Sunday, May 3, 2015

Starch by Joanna Blythman



Joanna Bythman is an investigative food journalist and influential commentator on the British food chain. This book (Fourth Estate, London, 2015) is an examination of the food processing industry in the U.K., Europe and America; how it works and the character of its products. Here  I present her chapter on starches, followed by her brief remarks on recent advances in nanotechnology as applied to packaging.
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In food manufacturing starch is essential kit, by far the most commonly used item, in the food manufacturer’s box of tricks, as one authority explains: ‘Since their development in the 1940s, modified food starches have become a vital part of the food industry. Practically every category of food utilizes the functional properties of starch to impart some important aspect of the final product.’

It’s no exaggeration to say that the modern processed food industry is predicated on the stuff. This is why, when you turn to the ingredients listings on the massed ranks of manufactured foods, the word starch turns up with regularity, sometimes prefixed by a source, say, potato starch, or more often by the enigmatic word ‘modified.’

Starch acts as a muse for the modern food industry, a biddable, versatile, obliging substance that inspires a never-ending flow of creativity. Although it is utterly lacking in any food personality of its own, the very neutrality of nondescript starch makes everything feasible. Think of it as a facilitator, an ingredient that generates a boundless range of technical possibilities.

Added starch makes puffed potato snacks and breakfast cereals crisp and expansive, it makes your tortilla chip crunchier, and your crisps crispier. It lends smoothness and creaminess to processed cheese. It extends the shelf life of yogurt, gels fruit and cream fillings, adds fiber to bread, replaces eggs, makes batter more clingy, adds porosity to crackers, and airiness to cakes. In tumbled, injected and emulsified meats, such as sausages and ham, it can mimic fat, so acting as a ‘meat extender’. Starch seals in moist glazes and marinades and acts as a carrier for flavorings and colorings. It stops your orange juice from separating and makes it cloudy. Starch binds the water in mayonnaise, margarine, ketchup and salad dressings, toughens up dough for the onslaught of factory baking, and adds viscous heft to bouillons and gravies. It stiffens canned foods – soups, pulses, vegetables – and makes ready meals more resilient to the temperature changes posed by chilling, freezing, transportation, reheating, and the general stress and elevated temperatures of factory production. Starch providers ‘freeze/thaw stability’, prevents freezer ‘burn’ and gives food more ‘microwave tolerance.’ Last but not least, it can create texture. Whatever consistency is needed – crisp, crunchy, smooth, shreddable, jellied, stringy, cuttable, short, smooth, cohesive or chewy – multi-tasking starch can deliver it.

But how can one boring, anodyne ingredient do so much? After all, starch in the form that ordinary people know it, such as cornflower and arrowroot, can only perform a fraction of the tasks mentioned above. As you might have guessed, the starches available to food manufacturers are rather remote relatives of those we might use at home. They have been altered in various ways to endow them with properties they lack in any of their recognized household forms. Natural starches, you see, are badly behaved, dysfunctional starches that can only ever find their true potential through the improving hand of food technology.

Modified starch, the most familiar of these ‘improved’, more ‘functional’ starches, has clocked up decades of steadfast services to industrial food manufacture. This type of starch can be made using various techniques to change its characteristics. These include breaking it down with acids, bleaching it, converting it with enzymes, pre-gelatinizing it by heating and drying it so that it forms a gel in cold water, oxidizing it, cross-linking it with fats, converting it into esters or ethers, and bonding it with phosphates. Starch can also be browned using dry heat (dextrinization) to turn it into ‘starch sugars’, such as maltodextrin. Put it this way, modified starch is definitely not something you could cook up in any home kitchen.

There are many types of modified starch, each with unique properties and functions, a case of horses for courses. The starch in canned soups, for example, is often bonded with phosphates, which allows it to absorb more water yet stop any separation in the liquid. To prevent tomato sauce spilling of the factory pizza during baking, a modified starch treated with chorine solution is often added to the topping.

In Europe, modified starches are considered as food additives, and must carry an E number. These days, because the prefix ‘modified’ tend to ring the wrong bell with consumers, starch companies are developing a new tier of more functional ‘clean label’ starches that can lose the label-polluting M - word and E number, and be replaced with the more consumer-friendly ‘soluble fiber’, ‘starch’ or ‘dextrin’ tags.

