Method for characterization of triacylglycerols and fat-soluble vitamins in edible oils and fats by supercritical fluid chromatography

This study demonstrates the usefulness of capillary supercritical fluid chromatography (SFC) for the characterization of triacylglycerols of edible oils and fats. Triacylglycerols were separated according to the acyl carbon number and the degree of unsaturation on a 25% cyanopropyl/25% phenyl/50% methylpolysiloxane stationary phase. Valuable information concerning the triacylglycerol composition of berry oils was obtained, despite the overlapping of certain triacylglycerol peaks. Simultaneous analysis of fat-soluble vitamins and triacylglycerols is not practical by capillary SFC with flame-ionization detection because of the low concentration of naturally-occurring fat-soluble vitamins in edible oils. Therefore, higher loading of the sample, which led to overloading of triacylglycerols, was required to get reasonable peaks for fat-soluble vitamins. The method was applied to the characterization of triacylglycerols and tocopherols in sea buckthorn pulp and seed oil, and cloudberry seed oil without any sample purification prior to SFC. In addition, the stationary phase proved useful for separating the more complex mixtures of triacylglycerols found in milk fat and in fish oil.     

Separation of γ- and α-linolenic acid containing triacylglycerols by capillary supercritical fluid chromatography

The separation of γ- and α-linolenic acid containing triacylglycerols with an identical acyl carbon number and degree of unsaturation was obtained on capillary supercritical fluid chromatography using a 25% cyanopropyl−75% methylpolysiloxane stationary phase. The resolution of 1,3-dioleoyl-2-γ-linolenoyl-sn-glycerol and 1,3-dioleoyl-2α-linolenoyl-sn-glycerol was 1.35 on a 10 m×50 μm i.d. column, whereas the resolution was enhanced to 1.66 by combining two 10-meter columns in series. The difference in the position of double bonds in one linolenic acid residue of triacylglycerols resulted in two series of peaks in the separation of alpine currant (Ribes alpinum) and black currant (R. nigrum) seed oils. The use of the 10-meter column was found to be appropriate for the screening of the triacylglycerol profile in both seed oils studied.     

Analysis of triacylglycerols of seeds and berries of sea buckthorn (Hippophaë rhamnoides) of different origins by mass spectrometry and tandem mass spectrometry

TAG of seeds, berries, and fruit pulp/peel of different subspecies of sea buckthorn (Hippophaë rhamnoides) were analyzed by MS and tandem mass spectrometry (MS/MS). The seeds contained mainly TAG with acyl carbon number (ACN) of 52 with 2–6 double bonds (DB) (20–30%), and TAG of ACN 54 with 3–9 DB (70–80%). In the pulp/peel fraction, the major TAG were species with ACN:DB of 48∶1 to 48∶3 (19–49%), 50∶1 to 50∶4 (31–41%), and 52∶1 to 52∶6 (9–19%). The molecular weight species of whole berries largely resembled those of fruit pulp/peel with additional species of ACN 54 from the seeds (5–24%). Subspecies (spp.) sinensis differed from ssp. mongolica and rhamnoides by having a higher proportion of TAG of ACN 52 (27% vs. 21% and 22%, P<0.05) and a lower proportion of ACN 54 (71% vs. 79% and 78%, P<0.01) in seed TAG. Seed TAG of ssp. mongolica contained a higher proportion of more unsaturated species compared with those of the two other subspecies. Berry TAG of ssp. mongolica had the highest proportion of molecular species of ACN 48 due to the higher proportion of palmitic and palmitoleic acids and the lower seed content of the berries. Overall, palmitic acid favored the sn-1 and sn-3 positions. The order of preference of unsaturated FA for the sn-2 position depended at least partially on the FA combination of TAG. Seed TAG of ssp. mongolica contained a higher proportion of α-linolenic acid in the sn-2 position than those of ssp. sinensis. In berry TAG, ssp. mongolica had the highest proportions of palmitoleic and linoleic acids in the sn-2 position, and the lowest proportion of oleic/cis-vaccenic acid in the sn-2 position, among the three subspecies.     

The regiospecific position of 18∶1 cis and trans monoenoic fatty acids in milk fat triacylglycerols

TAG of butterfat were fractionated according to the type and degree of unsaturation into six fractions by silver-ion HPLC. The fractions containing TAG with either cis-or trans-monoenoic FA were collected and fractionated further by reversed-phase HPLC to obtain fractions containing cis TAG of ACN:DB (acyl carbon number:double bonds) 48∶1, 50∶1, and 52∶1 as well as trans 48∶1, 50∶1, and 52∶1. The FA compositions of these fractions were elucidated by GC. The MW distribution of each fraction was determined by ammonia negative-ion CI-MS. Each of the [M-H]⁻ parent ions was fractionated further by collision-induced dissociation with argon, which gave information on the location of cis-and trans-FA between the primary and secondary positions of TAG. The results suggest that the sn-positions of the monoenoic cis-and trans-FA depend on the two other FA present in the molecule. With 14∶0 FA in the TAG molecule, the 18∶1 FA in the sn-2 position are mostly present as cis-isomers. When there is no 14∶0 in the TAG molecule, the trans-18∶1 isomers seem to be more common in the sn-2 position. Also when other long-chain FA are present, the trans-isomers are more likely to be located in the secondary (sn-2) position.     

