We all want foods and beverages with great mouthfeel and taste, but don't want to fill up with fat, calories and sugar. Product developers recognize that low-fat, high-fiber and low carbs are critical factors today for baked goods and snack formulations.
Starches can help. Starch can be extracted from more than 50 types of plants and supports sauces, puddings, pie fillings and soups. Starch may also be added to frozen products to prevent them from dripping when defrosted.
But not all starches are created equal. These polysaccharides vary widely in quality, granular shape, size, amylose content and viscosity and in how they thicken and flavor the finished products.
Most are made from grains, roots or tubers. The most common forms of grain starches are wheat flour and cornstarch. Starch can be waxy, modified for more functionality or resistant, which can't be digested because it's composed of partly milled grains and seeds. As its name suggests, resistant starch resists digestion in the small intestine and passes through the body without entering the bloodstream or breaking down into glucose, as most other foods do.
Heat-stable in most conventional cooking operations, resistant starch can be used as an ingredient in a wide variety of conventional foods.
Used in practically all food starch applications, modified starches act as thickening agents, emulsifiers and stabilizers. Bonded with phosphate, modified starch can absorb more water and keep ingredients together. Modified starches are obtained from native starches as a result of physical, enzymatic or chemical processing methods.
Developed in the 1950s with the onset of fast and convenient foods, modified starches serve a number of functions. They offer superior thickening, increased paste clarity, stability in refrigerated and frozen storage, as well as resistance to mechanical shear, high temperatures and retort processing, and they improve adhesion and texture.
They can emulsify salad dressings by enveloping oil droplets and suspending them in liquid, such as vinegar. Acid-treated starch forms the shell coating of jelly beans. Oxidized starch increases the stickiness of batter.
Modified starches are often recommended for challenging process conditions (pH, temperature and shear) and longer shelf stability when developing unique and differentiated textures or cost-effective solutions, points out Marcelo Nichi, senior manager marketing texture at Ingredion (www.ingredion.com), Westchester, Ill. "Modified starch is used in different applications because of its functionality and process tolerance. It usually provides excellent cost-in-use, higher flexibility and breadth of applicability."
Modified starches also better withstand harsh thawing, pressure, heat and other processing rigors and help extend the shelf life of products. The major raw materials for modified starch include corn, tapioca, amylose, potato and wheat.
Native starches are untreated and include corn (dent or field corn, waxy maize, high amylose), potato and tapioca. All native starches are allowed for use in food, but the range of chemically modified starches is restricted for food use. The use of native starches from plants is on the rise, as food developers and manufacturers replicate the properties and functions of wheat for gluten-free applications, which hasn't always been easy to do.
"The increased use of native starch is driven by the development and promotion of clean label, functional starches, which are physically modified to alter their rheological properties," explains Mel Festejo, COO at American Key Food Products (akfponline.com), Closter, N.J. "These clean-label starches, being developed from corn, tapioca, potato and even peas, ultimately have enhanced functionalities."
Native starch is being added to bakery products, snacks, batters and breadings, says Angelina De Castro, Ingredion's senior manager of North America wholesome innovation. "Native starches can be used in canned products, processed meats, noodles and pasta and dry mixes. Rice, potato and tapioca starches are highly used in gluten-free products. But unmodified, native starches inherently have little process tolerance and break down easily under conditions of heat, acid and shear to yield very low viscosity and undesirable textures. They also have very poor freeze/thaw stability, resulting in either a grainy or a gelled texture with a lot of syneresis."
That's where the company's Novation functional starches come in. Prima 650, Ingredion's first clean label starch with moderate process tolerances, combines instant viscosity with higher texture stability and can help keep shear low while extending texture stability over a finished product's intended shelf life by more than 25 percent.
Clamor for clean-label
As consumers have grown more health conscious, clean-label alternatives to modified starches are being developed to provide the same functionality as conventional starches, perhaps at reduced costs.
"In the last few years, the clean-label trend has produced starches by physical or non-chemical modification [to achieve] properties similar to chemically modified starches," points out Ody Maningat, vice president of R&D and chief science officer at MGP Ingredients (www.mgpingredients.com), Atchison, Kan. "Current clean-label and health and wellness trends are driving some of the texture enhancement of native starch. Native starch has a labeling advantage. It has functional roles in clean label food products that demand more free-from, organic and 'natural' ingredients. However, product developers use starch for a number of reasons, including increased binding, thickening, texture or for storage stability. Therefore, modified starch applications in the food industry are likely here to stay," he says.
Resistant starches perform as a source of dietary fiber in formulations that require "good" or "excellent" sources of fiber claims. They also help with, calorie reduction and beneficial physiological effects, Maningat adds.
To achieve crispness, a highly desired textural attribute in snacks, deep-fried, coated foods and breakfast cereals, Maningat suggests using resistant wheat starch, such as MGP's Fibersym RW. "Fibersym provides textural enhancement and a health and wellness contribution. Starch scientists have also developed physically modified starches using heat treatment. These heat-treated starches behave like chemically modified starches and are very popular in clean label food applications as they are simply labeled as 'starch,' preceded by their botanical source."
