The Fusion of Fats: Plant Oils for Sausages

10 February 2024
Eben van Tonder

Introduction

I have been interested in using plant-based oils to replace fat in meat applications for some time. Richard Bosman and I have been working on such fat marbling to complement fresh meat. I now turned my attention to plant-based fats for sausage production. Like the marbling product for fresh meat, we are working independently and with collaborators from Europe.

When we consider which fat to use, it is important to recognise that the culinary landscapes of various regions across the globe are significantly shaped by the traditional oils they use, influenced by climate, agriculture, and cultural heritage. From the mustard seed oil in North India, known for its warming properties, to the coconut oil in South India and the widespread use of groundnut oil across the country, each oil carries unique characteristics and benefits. Similarly, in West Africa, palm oil has been a staple for millennia, derived from the palm kernel through a process that speaks to the region’s rich history and expertise in oil extraction.

Traditional Oil Extraction Processes

In considering which oil is most suitable to use as fat in sausage meat production, it’s interesting to consider how it is extracted. Let’s look at the traditional ways that various plant oils are extracted.

Mustard Seed Oil: In North India, mustard seed oil is traditionally extracted through a cold press method. The seeds are crushed without using heat, ensuring that the oil retains its sharp, pungent flavour and warming properties. This method preserves the oil’s natural antioxidants and nutrients, making it a favoured choice in colder climates.

Coconut Oil: In Southern India, coconut oil is extracted from dried coconut meat, known as copra. The copra is either cold-pressed, retaining more nutritional value and a stronger coconut flavour, or refined, bleached, and deodorized (RBD) for a neutral taste.

Groundnut Oil: Across the world, groundnut (peanut) oil is commonly extracted using an expeller press, where the nuts are mechanically crushed to extract the oil. This process can be performed at a higher temperature, which increases oil yield but may reduce nutritional quality.

Palm Oil: The traditional method of extracting palm oil in West Africa involves harvesting the palm fruit, boiling it to soften the flesh, and then manually pressing it to release the oil. The oil is then skimmed off the top of the water. This process may allow some seed particles and dietary fibres to remain, which are usually removed through filtration in more refined production methods.

Sunflower Oil: In South Africa, sunflower oil is predominantly extracted through a process that involves de-hulling the seeds followed by mechanical pressing or solvent extraction. The mechanical pressing method, often used by smaller producers, retains more of the oil’s natural flavours and nutrients but results in a lower yield. Larger operations tend to use solvent extraction, which increases yield but requires further refining to remove the solvent residues. The oil is then refined, bleached, and deodorized to ensure safety and improve taste and stability.

In the USA, sunflower oil production primarily utilizes the solvent extraction method, especially for high oil-content sunflower seeds. The seeds undergo pre-cleaning, de-hulling, and crushing before solvent extraction. The extracted crude oil is then refined, which may include degumming, neutralizing, bleaching, and deodorizing to produce an oil with a light taste and appearance. This method maximizes oil yield and efficiency, catering to the country’s large-scale commercial demand. The USA also focuses on producing high-oleic sunflower oils, which have a higher monounsaturated fat content, making them more stable for cooking and processing.

Comparative Analysis of Fats: Without Taking Cooking into Account

We are evaluating the various oils and their properties for inclusion in meat production. When evaluating these traditional oils for modern culinary applications, especially in processed foods like sausages, it’s crucial to consider their smoking points, nutritional content, and the presence of any harmful substances formed upon breakdown at high temperatures.

If we only look at the nutritional value of the different oils, we will get the wrong picture.

I rank the different fats and oils in terms of health benefits for human consumption. The ranking is based on their composition of saturated, monounsaturated, and polyunsaturated fats, presence of essential fatty acids, antioxidant content, and potential impact on cardiovascular health.

A note on terminology. Lard is a semi-solid white fat derived from the fatty parts of the pig. It’s rendered through a process that involves melting and then cooling the fat to achieve the desired consistency. Tallow refers to the rendered fat of cattle or sheep, typically harder than lard and with a higher melting point. It is commonly used in cooking, candle making, and as a lubricant. We include lard and tallow in the list below.

1. Avocado Oil

Nutritional Value: High in monounsaturated fats and vitamin E.
Advantages: Supports heart health, beneficial for the skin.
Disadvantages: Costlier than many other oils.
Risk Factors: Low, when consumed in moderation.

2. Extra Virgin Olive Oil

Nutritional Value: Rich in monounsaturated fats, antioxidants, and polyphenols.
Advantages: Reduces risk of heart disease, anti-inflammatory properties.
Disadvantages: Not suitable for high-heat cooking.
Risk Factors: Low, particularly beneficial when replacing saturated fats.

3. Canola Oil

Nutritional Value: Good source of monounsaturated fats and omega-3 fatty acids.
Advantages: Can lower cholesterol levels, versatile in cooking.
Disadvantages: Often genetically modified; the refining process may reduce beneficial antioxidants.
Risk Factors: Moderate, concerns about erucic acid content have been addressed in food-grade canola.

