It's getting difficult to define "snacks." As they continue to replace traditional meals, the category has gotten so all-encompassing that it's almost synonymous with "grocery."

Between that and the maturity of the category, growth is slowing. Snacks are no longer the holy grail they were two years ago, when they were pursued by all large, multi-category food companies.

Nevertheless, in the waning days of 2017, two significant acquisitions took place in this space. Campbell Soup got its toes wet in the space with the $4.9 billion purchase of chip-and-pretzel maker Snyder's-Lance. Hershey Co., with lots of sales in the candy part of the category plus a 2015 beef jerky acquisition, bought Amplify Brands, maker of SkinnyPop and other snacks. A month earlier, Mars Inc. made an equity investment in No. 3 snack bar maker Kind LLC—which, despite not changing its corporate name, has been referring to itself as Kind Healthy Snacks.

Still, as Nielsen defines it (see graphic) snacks is a $93 billion category. An interesting sub-category, according to Nielsen, is single-serve snacks, a category that saw $33 billion in sales in 2017. Annual household spending on these grab-and-go products increased 1.1 percent to $133 per household; but more importantly almost every household (98 percent) in the U.S. purchased these items at least once for quick and convenient consumption. Busy households buy them almost twice monthly (22.3 times per year) across categories, says Nielsen. Large families—specifically with five or more members—index the highest out of all household groups, purchasing 16 percent more individually packaged snacks than the average family.

Even meat snacks, which have been enjoying 7 percent annual growth rates for the past four years, appeared headed for half that rate in 2017.

Jerky and meat snacks, like the protein-packed cuts of preservative-free meats from Jack Link's Lorissa's Kitchen's (lorissaskitchen.com), cater to the growing snack-as-mini-meal trend, as well as the lingering interest in protein. Hormel's new Natural Choice snacks in four varieties combine cheese cubes, ham, roasted chicken or turkey and dark chocolate-covered pretzels, nuts or blueberries, for a small indulgence. "Our 100-percent natural deli meat is now available in a convenient, portion-controlled option, coupled with a sweet treat, attributes our wellness-seeking consumers have long been craving." says Andrew Quinn, brand manager at Hormel Foods (www.hormelfoods.com).

Jerky plus nuts and even dried fruit are mixed into PowerBar's (www.powerbar.com) new Jerky & Nut savory snack bars, each of which packs 10g of protein into original, barbecue and teriyaki varieties.

Consumers still appear to want healthier snacks. Plant ingredients figure prominently, with rediscovered plant protein sources showing up in chips, such as Beanitos, which forges pinto and black beans into chips, Plentils lentil-based chips from Enjoy Life Foods and Hippeas organic chickpea puffs.

Some more traditional plants – we're talking cherries, mangoes and apples – are the sole ingredients (with no added sugars) in Kind's Fruit Bites, which were launched last year. The company also debuted Pressed by Kind bars with only fruit and vegetables or chia seeds.

Non-GMO snacks are especially popular, with an 18.2 percent sales hike in each of the past five years, followed by snacks free from artificial colors/flavors (up 16.2 percent) and no-/reduced-sugar claims (up 11.3 percent), according to Nielsen.

Farm & Oven Snacks (farmandoven.com) has managed to sneak veggies and probiotics into tasty baked cookies. New Bakery Bites, in flavors such as chocolate beet dark chocolate, zucchini lemon poppy seed, carrot cinnamon and pumpkin maple pecan, contain 40 percent of the recommended serving of daily vegetables and 1 billion probiotics per package. "None of my three kids likes veggies," says Kay Allison, bakery co-founder. "So, when my son begged for my pumpkin bread, I added more pumpkin as a way to get him to eat a few more veggies."

While interest in simple, wholesome snacks is up, consumers still make room for indulgent treats. "Consumers talk about eating healthy as a presentation of their best selves and their aspirations, but in reality, they simply want something that tastes good," said Jeanine Bassett, General Mills' vice president of global consumer insights.

Nuts and seeds

Perennial favorites snack mixes and nuts have a "health halo," are portable and come in numerous on-the-go varieties. Over the past year, consumers have asked for exotic, innovative flavors and options with a bit of indulgence.

PepsiCo's Frito-Lay division (www.fritolay.com/snacks) is launching new Doritos Crunch Nuts and Crunch Mix, portable peanut-based snacks in handy on-the-go standup pouches. Frito-Lay is also making its snacks healthier while balancing flavor and nutrition in new items like Simply Tostitos Black Bean tortilla chips, which incorporate legumes, pulses, 4g of protein and 5g of fiber per serving.

