07-Fats+_+Oils_F_13

convert vegetable oil to margarine by partial

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Unformatted text preview: a catalyst OH FST10 ©GMS/GFR 2013 FST10 ©GMS/GFR 2013 Partial Catalytic Hydrogenation Turning Oils into Fats: Catalytic Hydrogenation ! ! ! ! ! lower mp more solid “Reduce” (hydrogenate) all C=C double bonds ! ! ! Convert Vegetable oil to Margarine by partial catalytic hydrogenation - saturating only SOME of the double bonds. ! But partial hydrogenation also converts remaining cis- unsaturations to trans-double bonds “trans-fat” (since trans is more stable) ! trans-fat labeling now required (FDA, 2003). ! Consumers don’t like it ! Illegal in some cities. Fewer double bonds Too stiff Too saturated...unhealthy So, only reduce (saturate) SOME of the double bonds (in this context “reduce” = “hydrogenate” = “saturate”) FST10 ©GMS/GFR 2013 FST10 ©GMS/GFR 2013 Solution ! Split the oil into two batches ! Reduce ALL double bonds in one batch of oil ! ! No C=C double bonds at all Don’t treat the other batch ! Only cis-double bonds ! Mix the two batches ! Add enzymes to rearrange the FAs FST10 ©GMS/GFR 2013 Even more about double bonds ! ! ! European-led research … Cis double bonds are formed in nature Trans double bonds are formed by synthetic chemistry —> hydrogenation and are “un-natural” On labels look for “partially hydrogenated” oils of some kind Generally no longer a concern...if you look for the “No trans fat” label FST10 ©GMS/GFR 2013 FST10 ©GMS/GFR 2013 Changing perception — avoid cholesterol or trans fats? Previous exam examples FST10 ©GMS/GFR 2013 FST10 ©GMS/GFR 2013 5) Which meat grade below has the greatest amount of marbling? 3) Which term describes the distribution of fat throughout meat tissue? ! ! ! ! ! a) Myoglobin b) Polymorphism c) Cellulite d) Marbling e) Retrogradation ! ! ! ! ! FST10 ©GMS/GFR 2013 a) Select b) Utility c) Standard d) Cutter e) Choice FST10 ©GMS/GFR 2013 6) This many calories are found in one gram of fat: ! ! ! ! ! a) 1 b) 3 c) 4 d) 4.6 e) 9 7) Diluting a food with water will ____ the % calories from fat. ! ! ! ! ! a) Increase b) Decrease c) Not change d) Exponentially increase e) Significantly decrease FST10 ©GMS/GFR 2013 FST10 ©GMS/GFR 2013 9) Which vitamin is not fatsoluble? 8) What causes the formation of “chunky butter?” ! ! ! ! ! a) Retrogradation b) Improper churning c) Making butter from non-fat milk d) Different forms of fat crystals e) Low humidity storage ! ! ! ! ! a) A b) C c) D d) E e) K FST10 ©GMS/GFR 2013 FST10 ©GMS/GFR 2013 10) Saturated fatty acids have _____ double bonds. ! ! ! ! ! a) 0 b) 1 c) 2 d) 3 e) Ω-3 11) Trans double bonds are synthetically formed through a process called ! ! ! ! ! FST10 ©GMS/GFR 2013 a) Saponification b) Partial Hydrogenation c) Hydrolysis d) Retrogradation e) Marbling FST10 ©GMS/GFR 2013 Animal & Plant Fats & Oils Fini … FST10 ©GMS/GFR 2013...
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This note was uploaded on 12/06/2013 for the course FST 10 taught by Professor Jack during the Fall '08 term at UC Davis.

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