Maltitol in Tablets and Lozenges: Compaction and Sweetness

Chewable tablets and hard lozenges are two of the most demanding places to use maltitol, because the consumer judges them almost entirely on mouthfeel. A compressed piece must form a strong, low-friability tablet that still dissolves or chews pleasantly, and it must taste sweet without the chalky finish or the sharp cooling hit that some polyols leave behind. Compaction behaviour and sweetness are therefore the two properties worth designing around from the first trial.

Why compaction decides the whole project

Maltitol compresses reasonably well, but the grade, particle size and crystal form change how it flows into the die and how it bonds under pressure. A coarse, free-flowing powder feeds a rotary press evenly and gives stable weight; a fine or moist powder can bridge in the hopper and stick to punch faces. Because the same chemical name covers several physical grades, a supplier’s generic datasheet is not enough to predict press performance. Ask for the particle-size distribution and the crystal form, and confirm them with a small press trial before scaling.

Direct compression versus granulation

Direct compression is the simplest route and is often achievable with a well-chosen maltitol grade, especially in chewables where some softness is acceptable. It avoids heat and moisture, which protects sensitive actives, and it keeps the process short. When the blend is too fine, too hygroscopic or prone to segregation, roller compaction or wet granulation produces denser, more uniform granules and a stronger tablet. Wet granulation, however, introduces water and drying, so the binder and drying temperature must be chosen not to dissolve or over-plasticise the maltitol.

Sweetness and mouthfeel in the finished piece

Maltitol is typically around 0.8 to 0.9 times as sweet as sucrose, so a straight swap leaves a chewable slightly under-sweet. The gap is usually closed with a high-intensity sweetener rather than more bulk; adding bulk sweetener to chase sweetness quickly makes the tablet hard and slow to chew. Maltitol also has a low cooling effect compared with some polyols, which suits lozenges that should feel warm and smooth rather than icy. Flavour release depends on how fast the tablet breaks down, so sweetness, hardness and dissolution need to be tuned together, not in isolation.

Solving the usual compression defects

Setting hardness and disintegration targets

Targets should follow the intended bite. A hard lozenge might be pressed to a high breaking force and dissolve slowly over several minutes, while a chewable tablet is deliberately kept softer so it breaks down quickly in the mouth. Fix a specification for hardness, thickness, friability and disintegration time, then verify it on conditioned samples, because tablets measured straight off the press are warmer and softer than the same tablets after equilibration. Disintegration testing is especially useful for lozenges, where a piece that never breaks down leaves an unpleasant residue.

Formulation details that improve the result

• Lubricant balance: too much magnesium stearate weakens bonding and slows dissolution; too little causes sticking.
• Moisture control: keep the blend dry and the room humidity low, because maltitol picks up water and starts to stick.
• Flavour and acid: dry acids and encapsulated flavours reduce interactions that can darken or soften the tablet.
• Antiadherents: a small amount of a glidant can improve flow without compromising hardness.

Frequently Asked Questions