Can I Mix Two Different Lots of the Same Soy Wax in One Production Batch or Should I Qualify Them Individually First?
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Why qualify individually first? Because a blend cannot tell you which lot caused a problem. If one lot is off, blending dilutes the symptom but puts it into every candle, and you lose the evidence for a supplier conversation.
Does blending reduce variation? It can reduce the swing between production runs when you blend two passing lots at a fixed ratio over a season. It does not fix a lot that fails on its own.
What must I record for a blend? Both lot codes, the ratio by weight, the date, the batch sheet it went into, and a small retained sample of the blend itself.
Two very different reasons to blend
Makers blend wax lots for two reasons that look identical from the outside and are opposite in intent. The first is consistency: you hold two lots that have both passed goods-in, and by using them at a fixed ratio across a season you narrow the small swings you would see if you ran one lot and then switched abruptly to the next. The second is concealment: one lot is slightly off, or has never been tested, and blending it into good stock makes the difference hard to notice.
The first is a legitimate production decision. The second is a quality decision that has been skipped. The test that separates them is simple: would you have released the lot on its own? If yes, blending is a consistency tool. If no, or if you do not know, blending is a way of not finding out.
This is why the goods-in order matters. Qualification comes first, lot by lot. Blending, if you choose it, comes after both lots have an approved status on their labels.
Qualify each lot on its own first
Before either lot enters the melter together, each needs its own goods-in record. For a lot that has been in production for months, that record already exists. For the new lot, run at least a screen against retained old-lot wax: appearance in daylight, odour of a melted sample, melt and set observation, and a finished-surface check on a small puck. If anything differs, the new lot goes to a paired candle test before any blending decision.
Worked example: 6 kg meets 9 kg
A maker has 6 kg left of CSI 468 lot 1, which has run cleanly for two months, and 9 kg of lot 2 from a new delivery. She pours 200 g candles at 8% load, so each candle takes 184 g of wax. Lot 1 alone makes 6,000 ÷ 184 = 32 candles. Lot 2 alone makes 9,000 ÷ 184 = 48 candles. Blended, 15 kg makes 15,000 ÷ 184 = 81 candles (each figure rounded down).
Now imagine lot 2 has a problem that only shows up after a few weeks on the shelf, such as heavier frosting. If she had kept the lots separate, the problem is confined to 48 candles, and the 32 lot-1 candles are clean evidence of what normal looks like. If she blended before qualifying lot 2, all 81 candles are implicated, the frosting may be milder and harder to attribute, and she has no unblended lot-2 candle to show the supplier.
| Question | Keep separate | Blend at fixed 40:60 ratio |
|---|---|---|
| Candles affected if lot 2 is faulty | 48 | 81 (all of them) |
| Evidence available for supplier | Clear: lot-2 candles vs lot-1 candles | Weak: only a mixture and references |
| Run-to-run consistency if both pass | Step change when lot 1 runs out | Smoother across the 81 candles |
| Batch sheet entries | One lot code per run | Two lot codes and the ratio |
| Retained samples needed | One per lot | One per lot plus one of the blend |
| Wax value at the 5 kg price | ₹3,185.00 ÷ 5,000 g = ₹0.637 per g for both lots | Same cost; blending saves nothing in money |
The table shows the trade honestly. Blending buys a smoother run if both lots are good. It costs traceability and multiplies exposure if one is not. So qualify lot 2 first. If it passes, a 40:60 blend is a reasonable way to finish lot 1 without a visible step change. If it fails, lot 2 stays in quarantine and lot 1 carries on alone.
When blending genuinely helps
There are situations where a planned blend is the better choice. A maker who sells one hero candle all year and buys wax monthly can see small step changes in top finish or throw each time a lot runs out. Blending the tail of each lot into the start of the next at a fixed ratio turns a step into a slope, which customers are less likely to notice. Another case is a lot that passed comfortably but sits at the edge of your normal range, for example a touch firmer, where a planned blend with a lot at the other edge brings production back to the middle.
In both cases the lots have passed, the ratio is written down, and the reason is recorded. That is what makes it a production decision rather than a cover. It is also worth noting what blending does not do: it does not change the wick your formula needs if both lots are within range, and it does not rescue a lot that fails on odour, colour or contamination, because those defects carry straight through into the mixture.
What a blend costs in traceability
A blend is a new material in your records. It needs a name, such as 468 blend L1:L2 40:60, written on the melter log and on every batch sheet it feeds. Keep a small retained sample of the blend alongside the retained samples of each lot; the quantities you keep are a suggested starting point, and a few hundred grams of each usually covers a later comparison.
If a customer complaint arrives, that record lets you test three things side by side: lot 1 reference, lot 2 reference and the blend. If the blend behaves like lot 1, the lot is probably not the cause. If it leans towards lot 2's behaviour, you have a lead to take to the supplier. Without the separate references, you have only the blend and a guess.