4. Sunflower Oil (High-Oleic)

Nutritional Value: High in monounsaturated fats, and vitamin E.
Advantages: Good for heart health, stable at high temperatures.
Disadvantages: Traditional sunflower oil (not high-oleic) is high in omega-6 fatty acids.
Risk Factors: Low to moderate; balance with omega-3 fatty acids is essential.

5. Soybean Oil

Nutritional Value: Contains omega-3 and omega-6 fatty acids, and vitamin E.
Advantages: Versatile cooking oil, supports heart health.
Disadvantages: High in omega-6, which can contribute to inflammation when unbalanced with omega-3.
Risk Factors: Moderate, due to potential GMO sources and omega-6 content.

6. Coconut Oil

Nutritional Value: High in saturated fats, and medium-chain triglycerides (MCTs).
Advantages: MCTs can support metabolism and energy.
Disadvantages: High saturated fat content can raise LDL cholesterol.
Risk Factors: Moderate to high, depending on individual cholesterol response.

7. Lard

Nutritional Value: Source of monounsaturated fats, vitamin D.
Advantages: Enhances flavour, good for baking.
Disadvantages: High in saturated fats.
Risk Factors: Moderate to high; saturated fats can impact heart health.

8. Beef Tallow

Nutritional Value: High in saturated and monounsaturated fats.
Advantages: Stable for high-heat cooking, flavorful.
Disadvantages: High in saturated fats.
Risk Factors: Moderate to high; similar concerns as lard regarding heart health.

9. Butter

Nutritional Value: Contains saturated fats, vitamin A, and butyrate.
Advantages: Flavorful, contains short-chain fatty acids and fat-soluble vitamins.
Disadvantages: High in saturated fat, can raise LDL cholesterol.
Risk Factors: High; should be consumed in moderation due to saturated fat content.

10. Palm Oil

Nutritional Value: High in saturated fats and vitamin E.
Advantages: Oxidatively stable, cost-effective.
Disadvantages: Environmental concerns with deforestation, high in saturated fats.
Risk Factors: High; environmental impact and health concerns due to saturated fat content.

Comparative Analysis of Fats: Taking Cooking into Account

When we cook fat, its properties change and it is senseless to only look at the characteristics of oils and fat in isolation without taking into account what we do to it in preparation of the meal. Two criteria are important in evaluating the oils namely the melting point and the smoking points.

The smoking point of plant-based oils and animal fats is a crucial consideration in culinary applications, including their use as fat in meat-based sausages. The smoking point is the temperature at which an oil or fat begins to smoke and decompose, producing harmful substances and negatively affecting flavour. Understanding the smoking point is essential for maintaining the safety, nutritional value, and taste of the food.

In the list below I evaluated the health implications of oils and fats based on their behaviour at their smoking points and I listed it from healthiest to least healthy, taking into account its composition and the harmful substances created at smoking points. I also list the smoking point ranges, and the forms of cooking likely to achieve these temperatures:

1. Avocado Oil

Health Implications: Very stable at high temperatures, producing minimal harmful substances. High in monounsaturated fats, beneficial for heart health.
Harmful Substances at Smoking Point: Minimal production of harmful substances.
Smoking Point Range: 190-204°C (374-399°F).
Cooking Methods: Suitable for all methods, including frying and baking.

2. Sunflower Oil (High-Oleic)

Health Implications: High-oleic versions are more stable at high temperatures, producing fewer harmful substances. Rich in vitamin E and healthier monounsaturated fats.
Harmful Substances at Smoking Point: Lower likelihood of producing harmful substances like aldehydes.
Smoking Point Range: 160-232°C (320-450°F).
Cooking Methods: Versatile for frying, baking, and roasting.

3. Palm Oil

Health Implications: While stable at high temperatures, concerns over saturated fat content and environmental impact. However, less prone to producing harmful substances when heated.
Harmful Substances at Smoking Point: Fewer harmful substances compared to polyunsaturated fats.
Smoking Point Range: 230-260°C (446-500°F).
Cooking Methods: Suitable for frying and sautéing.

4. Soybean Oil

Health Implications: Generally stable at high temperatures but can produce aldehydes and PAHs. High in polyunsaturated fats, which can be beneficial but should be consumed in moderation.
Harmful Substances at Smoking Point: Aldehydes, PAHs.
Smoking Point Range: 234°C (453°F).
Cooking Methods: Frying, baking, and sautéing.

5. Canola Oil

Health Implications: Low in saturated fat and high in monounsaturated fats. It can produce aldehydes at high temperatures but is generally considered a healthier option for various cooking methods.
Harmful Substances at Smoking Point: Aldehydes.
Smoking Point Range: 204-238°C (400-460°F).
Cooking Methods: All-purpose, especially frying and baking.

6. Extra Virgin Olive Oil

Health Implications: High in antioxidants and monounsaturated fats. While it has a lower smoking point, it’s relatively stable and healthier than many other options when not overheated.
Harmful Substances at Smoking Point: Minimal, but can include aldehydes at high temperatures.
Smoking Point Range: 190-220°C (374-428°F).
Cooking Methods: Best for low to medium heat cooking, like sautéing and baking.

