Steviol Glycosides in Powder Premixes: Dispersion and Blend Uniformity Testing

First decide: a single ingredient or a blended sweetener

Choose the supply format around who will develop and verify the premix.

Even for a blend, define the target market and ingredient constraints first. Requirements for natural origin, leaf extraction, no enzymatic modification, no erythritol, or permitted sucralose directly affect the viable route.

Should steviol glycosides fully or partially replace sucrose, or be used in a blend?

Before selecting samples, answer the following: 1. Is the project a full or partial sucrose replacement? 2. Will it use steviol glycosides alone, or may it include sucrose, erythritol, monk fruit, sucralose or another sweetener? 3. Are steviol glycosides supplying sweetness only, or does a blend need to adjust sweetness onset, bitterness or aftertaste? 4. Will the finished product be a bulk ingredient, a jarred powder, individual sachets or a spoonable product? 5. What are finished-product serving size, reconstitution liquid and temperature, and target sweetness? 6. Which market will receive the product, and what are its requirements for production route, ingredient list and additive identity? Where sucrose is materially reduced, define which ingredients replace the volume, solids and mouthfeel it supplied. Steviol glycosides can supply sweetness, but equal-sweetness calculations do not automatically replace every function of sucrose.

• View monk fruit extract specifications
• View stevia specifications
• View erythritol specifications

Select the steviol glycoside before defining the mix

The name steviol glycoside powder does not specify one composition, production route or powder form. Confirm total glycoside content, the main glycosides, actual production route, any carrier or other sweeteners, and the physical form of the identified sample.

• Compare total glycoside content and individual composition

State requirements for leaf extraction, a particular origin or process, and the ingredient list before samples are selected. Two materials described as stevia may require different doses, declarations or handling. Keep the specification, production-route statement and sample lot together; do not infer a route from a glycoside abbreviation alone.

Dispersibility, solubility and mixing uniformity are not the same results

Record the dry-powder and reconstitution results separately.

A lump-free cup describes that preparation. It does not establish equal glycoside content in every sachet. Conversely, uniform dry-powder content does not establish rapid dispersion or dissolution in cold water, a protein drink or a high-solids base. Retain both quantitative dry-sample analysis and testing under the actual instructions for use.

Why a uniform cup sample does not prove a uniform full batch

Mixing and segregation can occur in the same process. Our starting checks are differences in particle size, bulk density, shape, surface properties, flowability and moisture, followed by the steps that may change distribution after the mixer stops. A visually even powder is insufficient evidence of uniform ingredient content. For a high-intensity sweetener at a low addition, check: - Fine material left on the mixer, feed inlet or packing equipment; - Local concentrations created by the addition sequence; - Particle-size and density differences between the identified sweetener and carrier; - The response to mixing time, rather than assuming longer always improves uniformity; - Distribution after discharge, vibration, conveying and filling; - Moisture uptake, agglomeration or segregation during storage and handling. Oka et al. (2017) compared binary powders in a batch V-blender and a continuous convective tubular blender. Their abstract reports better homogeneity in the continuous blender for the mixtures and process settings examined, with segregation related to particle size and density. It does not validate a stevia premix, specify its mixing time or make one mixer the right choice for every food. Use the study as a reason to test the material–equipment combination, not as a commercial-process specification.

• Oka et al. (2017): Diminished segregation in continuous powder mixing
• Particle-size and granulation guide for sweetener blends

Should steviol glycosides be added directly or preblended in stages?

For a low-addition ingredient, compare direct addition to the full powder batch with staged preblending into a defined portion of carrier. Either is a trial direction; confirm the sequence for the actual powders, equipment, batch size and product. Keep the current process or known formula as the control. Use the same identified sweetener, carrier and other ingredient lots. Change one main variable at a time, such as addition order or preblend level, and record: - Commercial ingredient masses and units on the same final-batch basis; - Carrier identity, grade, particle-size method and result, bulk density, moisture and proportion; - Mixer type, batch mass, fill level, speed or operating mode, mixing time and shutdown sequence; - Distribution through discharge, transfer and packing, as well as inside the mixer; - Reconstitution with the intended liquid amount, temperature and preparation method, followed by sweetness, finish, clumping, floating material and residue. A mesh number without its sieve standard or a bulk density without its measurement method can obscure a material change. Reassess the affected trials when a carrier grade, powder form or addition sequence changes.