These new wave starches are presented as more natural because the have not been chemically altered. Instead, only physical and mechanical techniques such as heat, extrusion, drum drying, compression and atomization can be used to change the particle size and structure. Because these newer functional starches are branded and trademarked, the companies that produce them need only volunteer minimal information about how they are made because the method becomes their intellectual property (trade secret).Marketed as specialty starches targeted for specific uses, they have really caught on with manufacturers. As one academic explains, ‘specialty starches continue to outpace unmodified starches in the processed food industry because of their ruggedness and ability to withstand severe process conditions.’

It’s easy to see why food manufacturers take such a keen interest  in starch, both old-timer and new guard. Whether it comes from corn, wheat, cassava, peas or potato, starch is wonderfully cheap and abundant because it is made from commodity cereals and cash crops that are much less expensive than other categories of foods. Therein lies the appeal of starch. It provides reliable, inexpensive bulk to pad out pricier ingredients, which makes for cost-effective replacement, as this starch company tells food manufacturers:

Like you, we are committed to keeping costs low. Our business is built on successfully replacing expensive ingredients with more cost-effective alternatives, helping you to withstand price fluctuations. Whether replacing expensive texture systems or substituting costly proteins, our starches will meet all your expectations and reduce ingredient costs. So what’s the secret of creating foods that appeal to customers’ concerns about cost and quality? Take a fresh look at your recipes and replace expensive ingredients withy no-compromise alternatives to reduce cost, not consumer appeal. We can provide you with tools to replicate the eating enjoyment and texture consumers look for at a fraction of the cost.

With the aid of starch, manufacturers can use ‘cost optimization’ to ‘value engineer’ their product for the benefit of price-sensitive shoppers. A worthwhile mission, surely?

Yet when you read the sales literature for starch products, a strong sense of self-interest on the part of food manufacturers emerges. Here, for instance, is how one starch company sells its starch-based fat replacer:

[It] cleverly allows food manufacturers to remove some butter content from products and still use the label ‘all butter’, which highlights to consumers that the food is still a decadent product. The finish of the product would retain the same ‘shortness’ and buttery richness and mouth-feel as the full fat equivalent.

Hey, presto. The addition of starch allows opulently labelled ‘all butter’ biscuits or croissants to contain less butter than they did before. Not quite what your average person might deduce from the label. The fat-replacing starch being recommended here goes by the name of Delyte, presumably a play on delight/delicious and lite/light (low fat). Or possibly the person who thought it up was thinking of delete, meaning something taken away; in this case, butter.

In food manufacturing, starch often forms the basis of a product. ‘Your base starch as a viscosifier, which established your food’s structure’, one company explains. An example here might be a Catalan-style flan or French crème caramel, where starch replaces more expensive eggs, milk and crème. ‘Once you’ve created the structure with your base starch, co-texturizers [ another set of starches] fine-tune texture properties. They bring out the more subtle differences in texture that experience in our mouths while eating, such as mouthcoating [creamy] and meltaway [lusciousness].’

As well as offering cheap bulk and texturizing potential, starch has never been in such demand as it currently is to replace other nutrients. As health regulators have breathed ever so lightly down the the neck of the processed food industry to make its products healthier, reduction of fat, sugar and salt has become a regulatory religion, one that opens new doors for starch. Products can be reformulated, bumping up quantities of starch and cutting persona non grata ingredients, thus providing a justification for reduced fat and sugar claims on the label. Using starch, manufacturers can adjust the composition or ‘matrix’ of a whole host of processed foods, to recast them in a flattering nutritional light. Dong so ticks a few boxes with the public health establishment, and the sums also add up very nicely for manufacturers, as this starch company explains:

Our specialty solutions mimic the organoleptic qualities of fat, delivering a creamy, luxurious texture and smooth, glossy appearance in better-for-you applications. We’re also skilled at replacing costly tomato solids. Whether you are looking to replace oil, cream, milk, milk solids, vegetables or egg, we an ensure premium quality and guilt-free indulgence at a competitive price.

And when it comes to starch, ingredient savings are no idle promise. A high-performance starch can replace fat at a ratio of 10:1 in dips, dressings, soups and mayonnaise for a lower calorie, low fat label at lower cost. Starch can stand it for 30% of the cream in a ready made spaghetti carbonara and make redundant at least 35% of the tomato paste  otherwise needed to make a credible pasta sauce. It allows manufacturers to reduce the margarine in puff pastry by a fifth. A starch developed using a ‘cling optimized texture system’ will even have the necessary adhesion, viscosity and suspension to replace ‘up to 40% of the tomato/ vegetable solids in soups and solids’.

