For brands, nothing undermines confidence faster than a cream that separates on the shelf or in a customer’s bathroom. Emulsions are inherently unstable systems, and without the right design and manufacturing controls they will eventually try to return to “oil over here, water over there.” From a manufacturer’s perspective, phase stability is not just a formulation issue; it is a quality, reputation, and cost issue. A broken batch can mean rework, disposal, or even a product recall. The goal in professional production is to design and process emulsions so that separation is extremely unlikely under real-world storage and distribution conditions. What Brands need to know about emulsions Most skincare and body-care products built on emulsions fall into one of two structures: Oil-in-water (O/W): Oil droplets are dispersed in a continuous water phase, giving a lighter, faster-absorbing texture ideal for lotions and daily moisturizers. Water-in-oil (W/O): Water droplets are dispersed inside an oil phase, delivering richer, more occlusive textures suited to barrier creams and intense repair products. In both cases, stability depends on how well the oil droplets are created and held in place: droplet size, viscosity, charge interactions, and the strength of the interfacial film all work together to keep the emulsion intact. When that balance is disturbed, the system starts to move toward visible instability. How instability shows up in finished product Understanding the visual signs of instability helps brand owners/formulators/process technicians/compounders interpret what they see during pilot, scale-up, or shelf-life testing: Creaming: Oil droplets slowly rise and form a richer layer at the top. This is driven by density differences and gravity and is often an early warning sign rather than a complete failure. Sedimentation: Heavier dispersed materials (such as water-insoluble powders, clays, or jojoba beads) drift to the bottom rather than staying uniformly suspended. Coalescence: Small droplets start merging into larger ones as the interfacial film fails; this process is typically irreversible and leads to visible “oiling off.” Breaking: The emulsion fully separates into distinct layers and cannot realistically be recovered without reformulation and reprocessing. For a brand, even mild creaming or sedimentation can trigger consumer complaints, while coalescence and breaking are clear indicators that the product is not production ready. Root causes we manage in manufacturing A competent contract manufacturer, private-label, or white-label partner doesn’t just “pick an emulsifier and hope.” We look at stability as the interaction of formula design, process conditions, and packaging. Key drivers include: Emulsifier and oil phase mismatch Each emulsifier system has preferred oil types, usage levels, HLB range, and pH/ionic tolerances. Using an emulsifier optimized for light esters with heavy butters, waxes, or high-polarity oils can strain stability and sensorial desires. The same is true when ionic emulsifiers are paired with high electrolytes or low-temperature conditions without adjustment. In manufacturing, we evaluate oil profiles, polarities, target textures, pHs, and the presence of salt or charged key ingredients, then match emulsifier systems accordingly and keep them within the supplier’s recommended ranges. Oil phase percentage outside the safe window Every emulsifier can only support a certain amount of dispersed phase before coalescence risk rises sharply. Light facial lotions typically sit in the range many systems handle well (roughly 10–25% oil), while rich creams may push into 25–40% or more and require stronger or multi-component emulsifier systems plus higher viscosity support. When brands request “ultra-rich” textures with high oil loads but also want pumpability and low tack, we flag that as a stability risk and propose modified ratios or support ingredients instead of simply increasing oil. Mixing and shear control Droplet size is one of the main predictors of long-term stability. Large, poorly dispersed droplets collide and merge easily; smaller, uniform droplets resist coalescence. That’s why professional plants use high-shear mixers or homogenizers with defined time, speed, and temperature profiles. During production, we control: Order of addition and rate of phase addition. Homogenizer speed and duration during the critical emulsification window. Transition from high shear to low-shear cooling to avoid air entrainment. This is one reason a lab-stable formula can still fail at scale if process parameters are not correctly translated. Temperature profile and phase handling Many emulsifier systems require both oil and water phases to be heated into a defined range (often around 158°F) and held long enough to fully melt waxes and activate polymers before emulsification. If one phase is cooler, or waxes are not fully melted, the emulsion structure can be weak from the start and prone to graininess or early separation. We validate: Phase temperatures at the point of combination. Holding time to ensure waxes/emulsifiers are fully melted. Controlled, gradual cooling so the internal structure sets uniformly rather than “shocking” the system. Electrolytes, pH, and key ingredients Botanical extracts, mineral-rich ingredients, organic acids, and humectants like sodium PCA and glycerin all change the ionic strength and dissolved solids in the water phase. This can affect emulsion viscosity, droplet interactions, and emulsifier performance, especially for ionic or polymeric systems. Similarly, some emulsifiers only remain fully functional within specific pH windows; drifting too acidic or too alkaline after neutralization or key ingredient addition can destabilize the interfacial film. In a manufacturing environment, we