Food Industry Case Study: Refining Edible Oils


Published on

Find the solution for one of the toughest mixing applications in the food industry, refining edible oils. Read this case study on the Process, the Problem and the Solution.

1 Comment
1 Like
  • Hello, Nice post thanks for sharing post. Thanks Muez-Hest
    Are you sure you want to  Yes  No
    Your message goes here
No Downloads
Total Views
On Slideshare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Food Industry Case Study: Refining Edible Oils

  1. 1. Refining of Edible Oils The Advantages Introduction The Process The Problem The Solution HIGH SHEAR MIXERS/EMULSIFIERS FOOD Solutions for Your TOUGHEST MIXING Applications in APPLICATION REPORT
  2. 2. The basic principle of these processes can be summarized as follows: Edible oils obtained from coconut, corn, cottonseed, olive, palm, peanut, soybean and sunflower etc. contain gums and other impurities which are removed by degumming, neutralizing and bleaching processes. FOOD The Process Refining of Edible Oils Degumming Neutralizing Bleaching untreated oil heat In-Line Mixer acid acid reacts with phosphatides (gums) in the oil, making them hydratable oil may pass straight to neutralizing or bleaching without removal of gums (“acid conditioning”) water may be added to hydrate the phosphatides before removal in the separator water separator gums degummed oil untreated, degummed or acid conditioned oil In-Line Mixer sodium hydroxide solution (caustic soda) sodium hydroxide neutralizes excess acid and saponifies fatty acids in the oil a washing stage may be carried out to remove residual soap water separator neutralized oil soap stock spent water degummed and/or neutralized oil water removal oil/clay suspension formed impurities are adsorbed by the clay bleached oil to storage/packing bleaching clay filter clay and adsorbed impurities separator The wide range of oils processed by these methods leads to considerable variations in process requirements: • Oils which tend to emulsify may be held in a vessel after mixing with the reagent to allow the emulsion to break before passing to the separator. • In the degumming process the typical acid addition is 0.1 - 1%. Phosphoric acid is most commonly used, although citric acid is suitable for some oils. • Process temperature is typically in the range of 120 - 160˚F (50-70˚C). • Neutralization process temperature may be higher, up to 200˚F (95˚C) • The strength of the sodium hydroxide solution varies according to the acid content and oil type. • During bleaching, a filter aid such as diatomaceous earth may be added to prevent the finer clay particles from blinding the filter medium
  3. 3. Edible oil refining is normally a high volume, continuous operation. The reagent additions are traditionally carried out using low shear static mixers or inline agitators, which can lead to several potential problems: • The acid and sodium hydroxide solutions make up only a small fraction of the total product, and must be reduced to the smallest possible droplet size to ensure intimate contact with the oil. Low shear devices with a relatively short dwell time cannot easily achieve this. • With the clay addition, conventional agitation cannot rapidly produce an agglomerate- free, homogeneous suspension. • Poor dispersion of reagents reduces process efficiency, leading to increased chemical consumption and waste. The Problem FOOD A Silverson High Shear Mixer can be used for the acid, sodium hydroxide, and clay additions. Easily fitted in place of the static mixer or inline agitator, the Silverson mixer can produce a fine dispersion of reagents in a single pass.This is achieved as follows: The Solution Further reduction in particle size follows as the mixture is forced out through the stator, increasing the surface area of reagent exposed to the oil.This accelerates the reaction, and maximizes the yield. Centrifugal force drives the materials to the periphery of the workhead where they are reduced to a fine droplet/ particle size in the gap between the rotor blades and the inner wall of the stator. The reagent is introduced to the oil just prior to the intake of the Silverson mixer. The ingredients are drawn into the rotor/stator workhead and vigorously mixed
  4. 4. Silverson Machines,Inc. 355 Chestnut Street, East Longmeadow, MA 01028 Ph: (413) 525-4825 • Fax:(413) 525-5804 • Information contained in this report is believed to be correct and is included as a guide only. No warranty is expressed or implied as to fitness for use or freedom from patents. Silverson Machines reserve the right to change product specification without notice. Issue No. 19FA2 • Improved dispersion of reagents into the oil maximizes the surface area exposed to the oil, accelerating the reaction • Reduced chemical consumption and less environmental impact • Rapid processing times • Easily interchangeable workheads and screens allow the Silverson mixer to be adapted to optimize performance for processing a range of oils Silverson offers a range of machines suitable for the acid and sodium hydroxide additions, and the Silverson Flashblend for the clay dispersion: The Advantages High Shear In-Line Mixers • Aeration free • Easily retro-fitted to existing plant • Ideal for continuous processes • Ultra Hygienic models available • Multistage units available offering a greater degree of shear, resulting in finer particle size and faster processing times. Silverson Flashblend • Designed for high speed dispersion of powders into liquids • Minimized cleaning requirements • Minimum operator input required • Easily automated Centrifugal Pump Powder Feed Hopper Venturi Assembly In-Line Mixer Liquid in Product out reagent/oil blend passes to next processing stage Reagent/water fed into line just prior to intake of In-Line mixer. untreated oil in Clay feed hopper