Lesson 6: Natural Preservatives
Natural Preservatives — Protecting Your Formulation
✧ Introduction
You can create the most beautiful formulation…
but without preservation, it is not safe.
The moment you introduce water into a product, you create an environment where bacteria, yeast, and mould can grow.
Natural preservation is not about avoiding preservatives—
it is about choosing them wisely, effectively, and responsibly.
✧ What is a Preservative?
A preservative is an ingredient (or system) that prevents the growth of:
• Bacteria
• Yeast
• Mould
It protects both:
• The product
• The person using it
✧ Why Preservatives Are Needed
✧ Water = Life (and Microbial Growth)
Any product containing:
• Water
• Hydrosols
• Aloe vera
• Botanical infusions
…requires preservation.
Without it: → Microorganisms multiply rapidly
→ The product becomes unsafe
✧ Preservatives help to:
• Prevent contamination
• Extend shelf life
• Maintain product integrity
• Protect skin from infection or irritation
✧ How Preservatives Work
Preservatives work by:
• Disrupting microbial cell walls
• Inhibiting growth and reproduction
• Altering the environment so microbes cannot survive
A good preservative system is:
✔ Broad spectrum (covers bacteria, yeast, mould)
✔ Effective at the product’s pH
✔ Compatible with the formulation
✧ Types of Natural & Naturally- Derived Preservatives
Broad Spectrum Systems (Recommended)
Geogard ECT (Benzyl Alcohol, Salicylic Acid, Glycerin, Sorbic Acid)
• Naturally derived
• ECOCERT/COSMOS accepted
• Broad spectrum protection
• Works best at pH < 6
Geogard 221 (Dehydroacetic Acid & Benzyl Alcohol)
• Widely used in natural formulations
• Effective and reliable
• Mild scent
Fermented Preservatives (Use with Caution)
Leucidal Liquid (Radish Root Ferment)
• Naturally derived through fermentation
• Marketed as a “natural preservative”
⚠ Limitations:
• Not always reliably broad spectrum
• Often requires boosting or combination systems
AMTicide Coconut (Coconut ferment)
• Anti-fungal support
• Often used as part of a system
Organic Acid-Based Systems
Sodium Benzoate + Potassium Sorbate
• Food-grade preservatives
• Effective in acidic pH (<5.5)
✔ Often used together for broader protection
Natural Supporting Ingredients (Not Preservatives Alone)
These support preservation but are not sufficient on their own:
• Essential oils
• Vitamin E (antioxidant—not antimicrobial)
• Plant extracts
⚠ These do not replace a true preservative system
✧ How Preservatives Work in Your Formulation
In your product, preservatives:
• Protect against microbial contamination
• Maintain stability over time
• Ensure safe use during repeated exposure (hands, air, water)
✧ Where they are added:
• Typically in the cool-down phase (<40°C)
• At specific usage rates (as per supplier guidelines)
✧ Why Products Contaminate or Spoil
Understanding failure is essential.
Common causes:
1. No Preservative Used
• Most common beginner mistake
2. Incorrect Usage Rate
• Too little = ineffective protection
3. Wrong pH Range
• Preservative not active at that pH
4. Poor Hygiene During Making
• Contamination introduced during formulation
5. Packaging Issues
• Open jars allow repeated contamination
• Water entering product during use
6. High Botanical Load
• Plant materials can introduce microbes
7. False “Natural” Assumptions
• Believing oils or essential oils preserve products
✧ Signs of Microbial Contamination
⚠ These are warning signs:
• Change in smell
• Visible mould
• Separation or unusual texture
• Gas formation or bubbling
• Colour change
⚠ Important:
Contamination can occur before visible signs appear
✧ How to Formulate Safely
✔ Always preserve water-based products
✔ Choose a broad spectrum system
✔ Test and adjust pH
✔ Follow correct usage rates
✔ Maintain strict hygiene during formulation
✔ Use appropriate packaging (airless pumps preferred)
✧ Shelf Life vs Stability
Shelf Life = how long a product remains safe
Stability = how well it maintains structure, texture, and performance
Both are essential—but safety comes first.
✧ Bunyah Botanicals Philosophy
Natural skincare must still be safe skincare.
At Bunyah Botanicals, preservation is approached with:
• Integrity
• Transparency
• Respect for both nature and science
Because true formulation is not just about what we include—
it is about what we protect.
Time to grab a pen and paper:
✧ Quiz: Natural Preservatives
1. What is the primary role of a preservative?
A. Add fragrance
B. Prevent microbial growth
C. Thicken the product
D. Change colour
2. Which products require preservation?
A. Oil-only products
B. Water-based products
C. Powder products
D. Solid waxes
3. What does “broad spectrum” mean?
A. Works on skin types
B. Covers bacteria, yeast, and mould
C. Works in sunlight
D. Works in all packaging
4. Which is a commonly used natural preservative system?
A. Silicone
B. Geogard ECT
C. Alcohol only
D. Fragrance oil
5. Why is pH important in preservation?
A. It changes colour
B. It affects preservative effectiveness
C. It thickens the product
D. It improves scent
6. Is Vitamin E a preservative?
A. Yes
B. No, it is an antioxidant
C. Only in oils
D. Only in creams
7. What is a common cause of contamination?
A. Too much oil
B. No preservative used
C. Too much fragrance
D. Too much water
✧ Answer Key
• B
• B
• B
• B
• B
• B
• B