From butteroil

Clearly, the flavor impact of any given compound at any given time depends not only on its chemical nature, but also on its quantitative level, its threshold value and its interaction with the other components present. The purpose of the present work was to study the various parameters which influence the quantitative pattern of volatiles produced from butteroil by heating. 

Table I. Quantitative Analysis of the Polar Components (ug volatiles/g oil) Produced from Butteroil by Heating...

Figure 2. Gas chromatographic analysis of the polar volatile components from butteroil heated for 1 hr at 185 C. Only the relevant peak identifications are given in Table 1.

Micich, T.J, Foglia, T.A., Holsinger, V.H. 1992. Polymer-supported saponins an approach to cholesterol removal from butteroil. J. Agric. Food Chem. 40, 1321-1325. 

Sundfeld, E., Yun, S., Krochta, J.M., Richardson, T. 1993. Separation of cholesterol from butteroil using quillaja saponins. 1. Effect of pH, contact time and adsorbent.. / Food Process Eng. 16, 191-205. 

Yang, B., Harper, W.J., Parkin, K.L., Chen, J. 1994, Screening of commercial lipases for production of mono and diacylglycerols from butteroil by enzyme glycerolysis. Int. Dairy J. 4, 1-13. 

The separation of the positional isomers of acetic and butyric acid-substituted diacylglycerols (palmitoyl and stearoyl) from butteroil was accomplished as their dinitrophenyl isocyanate derivatives on a YMC-Pack 3,5-(/ )-(-l-)-l-(l-naphthyl)-ethylamine column (2 = 226 nm) at 25 C using a 40/10/1 hexane/1,2-dichloro-ethane/ethanol mobile phase [661]. Injections were IO-20ng and elution was complete in <30 min. 

Materials Reagents and authentic compounds for use as standards were purchased in the highest available purity. Butteroil was prepared from unsalted butter by centrifugation at 60 C. Four butteroil fractions of different fatty acid composition, obtained by crystallization at 19 C and 29 C (10), were provided by the Dairy Bureau of Canada. 

In a study on butteroil held at a temperature ranging from —10 to +50°C, oxidation rate increased with increasing temperature but the same flavor was formed on storage and the reaction sequence for flavor formation was similar at all temperatures (Hamm et al., 1968). Dunkley and Franke (1967) reported a decrease in flavor intensity and thiobarbituric acid (TBA) values in liquid milk as storage temperature was increased from 0 to 4 to 8°C. Schwartz and Parks (1974) reported that condensed milk stored at — 17°C was more susceptible to oxidized flavor development than at — 7°C. 

In fractions of butteroil containing alpha-tocopherol and copper. These workers reported that l,5-octadlen-3-one from the oxidation of long-chain polyunsaturated n-3 fatty acids was responsible for metallic notes, but the fishiness appeared to be contributed by the 2,A,7-decatrlenals or a combination of these compounds. This relationship has been explored further In our laboratory through mechanistic studies employing alpha-tocopherol and Trolox C which Is a synthetic tocopherol-type antioxidant (Figure 2). 

Figure 5 Reversed phase HPLC (linear gradient of 10-90% isopropanol in acetonitrile at 25°C) of natural (top) and rearranged (bottom) butterfat triacylglycerols as obtained with light-scattering detector. Peak identification by carbon and double bond number. (Reproduced with permission from Marai L, Kuksis A, and Myher JJ (1994) Reversed-phase liquid chromatography-mass spectrometry of the uncommon triacylglycerol structures generated by randomization of butteroil. Journal of Chromatography A 672 87-99.)...

FIGURE 3.5 Schematic diagram of flat sheet bioreactor apparatus used for butteroil hydrolysis 1, stirrer 2, products 3, membrane reactor 4, water bath 5, temperature controller, 6, oil 7, buffer 8, pump. (From Malcata, F. X., C. G. Hill, and C. H. Amundson, 1991,... 

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