From Raw to Ready: The Rigorous Supplement Testing Behind Our Liquid and Powder manufacturing
- CLS
- Jun 10
- 4 min read
Updated: Jul 15
At CLS Manufacturing, we believe the real value of a nutrition supplement isn’t just in its advertised benefits but in what's proven. That’s why testing and quality assurance are more than just regulatory requirements for us; they're core values. Whether you need a high-performance powder or a fast-absorbing liquid supplement, we follow a standard process of best practices designed to guarantee safety, potency, and consistency.
In an industry often overshadowed by bold claims and regulations, CLS stands out by backing every product with integrity. Here’s an inside look at the rigorous supplement testing behind our liquid and powder manufacturing process.
Why Testing Matters in the Supplement Industry
Supplements don’t require pre-market FDA approval. This means it’s up to manufacturers like CLS Manufacturing to self-regulate, test rigorously, and prove that products meet their label claims. This responsibility is critical, especially for powders and liquids. These formats are often preferred for their fast absorption and ease of dosing, but they are also more vulnerable to contamination, degradation, and variation if not managed carefully.
At CLS, we go far beyond basic compliance with current Good Manufacturing Practices (cGMP). Our testing is woven into the entire product lifecycle, from raw ingredient intake through final bottling and packaging.
Raw Material Testing: The First Line of Defense
Every great supplement product starts with high-quality ingredients. Before any raw material enters our production environment, it undergoes a rigorous intake process that includes:
Identity Testing: Using FTIR (Fourier Transform Infrared Spectroscopy) and other methods, we ensure that the ingredient matches its expected fingerprint.
Purity & Potency: We test for concentration levels to ensure ingredients will meet final label claims without over- or under-dosing.
Heavy Metals & Contaminants: This is especially important for plant-based or mineral inputs. We screen for lead, mercury, cadmium, and arsenic using ICP-MS (Inductively Coupled Plasma Mass Spectrometry).
Microbial Screening: We test for pathogens like Salmonella, E. coli, and yeast/mold to prevent recalls and protect consumers.
We require full Certificates of Analysis (COAs) from suppliers and perform in-house verification—trust, but verify.
In-Process Quality Control: Preventing Problems Early
Once production begins, our team implements in-process quality control (IPQC) checkpoints at key stages:
Blending Checks: Homogeneity is vital in powders and liquids. We conduct blend uniformity tests to ensure every scoop or serving delivers the right dose.
pH and Viscosity Testing: For liquids, pH levels and viscosity must remain within a tight range to maintain product stability and usability.
Sampling & Stability Monitoring: Small samples are collected at intervals and subjected to accelerated stability tests to predict shelf-life.
In-process testing minimizes the chance of rework and product rejection.
Finished Product Testing: The Proof of Performance
Before leaving our facility, the final product must meet every quality benchmark. Our finished product testing includes:
Potency Verification: We validate that the key actives are present at the levels stated on the label, using HPLC (High-Performance Liquid Chromatography) or other industry-standard methods.
Microbiological Safety: Final products are tested again to ensure they’re free of pathogens or spoilage organisms.
Physical Consistency: For powders, this includes color, flowability, and moisture content. For liquids, we check for clarity, viscosity, and phase separation.
Packaging Compatibility: Liquids are especially tested to confirm that packaging materials don’t leach or interact with the formulation.
Only after passing this final phase does the batch get released for labeling and distribution.
GMP-Certified Partners
Whenever external testing is required, we rely on trusted and accredited labs. These labs adhere to the highest standards for lab competence, providing third-party validation that supports regulatory audits and consumer confidence.
We also partner with NSF- and FDA-audited facilities for co-manufacturing, packaging, and fulfillment when needed, ensuring our entire supply chain is GMP-compliant.
Traceability, Documentation, and Transparency
Testing is only part of the equation. Equally important is how we document and manage that data. Each ingredient and batch is traceable through:
Unique Lot Numbers
Digital Batch Records
Supplier Qualification Logs
Retention Samples & COA Archives
We maintain a full audit trail for every product. This makes it easy to respond to regulatory inquiries, customer questions, or future reformulations.
Customized QA for Every Client
At CLS, we understand that one-size-fits-all testing protocols do not work. Each product and client has unique needs based on the intended audience, delivery format, and distribution channels. We collaborate with brands to design testing protocols that align with:
Label claims
Product positioning (e.g., NSF Certified, sports-safe, vegan, gluten-free)
Shelf-life goals
International export requirements
Need stability testing for a custom flavor system? Want gluten-free verification or allergen panels? We can build that into your production roadmap.
Create a Culture of Quality Beyond Testing
What sets CLS Manufacturing apart from other US Supplement Contract Manufacturers isn’t just our equipment or protocols; it's our mindset. Every employee, from procurement to packaging, understands that quality isn’t solely the responsibility of the Quality Assurance department; it's everyone's responsibility. Our Quality Assurance team provides ongoing training and process audits to maintain best-in-class standards.
Conclusion: Rigorous Supplement Testing at CLS Manufacturing
When you partner with CLS Manufacturing, you’re not just buying a formulation or a product. You’re investing in confidence. Our comprehensive testing and quality assurance systems are designed to give your brand the credibility it deserves and your customers the safety they expect.
Whether you're developing a new hydration powder, sleep aid liquid, or sports recovery blend, we’re here to ensure every product that leaves our facility reflects excellence, inside and out.
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