How to measure and analyse the texture of food, cosmetics, pharmaceuticals and adhesives.

Tuesday, 16 June 2015

Frozen Confectionery Texture: Chocolate Bars

Blade test on choc ice
Does your ice cream product have
a signature texture?
With the advent of more complex ice cream products incorporating inclusions of various kinds the migration of moisture from the ice cream to crisp, particularly cereal-based, components becomes more of a problem.

Particular examples of this are products incorporating wafers either within the ice cream or around the ice cream. Without protection against moisture migration the wafer very rapidly loses its crispness and becomes soggy. If a barrier coating is used between the wafer and the ice cream, this migration is retarded and the product retains crispness for a much longer time. 

Other examples of inclusion are meringue pieces, praline, nuts and chocolate coated puffed rice.

Caramel hardness in an ice-cream bar (green)
vs. caramel in its equivalent ambient chocolate
bar (red) using a 2mm cylinder probe
There is a new hybrid type of product available which is a combination of the ice cream stick or bar with the confectionery bar - an iced candy bar.  A trough of ice cream is extruded and filled with one of the usual candy bar fillings, which may then be topped if desired before the second (hard) stage of freezing.

As ice cream production became more mechanised and the ability to extrude ice cream into blocks became possible, so ice cream manufacturers realised that coating the ice cream in something resembling chocolate gave a product with enhanced sensory appeal to the consumer.  

In the past few years these 'chocolate flavoured coatings' have been replaced by real chocolate coatings in most of the premium quality ice cream products on the market today.  In many ways this change has resulted from the introduction into the marketplace of ice cream analogues of ambient confectionery products.

For the particular application of chocolate for coatings a unique chocolate formulation needs to be developed.  Whilst having the ideal taste, texture and viscosity for the product, the chocolate needs to form perfectly on the ice cream during dipping and withstand the temperature fluctuations of the production process.

The function of the fat in ice cream coatings, whether they are real chocolate or chocolate flavoured, is to act as the continuous phase in which the non-fat solids - sugar, cocoa powder, milk solids - are dispersed. Because the fats have a high solid fat content at freezer temperatures a hard and sometimes brittle coating with a good 'snap' is produced.  

This brittleness can, in some instances, be a drawback as far as the consumer is concerned, particularly if it results in part of the coating falling onto clothing and furniture. The brittleness of the coating can be reduced by making various changes to the formulation of the ice cream coating. However, let us remind you of an anecdote written in a previous blog post:

“When customers complained that they didn’t like bits of chocolate falling onto the floor or staining their clothes, Unilever set about changing the formulation to make the chocolate coating adhere better to the ice cream. In doing so, the distinctive cracking sound of the chocolate coating was lost and consumers complained again".  

It turned out that this was a signature feature of the product experience and this reaction resulted in the return to the original formulation to put back the distinctive solid cracking sound every time one of their consumers bites into this distinctive ice cream bar.

Following wrapping and during subsequent further packing, storage and transit the chocolate should be of sufficient thickness and strength to resist damage, but still deliver the correct 'in mouth' cracking experience to the consumer.

A test assessing such a property, where a flat knife blade is used to cut through the chocolate coating of an ice cream bar,
is shown at the top of the page.

Why not visit the Confectionery Testing page of our website...

For more information on how to measure texture, please visit the Texture Analysis Properties section on our website.

TA.XTplus texture analyser with bloom jar The
TA.XTplus texture analyser is part of a family of texture analysis instruments and equipment from Stable Micro Systems. An extensive portfolio of specialist attachments is available to measure and analyse the textural properties of a huge range of food products. Our technical experts can also custom design instrument fixtures according to individual specifications.

No-one understands texture analysis like we do!

To discuss your specific test requirements click here...

 Confectionery testing videoDownload a published article covering methods for the testing of confectionery

Browse our range of confectionery solutions

No comments:

Post a Comment