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The polymorphism of 25 glycerol trioctadecenoates with double bonds ranging from Δ4-Δ17 was investigated by differential scanning calorimetry. Triglycerides withcis bonds in odd positions Δ7-Δ13 exhibited three intermediate melting (β′-) forms, but those withcis bonds in even positions, exceptcis Δ4, lacked β′-forms. Among thetrans compounds, only Δ11, 13, and 14 showed β′-forms. Thecis andtrans Δ5 triglycerides were unusual, because they readily assumed low melting (α-) forms that were not easily converted to high melting (β-) forms. β-Form mp of compounds in each series (cis ortrans) alternated depending upon double bond position; an even position correlated with high mp. Heats of fusion (ΔHf) for β-forms, likewise, fluctuated with double bond position but nonuniformly;trans Δ6 had the highest ΔHf (43 cal/g),cis Δ12 the lowest (21 cal/g).

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Both liquid and solid surface-active adducts of brassylic (tridecanedioic) acid were prepared by potassium hydroxide-catalyzed addition of ethylene oxide gas to the molten acid. The number-average molecular weights $$\left( {\overline {MW} _n } \right)$$ of the adducts ranged from 500 to 3,000. These adducts cover a wide span in the ratios of hydrophilic to lipophilic portions of the molecule. They are unique in that hydrophilic end-groups sandwich a rather long chain of lipophilic methylene units. Treatment of some adducts with hot, saturated, aqueous sodium chloride induced transesterification and produced hydroxyl-terminated, multi-brassylic, poly(ethylene glycol) esters of MWn 1,000 to 4,000, all of which were efficient surface-active agents. Average degrees of polymerization of the poly(ethylene oxide) (PEO) chains were determined by a) functional group analysis, b) weight increase, and c) methanolysis of the products, followed by gas-chromatographic analysis of the isolated poly(ethylene glycol) fraction. Surface tension, critical micelle concentration, emulsion stability, and efficiency as an emulsifying agent in the aqueous polymerization of vinyl acetate were measured to evaluate surfactant properties of products in which the degrees of polymerization of the PEO chains ranged from 1.4 to 44.

Coriolic [(R)-13-hydroxy-cis-9,trans-11-octadecadienoic] acid (III, R=Z=H) was isolated as the methyl ester from twoCoriaria seed oils in 66 and 68% yields. The double bonds and hydroxyl group were located by periodate-permanganate oxidation before, and chromic acid oxidation after, hydrogenation of the double bonds. Alternatively the positions of the functional groups were indicated by a convenient micro-ozonolysis-gas-liquid chromatographic procedure. Determination of products from partial hydrolysis of theCoriaria oils with pancreatic lipase (EC 3.1.1.3) revealed a preference of the corioloyl group for the 1,3-positions in triglyceride molecules. The possible significance of coriolic acid as an intermediate in the biogenetic conversion of linoleic acid to conjugated trienoic acids is discussed.

A convenient and rapid procedure involving methylation, silylation, and temperature-programmed gas-liquid chromatography (GLC) is described for analyzing unfractionated products from the hydrolysis of triglycerides with pancreatic lipase. The conditions employed for GLC were selected to provide maximum and rapid separation of silylated monoglycerides in which the acyl moieties differ in chain length or degree of substitution with oxygen-containing functional groups. Derivatives differing only in the number of double bonds present were not separated. In the GLC curves obtained, peaks representing methyl esters are generally readily distinguishable from those of other components. Therefore, the extent of lipolysis and the composition (with respect to chain length and substitution of acyl groups) of monoglycerides formed are determined simultaneously. The accuracy of the new method was demonstrated with standard mixtures and by comparison of results for several lipolysis products with data obtained by conventional procedures.