Consumers prefer a neutral or bland taste in starch, Maningat says. "Traditional sources of starch from corn, wheat, tapioca and potato have acceptable taste. Wheat starch, in particular, has a clean and neutral flavor that matches very well with bakery, cereal, pasta, noodle, and other flour-based products."
Ingredion says Novation starches allow product developers to create products with a rich texture and taste but work with simpler, clean-label recipes and ingredients consumers recognize. "Clean label is one of the main themes and occupies a central role in several manufacturers’ strategies," De Castro emphasizes. "The clean label trend appears to reflect a wider consumer desire to return to a more authentic way of eating. Consumers want minimally processed foods, more authentic and real ingredients, no synthetic additives, no unexpected allergens and no hormones or antibiotics. We are driving innovation with functional native starches and functional native flours, which generally have a positive consumer perception and are widely accepted as clean-label ingredients."
A key challenge is that clean-label starches must deliver the taste and texture consumers are accustomed to experiencing, she observes. "That means functional native starches used in clean-label formulations need to be robust and deliver functionality equivalent to conventional modified food starches established as industry benchmarks."
Industry and consumer pressures have prompted some manufacturers to search for starches with functionality for gluten-free, free-from, non-GMO and low-calorie products. A gluten-free product would be better served with tapioca or corn starch instead of gluten-containing wheat starch, for example.
"We see gluten-free starches as part of better-for-you attributes and clean-label messaging," says De Castro. "Ingredion has developed a broad portfolio of products and capabilities to address the gluten-free market. It's still growing by double digits."
Though it behaves differently and has different properties than grain starches, arrowroot starch has been around for years. It all but disappeared for a while, as advances in flour and starch technology with wheat, corn/waxy maize, potato and tapioca took hold. Arrowroot made a bit of a comeback in the gluten-free market and is gaining uses in the baking industry.
"With the increasing awareness and popularity of non-GMO ingredients, suppliers are looking at non-traditional or marginal sources of starch, such as arrowroot," explains AKFP's Festejo. "Gluten-free products are no longer just a marginal niche but have become mainstream. Some businesses that were marketing conventional wheat-based products succeeded in developing gluten-free versions and then decided to focus on the latter to satisfy both conventional and gluten-free target markets."
Product developers are also rediscovering pea and tapioca starches for their functional properties and potential health benefits. "Pea- and tapioca-based starches not only delivery thickening, process tolerance and stability, but can be cost-effective alternatives to more expensive ingredients," adds De Castro.
Tapioca starch is also gluten-free, and is a resistant starch, with thickening properties that can help people feel full, so could be a key to controlling weight.
"Pea and tapioca starches are non-GMO ingredients," Festejo says. "Pea starches are viable by-products in the manufacture of pea protein. Demand has gone through the roof because of its superior amino acid profile and its non-allergenic nature. And pea starch has certain characteristics that can substitute for modified starches. One big factor in pea starch's strong functionality is that it has the highest amylose/amylopectin ratios among all native starches."
Tapioca starch is adept where relatively lower gelatinization temperatures, bland flavor, crisp textures and improved freeze-thaw functionalities are preferred, Festejo adds. "Tapioca starch is based on the cassava root, cultivated in high quantities in different regions of the world, making its supply and pricing fairly stable. AKFP has launched a premium cassava mix, blending native and functional/clean-label tapioca starch. The original application for this is Brazilian cheese bread. The mix yields the same quality and texture of the original delicacy, and can be used for gluten-free/ paleo-friendly baked products."
Rice is the preferred source of starch for Beneo Inc. (www.beneo.com), Morris Plains, N.J. Rice starch can prevent breakage associated with many gluten-free baked goods and can substitute for wheat flour in cakes and breads, says President Jon Peters. Its high amylose content provides crunchiness, and it can also help extend shelf life.
"Consumers are increasingly making food and beverage purchase choices that lead to healthier lifestyles," says Peters. "Therefore, manufacturers are looking for ingredients that meet consumer expectations. Our native and modified rice starches help achieve more functionality in terms of texture and body. Technical trials confirm Beneo's Remypure rice starch qualifies for clean-label status without the use of chemicals. Being gluten-free, it works well in applications in such as savory sauces, ready meals and bakery items."
Used in fruit preparations, it shows improved viscosity buildup equal to chemically modified starches, he says, and has a clean, fruity flavor. "Stable under severe processing conditions, the starch was tested to tolerate acidity and heat well for applications such as jarred baby food, sauces and dairy desserts," says Peters. "Thanks to Remypure’s new thermal production process, the starch performs comparably to chemically modified food starches without using any chemicals."
A starch that turned some heads at the recent Institute of Food Technologists' Food Expo is green banana flour. One example, NuBana P500 from International Agriculture Group (www.iagnubana.com), Mooresville, N.C., is a functional, pre-gelatinized flour made from green bananas that thickens in cold water. NuBana can replace hydrocolloids and stabilize fruit systems. Helping replace sugar by replacing bulk, it's gluten-free, clean-label and 100-percent fruit ingredients. NuBana is produced when starch content is at its highest, so it's rich in amylopectin.
Unripe bananas boast high levels of resistant starch, often prized by dieters because it helps them feel full. The ingredients in NuBana are also high in potassium and magnesium.