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

Thursday, 8 January 2015

Texture Analysis in action: Bloom test for gels

Bloom jar gel test using the TA.XTplus Texture AnalyserGELS (Bloom test):
P/0.5 - AOAC method;
P/0.5R - ISO method

XT/BL - Bloom jar

The measurement of gel strength is of widespread interest in the manufacture of pharmaceutical, medical and cosmetic products, and also in areas of the food industry such as confectionery.

Gel properties such as elasticity and rupture force of, for example, pectin, gelatine, agar etc. are important in the development of such products as coronary stents where hydrogel polymers are selected due to their soft, rubbery nature which gives them a strong, superficial resemblance to living, soft tissue.

Tuesday, 6 January 2015

It’s time to perform Textural Magic! Part Two

Multi textured gel balls - "caviar"Performing textural magic with
the use of texturising agents

Continuing our look at the world of Molecular Gastronomy...

Texture Trick No. 1: Spherification:
creating multi-textured gel balls

The spherification technique (created by el Bulli in 2003) consists of a controlled jellification of a liquid which forms spheres when submerged in a bath.

The sphere of liquid surrounded by a delicate membrane of jelly breaks very easily when placed in the mouth, releasing an explosion of flavour.

The spheres can be made in different sizes and have been given names like ‘caviar’ when they are small; or ‘eggs’, ‘gnocchi’ and ‘ravioli’ when they are larger. They are flexible and need to be carefully manipulated. It is possible to introduce solid elements in the sphere which will remain in suspension in the liquid, giving the possibility of introducing multiple flavours and textures in one preparation.

Just about anything can be given the appearance of balls of caviar with this trick. Sodium alginate is mixed with any liquid which is then dripped into a calcium salt and water solution. Scooped out at the optimum time, they should be jellied on the outside and still liquid in the middle as the calcium solution will set the sodium alginate gel. Fruit juices make a nice choice for spherification as you can add them to desserts for a touch of decoration. Alternatively, balls of consommé, or balsamic vinaigrette balls can be presented for an interesting savoury garnish.