Goodbye scuff marks: Mars heat treats chocolate after tempering to avoid unwanted marks

A short burst of hot air or incubation can prevent unsightly white marks on chocolate obtained via friction during production and packing, according to a patent application from Mars.

The Twix maker has filed a patent under the Patent Cooperation Treat (PCT) for a controlled heat treatment method to remove or reduce unwanted marks by blowing hot air on chocolate after tempering or putting wrapped products in an incubator.

Without undoing tempering

“This result is surprising since the application of heat after manufacture of a confectionery product is generally undesirable as it may lead to de-tempering or heat damage,” said Mars in its application.

Mars researchers found a quick burst of hot air can remove unwelcome marks without undoing the earlier tempering that helps chocolate develop its characteristic glossy texture.

Hot air blast on naked products

Under one method, Mars applies a blast of hot air directly to the surface of the product for a short period of time. For example, it may use a blower at around 65°C for 20-80 milliseconds as the product falls into packaging such as a stand-up pouch.

The blower is placed around 25 cm above the chocolate so the product isn’t singed. Mars says no cooling is needed after the heat treatment.

Mars has tested the method with Twix miniatures in a row of 13 individual bite-size chocolate bars. It took 11 seconds to treat the 13 bars and under a second per bar, it said.

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Naked chocolate products subjected to hot air under blower method. Source: Mars patent

Incubating wrapped chocolates

Mars said an alternative method is to incubate wrapped products in an infra-red heat cabinet or hot climate cabinet with a mild heat (28-29°C) for between 2-24 hours.

“This embodiment is convenient in that the heat treatment may be applied with relatively little user input, other than to load and unload the product from the heat treatment chamber,” said Mars.

Nine-week study

The company has conducted a nine-week ageing study with Twix miniatures under treatment via either hot air, infra-red incubation or a hot climate cabinet.

“All heat treated bars showed significantly reduced scuffing, whereas the condition of the control group was unchanged,” said the patent.

Mars researchers found no adverse effect on the shelf life of any of the bars.

Source:

Pub. No.: WO/2015/167814

International Application No.: PCT/US2015/026177

‘Confectionery Treatment’

Applicant: Mars Incorporated