Brockerhoff-type procedures were used to determine the amounts of each acyl group at each glyceride position ofLimnanthes douglasii seed oil. During the course of the analyses, small quantities of three acids isomeric with those previously found in the oil were identified by their ozonolysis products and their gas-liquid chromatographic (GLC) behavior. The newly discovered constituents of the oil were 3-octadecenoic acid (0.1%), 5-octadecenoic acid (0.9%) and 11-eicosenoic acid (3%). The saturated acids and those with ω-9-unsaturation are esterified most often to β-glyceride positions inLimnanthes seed, while the acids with Δ5-unsaturation occur generally at the outer glyceride positions. Although the Δ5-unsaturated acids as a group exhibited no obvious preference for one outer position over the other, individual acids were unequally distributed between the 1- and 3-sn-glycerol positions. The probabilities of occurrence of the various triglycerides were calculated from the stereospecific analysis data by assuming a 1-random, 2-random, 3-random distribution of the acyl groups. The calculations are in agreement with the composition of the whole oil, as determined by GLC.

The polymorphism of 13 single acid triglycerides with acyl group chain lengths ranging from 16–22 was studied by differential scanning calorimetry. In contrast to the singleβ′-form generally attributed to such triglycerides, at least two intermediate endotherms were found for most samples between the least stable (α) and most stable (β) polymorphs. For saturated triglycerides, two versions of the familiar “tuning fork” model meet theβ′-form requirement of alternate fatty acid chains in planes perpendicular to each other. The detection of three intermediate endotherms for triolein, tri-cis-1 1-octadecenoin and trierucin (and possibly also trilinolein) may be rationalized by assuming that the segments of polymethylene chains on either side of double bonds may zigzag in different planes. Four exceptions for which no evidence was found forβ′-forms are tri-cis-6-octadecenoin, tri-cis-6-hexadecenoin, tri-trans-6-octadecenoin and trielaidin. Three of these exceptions contain Δ6-acyl groups and have in common segments with even numbers of methylene groups on either side of the double bonds. These same three triglycerides also have a shorter than usual polymethylene segment between the ester linkages and the double bonds and a longer than usual distance from the double bonds to the terminal methyl groups. Tri-trans-6-octadecenoin and trielaidin are exceptional in still another way. Only they and are exceptional in still another way. Only they and trierucin exhibited significant nonconformity with an empirical relationship between melting points and heats of fusion ofβ-forms. Otherwise, all points in a plot of the former physical constants vs. the latter closely fit a smooth curve, the positive slope of which gets larger as the X-axis values, i.e., melting points, increase.

When defatted seed from Brassica napus L. var. Regina II (a rapeseed) was autolyzed, its major thioglucoside (progoitrin) underwent degradation analogous to that for epiprogoitrin in Crambe abyssinica seed meal. Depending on the conditions, (R)-1-cyano-2-hydroxy-3-butene and the diastereomeric forms of (2R)-1-cyano-2-hydroxy-3,4-epithiobutane were formed in autolyzed B. napus meal instead of (S)-goitrin. The configuration at the chiral center containing the hydroxyl is assigned on the basis of known data. The configuration at carbon 3 of the episulfides is predicted on the basis of the optical rotatory dispersion data.

Diallyl brassylate (DAB), a new monomer, and diallyl azelate (DAA) were converted to new prepolymers for comparison with analogous commercial products from diallyl o-and m-phthalate (DAMP). Respective prepolymers from DAB and DAA had Mn 28,000 and 40,000 and contained approximately 0.8 free allyl moiety per repeating unit. Only the DAB prepolymer exhibited crystallinity at low temperatures as detected by differential scanning calorimetry and x-ray diffraction. Aliphatic prepolymers have greater heat stability than aromatic ones and evolve fewer calories per double bond during curing than reported for DAMP prepolymer. Low shrinkage (

Gas liquid chromatography of winterized sperm oil showed that its wax esters with even carbon numbers range from C24 to C42 and are present in quantities resembling a normal distribution curve with C34 as the mean. Between these even-numbered wax esters, ones with odd chain lengths were eluted. Triglycerides, similarly present in a normal distribution pattern, ranged from C42 to C58 and also included traces of odd chain species. The component acids and alcohols were analyzed by gas chromatography-mass spectrometry, and double bond positions in the monoenoid components were established. Branched chain and odd chain constituents, both saturated and unsaturated, were detected among both alcohols and acids. These moieties, when combined with those having even chains, are responsible for the wax esters and triglycerides with odd carbon numbers.

