A review on 56 original papers for the 23th Japan Oil Chemists' Society Award is presented. Relations between foaming tendencies and chemical and physical properties of frying oil, mechanism of colour development of frying oil and volatile products of edible oils by open air heating are described. In relation with the preventions of deteriorations of frying oil, functions of silicone oil in frying oil are discussed. Relationship between rancid flavor of edible oils and their fatty acid composition and simple methods for determining the volatile carbonyl value are described. Changes in fatty acid composition during the drying and smoking of pacific saury and the cookings of coho salmon are described.
Volatile oils of black soybeans (a kind of Glycine max Merrill) were prepared from beans (VKA), and boiled beans with sucrose (VKB) by steam distillation. GC and GC-MS analyses were then conducted. Seventy-five components were definitely or tentatively identified, and were revealed to include 18 hydrocarbons, 21 alcohols and phenols, 9 aldehydes, 3 ketones and 16 acids in VKA. Eighty components such as 27 hydrocarbons, 18 alcohols and phenols, 9 aldehydes, 2 ketones and 16 acids were included in VKB. The characteristic volatile flavor components of VKA, were 2-ethylhexanal (ca. 20%), 4-vinylguaiacol, hexadecanoic acid and maltol, and in VKB were 4-vinylguaiacol (ca. 3%), hexadecanoic acid, maltol and guaiacol. The compositional characteristic of VKB was predominantly large amounts of esters, hydrocarbons and aromatic compounds compared with VKA.
The reduction of nitrosobenzene with methanol in the presence of potassium hydroxide was studied spectrophotometrically. The reaction in the absence of potassium hydroxide was inhibited by galvinoxyl. It gave azoxybenzene and formaldehyde cleanly and its rate could be expressed as follows : Rate=κ2CNSB2 The rate equation in the presence of potassium hydroxide was found to be : Rate (KOH) = (κ2+κ3COH-/CH2O) CNSB2 The reaction had an induction period, and maximum conversion did not attain 100%. Besides azoxybenzene and formaldehyde, other products such as aniline, azobenzene, formic acid, and phenylhydroxylamine were detected in the latter reaction. Moreover, these by-products were formed even during the induction period. Both the percentages of main product loss and the induction period were proportional to the concentration of potassium hydroxide. The reaction in the presence of potassium methoxide and in the absence of water had no induction period and formed the four by-products. The induction period and formation of the four by-products under alkaline condition may possibly have been due to hydroxide ion. Probable mechanisms for the radical reaction of azoxybenzene formation involving dimerization of phenylhydroxylamino radical, and for the ionic reaction of by-products formation initiated by hydroxide ion are presented and discussed.
We studied the effects of seeding several fat crystal powders on the viscosity of dark chocolate, so as to apply this technique to industrial chocolate production. The highest limit of seeding temperature, above which there was no seeding effect in 10 minutes incubation, was compared to improve fat bloom stability. As seed materials, Form V and Form VI of cocoa butter, β2 and β1 of 1, 3-distearoyl-2-oleoylglycerol (SOS), and β2 of 1, 3-dibehenoyl-2-oleoylglycerol (BOB) were used. All the crystals were pulverized to fine powders of 2070 μm below -60°C. The viscosity of supercooled molten dark chocolate was measured, before and after seeding, with a rotational viscometer at 30°C. The concentrations of the seed crystals were 1 and 5 wt%. Both forms of cocoa butter as well as SOS remarkably increased viscosity just after seeding. The seeded dark chocolate showed no increase in viscosity for 12 minutes after seeding BOB β2 powders even at a concentration of 5 wt%. The seeding temperature was highest for BOB β2 (38°C), among the five seed powder. Fat bloom stability was greatest in BOB β2. The most favorable seed material was thus concluded to be BOB β2.
Amphiphilic monoaza crown compounds (2 a-f) and diaza crown compounds (3 b and 4 a-c) bearing side chains with cation-binding ability were prepared by the method shown in Scheme-1. Cloud points, complexing stability constants (log K'1) with alkali metal cations (Na+ and K+) in methanol, and phase-transfer catalytic activity were examined for the products, and the data were compared with those of reference compounds. Among amphiphiles having almost the same HLB (Hydrophile-Lipophile Balance), cloud point height was in order of (5) > (2) > (3 b), (4). This was explained as due to the structural effects of two hydrocarbon chains in the hydrophilic moiety of the surfactants. The cloud points of (2), (3 b) and (4) increased by the addition of an alkali metal salts (NaCl or KCl) as reported in the case of (5). The stability constants (log K'1) of (2) were lower than those of (5) with the same number of ether oxygen atoms, and log K'1 increased with the number of ether oxygens in each series. Log K'1 of diaza crown ether series (3 b, 4 a-c) was reduced by the introduction of ether oxygens. Depending on the reagent used (NaI or KI), (2) and (4) exhibited higher phase-transfer catalytic efficiencies than those of the reference compounds (5 d) and (7). These efficiencies may be closely related to both log K'1 and HLB of the complexes composed of azacrown compounds and the reagents.
