Vegetative oil

Learning Objectives

• Understand the importance and processing of vegetable oil in manufacturing soaps and detergents.

• Comprehend the production process of soaps and detergents.

• Identify major processes in South Africa that use coal and understand the production processes involved.

• Grasp the cement production process.

Vegetable Oils Overview

Definition

• Vegetable oils (plant oils) are triglycerides extracted from plant seeds or fruits.

• A triglyceride is an ester derived from glycerol and three fatty acids.

Extraction Process

• Involves physical changes or unit operations in the extraction phase.

• Chemical conversions occur during the refining or further processing stages.

Composition of Vegetable Oils

Hydrocarbon Structure

• Vegetable oils consist of hydrocarbons.

• Unsaturated oils: Contain carbon joined by double carbon-carbon bonds, detectable with bromine solution.

• Saturated oils: Comprise single carbon-carbon bonds.

Health Implications

• Unsaturated oils tend to be healthier than saturated oils, impacting health based on their form at room temperature.

Testing for Unsaturation

Bromine Test

• Bromine water is added to the oil; a color change indicates saturation:

  • Colorless = Unsaturated oil

  • Red = Saturated oil

• Higher amounts of bromine indicate greater unsaturation in the oil.

Iodine Value Measurement

Definition

• The iodine value determines the degree of unsaturation in oils, fats, and waxes.

• Unsaturated oils can absorb iodine; saturated oils cannot, resulting in an iodine value of zero.

Classifications by Iodine Value

• Oils categorized based on iodine values (IV):

  • Drying oils (IV > 150): Linseed, tung.

  • Semi-drying oils (IV 100 - 150): Soybean, sunflower.

  • Non-drying oils (IV 70 - 100): Canola, olive.

Types of Vegetable Oils

Examples

• Olive oil, avocado seed oil, coconut oil, sunflower oil, etc.

Global Consumption Trends (2020)

• Notable oils: Soybean oil (28.6%), Palm oil (36.2%), Sunflower oil (12.8%).

Edible vs Non-Edible Oils

Characteristics

• Edible oils: Used for cooking and consumption; contain nutritional elements and require minimal processing.

• Non-edible oils: Used industrially (e.g., in soaps, fuels) and may need chemical processing.

Applications of Vegetable Oils

• Edible oils: Cooking, flavoring.

• Non-edible oils: Industrial applications, including biodiesel production and cosmetics.

Vegetable Oil Production Steps

Major Steps

1. Preparation Process: Planting, harvesting, cleaning of seeds.

2. Pressing Process: Crushing seeds to extract oil, resulting in raw pressed oil and press cake.

3. Extraction Process: Methods include mechanical (pressing) and chemical extraction (using hexane).

4. Refining Process: Cleaning oil involves degumming, neutralization, bleaching, winterization, and deodorization.

Detailing the Pressing Process

• Seeds crushed between rotating screw and stationary ring in an expeller.

Extraction Methods

Mechanical Extraction

• Cold press: Pressed at room temperature, retaining higher nutritional value.

• Hot press: Involves roasting, producing less nutritious oils.

Chemical Extraction

• Involves hexane to remove oil from pressed cakes.

Refining Steps

Key Processes

• Degumming: Removes gums using water/acid.

• Neutralization: Removes fatty acids with alkali solution.

• Bleaching: Removes color pigments.

• Winterization: Removes wax components.

• Deodorization: Uses steam to eliminate odors.

Health Concerns Related to Vegetable Oils

Saturated vs Unsaturated Fats

• Saturated fats can raise cholesterol levels, linked to heart disease.

• Unsaturated fats (especially omega-3) are beneficial, helping to lower cholesterol.

Fatty Acid Classification

• Saturated, unsaturated (monounsaturated, polyunsaturated).

• Importance of omega-6 and omega-3 fatty acids in diet.

Hydrogenation of Vegetable Oils

Process Overview

• Transform liquid unsaturated oils into solid forms by adding hydrogen, increasing their shelf life and melting point (e.g., margarine).

Animal Fats and Waxes

Types of Fats

• Tallow, lard, caul fat, and leaf fat.

Industrial Uses of Oils, Fats, and Waxes

Applications

• Soaps, greases, paints, culinary uses (e.g., coconut oil in soaps and detergents).

Quality Control Parameters

Key Measures

• Free Fatty Acid (FFA) content, Iodine value, Peroxide value, p-Anisidine value, and more.

• Each parameter ensures quality and stability of oils.

Waste Management in Oil Production

Key Concerns

• Managing organic waste and by-products effectively for energy generation or commercial by-products.

Techniques to Minimize Waste

• Improving production/storage control and utilizing residues for animal feed or soil amendments.