Sampling should cover the entire process of mixing, discharging and packaging

A sample from the surface of one finished bag cannot represent all locations and stages. Agree a sampling plan around the mixer, batch size, discharge method, serving size and analytical method. Useful checkpoints include:

Record sample location, time, mass, lot and packing sequence. A large or pooled sample can average out differences between small portions; an undersized sample may not suit the analytical method. State whether results represent individual units, a composite or repeated measurements of the same preparation. Those are different sampling bases, not interchangeable evidence.

Tasting can identify a problem, but cannot replace content analysis

An obvious sweetness difference is a reason to investigate, but taste also changes with aroma, temperature, acidity, base and the preceding sample. Tasting alone cannot establish consistent steviol-glycoside content. Use a quantitative method suitable for the actual matrix and target glycosides. Define the reported analyte, units and basis: an individual glycoside result is not automatically total glycoside content, and a result per gram is not a result per sachet. Confirm sample preparation and method suitability with the laboratory before interpreting the variation. Report the individual results as well as their mean, range and relative standard deviation where appropriate. The same average can conceal very different individual values. Repeated assay readings of one prepared sample do not replace independent samples from the process. The customer's quality, production and laboratory teams should agree the sampling quantity and acceptance criteria for the intended use; this guide sets no universal RSD limit or sample count. Use sensory testing to answer the separate question of whether each prepared product meets its sweetness, onset, bitterness, astringency and aftertaste target. Uniform content does not establish the preferred taste, and similar taste does not establish uniform content.

When a problem occurs, first identify the stage where it occurs

Change one main variable in the next comparison. Keep sample identities, process records and results together so the next decision follows an observed difference rather than an assumed cause.

Verify again when scaling from laboratory samples to commercial production

After laboratory testing, continue verification under conditions close to the intended commercial equipment and batch size. Fix and document: - Raw-material batches and specifications; - Particle size, bulk density and moisture content of the carrier and other powders; - Addition sequence, equipment, batch size, fill level and mixing conditions; - Discharge, conveying, temporary storage and packing methods; - Pack specification and storage temperature and humidity; - Storage conditions and shelf life stated in the current raw-material specifications; - Sampling plan, analytical method and acceptance criteria; - Reconstitution conditions and results for sweetness, mouthfeel and aftertaste. Raw-material shelf life cannot be used directly as shelf life for the blended finished product. Verify the finished product against the full ingredient set, packaging barrier, production environment and intended storage conditions. One successful run supports only the recorded raw materials, equipment and process conditions. Reassess revalidation after a change in carrier grade, steviol-glycoside sample, pack format, production line or batch size.

Start with the premix and the result you need

Provide: 1. Product application and target market; 2. Main ingredients in the current or planned formulation. If sharing the full formula is impractical, provide the details relevant to sweetness, carrier and reconstitution; 3. Full or partial sucrose replacement, or adjustment of sweetness only; 4. Whether use is limited to steviol glycosides or other sweeteners are acceptable; 5. Dose per serving, preparation method, pack format and production equipment; 6. Required sweetness, sensory profile, aftertaste, dispersion and uniformity. Hengliyuan can consider steviol-glycoside composition, production route, a single ingredient or blend, carrier and actual use method to propose samples. Where one steviol glycoside cannot meet both sweetness and use requirements, we can discuss a blended sweetener and a sucrose-replacement sample plan. Trial the sample in the customer’s own formulation and process, then report sweetness, aftertaste, reconstitution performance and results at different sampling points. The next sample direction can be refined from those results. Final production parameters and uniformity criteria remain for the customer to establish with its own equipment, analytical methods and quality system. You do not need a finished test sheet or full formula for the first contact. Send the application and the problem you want to resolve, then add known packaging, quantity, document and sample requirements. Keep the material named in the later specification, sample and quotation consistent.

• Discuss the premix and sample direction

Common questions