The food industries in Japan ban used edible oil in the amount of some hundred thousand tons every year. The color deterioration of the oil used for frying in the industries, and recovered on a large scale, was investigated. Virgin frying oil, whose mineral content was adjusted to that of recovered oil, was spiked with several components of fried foods (separately and in combination), then heated at 180°C for up to 70 h. From the change in oil viscosity, the apparent heating time of recovered oil was judged to be 20 h. It was found that in practice, starch, proteins, sugar, and pigments had little to do with the deterioration, whereas the amino acids, especially Cys, Met, Trp and the oil itself contributed to the deterioration. These amino acids seem to be exuded from foodstuffs during frying. The level of minerals in the oil affected the deterioration and viscosity increase of oil itself, in rate as well as in degree although the deterioration by amino acids was not affected much by mineral content. In conclusion, it is suggested that color deterioration of frying oil used in the Japanese food industry is attributable to (i) the amino-carbonyl reaction between thermally oxidized oil and amino acids exuded by fried stuffs, and (ii) coloring of oil itself influenced much by mineral content.
The title parameter was measured by the AgNO3-TLC / GC method and the results were compared with those for margarines produced in France and the United Kingdom (UK). 1) Trans fatty acid content in domestic margarines were expressed as the following percentages of total fatty acids, print type, 2.9-22.4% (average 13.4%); soft type 1.1-17.0% (average 9.9%); prepared margarines, 8.0-9.7% (average 8.9%); fat spreads, 0.6-11.8% (average 8.2%) and flavored and sweetened fat spreads, 3.6-11.3% (average 7.5%). In French margarines, print type and soft type contained trans fatty acid at 0.6-1.1% (average 0.9%) and 0.7-2.1 (average 1.0%), respectively. UK soft type margarines contained 0.3-13.3% (average 2.5%) trans fatty acid. 2) To determine the effects of world-wide legal regulations that limit trans fatty acid intake, change in content of trans fatty acid was compared for domestic margarines produced in 2003 and 2004. No change could be detected in trans fatty or saturated fatty acid and linoleic acid content for the two periods. 3) Trans fatty acid content in domestic and UK margarines was compared for 1996 and 2003 in both periods, trans fatty acid content in domestic margarines was bound to decrease by 10% in tub type and in UK margarines 70%, indicating a more rapid response to lower trans fatty acid in UK compared to Japan. 4) Total saturated and trans fatty acid content (TFA+SFA) in margarines from Japan, France and UK was essentially the same.
In the present paper lipase catalyzed synthesis of Diacylglycerol (DAG) and Monoacylglycerol (MAG) by esterification of glycerol and Oleic acid in an organic solvent was studied, and optimal conditions for acylglycerols synthesis by enzyme were established. Suitable biocatalysts were chosen on the basis of systematic screening experiments regarding their regio-selectivity, substrate tolerance. Lipases investigated were Rhizomucor miehei (RMIM) and Thermomyces lanuginosa (TLIM), which gave highest degree of esterification. The selective enzymatic production of Mono and Di-Olein (MO, DO) was optimized to obtain maximum yields. Hexane was useful organic solvent in glycerides synthesis. Based on this experiment, acylglycerols were synthesized on a preparative scale in good yields (>90%).
Sodium-23 NMR longitudinal magnetization recovery (L.M.R.) study has been carried out to clarify the sodium ion exchange in ensembles with 1,3-alternate-shaped calixarene 1 for the first time. The line width υ1/2 of a sharp singlet for NaClO4 in the absence of 1 is 65 Hz: upon addition of 1 a singlet peak was broadened to 1100 Hz (υ1/2). The life times (τ) of Na+ were estimated to be (20-3.8)×10-3 s for τA and (5.0-2.0)×10-3 s for τB, by the simulations of sodium-23 NMR L.M.R. curves. The life times of 1-Na+Ensemble are larger than those for 18-crown-6. This implies that Na+ cation is bound deeply in the cavity formed by two OCH2CO groups of 1, the complex being classified as a “nest-in-type”.
The carbon-13 NMR longitudinal relaxation times (T1) studies on the 1,3-alternate-shaped calixarene possessing two ester groups 1 in the absence and the presence of Na+ were carried out for the first time. The T1 values were measured under proton-noise-decoupling conditions by the inversion-recovery technique. The T1-value of 1 is primarily governed by dipole-dipole relaxation. When calixarene 1 forms an ensemble with Na+, the T1-values for all carbons are decreased. This suggests that the molecular motion of species 1 is efficiently frozen through complexation with Na+. Eventually, Na+ ion plays an important role as a template ion specifically to freeze the fluctuational motion of two ethoxycarbonylmethoxybenzene units of 1.
Large amounts of procyanidins, made up of catechin oligomers, are consumed on a daily basis via various plant-based diets. Recent studies show that tea polyphenol (TP) exerts anti-obesity effect; however, the biological functions of procyanidins have not yet been established. In this study, we examined the high dose effects of procyanidins from apple polyphenol (AP), hop polyphenol (HP), and tea polyphenol (TP) on obesity using normal Sprague-Dawley rats on a high fat (HF) diet. We measured adipose tissue mass and tissue lipid parameters in rats on polyphenol-free low fat (LF) (7%) or HF (27.8%) diets with or without 1% of each polyphenol for 9 weeks. Dietary AP, HP, and TP suppressed the increase in white adipose tissue. Dietary TP increased the level of fatty acids excreted into feces; however, this was not observed in the AP- or HP-fed group. Each dietary polyphenol tended to reduce fatty acid synthesis and promote fatty acid β-oxidation as compared with a HF diet alone. Moreover, each dietary polyphenol tended to increase the level of peroxisome proliferator-activated receptor alpha (PPARα) in the liver and decreased the levels of PPARγ in brown and white adipose tissues. Therefore, we speculate that procyanidins from AP or HP may reduce the increase in white adipose tissue induced by an HF diet through a combination of the agonist-like action of PPARα and antagonist-like action of PPARγ. On the other hand, TP may exert an anti-obesity effect via the combined effect of PPARα and PPARγ described above as well as the promotion of fatty acid excretion into feces.
A convenient - and quick to realize - approach for the synthesis of tetrabutylammonium hexachlorometalates (Bu4N)2[MCl6] is suggested. Since the preparation of (Bu4N)2[MCl6] (M=Re, Os, Ir) by simple one-pot method is hitherto unreported, we successfully synthesized it by simply mixing the tetrabutylammonium hydroxide with acidic solution of potassium salt of hexachlorometalates.