control pH at multiple stages and build in compatible buffer systems where needed. Viscosity and Network Support Emulsifiers on their own are rarely enough for long-term stability. Gums, carbomers, fatty alcohols, waxes, and modern rheology modifiers create a 3D network that slows droplet movement, reducing the frequency of collisions and coalescence. We tailor the thickening system to: Support stability under heat and freeze–thaw stress. Deliver the desired sensory profile (e.g., quick-breaking, cushiony, or rich). Maintain consistent viscosity over shelf life. Packaging, Storage, and Stability Testing Your Brand Should Expect Even a well-formulated and well-processed emulsion can fail if it faces temperature extremes, poor packaging choice, or inadequate transport testing. Repeated heating and cooling cycles, or freeze–thaw exposure, can disrupt the emulsion structure, drive crystallization, or cause partial coalescence. Professional stability programs typically include: Elevated temperature storage (e.g., 37–45 °C/98.6-113°F) to accelerate aging and identify early separation risk. Freeze–thaw cycling (commonly three to six cycles between sub-zero and room/elevated temperatures) to simulate shipping and seasonal stress. Long-term real-time storage at ambient conditions to confirm shelf-life targets. Brand owners should also consider packaging compatibility: certain plastics can absorb fragrance or oils, or allow more oxygen ingress, which can contribute to instability or oxidation over time. How a Good Manufacturer Troubleshoots and Prevents Separation When a pilot or production batch shows early signs of instability, a structured review prevents guesswork and protects timelines: Formula review: Check emulsifier type, level, oil phase percentage, and compatibility with key ingredients, pH, and electrolytes. Process review: Confirm heat profile, hold times, order of addition, and shear conditions versus the validated batch record. Packaging and logistics review: Evaluate packaging material, fill temperature, headspace, and expected shipping/storage conditions. From there, we may adjust the emulsifier system, modify viscosity support, tweak oil phase composition, or refine the process parameters and re-run stability. For brands, the key advantage of partnering with a manufacturer experienced in emulsion behavior is that we build prevention into the project from day one. That includes: Advising when requested textures, claims, or highlighted ingredient loads pose a stability risk. Designing lab prototypes with scale-up and regulatory expectations in mind. Validating the process and packaging under realistic stress conditions before you launch. When that upstream work is done well, emulsions can remain cosmetically stable and commercially viable throughout their intended shelf life, supporting both consumer satisfaction and brand reputation. 

When warmer weather arrives, consumer skincare routines tend to shift. Heavier creams and rich oil-based formulations that felt comfortable in winter can feel too heavy once temperatures and humidity climb. That seasonal shift creates a real opportunity for brands to offer gel-based alternatives which tend to be lightweight, water-forward formulas that leave skin feeling hydrated and refreshed without the weight. If you're considering adding gel-based products to your lineup (or repositioning existing ones for summer), here's a closer look at why these formulations resonate with consumers during the warmer months and how they can work across a range of skin types. A Lightweight Option for Oily Skin Types Gel-based (often referred to as “jelly” or “gelly”) formulations tend to work especially well for consumers with oily or combination skin, and that appeal only grows in the summer. Higher temperatures and humidity can increase sebum production, leaving skin feeling greasy and congested. The common consumer instinct is to skip moisturizer entirely when skin feels oily, but that can compromise the skin barrier and increase transepidermal water loss (TEWL). NourishUs Naturals suggests positioning your brand to offer a lighter-weight alternative rather than encouraging customers to skip hydration altogether.  Gel formulations rely on humectants like glycerin, sodium PCA, and hyaluronic acid rather than heavy oils or occlusives. They absorb quickly and tend to leave skin feeling comfortable rather than coated, which is exactly what oily-skin consumers are looking for when it's warm outside. A Comfortable Choice for Dry Skin Types Consumers with dry skin still need consistent hydration in summer, but heavier creams and ointments can feel uncomfortable in the heat. Gel-based hydrators offer a middle ground: they deliver hydration through water-based humectants without the heaviness that can feel oppressive on warm days.It's worth noting that gel formulations may not provide the same level of occlusion as wax or butter-based products. For brands targeting dry-skin consumers, consider positioning gel moisturizers as a daytime option and recommending richer formulations for nighttime use. That kind of routine-based messaging helps your customers feel guided without overcomplicating their purchase decision. Adding humectant-rich ingredients like hyaluronic acid or glycerin to a gel base can enhance the hydrating feel. Hyaluronic acid is a well-known humectant recognized for its water-binding properties, making it a strong ingredient story for consumer-facing marketing. If you want to have a little more nourishment to your hydrating gels, simply mixing in lightweight responsibly grown oils such as Camellia Seed Oil or Argan Oil (to name a few) is a great way for that add moisture without the heaviness of a cream moisturizer. Supports Daily Hydration The skin's moisture barrier helps retain water, oils, and