Food Processing and Preservation: Fat, Sugar, Plant product Processing

Food Processing and Preservation: Fat, Sugar, Plant product Processing

1. 11 lipid processing technologies

   • Rendering
     • Removes water content and separates fat content
   • Pressing
     • Mechanically squeeze oil from oilseeds
   • Solvent Extraction
     • Separate oil using nontoxic fat solvent
   • Deodorization
     • Strip away odor-causing low molecular weight compounds using steam heat in vacuum chamber
   • Degumming
     • Separates hydrated phospholipids
   • Neutralization
     • Removes free fatty acids
   • Bleaching
     • Removes coloured substances from oil
   • Hydrogenization
     • Saturate double bonds => solidifies it more and more resistant to oxidative rancidity
   • Winterization
     • Remove crystals formed
   • Plasticizing
     • Softens hard fat by creating homogeneous crystal structure
   • Mono and diglyceride preparation
     • isolate triglycerides to use as emulsifiers

2. Testing fat and oil quality

   • Purpose
     • examine physical and chemical properties
     • Measure deterioration (rancidity)
   • Iodine value: measure degree of unsaturation of oil
   • Peroxide value: measure extent of lipid oxidation using peroxide content present
   • Acid Value: measure extent of lipid hydrolysis using free fatty acid content present
   • Saponification value: Measure the physical firmness by using the average molecular weight of fatty acids
     • Tests if there is potential to produce odor
     • Number of mg of KOH required to convert 1g of fat into soap
   • Smoke point: temperature needed for the break down of lipids to glycerol and free fatty acids

3. Fractionation: produce lower melting point butterfat that offers improved "spreadability"

4. Interesterification: produce fats of lower calories by rearranging fatty acids within glyceride molecule