On a factory scale, using starch makes for massive savings. To achieve this end, mimicry lies at the heart of food manufacture, a constant itch to make not a faithful version of the real thing, but something that passes for it. For food technologists and new product developers, all the fun with food comes when you take it apart, break it down into components, then reassemble it in a more lucrative. Easy-to-process form.

Greek yogurt is a case in point… which between 2008 and 2012 achieved a spectacular sales curve. Sensing an opportunity, many companies wanted to get in on this dynamic sales sector but they faced a stumbling block.. When produced in the traditional way, Greek yogurt takes a whole lot more more milk to make, different equipment and factory set-ups than standard yogurt.

The starch manufacturer Ingredion first mapped the sensory attributes of Greek yogurts on the market: qualities such as ‘jiggle’, ‘slipperiness, and surface shine. It then devised an innovative starch, which it claimed can give ‘ a similar texture and eating experience to the market leading product’, yet it is much cheaper to produce because it uses less milk and can be made using the standard high temperature/short time non-Greek method, without any investment in new equipment. With this fabulously functional starch, Ingredion promises that yogurt manufacturers ‘can get to market faster, and produce product at lower overall cost’.

How does fast-track Greekish yogurt compare in taste to the genuine article? Because most such products are not sold as natural, plain yogurt, but with added flavors and sweeteners, we rarely have the opportunity to compare like for like. However, it is common knowledge in the processed food industry that starch can import unwelcome flavors. As one authority notes: “cereal-based starches such as corn and wheat starch are sometimes considered to have off-notes described as ‘cardboard’ or ‘cereal-like’. Fortunately for manufacturers, because most processed foods have multiple ingredient formulations., they can make sure that off-tastes are routinely drowned out by other flavors.

Even companies that make starches don’t attempt to sell their organoleptic qualities. To do so would be a waste of time, because they all understand that starches taste, at best, of zilch. Instead they try to make a virtue out of nothingness. ‘The bland taste of potato starch allows whole meat products to maintain their natural palatability’ is how one starch company puts it. A more forthright version of the same message might read ‘the boringness of starch won’t interfere with other ingredients.” They are used as fillers, stabilizers, thickeners, pastes, and glues in dry soup mixes, infant food, sauces, gravy mixes etc.

And if the addition of starch means net loss of flavor, it also translates into a net loss of nutrition also, because when highly refined starches of the type used by food processors replace proteins, fats,  fruits and vegetables, they actually worsen the nutritional profile of the resulting product.

Now this might sound counterintuitive if you’ve paid attention to the standard government nutrition advice: “Rather than avoiding starchy foods, it’s better to try and base your meals on them, so they make up about a third of your diet.’ In recent times, starchy foods, even the most refined types, have been hyped by public health agencies. Starchy foods such as cereals, pasta and bread, we are told, ‘are a good source of energy and the main source of a range of nutrients in our diet. As well as starch, they contain fiber, calcium, iron and B vitamins.’ This presentation of starchy carbohydrate as a hero nutrient is highly debatable. If we are going to champion certain foods on the basis of micronutrients, such as iron and B vitamins, then meat would be a better bet because it contains them in greater abundance. As for fiber, we can get all we need vegetables and fruit.

Of course, starchy carbs in their whole, unprocessed forms do contain some useful micronutrients, but the same cannot be said for the refined sort, which would be more accurately described as stodge, or fodder. Refined starches are rapidly broken down into simple sugars and readily absorbed into the bloodstream. This is why, if you chew a bit of white bread for a few seconds longer than usual, it will begin to taste sweet. Refined carbohydrates cause spikes in blood sugar and insulin levels, which encourages our bodies to produce and store fat. Long term, this predisposes us to chronic disease. Due to their smaller particle size, highly processed, chemically or physically altered starches –precisely the type used in food processing –cause an even faster rise in blood sugar. So when food manufacturers brag about reducing sugar –on the surface, a noble mission –it is worthwhile noting that if starch is the replacement, then this is a case of more of the same. Think of it as a gesture, a tactical, piecemeal reformulation that should not be mistaken for a radical one.

In so many ways, starch is a never-ending source of inspiration to food manufacturers. Classless starch finds a role in every echelon of food processing. It’s facelessness allows to go everywhere and anywhere.

