As a means of discriminating foreign fats in lard, cooling differential thermal analyses were carried out on lard, beef tallow, horse fat and mutton tallow, and lard mixed with beef tallow or horse fat. 1) Samples were melted at 70°C for 10 minutes and then chilled to -40°Cat the rate of 3°C/min. 2) Lard showed 34, beef tallow 2, and mutton tallow 2, exothermic perks. Horse fat showed 2 exothermic peaks in the temperature range examined but the peaks were smaller than those of other fats. 3) Presence of more than 5% of beef tallow in lard can be detected by the characteristic peak and the amount mixed can be known from the peak area. This is therefore more precise than heating DTA. 4) Presence of more than 20% of horse fat can be known from the characteristic peak and the ratio of peak area but this method is less precise than heating DTA.
Methyl acetate was pyrolyzed at 450, 500, 550, 600, 650, 700, 750 and 800°C, respectively, whose pyrolyzates were analyzed. This was difficult to decompose in the lower temperature range with the decomposition of only 44% at 650°C, while, in the higher range, the reaction advanced rapidly withh a maximum of more than 90% at 800°C. The principal products in the temperature range higher than 700°C were carbon monoxide and methane, and besides, considerable quantity of water, carbonn dioxide, acetone, methanol, acetic acid and formaldehyde were produced. Among these products, carbon monoxide, methane and formaldehyde increased in the quantity with rise of the pyrolysis temperature, whereas, water, acetone and methanol were produced in much quantity in the range up to 650°C, and they decreased at higher temperature than that.
In studying phase transition of fats and fatty compounds, a simultaneous measurement of X-ray diffraction and DTA is desirable. For such a purpose, a simple devise was designed in the -180°C+200°C range by modifying a low temperature X-ray diffractmeter attachment. Fig.-1 and Fig.-2 show outlines of this devise. With this devise, ammonium nitrate (Fig.-3), triglycerides, such as trilaurin (Fig.-4 E1), trimyristin (Fig.-4 E2), tripalmitin (Fig.-4 E3) and potassium laurate (Fig.-6, Fig.-7) were examined. Change in X-ray diffraction pattern coincided with DTA data. Even a small amount of heat of the transi-tion of ammonium nitrate (-16°C, 0.130 kcal/mol) was detected. It is expected that the transition accompanied with a hysteresis phenomenon will be successfully observed by this devise, because X-ray diffraction and DTA can be measured under entirely identical conditions.
Melting points of mixed samples of steryl (campesteryl and β-sitosteryl ferulates, 46 : 54 (wt%)), cycloartenyl, 24-methylene cycloartanyl ferulates were studied. A mixture of cycloartenyl and steryl ferulates, 52 : 48 (wt%) showed a minimum of melting point as the eutective type. Also, a minimum melting point as the eutective type was observed at a mixture of 24-methylene-cycloartanyl and steryl ferulates, 25 : 75 (wt%). The isothermals were made from the melting points of the mixtures of steryl, cycloartenyl and 24-methylene-cycloartanyl ferulates. The heat stability of the mixture of four kinds of ferulate was investigated. Four samples of the mixture were heated for 8 hours at 120, 195 and 240°C and for five minutes at 350°C, respectively. The heated samples were analysed by thin-layer chromatography and ultraviolet absorption spectra. Unchanged ferulates in heated samples were separated and saponified. The unsaponifiable matters of unchanged ferulates were analysed by gas chromatography to estimate the compositions of the unchanged ferulates. The order of heat stabilities of the ferulates was considered as follows : campesteryl ferulate > β-sitosteryl ferulate > cycloartenyl ferulate > 24-methylene-cycloartenyl f erulate.
As cationic surfactants are readily precipitated into reineckates, identification of 27 cationic surfactants of various types and different chain lengths were attempted with the methods of infrared spectroscopy and paper chromatography. Surfactant reineckates were prepared as follows ; 1% aqueous ammonium reineckate solution was added into 2% aqueous (or ethanol) solution of surfactants. Infrared spectra were obtained by potassium bromide disc technique, and the solvent system in paper chromatography was methanol : water : 35% hydrochloric acid (12 : 12 : 1). Surfactants used for the present experiment were separated into the following three groups ; group A : amines and quaternary ammonium salts, group B : surfactants of pyridine ring, and group C : amphoteric surfactants, which have characteristic infrared absorption bands. Each group could be differentiated and surfactants in three groups could be identified by infrared technique. Both the absorption bands of surfactants (7001, 800 cm-1) and those of reinecke ion (3, 0003, 500 cm-1) in infrared spectra of surfactant reineckates could be used in the identification of surfactants. Alkyl chain lengths could be differentiated with paper chromatography, but in this case, surfactant reineckates were treated with silver nitrate. Rf values of C12, C14, C16 and C18 except for primary amines were 0.680.78, 0.390.50, 0.170.21and 0.000.06 respectively.
Seed oils from two species of cucurbitaceae (Kikarasu-uri and Prince melon) were investigated on their general properties, the fatty acid compositions determined by gas chromatography and on the characteristics of unsaponifiable matters. The oils were obtained by extracting the dried seeds with ether. The general properties were as follows ; Kikarasu-uri (d24 4 0.9235, n22D 1.4555, I.V. 121.5, S.V. 210.5), Prince melon (d184 0.9180, n18D 1.4765, I.V. 135.1, A.V. 3.5, S.V. 190.7). > The fatty acid compositions were C12 : 0, 1.8; C12 : 1, 1.5; C14 : 0, 0.8; C14 : 1, 0.9; C16 : 0, 5.7; C18 : 1, 17.0; C18 : 2, 44.7; C18 : 3, 3.3; C20 : 0, 6.1; C20 : 1, 15.8 and C20 : 2, 2.4 in the case of Kikarasu-uri, and C12 : 00.6; C12 : 1, 0.7;C14 : 0, 0.5;C14 : 1, 0.2; C16 : 0, 9.1;C16 : 1, 1.8; C18 : 1, 10.2; C18 : 2, 60.9; C18 : 3, 1.7; C20 : 1, 2.9 and C20 : 2, 11.4 in the case of Prince melon. The main sterols in unsaponifiable matters of Kikarasu-uri and Prince melon were considered to be brassicasterol and poriferasterol, respectively.
1) Changes in the melting point and S.F.I. values at 20°C were examined during a period of one year with 19 kinds of household margarine, 10 kinds of bakery margarine and 10 kinds of shortening. Maximum, minimum average, and R values of these were also calculated. Hardness, oil-off value and S.F.I., were measured on five characteristic brands of household margarine and one brand of butter manufactured in summer, winter, spring and autumn. 2) Average melting point of household margarine was 33.1°C and R 8.1°C, while those of bakery margarine were 35.1°C, and R 11.2°C, and those of shorting were 37.8°C and R 10.8°C. 3) Average of S.F.I. values were 19.4 and R 14.1 for household margarine, 18.7 and R 8.9 for bakery margarine, and 19.5 and R 17.8 for shortening, indicating that the R values did not necessarily agree with R values for the melting point. 4) Six of the household margarine showed almost no difference in the melting point and S.F.I. value throughout the year, and there were nearly no changes in their physical properties or fatty acid composition. The parchment wrapped margarine showed a high melting point throughout the year, while spread margarine sold by scale showed a marked difference between summer and winter. 5) There was found a correlation between the melting point and S.F.I. or iodine value, with a fairly high correlation coefficient. A correlation was also found to exist between F2 + F3 and melting point or S.F.I.