nutrients in the deeper layers of the epidermis. Enjoying a sunny day outside and warm temperatures can increase TEWL, meaning skin may lose hydration faster than in cooler conditions. Water-forward gel formulations can help replenish that lost moisture, supporting a hydrated, healthy-looking appearance. When humectants are incorporated into a gel base; such as glycerin, hyaluronic acid, or panthenol; they draw moisture from the environment and deeper epidermal layers to help the surface feel more hydrated. Pairing humectants with soothing botanicals like aloe creates a formula that feels refreshing on application while delivering a noticeable hydrating experience. For brands, this combination is an easy-to-communicate value proposition: lightweight hydration that consumers can feel working. Where Aloe Fits In While the aloe vera plant itself is roughly 99% water, most cosmetic formulations use a concentrated aloe extract powder (typically a 200:1 ratio) that is reconstituted during manufacturing. This approach preserves the beneficial mucopolysaccharides, amino acids, and natural polysaccharides that consumers associate with aloe (the soothing, cooling sensation on application) while offering microbial stability and shelf life that finished cosmetic products require. For B2B brands, aloe-based formulations check several boxes: Consumer recognition: Aloe is one of the most universally recognized and trusted cosmetic botanicals. Label appeal: Aloe bases align with the demand for naturally derived, transparent ingredient lists. Formulation versatility: Aloe gel bases are compatible with a wide range of added ingredients, making them ideal for private-label customization from added humectants and botanical extracts to fragrance and texture adjustments. Build Your Summer Line with NourishUs Naturals NourishUs Naturals offers gel-based formulations built around ingredients like responsibly grown aloe, responsibly grown papaya extract, and provitamin B5 (panthenol), making ready-to-customize bases designed for brands that want to bring high-quality, summer-ready products to market without starting formulation from scratch. All these gel bases can also be used as is, with no need to add additional ingredients if your brand doesn’t require it.Whether you're expanding an existing line with seasonal offerings or launching a new collection, our gel bases provide a proven starting point with the flexibility to make the finished product your own. Explore our gel-based formulation options or contact us to discuss customizing these bases for your brand. All product descriptions and suggested uses are provided for cosmetic and informational purposes only. Brand owners are responsible for final claims, labeling, and regulatory compliance in all markets of sale.

Why adjust viscosity? Viscosity (thickness) is one of the main differences between a fluid lotion, a richer cream, and a dense conditioner. It affects how a product pumps, spreads, and feels on skin or hair, so being able to systematically thicken or thin an existing base is useful in both R&D and small production tweaks. If you'd like some guidance on how to fix the viscosity of a body wash or shampoo, check out these instructions. Or for more on natural thickeners, check out this blog. Thickening lotions, creams, and conditioners with Xanthan Gum For finished emulsions that are a bit too thin but otherwise stable, one of the simplest lab‑friendly approaches is to use Xanthan Gum as a rheology modifier. Typical usage considerations: In emulsions, Xanthan Gum is usually used around 0.1–0.5% of the total formula; higher levels can lead to a very gel‑like or stringy texture. When formulating from scratch, xanthan is normally dispersed into the water phase before emulsification. For existing bases, it can be post‑added carefully as described below. Step‑by‑step method for post‑thickening with Xanthan Gum: Weigh and record the amount of Xanthan Gum you plan to use as a starting estimate. Weigh your lotion, cream, or conditioner and record the weight. Begin mixing the product with suitable shear (for example, a stick blender or overhead mixer). While mixing, slowly sprinkle in the Xanthan Gum, allowing it to hydrate and distribute before adding more. Continue until you reach the desired viscosity, then stop mixing. Weigh the remaining Xanthan Gum; subtract this from your starting amount to determine how much you actually added. Calculate the Xanthan Gum percentage relative to the total product weight. This becomes your working usage level for this specific base, and you can incorporate that percentage into your formula if you are reformulating from scratch. After any significant adjustment, check the product for signs of instability (for example, separation, excessive aeration, or undesirable stringiness) over time. Still feeling a little unsure? Follow along with our video tutorial here! Thinning lotions, creams, and conditioners with water or distillates If a lotion, cream, or conditioner is too thick, the usual approach is to add more aqueous phase, such as either preserved deionized water or a suitably preserved distillate/hydrosol, all while maintaining an effective preservation system. Key points before thinning: Adding water or distillate dilutes the original preservative system; the finished formula must still be adequately preserved. We love utilizing our Cucumber Distillate for this purpose. Many cosmetic distillates are supplied with their own preservative, but the overall product still needs to be evaluated as a whole. If you are using deionized water, it should be preserved before addition or added in a way that you can calculate the final preservative level in the complete formula. Phenoxyethanol is commonly used up to a maximum of 1% in finished cosmetic products, often