The amount of used edible oil generated in Japan annually is presumed to be some hundred thousand tons. Half of it is rather easy to recover because it comes from food manufacturing industries, supermarkets, restaurants, and the like. Recovered oil of good quality is diverted for use as a fatty acid source or in the production of feed oil, paint, ink, fuel oil, soap, or other products, but the rest is burned or discarded. Stiff competition between the price of good-grade oil and the cost of refining low-grade oil is the principal reason for the insufficient reuse of recovered oil. The burning or discarding of large amounts of recovered oil in spite of a relatively low level of deterioration adversely affects the environment and promotes Japan’s dependency on imports. In this study, safe and inexpensive methods for refining used edible oil (Gardner color 11) to non-food industry oil (Gardner color<7) with possibly a small amount of factory waste were investigated. Refined oil with Gardner color 6 was prepared by a process consisting of filtration on an adsorbent and barium hydroxide or sodium hydroxide refinement. Barium hydroxide-refined oil was further bleached by hydrogen peroxide to obtain heat-stable reclaimed oil of Gardner color 3.
The crystallization of Palm Oil and its thermal features were examined in the present study by differential scanning calorimetry (DSC), X-ray diffractometry (XRD) and infrared spectroscopy (IR). The melting behavior of Palm Oil crystals was noted to differ significantly with temperature. One of the particular interest was the finding that small angle X-ray diffraction. Palm Oil crystallized when temperature was maintained at 10°C showed 65Å spacings. The IR absorption band due to the C-O-C group differed from any of those for samples obtained at other crystallization temperatures. It thus follows that the triple-chain length structure is present only in crystals obtained at 10°C and the double-chain length structure is to be found in those obtained at other temperatures. With heat application, the triple-chain length structure was noted to change to the double-chain length structure, this being accompanied by increase in enthalpy. Triacylglycerin in Palm Oil is comprised of POP (1,3-dipalmitoyl-2-oleoyl-glycerol) at about 30% and POO (1,2-dioleoyl-3-palmitoyl-glycerol) at about 20% and thus the present results would account for the varying triacylglycerin content in Palm Oil. Accordingly, when using Palm Oil-based products, attention should be directed to the effects of temperature on crystallization.
The sensitive analytical method by fluorescence spectrophotometer was developed for determination of trace amount of protein in oils and fats. Recoveries of spiked soybean protein powder into refined salad oils were 54 and 58% at the level of 1 and 5 ppm, respectively, and these coefficients of variation were 12 and 5%, respectively. The determination limit was 1ppm. Then residual proteins in fish oil and lard during the oil refining process were examined using this method. The protein concentrations were 6 ppm in crude fish oil and 22 ppm in lard. The amounts of protein markedly decreased at alkali refining and were lowered less than the determination limit at bleaching. Amounts of protein in 8 hydrogenated fish oils, 9 refined lard, 8 refined beef tallows, 3 refined soybean oils and 11 hydrogenated soybean oils, which are used for oils and fats products, were all less than the determination limit.
Aggregation behavior of sodium salt of mono-n-dodecyl phosphoric acid ester i.e. a species of mono-alkyl phosphate (MAP) surfactants, in pure water was investigated as a function of surfactant concentration (CS) by means of surface tension (γ), electroconductivity (measuring both specific (κ) and molar (Λ) conductivities), pH and UV-Vis spectra measurements. The Krafft temperature was determined as 40°C by observing the change of κ with raised temperature. Although the curve of γ vs. log CS plot gave only one break which corresponds to critical micellization concentration(CMC) in common theory, different relations of κ vs. CS, Λ vs. √CS, or κ vs. log CS, and pH vs. CS resulted in several breaks suggesting the occurrence of various transitions of aggregates or micelles over the concentration range not only above, but also below CMC. The CMC determined by surface tension measurement was referred to as the first CMC (CMC1). The critical concentrations of the transitions observed by various methods were termed as CACi (i=1,2,3) for three-step aggregate formation below CMC1 and as CMCj (j=1-5) for five-step transitions in micellar form. From the temperature study on CACi and CMCj, the estimated standard Gibbs energy changes were estimated, which showed us that the primary driving force of aggregate/micelle formation at any step comes from the entropy term, since the energy term (enthalpy) in this case was found to be positive. This supports our interpretation that the aggregates/micelles are mainly composed of hydrolyzed (protonated) mono-dodecyl phosphate molecules so that they behave as if they were nonionic surfactant micelles. A light scattering measurement verified the existence of aggregates formed below CMC. The experiment of catalytic activity assay revealed that SMDP aggregates formed in the low concentration range (ten times lower than CMC1) were found to act as catalysts for the hydrolysis reaction of p-nitrophenyl acetate (pNPA).
To utilize a typical squid processing by-product, hepatopancreas was enzymatically hydrolyzed, then subjected to a plastein reaction. The substrate concentration that gave the highest plastein yield was 30% by using Alkalase. The optimum pH for the plastein synthesis with Alkalase ranged from 6 to 9. The dominant molecular size of the formed plastein was about 2000. Alkalase mediated plastein reaction seemed beneficial for enriching aspartic acid and glutamic acid, and eliminating hydrophobic amino acids such as phenylalanine, tyrosine, leucine, and isoleucine. Despite the heat pretreatment, hydrolysate powder and plastein retained their antioxidative affect, but a discouraging drawback of the hydrolysate was an unacceptable stimulating taste. For this reason, plastein was considered to be a much better choice to use as an antioxidant because it was tasteless. Plastein from squid hepatopancreas may be a useful antioxidant because it is stable against heat, dissolves easily in water and suppresses the proxidative effect of metals on lipid oxidation.
The systematic studies through 1H NMR longitudinal relaxation times (T1) of an ionophoric 1,3-alternate-shaped calixarene ester 1 were reported. The T1 values were measured under proton-noise-decoupling conditions by the inversion-recovery technique. The terminal groups in an ethoxycarbonylmethoxybenzene unit in 1 move vigorously whereas the motion of the central ArCH2Ar moiety is rather suppressed. K+ ion plays an important role as a template ion specifically to freeze the fluctuational motion of these terminal groups. The ethoxycarbonylmethoxybenzene unit features a ‘seesaw motion’ around the ArCH2Ar moiety as central support. It is clear that the molecular motion of the calixarene skeleton is efficiently frozen through complexation with metal cations.