The best chocolate filling for cakes is one made with pure chocolate and very little else. It’s also the most expensive, which is why many manufacturers go for a cost-effective alternative where the recipe has a reduced chocolate content supplemented by sugar, vegetable fat and water. A stabiliser and emulsifier bind it all together to secure good stability and texture.
This way it is possible to obtain a filling that consumers perceive to be just as indulgent and delicious as a premium filling high in chocolate.
There is just one processing snag – the tendency of reduced-cost, high pH fillings to develop a firm gel, making them hard to pump on industrial lines. Apart from chocolate, caramel, vanilla and banana fillings all fall into the high pH category.
The undying popularity of chocolate on international markets means that finding solutions to issues of this kind is rarely far from our thoughts. Following up on our work with bake-stable chocolate fillings for croissants, we have investigated whether a similar alginate-pectin stabiliser blend could be an effective choice in fillings for injection into muffins after baking.
What is interesting about this blend is the synergy. Used individually, both pectin and alginate will form a strong gel. Used in combination, the two hydrocolloids ease the processing of fillings over a wide pH range by improving their pumpability and injectability. Gel strength is restored after pumping and injection.
Our test recipe comprised 15% chocolate, sugar and water with no added fat – plus the alginate-pectin blend.
The low chocolate content makes our recipe around four times less expensive than the premium control made with 80% chocolate. Nevertheless, in our small in-house sensory evaluation, more than 90% perceived the chocolate content as being 40% or above, with 54% guessing a chocolate content of 60% - indicating a high level of indulgent appeal.
In our pilot plant, we then measured filling viscosity at processing temperature. As can be seen from the viscosity control graph and photographs below, it is possible to adjust viscosity by dosing the alginate-pectin blend at various levels with and without the addition of calcium and a calcium buffer. The texture of the final filling ranges from being so firm that it can almost be sliced to sufficiently fluid for injection using a thin needle. Even the relatively firm-looking filling pictured in the centre can be pumped with little effort.
During storage, we also observed good stability with no water separation, eliminating the need for an emulsifier in the filling recipe.
These are encouraging results – evidence that indulgent fillings can be both cost-efficient and easy to work with.
We tested GRINDSTED® FB 860 Stabiliser Blend from DuPont™ Danisco®.
Viscosity control in chocolate fillings
(Blue) recipe 1
(Green) recipe 2
(Dark green) recipe 3
(Red) cooling profile of the filling at 1°C per minute
Recipes 1-3 include varying levels of the alginate-pectin blend, calcium and calcium buffer, illustrating the endless flexibility of viscosity control in high pH fillings. Each test recipe comprised 15% chocolate plus sugar and water.