supported by a chelator such as Tetrasodium Glutamate Diacetate (GLDA) at around 0.1–0.5% as a booster. Example approach for pre‑preserving added water: Prepare a preserved water phase using a Phenoxyethanol‑based system plus GLDA, keeping in mind that the final Phenoxyethanol level in the finished product should not exceed 1%, and GLDA is typically used around 0.1–0.5%. Step‑by‑step method for thinning with preserved water or distillate: Weigh and record the amount of preserved deionized water or preserved distillate you expect to need. Weigh your lotion, cream, or conditioner and record the weight. Begin mixing the product with gentle to moderate shear. Slowly add the preserved water or distillate while mixing until the desired viscosity is reached. Weigh what remains of your water or distillate and subtract from the original amount to see how much was actually added. Calculate the percentage of water or distillate relative to the total product weight. Use this percentage as your reference if you need to repeat the adjustment on the same base, and integrate it into your formula if you are reformulating at the development stage. Any time you significantly change the water phase, plan to re‑evaluate the finished product’s microbiological and stability profile, especially if the product is intended for market. Final checks and best practices When you adjust viscosity on an existing base: Document all weights and percentages so that successful adjustments can be reproduced at scale. Recheck pH, viscosity, and appearance over time; thickening and thinning can subtly influence emulsion stability and sensorial properties. For commercial products, confirm that the adjusted formula still meets your internal preservation, stability, and performance standards, and consider challenge testing if the water phase has changed meaningfully. Check out our great stock creams, lotions, and conditioners! The options are limitless when you customize one of our stock products. Plus, we love knowing how you alter and customize our bases to suit your brand! Please don’t hesitate to share your story with us or reach out with any questions.

Propylene Glycol is a widely used cosmetic ingredient valued for its humectant and solvent performance in everything from cleansers to creams. At the same time, many brands are looking for glycol options that better align with naturally derived positioning or “propylene glycol–free” ingredient philosophies.  One common option is Propanediol (often 1,3-propanediol)—often available from bio-based supply chains (for example, corn sugar–derived via fermentation, depending on the supplier and grade)) and used in personal care as a multi-functional support ingredient.    Why brands consider an alternative  Ingredient decisions aren’t only technical—they’re commercial. Both indie and established brands see more end customers researching INCI lists and forming opinions from a mix of scientific and nonscientific sources. As consumer scrutiny increases, some brands choose to avoid certain ingredient names on labels, even when the ingredient is permitted and broadly used.    For sensitive skin positioning specifically, propylene glycol is documented as a potential irritant or sensitizer in a small subset of individuals, even though it is considered safe for use in cosmetics when formulated with correctly. For a brand owner, this often translates into a simple brief: “Can you build this formula without propylene glycol?”—even when the driver is perception rather than a regulatory requirement. Providing propanediol as an option lets you respond to those requests without changing the core product experience or making negative claims about propylene glycol itself.   Propylene Glycol vs. Propanediol: What’s actually different?  Although Propylene Glycol and Propanediol share the same chemical formula (C₃H₈O₂), they differ in molecular structure and therefore have different identifiers and regulatory listings (e.g., distinct INCI names and CAS numbers).  Propylene Glycol  Commonly produced from petrochemical feedstocks (industry standard supply chain) Well‑established use history in cosmetics; however, patch test data and case reports show irritation or allergy in a subset of users. SDS references typically list a closed‑cup flash point a little above 100 °C, depending on grade and method Propanediol (1,3-Propanediol)  Often available as bio-based, renewable or plant-based feedstocks (commonly corn sugar–derived) Frequently used as a humectant/solvent in naturally positioned formulations Some suppliers report favorable sustainability metrics vs. propylene glycol (example: lower fossil-based carbon inputs compared with conventional glycols). Environmental claims should be confirmed against the specific supplier’s documentation you are using   Practical formulation notes when switching  In many formulas, propanediol can be evaluated as a 1:1 replacement for propylene glycol, but performance depends on the overall system (surfactants, polymers, preservatives, electrolyte load, etc.). If you encounter haze or solubility changes:  Add propanediol into the water phase first Consider a modest temperature increase during processing (as appropriate for the formula) Re-check clarity after cool-down and 24–48 hours  Formulation Tip: Typical use range targets 3–5% in emulsions, and a bit higher in toners. Actual optimal level may vary by formula, supplier grade, and desired sensorial profile. Always make sure you test your preservative performance when changing anything in a formula. Challenge or PET/compatibility testing as appropriate.    Have any formulation questions? Feel free to reach out to our team via phone or email!  Don’t have time to formulate? Check out our current formulas with propanediol by typing the ingredient into our search bar.