The stiffness of laser stake welded T-joints in web-core sandwich structures

The purpose of this paper is to describe experiments carried out on laser stake welded T-joints of web-core steel sandwich structures. A special test setup was developed to measure the shear-induced rotation at the T-joint. The ratio of the shear force to rotation angle gave the joint stiffness. This stiffness was measured for specimens with two different face-plate thicknesses. The influence of weld thickness, root gap and occurrence of contact were further investigated with finite element simulations. Finally, the shear stiffness of the sandwich structure transverse to the web plate direction was determined using the experimentally obtained average joint stiffness value. The validation of the shear stiffness was carried out by considering a beam in four-point bending. The agreement between calculated deflection and stress and experimental results was found to be good.     

A calculation method for determining the limit of flange wrinkling in the deep-drawing of cylindrical steel shells without blankholding

Flange wrinkling in deep drawing of cylindrical cups without a blankholder restricts the depth of the cup. In addition to the blank and tool geometries, the material properties determine the maximum reduction attained. Geckeler, Senior and Kawai have developed theories for calculating the critical hoop stress in the flange and the number of waves formed. In the present work a calculation method for predicting the limiting drawing ratio in drawing without blankholding on the basis of the theories mentioned above and the material properties is developed. By comparing the experimental and calculated values, it is shown that the limiting drawing ratio can be determined theoretically.     

Semi-automated user agents in distributed change management

Flexible integration of distributed design and manufacturing activities is one of the key issues in applying just-in-time principles along the logistics chain. The potential of AI based approaches in this field is clear, but the inherent asynchrony, concurrency, and inconsistency of distributed operations has reduced enthusiasm so far.This paper discusses coordination in the context of geographically distributed manufacturing of one-of-a-kind products. Cooperation of partners is based on semi-automated user agents which operate as an integrative layer between more dedicated tools and systems. The management of order changes in elevator manufacture is used as a case example.The work reported here is part of the DIMUN project (DIMUN, 1989) in the RACE program.     

Applications Are the Drivers in the Mobile Information Society

This short paper clarifies the thoughts of the future Mobile InformationSociety (MIS), ubiquitous access to the information services in wirelessenvironment. The key elements of MIS are explained as well as some of thechallenges MIS sets for the current research and skill development programsin academic and industrial environment.     

Quantitation of acyl migration during lipase-catalyzed acidolysis, and of the regioisomers of structured triacylglycerols formed

Various MLM-type (M, medium-chain fatty acids; L, long-chain fatty acids) structured triacylglycerols were produced in pilot- or small-scale packed-bed reactors by lipasecatalyzed acidolysis. The incorporation and acyl migration of octanoic acid were measured by gas chromatography and Grignard degradation, and ranged from 39.0 to 48.7% and 0.6 to 9.3%, respectively. Quantitation of triacylglycerol molecular species was performed by ammonia negative ion chemical ionization (NICI) mass spectrometry (MS). The proportion of ACN (acyl carbon number) 34 species that contained one C₁₈ fatty acid and two C_8∶0′ in samples analyzed, varied from 12.5 to 23.2%. The selected regioisomers MLM and MML within the ACN 34 species group were quantified by NICI tandem MS (MS/MS) and were in the range of 97.1 to 98.4% and 1.6 to 2.9%, respectively. There was no correlation between the level of acyl migration during lipase-catalyzed esterification and the level of regioisomers of the selected MLM-type triacylglycerols in the structured lipid samples.     

Framework for Sustainable Food Packaging Design

The environmental impacts of packages have been found to be relatively small compared with the food items they contain. Furthermore, from the environmental and operational point of view, the most significant task of the package is to protect the product, which is important to acknowledge in the packaging design process. This study introduces a guiding framework for designing sustainable food packaging. In this approach, the entire life cycle of the product–package combination is taken into consideration. The emphasis is on the prevention of food losses in packaging design as a major environmental criterion. Consideration of the properties of both the package and the product itself when designing the final package will lead to a better end result with smaller product losses and environmental impacts. By using different assessment methods in the different stages of the packaging design, the sustainability of the package can be enhanced. The decision making of the packaging designer is facilitated with methods that are introduced step by step and in a certain order that will also allow for corrective measures through back‐loops in the design process. The purpose is to integrate sustainability aspects at all stages firmly into the design process. Copyright © 2012 John Wiley & Sons, Ltd.