A blending rule you can write down
The following rules are suggested starting points to validate in your own workshop, not a standard. Adapt them, then keep them the same from season to season so that your records mean something.
| Condition | Why |
|---|---|
| Both lots released on their own | A blend must never be the first test of a lot |
| Same product and grade on both invoices | Blending different grades is a formulation change, not a lot blend |
| Ratio fixed by weight and recorded before melting | Makes the blend repeatable and traceable |
| Full melt and stir before fragrance | Avoids pockets of one lot in the jar |
| One confirmation candle from the blend | Checks the combination, not only the parts |
| Retained sample of each lot and the blend | Allows a complaint to be traced later |
Where this page fits
CSI already has guides that cover parts of this question. This page covers the goods-in check for the question above; these go deeper on the rest:
Three things to buy for this job
| Option | Price | Status on the September 2026 pull |
|---|---|---|
| 500 g | ₹325.00 | In stock |
| 1 kg | ₹650.00 | In stock |
| 5 kg | ₹3,185.00 | In stock |
| 10 kg | ₹6,370.00 | In stock |
| Option | Price | Status on the September 2026 pull |
|---|---|---|
| 10 kg capacity | ₹21,240.00 | In stock |
| 20 kg capacity | ₹25,960.00 | In stock |
| Option | Price | Status on the September 2026 pull |
|---|---|---|
| Digital scale | ₹354.00 | In stock |
CANDLEMAKINGSUPPLIESINDIA supplies raw materials and production equipment, not finished candles. This guide separates general quality-control practice from what CSI's own product pages state, says plainly what CSI does not publish (lot numbers, certificates of analysis, tolerances), and labels every sample size, tolerance or retained quantity as a starting point for your own validation.
Prices are live CSI prices from September 2026; product pages are authoritative. Where a spec is not published — such as a lot number, a jar's internal diameter or a wick's burn rate — this guide says so rather than filling the gap.
For bulk quotes, questions about a specific delivery, GST invoicing, IFRA and MSDS documents, message us on WhatsApp at +91 7397976926.
Frequently asked questions
- I Have Two Different Wax Batch Numbers in Inventory — Can I Combine Them in One Production Batch or Should I Keep Them Separate for Traceability?
- I Have 10 Kg Left From My Old Wax Batch and 25 Kg From a New One — How Should I Transition Without Creating Unexplained Changes in Finished Candles?
- My Supplier Changed the Packaging of My Usual Soy Wax — What Information Should I Verify Before Assuming the Material Inside Is Unchanged?
- My Wax Supplier Says the Formulation Has Not Changed but My Production Results Have — What Objective Tests Can I Run Before Changing My Candle Formula?
- I’m Buying Soy Wax in 25 Kg Quantities for Commercial Candle Production — What Incoming Checks Should I Perform Every Time a New Batch Arrives?
- How Do I Create an Incoming QC Specification for Candle Wax Covering Appearance, Odour, Melting Behaviour, Hardness, Finished Appearance, Fragrance Compatibility and Burn Performance?
- I Bought 25 Kg of Soy Wax and This Batch Looks More Yellow Than the Previous One — Should I Test It Before Making 500 Candles?
- My New Soy Wax Batch Has a Slightly Different Smell From the Last Batch — Is That Normal or Should I Stop Production Until I Test It?
- My New Soy Wax Feels Softer Than the Previous Bag From the Same Supplier — How Do I Check Whether Its Candle Performance Has Changed?
- How to Maintain Consistency Between Large Soy Wax Candle Batches
- I Need the Same Soy Wax Every Month for Commercial Candle Production — What Should I Check Before Choosing a Long-Term Supplier?
Customer reviews: The reviews at the top are genuine, published Judge.me reviews — Radhaa S (5★, verified); Jaya Sawlani (5★, verified); Subhankar Roy (4★, verified); Sakshi Jain (5★, verified); S.A. (4★, not recorded as verified); PREETHI PRASATH (5★, verified). Names, ratings, dates and products as recorded by Judge.me.
Product facts (September 2026, CSI live store): Premium Coconut Soy Wax CSI 468 (flakes): 500 g ₹325.00, 1 kg ₹650.00, 5 kg ₹3,185.00, 10 kg ₹6,370.00 — coconut-soy blend · stated melt point 50–53°C, pour 58–60°C · stated fragrance load up to 13% · stated shelf life 60 months. Electric Wax Melter (Imported): 10 kg capacity ₹21,240.00, 20 kg capacity ₹25,960.00 — stated 9.5 litres per melt · display 60–100°C with a stated ±10°C deviation · stated 10 kg of soy in about 30 minutes at 100°C. Candle Making Weighing Scale: Digital scale ₹354.00 — digital, grams or ounces · capacity and resolution not published.
Assumptions: Fragrance load is a percentage of total candle weight (200 g = 184 g wax + 16 g oil at 8%). CSI product pages do not publish lot numbers, certificates of analysis, tolerances, jar internal diameters, wick dimensions or mould hardness; where this guide needs them, it tells you to measure or ask. Sample sizes, tolerances, retained quantities, test lengths and acceptance rules are suggested starting points to validate, not standards or CSI policy. Hypothetical supplier prices are CSI prices adjusted by the stated percentage and labelled as such. Worked examples are illustrations. Prices and availability change — product pages are authoritative.