Softgels capsules are a well-established oral dosage form, widely used in both pharmaceutical and nutraceutical applications due to their ability to encapsulate liquid and semi-solid formulations. Structurally, a softgel consists of a continuous shell surrounding a fill matrix, typically produced via rotary die encapsulation. Historically, the shell has been gelatin-based, providing the elasticity and film-forming properties required for soft capsule integrity.
However, from a formulation science perspective, gelatin presents several well-documented limitations, particularly when working with modern active pharmaceutical ingredients (APIs) and increasingly complex delivery systems. As a result, the production of soft veggie capsules technology, specifically starch-based systems, represents a significant advancement, offering a technically robust gelatin replacement with improved performance across multiple parameters.
Why Veggie Softgels?
From a market and consumer perspective, veggie softgel capsules are a compelling alternative to traditional hard shell formats. Compared to standard vegetarian capsules, softgels are particularly well-suited for paediatric and OTC (over-the-counter) applications due to their smooth texture, ease of swallowing, and improved patient compliance. Importantly, their rapid disintegration time supports quicker release and absorption, helping to deliver faster-acting benefits which is essential for both caregivers and consumers.
In the nutraceutical space, vegan softgels are an increasingly popular format for products such as collagen, supplements, and vitamins, where both efficacy and presentation matter. As the demand for clean label product grows, especially in children’s health, manufacturers are prioritising transparency and simplicity in ingredient selection, favouring plant-based alternatives that align with modern consumer expectations. A key driver behind the shift is the rise of vegetarian alternatives for gelatin. These gelatin alternatives not only support vegetarian and vegan lifestyles but also meet broader dietary and cultural requirements including Halal and Kosher standards. As a result, brands can appeal to a more diverse audience by adopting innovative vegetarian alternatives that don’t compromise on performance.
From a formulation standpoint softgels offer several distinct advantages over conventional dosage forms. These include:
- Effective encapsulation of lipophilic or poorly water-soluble APIs
- Delivery of pre-solubilised actives to enhance bioavailability
- Robust protection of sensitive compounds from oxidation and environmental exposure
- Precise dosing in a hermetically sealed system
- Improve patient compliance through ease of swallowing
However, the overall performance and reliability of a softgel system are dependent on the composition of the shell material. As a result, excipient selection plays a critical role in formulation development. Optimisation of shell materials is therefore essential to fully realise the functional and therapeutic benefits of softgel delivery systems.
Limitations of Gelatin-Based Shell Systems
Cross-Linking
A major technical challenge with gelatin systems is cross-linking, which occurs when a reactive species (e.g. aldehydes, peroxides, or certain APIs) interacts with gelatin’s amino acid residues. From a formulation perspective, cross-linking introduces reduced shell solubility, delayed or incomplete capsule rupture, and slowed or incomplete drug release. This can compromise both in vitro and in vivo performance, and in regulated environments, may necessitate the use of enzymes during dissolution testing – adding complexity and variability.
API & Excipient Compatibility
Gelatin is inherently reactive due to its proteinaceous nature, which can lead to interactivity and incompatibilities with oxidising agents, hygroscopic ingredients, or reactive APIs. These interactions can then result in:
- Shell embrittlement
- Discolouration
- Reduced mechanical integrity
- Stability failures
For formulators this often requires additional compatibility screening and may limit formulation flexibility.
Moisture & Process Sensitivity
Soft gelatin capsules require tightly controlled processing conditions, particularly with respect to temperature, humidity and drying. Because gelatin shells contain relatively high levels of water during encapsulation, drying can be lengthy and resource-intensive, often requiring up to 72 hours to achieve equilibrium moisture levels. This can then impact production efficiency, reduce production flexibility, and increase operational costs.
The Advantages of Starch-Based Veggie Softgels
The emergence of starch-based veggie softgel systems represents a shift toward non-protein polymer chemistry in soft capsule design. Unlike in soft gelatin capsules, these systems rely on modified starch matrices combined with optimised plasticiser systems to achieve the required mechanical and functional properties. As a result, this technology stands out as one of the most stable and technically viable gelatin replacement solutions currently on the market.
Eliminating Cross-Linking
A key advantage of starch-based systems is the absence of reaction amino acid residues. As a result, cross-linking reactions are effectively eliminated, meaning dissolution behaviour remains consistent over time and stability profiles are improves, particularly under stress conditions.
For formulation scientists, this translates into:
- Reduced need for excipient screening to mitigate reactivity
- More predictable performance during stability studies
- Simplified regulatory pathways
Enhanced Compatibility
The chemically inert nature of starch-based polymers significantly improves compatibility across a broader range of APIs and excipients. This is particularly relevant for highly reactive compounds, oxidation-sensitive actives, and lipid-based systems. By removing protein-based reactivity from the equation, starch-based veggie softgel systems minimise the risk of unwanted interactions, supporting improved chemical and physical stability of the dosage form. This then leads to greater formulation flexibility, higher API integrity, and more reliable product performance.
The Perfect Veggie Softgel System
The starch-based veggie softgel system relies on the synergistic interaction between three excipient classes. Modified starches UNI-PURE® GA (nutraceutical applications) AND UNI-PURE® GA P-100 (compendial) provide the structural backbone of the shell, while gellan and carrageenan gums establish the gel network responsible for soft capsule formation and strength. Because starch does not possess the natural elasticity of gelatin, flexibility and elasticity are achieved through the incorporation of a sorbitol-based plasticiser. FARMAL® SS 2515 R modulates the polymer network and prevents brittleness, which provides the flexibility, seal integrity, and mechanical strength required for successful encapsulation.
The final shell properties are governed by the ratio of these components and the critical processing parameters, such as cooking conditions, encapsulation settings, and compatibility with the active formulation. Together, these elements create a stable, high-performance softgel shell system capable of replacing the traditional soft gelatin capsule formats.
Faster Drying & Process Efficiency
One of the most significant formulation advantages of using sorbitol-based plasticisation is its effect on drying kinetics. Compared to gelatin soft capsules, veggie softgels exhibit faster moisture equilibration and reduced residual water variability. In practical terms, drying time can be reduced from 72 hours with gelatin, to approximately 24 hours. This can help to deliver increased manufacturing throughput, reduced energy consumption, and improved process consistency.
Mechanical & Stability Performance
Starch-based veggie softgel systems are engineered to deliver:
- Sufficient elasticity for encapsulation
- Structural integrity during handling and packaging
- Resistance to deformation under varying environmental conditions
Importantly, these systems demonstrate high physical stability over time and reduced risk of shell defects such as cracking or leaking. Compared to other non-gelatin alternatives, which may suffer from brittleness or instability, this technology provides a more reliable formulation platform.
Formulation Development & Technical Support
Adopting a new shell system requires careful optimisation of both the fill formulation and encapsulation parameters. To support this, access to dedicated technical infrastructure is critical, which Ingredion offers to support customer processes from formulation to manufacture.
Ingredion have a full softgel pilot-scale laboratory in India to help customers formulate with their chosen actives and fills along with any other ingredients. This facility enables:
- Early-stage feasibility studies
- Proof-of-concept evaluation
- Shell-fill compatibility studies
- Process optimisation prior to scale-up
Early access to encapsulation trials helps to identify potential challenges before significant development resources are invested. Working alongside our formulation experts allows for collaborative problem solving, helping you to:
- Identify potential compatibility issues
- Tailor shell composition to specific APIs
- Optimise fill formulation
- Troubleshoot processing
- Have support on batch scale-up
By addressing the technical challenges early in development, this partnership approach accelerates development timelines and minimises the risk of late-stage failures.