Because of evidence that erucic acid may be undesirable in edible products, genetically developed low-erucic varieties ofBrassica campestris andBrassica napus are expected to become a major part of the Canadian and European rapeseed crops within the next few years. In contrast the objective of work on crambe and related oilseeds in the U.S. is a reliable domestic source of oil high in erucic acid for industrial purposes. Whether the oil is produced for edible or nonfood uses, however, the glucosinolates that are characteristically present in oilseeds of the mustard family unfavorably influence the use of the byproduct meals as feed. These glucosinolates are the subject of current intensive research, both chemical and genetic. Development of convenient, accurate and sensitive analytical methods has markedly facilitated this research. To achieve optimum meal quality, procedures involving aqueous extraction of unreacted glucosinolates are under study. Genetically, a Polish variety ofB. napus called Bronowski has been found to produce seed having very low glucosinolate content, and individual low-glucosinolate plants ofB. campestris have been discovered. Crambe exhibits significantly less observable variability than rapeseed. Consequently the approaches based on chemical research seem more promising, but the possibility of developing a low-glucosinolate, high-erucicBrassica adapted to agricultural production in the U.S. to complement or even compete with crambe is not being overlooked.

New high-epoxy vegetable oils from nine species representing three plant families and four genera have been investigated. The epoxyacyl moiety in at least one oil from each genus was characterized and shown to be the (+)-vernoloyl (cis-12,13-epoxy-cis-9-octadecenoyl) group. Intraglyceride distribution studies revealed a general preference of the (+)-vernoloyl groups for the beta-position of triglyceride molecules. Interglyceride distribution of (+)-vernoloyl groups was studied in three oils and found not to agree with predictions based on either 1,2,3-random or 1,3-random-2-random distribution. A striking exception to the general intraglyceride distribution pattern was discovered in the monoepoxy triglyceride fraction fromEuphorbia lagascae seed oil.

A computerized version of the Fineman-Ross linearization procedure was used to determine reactivity ratios for copolymerization of vinyl chloride (monomer 1) and 2-methylpentyl vinyl brassylate (monomer 2). From differential refractometry data for the products of low-conversion copolymerization, the procedure gave r1 = 1.06 and r2 = 0.234. The ratios computed from chlorine contents of the same products were r1 = 1.10 and r2 = 0.239. The polarity factor (e2) and general monomer reactivity (Q2) calculated for monomer 2 from these ratios were, respectively, −0.95 to −0.98 and 0.032–0.033. The interquartile range for the copolymerization of a mixture of 60% monomer 1 and 40% monomer 2 was 1.4%. These values suggest that from suitable proportions of reactants, sufficiently homogeneous distribution of monomers can be achieved in copolymers of vinyl chloride and 2-methylpentyl vinyl brassylate to offer the possibility of effective internal plasticization.

Triglycerides containing acids withtrans-3 unsaturation (16∶13, 18∶13 and 18∶33, 9, 12) showed a marked retardation of reaction rate with pancreatic lipase. An inverse relationship was found between content oftrans-3 unsaturated acids in seed oils and lipolysis rate. Thetrans-3 unsaturated acids were concentrated in the diglyceride and residual triglyceride fractions of the lipolysates, and only small amounts were present in the free acid and monoglyceride fractions.

