You place an order for a new e-liquid online, a flavor profile that sounds perfect: a creamy vanilla custard with a hint of dark caramel. When the bottle arrives, you fill your tank, take a draw, and are met with a faint whisper of vanilla and a sharp, chemical burn. Where is the custard? Where is the caramel? The culprit is often not the flavor concentrate itself, but the ratio of flavoring to the base liquids—a variable almost entirely controlled by the manufacturer and largely invisible to the consumer browsing a digital storefront.
The Mechanics of Flavor Dilution
To understand why that online order missed the mark, we must first break down what is actually inside the bottle. Every e-liquid is a solution, a mixture of four primary components: propylene glycol (PG), vegetable glycerin (VG), nicotine (optional), and flavor concentrates. The ratio of PG to VG is usually the headline statistic on a product page, but it is the ratio of the total flavor concentrate to the PG/VG base that dictates intensity.
PG as the Carrier
Propylene glycol is a thin, water-like liquid that serves as the primary carrier for flavor molecules. Most commercial flavor concentrates are themselves dissolved in PG. Consequently, a liquid with a high PG content (e.g., 70% PG / 30% VG) automatically has more "room" for flavor concentrate, as less of the bottle's volume is occupied by the thick VG. This is why many "high flavor" or "tobacco-style" e-liquids lean toward higher PG ratios.
VG as the Muffler
Vegetable glycerin is a thick, viscous liquid that produces the dense vapor clouds favored by many vapers. However, VG has a naturally sweet, slightly muted taste, and its high viscosity suppresses the volatility of flavor compounds. A high-VG liquid (e.g., 80% VG / 20% PG) physically limits how much PG-based flavor concentrate can be added without making the liquid too thin to wick properly in sub-ohm coils. The flavor is literally diluted by the thick, neutral mass of the VG.
The Supply Chain Problem: "One Size Fits All" Formulation
Many online e-liquid manufacturers produce a single master batch of a given flavor, then fill bottles for all nicotine strengths from that same batch. This creates a hidden inconsistency. Consider a 100 mL bottle of "Blueberry Lemonade" that contains 15% total flavor concentrate. The manufacturer adds a specific amount of nicotine base to create a 3 mg/mL version and a 12 mg/mL version.
The Nicotine Base Variable
The nicotine base used in modern e-liquids is almost always suspended in either 100% PG or a 50/50 PG/VG mix. When a manufacturer adds a larger volume of nicotine base to achieve a higher strength (e.g., 12 mg/mL), they must remove an equal volume of the PG/VG base to keep the bottle full. If the nicotine base is in PG, the higher nicotine version gets more PG, which can actually increase flavor intensity by thinning the liquid. Conversely, if the nicotine base is in a 50/50 mix, the ratio of flavor to base shifts slightly.
The "Max VG" Paradox
A common request from online buyers is "max VG," often interpreted by the manufacturer as "at least 80% VG." To achieve this, the manufacturer must drastically reduce the PG content. Since flavor concentrates are PG-based, the total flavor percentage must be cut. A "max VG" version of a recipe might use only 8-10% total flavor concentrate, while the standard 70/30 version might use 15-18%. The result is a dramatic reduction in flavor intensity that many consumers do not anticipate.
Practical Example: The Custard Conundrum
I once ordered a "Vanilla Custard Tobacco" from a well-known online vendor. The product page boasted "rich, creamy, bold flavor." I selected the 3 mg/mL nicotine strength and the "High VG" option (70% VG / 30% PG). The liquid was almost flavorless. After some investigation through customer reviews, I discovered that the same recipe was used for a 50/50 blend intended for mouth-to-lung devices. The manufacturer simply added less flavor concentrate to the high-VG batch to maintain viscosity. The "bold flavor" promise applied only to the 50/50 version, not the version I received.
The Consumer's Blind Spot: What You Cannot See
When you order online, the product page rarely, if ever, states the percentage of flavor concentrate used in the recipe. You see the PG/VG ratio and the nicotine strength, but not the flavor load. This information asymmetry means you are making a purchase decision based on incomplete data. A 70/30 liquid from one brand might contain 20% flavor, while a 70/30 liquid from another brand might contain only 10% flavor, yet both are labeled identically.
The Role of Steeping
Dilution ratios also affect how a liquid changes over time, a process called steeping. A liquid with a high flavor load (e.g., 18% concentrate) will often taste harsh or "perfumey" when fresh, but will mellow and meld after a week or two. A liquid with a low flavor load (e.g., 8% concentrate) will taste weak from the start and will not improve significantly with time. If you receive a weak liquid and immediately steep it for a month, you may be wasting your time—the problem is the initial dilution ratio, not the lack of aging.
A Forward-Looking Note on Customization
The future of online e-liquid purchasing may lie in transparency and modularity. Some emerging vendors now offer "flavor boost" options at checkout, allowing you to increase the total concentrate percentage by 25-50% for an additional fee. This is a direct acknowledgment that the one-size-fits-all dilution ratio is inadequate for the diverse hardware and preferences of the modern vaper.
If you are consistently disappointed by the intensity of your online orders, consider taking a different approach: buy unflavored PG and VG separately, along with a small bottle of concentrated flavor from a reputable mixing supplier. By controlling your own dilution ratio, you can achieve a consistent flavor intensity across every bottle, regardless of nicotine strength or VG percentage. The power is not in the brand—it is in the ratio you choose to dial in yourself.