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Controversy over chemicals used in packaging , such as bisphenol A and phthalates, has been aired or decades, but the same cannot be said for nanoparticles, an emerging technology. Nanoparticles, which are far too minute to see with a microscope, are derived from materials such as clay, silver, titanium, silica and zinc oxide, and increasingly used in food and drink packaging. They can improve certain ‘smart’ functions: extending the shelf life of food by decreasing the permeability of plastics, acting as ant-bacterial coatings, or making packaging lighter and stronger. Nanosilver, for example, is used to coat plastic food containers so that anything stored within can be sold for longer. Nanoclays can be incorporated into the fabric of plastic bottles to prevent oxygen from migrating through the walls and shortening the shelf life of the contents.

A boon for the food industry and consumers, surely? Unfortunately, it looks as if nanoparticles can also leach from packaging into food and drink. Researchers recently found, for instance, that aluminium and silicon nanoparticles migrated from plastic bottle into an acidic medium – of the kind you find in fizzy drinks and juices p- and that this migration increased with time, and at higher temperatures.

The potential health problems with nanoparticles is their minuteness. They ate about one ten-thousandth the width of a human hair, which makes them more reactive and more bioactive than larger particles of the same substance. This means they can end up in places that larger particles would not – our cells, tissues and organs, where they can accumulate to ill effect Nanoscale zinc oxide, for example, has been found to cause lesions in the liver, pancreas, heart and stomach of laboratory animals. The European Commission’s Scientific Committee on Consumer Safety has warned that ‘clear positive toxic responses [in some of these tests] clearly indicate a potential risk [of nanoscale zinc oxide] to humans. Other research suggests that nanoparticles of titanium oxide can damage DNA, disrupt cell function, and interfere with the defense activities of the immune system. One emerging scientific theory is that nanoparticles absorbed in the gut may be a factor in the growing prevalence of inflammatory conditions such as irritable bowel syndrome ,and Crohn’s disease.

The European Commission cites evidence from laboratory studies that nanoparticles can promote clumping of protein molecules, a factor in a number of medical condition. It also acknowledges that they can be transported from the upper lining of the nose [by inhalation] into the lungs and brain, a particular hazard for factory workers who have to handle nanomaterials. “Full evaluation of the potential hazards is still to come’, the European Commission reports, in a vaguely promising way,. In the USA, the National Academy of Sciences is far more impatient and warns that ‘critical gaps’ in understanding nanoparticles have been identified but ‘have not been addressed with needed research’. Basically, nanotechnology is out and about, and in contact with our food and drink. Regulators have been caught on the hop. The Institute of Food Science and Technology has expressed concern that

There does not appear to be a requirement for the supplier to specify the inclusion of nanoparticle in packaging materials and neither, due to the lack of end-product labeling requirements, is the consumer likely to be aware of the composition of the packaging material.

About 400-500  nanopackaging products are estimated to be in use now, and nanotechnology is predicted to account for 25% of all food packaging by 2020. In fact, packaging is just the advanced guard for this novel technology; nanotech additives are already out inforce on U.S. shelves. Nanosized titanium dioxide, for example, is now turning up in products such as coffee creamer, cookies, cream cheese, turkey gravy, lemonade and chocolate. Fresh fruit and vegetables can also be coated with a thin, wax-like coating, containing nanoparticles, to extend shelf life.

Could nanotech additives also be in the UK and European food chain? The truth is no-one really knows, and there has been no legal obligation on food manufacturers to inform us of their presence . . .

Who doesn’t know someone with a food allergy, or asthma, or irritable bowel syndrome, or with cancer, for that matter? Closed-minded toxicologists refer back to the philosophical musings of Paracelsus to justify an accommodating attitude to toxic compounds in our food chain and environment as they examine each one in splendid isolation from the safe confines of the laboratory. The rest of us, however, are right to question the comforting pronoucement of the imperturbable Paracelsus, frozen in the 16th century, that small doses of poison  do us no harm. We can be open-minded enough to consider the very real possibility that by activating, blocking, hijacking or otherwise messing with the normal functioning of our bodies, engineered chemicals are contributing to a wide range of human health problems, including obesity, diabetes, cancer, cardiovascular disease, infertility and other disorders of sexual development. And if we do take this proposition seriously, then reducing our exposure by minimizing the amount of packaged food and drink we consume is one obvious place to start.


1 comment:

  1. Now this might sound counterintuitive if you’ve paid attention to the standard government nutrition advice: “Rather than avoiding starchy foods, it’s better to try and base your meals on them, so they make up about a third of your diet.’

    ReplyDelete