A convenient and rapid procedure involving methylation, silylation, and temperature-programmed gas-liquid chromatography (GLC) is described for analyzing unfractionated products from the hydrolysis of triglycerides with pancreatic lipase. The conditions employed for GLC were selected to provide maximum and rapid separation of silylated monoglycerides in which the acyl moieties differ in chain length or degree of substitution with oxygen-containing functional groups. Derivatives differing only in the number of double bonds present were not separated. In the GLC curves obtained, peaks representing methyl esters are generally readily distinguishable from those of other components. Therefore, the extent of lipolysis and the composition (with respect to chain length and substitution of acyl groups) of monoglycerides formed are determined simultaneously. The accuracy of the new method was demonstrated with standard mixtures and by comparison of results for several lipolysis products with data obtained by conventional procedures.

When bis(trimethylsilyl)acetamide is used to silylate lipolysates for gas-liquid chromatography, the pyridine solution containing the sample and silylating agent can be injected directly onto the column. Conversion of free fatty acids to methyl esters before silylation is unnecessary, since silyl esters elute as sharp gas-liquid chromatographic peaks.

Eight potential new sources of vegetable proteins were described in short presentations; texts of 11 are reproduced in these Proceedings. Discussion of Hagenmaeier's paper on Experimental Coconut Protein Products pertained to his statement about the added cost involved in producing defatted flour from this source. The increased cost is largely attributable to capital investment required for extraction equipment, and the question is whether or not this investment might not be more than repaid in the long run by the value of the oil recovered. Potatoes offer a particularly intriguing potential new source of protein concentrates and isolates. Development of such products from this crop, which yields more protein per acre per year than any other plant species so far domesticated, was discussed by Meuser of the Technische Universitat Berlin. He called at tention to the possibility of exploiting a by-product from the potato starch industry and at the same time helping to solve a pollution problem. Water from the first processing step in the manufacture of two million tons per year of potato starch contains 100,000 tons of protein. If diverted before further dilution in subsequent processing steps, this solution can be treated by direct steam injection to coagulate half of the dissolved protein. The resulting precipitate contains 80-85% protein, which is 8% lysine and 2.6% methionine. Dr. Meuser passed around samples of this "concentrate" and a 95% potato protein isolate prepared from it in his laboratory. Among problems to be overcome are pronounced "cooked-potato" flavor and odor notes and "horny" protein particles that cause a sandy mouthfeel. The third paper in this Round Table Discussion dealt with field peas and broad beans. Apropos of the feasibility of the latter source, at tention was called to the relevance of information about favism given by Dr. Liener in Plenary Session H. Vicia faba proponents emphasized that susceptibility to this malady is very limited. Cited as an example was the fact that canned broad beans have been marketed for several years in Canada, and only seven confirmed cases of favism have been documented there. Table III of Dr. Betschart's paper shows projected costto-make data for safflower protein isolates lower than those for soy protein isolates. In her oral presentation, she emphasized that her cost estimates were tentative and approximate. She concluded with the observation-referred to be several later discussants-that acceptance of any new oilseed protein depends on social and political as well as nutrit ional factors. The value of by-product oil is apt to be a major factor in the future of Lupine proteins for human consumption. Similarly, effectiveness and economic feasibility of removing polyphenolic constituents will be critical in the case of grapeseed. Good agronomic aspects and a protein content with amino acid spectrum complementary to that of soy protein are strong points favoring sesame as a potential new protein source. A series of papers on leaf proteins was initiated by an overview prepared by N.W. Pirie of the University of Reading and read by Dr. Lusas. This paper contains a statement to the effect that there is little prospect of popularizing a leaf protein in a particular communi ty unless the people there already eat the plant in question as a leafy vegetable. The discussion group did not feel as strongly as Dr. Pirie about this. All three originally scheduled papers on leaf protein reflected general optimism about their future. At Chairman Lusas' request, Kinsella of Cornell University (first speaker in Plenary Session D) made some impromptu remarks to put this optimism in perspective. Afterwards he submitted the accompanying printed statement. In his oral remarks he made the following points