7. Beef Tallow

Health Implications: High in saturated fat, but stable at high temperatures, making it less likely to produce harmful substances. Can be part of a balanced diet in moderation.
Harmful Substances at Smoking Point: Minimal production of harmful substances.
Smoking Point Range: 250-260°C (482-500°F).
Cooking Methods: Frying, roasting.

8. Lard (Pork Fat)

Health Implications: Similar to beef tallow, high in saturated fat but also contains monounsaturated fats. It’s relatively stable during cooking.
Harmful Substances at Smoking Point: Minimal production of harmful substances.
Smoking Point Range: 190-210°C (374-410°F).
Cooking Methods: Baking, frying, sautéing.

9. Duck Fat

Health Implications: High in monounsaturated fats compared to other animal fats. Stable at high temperatures, offering a healthier option for occasional use.
Harmful Substances at Smoking Point: Minimal production of harmful substances.
Smoking Point Range: 190-200°C (374-392°F).
Cooking Methods: Roasting, frying.

10. Coconut Oil

Health Implications: High in saturated fats, which are contentious in health discussions. Stable at high temperatures but can produce harmful substances when overheated.
Harmful Substances at Smoking Point: Can produce harmful substances like aldehydes when overheated.
Smoking Point Range: 177-232°C (350-450°F).
Cooking Methods: Baking, frying, sautéing.

11. Butter

Health Implications: High in saturated fat and can produce harmful substances at its low smoking point. However, it’s a source of fat-soluble vitamins.
Harmful Substances at Smoking Point: Acrolein, free radicals.
Smoking Point Range: 121-149°C (250-300°F).
Cooking Methods: Best for low-heat cooking, like sautéing or as a finishing oil.

12. Chicken Fat (Schmaltz)

Health Implications: Contains a mix of saturated and unsaturated fats. It’s relatively stable but should be used in moderation due to the presence of saturated fats.
Harmful Substances at Smoking Point: Minimal production of harmful substances.
Smoking Point Range: 190-200°C (374-392°F).
Cooking Methods: Suitable for frying and sautéing.

Melting Point

Smoking point is not the only consideration. The product must taste good also. Here melting point is key. The melting point of fats used in sausages influences the texture, mouthfeel, and flavour release. Fats should ideally solidify at room temperature but melt at body temperature for a pleasant eating experience.

Here I list the various melting points beginning with the highest (more solid at room temperature) to the lowest melting point (remains liquid at lower temperatures). These melting points are critical in food science for selecting the appropriate fat or oil for a specific application, affecting the texture, mouthfeel, and stability of food products.

Coconut Oil: 24-26°C (76-78°F)
Palm Oil: 35-50°C (95-122°F)
Beef Tallow: 42-48°C (107-118°F)
Lard (Pork Fat): 30-40°C (86-104°F)
Butter: 32-35°C (90-95°F)
Chicken Fat (Schmaltz): 30-36°C (86-97°F)
Duck Fat: 14-17°C (57-63°F)
Extra Virgin Olive Oil: Begins to solidify around 2-6°C (35-43°F)
Avocado Oil: Liquid at room temperature, solidifies below 0°C (32°F)
Sunflower Oil (High-Oleic): Liquid at room temperature, solidifies around -17 to -19°C (1 to -2°F)
Soybean Oil: Generally liquid at room temperature, starts to solidify around -16 to -18°C (3 to 0°F)
Canola Oil: Liquid at room temperature, begins to solidify around -10 to -19°C (14 to -2°F)

The Case for Palm Oil in Sausage Formulations

Considering the typical frying and BBQ roasting temperatures for sausages, palm oil emerges as a compelling option for several reasons:

High Smoking Point: Refined palm oil can withstand high temperatures without breaking down, making it suitable for frying and roasting.
Nutritional Profile: Palm oil is rich in Vitamin E and beta-carotene, contributing to its nutritional value.
Sustainability and Cost: While there are concerns about the environmental impact of palm oil production, sustainably sourced palm oil can be a cost-effective fat option for large-scale use.

Animal Fats in Comparison

Animal fats, such as lard or tallow, have been traditional staples in sausage making due to their flavour and texture. However, when heated to high temperatures, animal fats can undergo oxidation, leading to the formation of harmful substances like free radicals and trans fats. This aspect, coupled with dietary preferences shifting towards plant-based options, makes vegetable oils like palm oil an attractive alternative for sausage formulations.

Conclusion

As we seek to innovate within the food industry, incorporating plant-based fats like palm oil into sausage formulations presents a sustainable, health-conscious, and flavorful option. It’s a testament to the potential of merging traditional wisdom with modern food science to create products that are not only delicious but also nutritionally beneficial.

References

“The Science of Cooking Oils: Making the Best Choice for Your Health” by Dr. Michael Fenster, Cardiologist and Professional Chef.
“Palm Oil: Production, Processing, Characterization, and Uses” by Oi-Ming Lai, Chin-Ping Tan, and Casimir C. Akoh.
“Fatty Acid Composition of Fats and Oils” by the American Oil Chemists’ Society.