Sweet, smooth and creamy
THE sweet and creamy ice cream, much craved by children and adults, is basically an iced-up milk product. To titillate the taste buds and visual appeal of ice cream lovers, many formulations are developed using emulsifier, stabiliser, colour and flavour.
Classic ingredients
Besides the cold sensation, we enjoy eating ice cream for its excellent taste and texture, which are contributed by the creamy components in milk such as fat and protein.
Milk fat, also known as butterfat gives the ice cream its body and richness in flavour. The fat has a smooth texture which lubricates the palate. The milk solids, which are mainly proteins, further enrich the taste and improve the water-holding capacity to make a thick body which is less icy in texture.
The original source of these creamy ingredients derives from fresh milk. However, in recent years, owing to general concern about cholesterol and calorific value, alternatives such as palm and other vegetable oils, skimmed milk powder and caseinates (non-dairy creamer) have replaced fresh milk.
Soft or stiff peaks
Most consumers prefer sweet ice cream. However, sweetness is only one of the factors. Many ice cream connoisseurs are delighted to see twisted ice cream on cone served in ice cream bars or fast food chains. This visual delight is certainly appealing to many, especially children who are fascinated by the colourful spiral of the mouth-watering creamy ice cream.
The common white sugar on our table, sucrose, is the main sweetener used in most of the standard formulations. Other sweeteners are also used to manufacture products of different textures.
High fructose corn syrup is used to make the soft ice cream that can be scooped onto wafer cones. Some outlets are equipped with dispensers that shape the ice cream into a spiral snow mountain with one or two long peaks. These wavy soft peaks fascinate many young consumers.
Corn syrup is another sweetener that gives a firmer and chewier body to ice cream.
Not gummy gum
In the early years, ice cream was coarse and had gritty icicles. This type of old-fashioned gritty ice cream has made a comeback recently.
Generally, if we find grits of ice in our ice cream, we feel that something is not right with the product. But smoothness in ice cream does not happen naturally. The texture can be improved with the use of stabilisers or thickeners labelled as vegetable gums.
The vegetable gums are not like the glues or adhesives which we use to stick things together. Vegetables gums are thick and viscous, but they are not usually tacky. Vegetables gums are the polysaccharides or complex carbohydrates found in plant or seaweed.
You will normally find these terms or code numbers on the labels. The two commonly-used vegetables gums are carrageenan (E407) and guar gum (E412). Locust bean gum (E410), xanthan gum (E415), carboxymethyl cellulose (E466) and alginate (E401-4) are the alternatives. The xanthan gum, which is produced by micro-organisms, is more expensive and is used to a lesser extent.
Each of the stabilisers has its own characteristics and often, two or more are used in combination to lend synergistic properties to improve their overall effectiveness.
In traditional formulation, gelatine, which is a protein of animal origin, was commonly used as stabiliser. Nowadays, it has been replaced by the more effective vegetable gums.
Bulk up with air
Have you ever noted how much ice cream is left in the container after it has melted? Do not be surprised to find a full box only half-full with liquid.
Churning is an important process in ice-cream making. It helps to set up the structure and texture in ice cream with air, which is very similar to the structure in whipped cream. The structure may collapse on storage, especially when there are changes in storage temperature. The added stabilisers and emulsifiers function in binding the fat and water as well as the air distribution that are necessary for the characteristic desired in ice cream.
Two emulsifiers that predominate in most ice cream formulations are the mono- or di-glycerides of fatty acids (E471) and polysorbate 80. Lecithin (E322) or esters of mono-glycerides of fatty acids (E472) may also be used as the alternatives.
Safety concern
The additives used in ice cream manufacturing are given the GRAS (generally recognised as safe) status. Scientists at University of Iowa Health Center reported that locust bean, guar and xanthan gums are safer to human health than carrageenan. Carrageenan, which is an extract of Irish moss or other algae, is the most popular additive used in food such as in dairy, confectionery, bakery and seafood products. It is also used in cosmetic and pharmaceutical products.
Vegetables gums may ease bowel movement. Drinking some water after eating ice cream would help to digest the additives, especially if guar gum is used in the product. However, guar gum may cause nausea in some people.
People who are allergic to milk protein or who are lactose intolerant may have to avoid eating ice cream.
The emulsifier lecithin is a product of soya or egg. People who are allergic to soya or egg may have to look out for E322 or lecithin on the label.
Always keep ice cream at a constant freezing temperature. Once warmed and refrozen the ice cream would become icier in texture. A box of ice cream that has been opened and thawed will allow microbial growth, which may cause stomach discomfort to young children.
If you are on weight control, watch out for the calories in ice cream. Depending on formulations, calories in 100g of ice cream could be three to four times the calories in 100g of milk.
Chia Joo Suan is a food chemist who advocates safe eating habits. She is the author of What’s in your food? (Pelanduk).
RSS
