed by GC-MS. Six sterols, cholesterol, 24-methylenecholesterol, campesterol, stigmasterol, sitosterol, and isofucosterol, were identified. 24-Methylenecholesterol and isofucosterol are the major sterols in pollen, but T. latifolia pollen contains these sterols in only minor amounts, with β-sitosterol accounting for ca. 85% of total sterols.

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HLB temperature (or PIT) of octaoxyethylene dodecyl ether (C₁₂EO₈) in a water-decane system (81.5°C) has been shown to decrease with the addition of a lipophilic amphiphile such as monolaurin or 1-dodecanol. In the monolaurin system, HLB temperature decreased regardless of total surfactant concentration while in the 1-dodecanol system, increased to nearly resume that of C₁₂EO₈ with decrease total surfactant concentration. The difference in phase behavior may possibly be due to the solubility of lipophilic amphiphile in the oil phase.
The correlation of change in HLB temperature with HLB number is discussed for both systems.

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Lipase unit is defined as that amount of enzyme needed to produce 1 μmol non-esterified fatty acid in one minute under specified conditions. Non-esterified fatty acid is traditionally measured by acid-base titration. This was done in the present study in place of High-performance liquid chromatography (HPLC) method. HPLC with a light scattering detector was conducted to measure non-esterified fatty acids to determine the activity of lipase from Candida cylindracea. HPLC result was essentially the same as that obtained by titration, the former method being more sensitive.

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JIS K 3362 test method is designed for evaluating detergency of household laundry detergents. However, the reference detergent in the method contains 17% of sodium tripolyphosphate (STPP), whereas the most of the detergents in the current market are phosphate-free. In this study we tried to convert the JIS reference detergent into a phosphate-free formulation.
When whole STPP in the reference detergent was replaced by zeolite, the detergency became lower. However, after the addition of sodium carbonate for the compensation of the alkalinity of STPP, the detergency recovered to the initial level. Based on the results above, we propose the following formulation as a phosphate-free JIS reference detergent : sodium linear alkylbenzenesulfonate, 15%; zeolite, 17%; sodium silicate, 5%; sodium carbonate, 7%; sodium carboxymethyl-cellulose, 1%; sodium sulfate, balance.

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