The binding of steroidhormones to bovine serum proteins was examined so as to explain the transport behavior of steroidhormones by proteins in serum. The affinities of bovine serum proteins prepared by Cohn's separation method with six kinds of steroidhormones (α-estradiol, ethynylestradiol, progesterone, androsterone, dehydroisoandrosterone and testosterone) were measured from partition experimental results. The affinity of Cohn's fraction III with hormones was not observed, but binding to fraction IV-1 and V (albumin) was clearly evident. When these hormones were added exogenously, binding coefficients K (protein-binding form/free form) in 3.5% bovine serum albumin (BSA) solution were 4080% of those noted in bovine serum containing the same amount of albumin. The effect of the binding of free fatty acid (FFA : C14 : 0, C16 : 0, C18 : 0, C18 : 1 and C18 : 2) with BSA on the affinity of BSA to steroidhormones was also investigated. Change in affinity could not be clearly detected for α-estradiol, ethynylestradiol or dehydroisoandrosterone, but a distinct increase was observed for progesterone, androsterone and testosterone following the addition of FFA. The binding coefficients of the latter three hormones increased by 5060% beyond that of the repeated control without the addition of FFA.
Aliphatic amines have been produced since long ago and are used for making products, such as fabric softeners, antistatic agents, shampoos, conditioners, and others. Aliphatic amines can be produced by many methods. Among them, the reaction of an aliphatic alcohol with a primary amine gives dialkylamine. We have already reported that the Cu-Ni catalyst provides high activity and selectivity for the reaction between dodecyl alcohol and dodecylamine. The reaction mechanism for the formation of didodecylamine from dodecyl alcohol and dodecylamine is considered to be as follows. Dodecyl alcohol is dehydrogenated to form the corresponding aldehyde (first step) which reacts with dodecylamine to give the reaction intermediate (second step). This intermediate undergoes conversion to didocecylamine by hydrogenolysis (third step). In this study the titration curves of products during reaction between dodecyl alcohol and dodecylamine were each found to have two equivalence points. It would thus appear that there is another product giving an equivalence point differing from that of the objective product (didodecylamine) or the raw material (dodecylamine). This product was sought using FT-NMR, and found to be didodecylimine. From these results, the following new mechanism is put forth. Dodecyl alcohol is dehydrogenated to the corresponding aldehyde (first step) which reacts with dodecylamine to give the reaction intermediate (second step). This intermediate subsequently undergoes dehydration to form didodecylimine (third step). Didodecylimine is then hydrogenated to give didodecylamine (fourth step).
In the two-step process for manufacturing cyclohexanol via cyclohexene from benzene, the procedure for effectively hydrating cyclohexene only in a reaction mixture obtained by partial hydrogenation of benzene is very important. This is because separating cyclohexene from the reaction mixture obtained in the first step is much more difficult than recovering benzene and cyclohexane after converting cyclohexene to cyclohexanol in the second step. Therefore, we investigated the optimum hydration conditions to obtaind cyclohexanol from a mixture using sulfuric acid and an additive. At a reaction temperature below 30°C, both the hydration rate and cyclohexanol yield decreased with lowering of the temperature. At a temperature over 30°C, the sulfonation of benzene and polymerization of cyclohexene easily occurred. Essentially the same was observed at the concentration and amount of sulfuric acid. Thus, the optimum temperature, sulfuric acid concentration and the used hydration were 30°C, 75%, and 2.7 mole to 1 mole of cyclohexene, respectively. As additives all metal salts were effective, but no alcohol used at this stage promoted cyclohexanol formation. The best additive was nickel sulfate. When a mixture of benzene (0.05mol), cyclohexene (0.15mol) and cyclohexane (0.3mol) was treated with 75% sulfuric acid (0.4mol) in the presence of nickel sulfate (0.01mol) at 30°C for 35h, the cyclohexanol yield was about 80%.