Apr 26, 2010

Newspaper article about "How fast should ice cream melt?"


Someone left a pretty interesting and funny comment asking me which are the local ice cream parlours in Singapore that make use of stabilisers in making their ice cream. (The comment was made in the form of a question in response to a April 25 Sunday Times Lifestyle article titled, "How fast should ice cream melt?" Article can be found at the end of this post.)

It seems that this person knows a thing or two about the ice cream making process. Or has some background in food science. Or has gone for a gourmet class.

But anyways, here is a straight answer to the question: Honestly, I can't name them because I don't know FOR SURE which local ice cream parlours make use of stabiliers (or how much of it they use or what type of stabilisers are used) as I have never really gone round asking the various ice cream parlours myself. (Even if I did ask, they'll probably say it's proprietary information (i.e. trade secret) and won't reveal - which is actually a hint that stabilisers have been added.)

However, the comment contains the main gist of what should have been reported in the article: The fact is that stabilisers, out of all the other explanations (e.g. amount of air, type of emulsifier, size of ice crystals etc.) to explain the melting rate of ice cream, is the most crucial factor to consider.

Stabilisers is what gives ice cream its shape. It is basically what holds ice cream together. It is what allows ice cream to be transported for thousands of miles without melting and refreezing back into icy chunks. And all this is because it prevents ice cream from melting in the first place!

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The Sunday Times, Lifestyle, April 25, 2010
How fast should ice cream melt?
Rebecca Lynne Tan


In Singapore's hot, tropical climate, a lick of cold ice cream is always a welcomed treat.

One usually eats it quickly, leaving little time to melt.

But what happens when you eat it slowly or leave it to sit at room temperature?

You would imagine that it would soon melt and turn into a creamy, viscous mess.

That is what Ms Lisa Seah, an IT professional, thought would happen as well.

But when she met her husband and 11-year-old son at Ya Kun Kaya Toast after doing some shopping, she was surprised to see that the slice of ice cream toast, which had been bought an hour earlier, was still very much intact.

Her son had consumed only one of the two slices, leaving the other piece on the plate.

She says: "It had not melted and it immediately occurred to me that there could be something wrong with this product. Something just wasn't right, it looked too intact."

Lifestyle did a timed test of the ice cream toast available at Ya Kun, which uses F&N ice cream, and also observed small visible changes to its appearance. Though the ice cream had, in fact, melted, it still held its form an hour after being purchased.

Ya Kun says that to date, it has received feedback from one customer who is concerned about the melting rate of its ice cream.

A spokesman for Ya Kun says: "We explained that our ice cream was from a reputable household brand and that the ice cream contained permitted stabilisers and emulsifiers which are necessary to maintain the structure."

He adds: "Our supplier has also assured us that the stabiliser dosage used in the ice cream complies with the FDA (Food and Drug Administration of the United States of America) regulation and is safe for human consumption."

Ice cream is mainly made of sugar, milk solids, fat, stabilisers and emulsifiers.

Lifestyle timed tested four ice cream brands - F&N ice cream used by Ya Kun, Wall's, Haagen-Dazs and ice cream from gourmet chain, Udders.

By an hour, all had melted into a thick cream, and while F&N's still held its shape, the texture had become a creamy liquid.

The melting rate, ice cream makers and food science academics say, depends on a few factors - the amount of air in the ice cream, the size of water crystals, and whether or not emulsifiers and stabilisers have been added to the mixture.

Says Mr David Yim, 39, co-owner of ice cream chain Udders Ice Cream: "The amount of air is a factor in determining the melting rate."

He says that the more air present in ice cream, the faster it melts.

An ice cream with a higher density will have a slower melting rate. Density is dependent on the amount of ingredients used in a given volume.

Ice crystals also play a critical role, experts say.

Mrs Tay-Chan Su Chin, deputy director the School of Applied Science at Temasek Polytechnic, says that the larger the ice crystals, the faster the melting rate.

She adds that consumers should not be alarmed that ice cream often contains stabilisers and emulsifiers.

She says: "Stabilisers and emulsifiers have gone through stringent tests before being approved for use. Emulsifiers are usually compounds that can be bound to both water and oil phases in the food."

Emulsifiers, in the form of lecithin, can be found naturally in ingredients such as soya beans and egg yolks. Emulsifiers are a necessary binding agent as ice creams have significant amounts of fat and water in its composition.

Mr John Ho, 38, senior academic staff from the School of Applied Science at Republic Polytechnic, says: "The main role of emulsifiers is to decrease the surface tension between fat and water, and to compete with milk proteins to emulsify the fat and delay the melting."

Some gourmet ice makers use natural emulsifiers while others do away with it completely.

Ice cream maker, Mr Chronos Chan, 35, co-owner of ice cream shop Tom's Palette in Beach Road, uses naturally occurring lecithin from eggs and soya beans.

Over at Ice Cream Kingdom in Holland Grove, owner Stella Ng, 28, does away with additives altogether.

She says: "I use corn starch as a binding agent to give the ice cream a smoother texture.

"I do not use preservatives for health reasons. A little will not do much harm, but if I can avoid it, I will."

Read about stabilisers here.

1 comment:

  1. hmm i think you're right. there seems to be a lack of mention of stabilisers in the newspaper article

    so i gather that if ice cream does not really melt, it is because of stabilisers?

    and stabilisers also cause ice cream to be sticky?

    ReplyDelete