There’s nothing like the concern of a grandmother to bring attention to food safety.
"Hey Coles - can you PLEASE tell me just what is in your Coles Icecream Sandwiches..." on the Coles Facebook page, July 31 2017.
The incredible stability of her thawed ice cream sandwich led people to ask just what awful chemicals must be in the product to have this effect.
But most of the food additives that are added to ice cream and other edible items to sustain physical shape are derived from natural materials with no known health risks. And other selected additives – for example, some that increase the palatability and stability of food – are also naturally-occuring plant and mineral substances.
Here’s a quick guide to the science behind some of the food additives with a nature-based history you can look for on product labels.
Bringing together oil and water
Emulsifiers are compounds that allow oil and water droplets to interact in suspension: the resulting product is called an emulsion.
Everyday food and beverage emulsions include homogenised milk, mayonnaise and salad dressings. The presence of emulsifiers prevents the fat from separating from the rest of the product: in milk, for example, this means the cream does not rise to the top, but instead stays incorporated in the liquid.
Emulsifiers work similarly to detergents, which might make them sound a little bit off putting, but many of the emulsifiers commonly used in foods are sourced from ingredients already occurring in natural products. Examples include lecithin from or , mucilage from , and components of fatty acids ().
Even manufactured emulsifiers such as DATEM (), and are .
Smooth yogurt and spreadable jam
are to increase viscosity (thickness), smooth the texture, give body and help preserve their structure. Food stabilisers, thickeners, and firming agents are added in a relatively small amount and .
They give a uniform consistency to the product and hold the flavouring . This is used in products like jams, yogurts and jellies to stop the fruit from settling.
They also prevent emulsions from separating. Without stabilisers, your purchased salad dressing and mayonnaise could split – separate into their oil and water-based components – in the fridge. Stabilisers also prevent ice crystals from forming in frozen foods, such as ice cream.
Thickeners and stabilisers are mostly (complex sugars) isolated from plant sources, including starches (e.g. ), vegetable gums (e.g. ), and (e.g. from citrus fruits). Some gums are also obtained from microbial fermentation, where bacteria are fed sugars and produce gums (e.g. ).
Stabilisers from other natural sources include (from algae), (from seaweed) and (from animal collagen). Use of stabilisers and thickeners is , and many have been used in food preparation .
are often mineral salts such as calcium sulphate, calcium chloride and magnesium sulphate. These . Although the names of the mineral salts sound very “chemical”, they are really no weirder than table salt (otherwise known by its chemical name, sodium chloride).
The mineral salts used for firming agents often contain mineral components needed by the body, such as calcium, and the same salts may be used in supplements. Again, these agents have been used throughout history: calcium sulphate, for example, has been used to .
Originating in Sichuan province, combines pork, silken tofu and chilli bean paste
Mapo tofu Source: Alan Benson
Keeping food safe and stable
Acids, bases or neutralising agents are added to foods to regulate acidity: this is important for taste and to prevent the growth of microbes such as bacteria. are sorbic acid, acetic acid and propionic acid.
These may sound frightening (and in concentrated solutions, they might be!) but in small amounts, they are less acidic than our stomach acid and so are nothing to worry about. The human body has its own buffering systems to .
Antioxidants are a common component in foods touted as “superfoods”. Antioxidants are also important preservatives in the food industry, where they help foods last longer by preventing reactions with oxygen.
Ascorbic acid (vitamin C) and tocopherols (vitamin E) are natural antioxidants which can be added to processed foods. They sound much less nutritious when referred to as 300 and 306, which are their additive numbers.
Even synthetic antioxidants such as propyl gallate and butylated hydroxyanisole (BHA) are generally regarded as safe (they are listed on the ). There have been some concerns about adverse results of BHA at high doses in , but at levels ingested by humans, it appears safe.
Additive is not always a dirty word
. They also often contain additives with intimidating chemical names, or referred to just by their standardised additive numbers.
But, the additives themselves are not necessarily the problem. Natural additives can make foods act in unexpected ways, which enhance the consumer experience and often prolong shelf life.
, Postdoctoral Fellow (Human Molecular Nutrition), School of Medicine and Public Health, . This article was originally published on . Read the .
