APPLICATION

Application of a shiny glaze on bakery products

The palatability of a backed product is enhanced by a glaze which gives a shine and reflects light. The application must be as even and complete as possible while restricted to the product itself . It should not smear the plate or mesh supporting it. Methods for an accurate dosage and application pattern exist.

Updated Jan 01, 2021 - 10 min Read

BASE

Core products

There is a very wide range of baked product which can be glazed : croissant, bun, bread …

RECIPE

Ingredients

A light glaze can be provided by different ingredients and a combination of them :

  • egg is the traditional glaze medium AKA egg wash
  • milk and milk proteins,
  • soy and vegetable proteins
  • glucose syrup

Heavier glazes are provided by a sugar fondant or a chocolate couverture, in this case the operation refers as enrobing rather than just glazing.

    PROCESS

    How does it work?

    The coating operation consist in applying the glaze on the product while avoiding losses on the immediate surrounding:

    A light glaze is a  dilution of a protein-rich powder or a concentrated slurry into a lighter suspension, the preparation must be kept cold to prevent microbial growth

    For reference, sugar fondant and chocolate couverture are described :

    • Sugar fondant: the preparation involves dispersion of fine sugar in a concentrated sugar solution, the preparation must be kept at constant temperature and agitation to maintain its physical properties – whiteness, viscosity and crunch – resulting from the balance between dissolved and finely crystallized sugar

    • Chocolate: the solid chocolate must undergo a complex operation called tempering: melting, cooling, partial re-melting, the preparation involves a complex system which ensures melting, agitation, circulation and temperature control before use. The operation may be semi-automatic or fully automatic and continuous.

    Losses are recovered or cleaned.

    1.

    Liquid application by brush or spray

    5

    2.

    Stabilisation by baking

    PROCESS

    Coating system

    Different coating systems can be used:

    • Traditional brush
    • Curtain and recovery/recycling of excess in the case of the thick application of a viscous fluid
    • Spraying for accurate application of a low viscosity liquid

     The difference between the systems lies in the engineering details designed to cope with constraints:

    • cooling
    • recycling
    • hygiene and cleanability

     

    PROCESS

    Coating system

    In a high-capacity industrial line, spraying proves the most appropriate application system. If well controlled, it ensures a precise application in quantity and surface.

    PRODUCT EVALUATION

    How do you measure your success?

    Key quality features

    If obviously first visual, the evaluation triggers multiple questions

    Shine

    After completion, the glaze must display a bright shine

    Coverage

    The glaze must be evenly applied and should cover the desired surface, the side of the product being the most difficult

    Stability

    The stability should not be affected by further processing steps : cooling, freezing

    Key quality parameters

    The process displays critical factors to control

    Ingredient composition

    Type of glaze, water content

    Physical characteristics

    Viscosity and surface tension

    Application precision

    Dosage and application precision, resulting also in reduced consumption and improved hygiene