Texture is in, as companies like General Mills (www.generalmills.com) are using it in new ways. Its new Nature Valley Layered Bars blend three textures, including layers of crunchy granola, nuts and creamy chocolate and a choice of almond butter or peanut butter.

Product claims such as "reduced sugar," "no preservatives," gluten-free and "organic" also are driving sales. Enjoy Life Foods' (www.enjoylifefoods.com) free-from, vegan Grain & Seed bars are made with three types of sorghum, plant-based protein and what the company says are Purity Protocol-certified gluten-free oats.

Simpler, healthy ingredients and gluten-free flours and ancient grains are finding their way into crackers, cookies and even frozen pizza rolls. Smart Flour Foods' (smartflourfoods.com) new Snack Bites are a clean-label twist on old-time favorite pizza rolls. They're made with ancient grain-based ingredients, real cheese free from synthetic hormones and uncured meats free of gluten, nitrates and nitrites. CEO Charlie Pace, who is gluten-intolerant, says he wanted to provide a wholesome, innovative and cleaner take on a popular snacking favorite.

With new portions, benefits, flavors and conveniences, snacks are here to stay, prompting more snack development and broader definitions of snacks to be consumed more often.

The other plant-based contribution

Many consumers are seeking healthier snacks. In the case of salty snacks, that can mean less oil and sodium in the finished goods. The manufacturing side can help.

Centrifugation is one way to lower oil content in potato chips and other fried foods. As much as half of the oil can be removed by spinning chips at a g-force of 5-8. The potato slices might need to be thicker to reduce breakage, and the addition of heat can lower the centrifugal force needed to reduce surface oil 33-50 percent.

Modest oil reductions are realized with vacuum frying, but the primary benefit of that technology is reduced levels of acrylamide. With the European Commission poised to set benchmark levels of acrylamide in potato chips and French fries, as well as soft breads, breakfast cereals, roasted coffee and other products, vacuum frying becomes a more viable process.

The European Commission has approved guidelines for the levels of acrylamide, which is created when the amino acid asparagine reacts with food sugars at temperatures above 248°F/120°C. Those guidelines could become mandatory limits as early as spring 2018.

Following the lead of the World Health Organization, California’s Office of Environmental Health Hazard Assessment declared the chemical a carcinogen subject to disclosure under the Safe Drinking Water and Toxic Enforcement Act of 1986, commonly known as Proposition 65.

Dutch equipment manufacturer BMA Nederland BV introduced a vacuum fryer in the 1960s, though interest languished until acrylamide emerged as a concern in 2010. BMA’s fryer resides inside a vacuum tube and allows process temperatures to be lowered sufficiently to preempt caramelization of sugars. Throughput is an issue: A unit measuring 40 ft. in length operates in batch mode, producing about 600 lbs. of finished product per hour. Servicing the unit requires removing the fryer from the vacuum tube.

Heat and Control Inc. (www.heatandcontrol.com) was the first domestic OEM to fabricate a vacuum fryer, introducing the unit in 2011. A rotary valve at the infeed and a series of locks at the discharge allow continuous processing while maintaining pressure of 80-100 millibars—about 1.5 psi, or one-tenth atmosphere. Heavy gauge steel is used to prevent the fryer from collapsing into itself.

“These are not inexpensive systems,” understates James Padilla, a food scientist with the Hayward, Calif., equipment supplier. Recently commissioned fryers sold at several multiples above the cost of conventional fryers, relegating vacuum frying to niche applications.

A Korean processor working with a potato prized for its golden hue opted for vacuum frying because it results in little color change. Another processor using “designer oils” from avocados and olives employs the technology because it removes oxygen and prevents rancidity from those unstable oils.

A more practical acrylamide solution is electroporation. Pulsed electric fields (PEF) are applied to potatoes pre-frying, with the rate and current level determining the size of perforations created in the potato’s cell walls. Microbiologists use PEF to allow DNA and other material into a cell; in potato processing, permeability allows asparagine to wash out of the cell.

Heat and Control calls its system E-Flo and cites improved chip crunch, taste and texture as well as reduced acrylamide formation and oil content as its benefits. Half a dozen E-Flo systems have been commissioned in the European Union to date, and strict limitations on the chemical could spark a surge in demand.

Biological, not mechanical, interventions could be the go-to solution to acrylamide if ice cream processing is any guide. The shear and pressure exerted on low-fat milk with low-temperature freezing imparts a full-fat mouthfeel in ice cream, but the same effect is possible by including additional ingredients to preempt capital outlays.

Denmark-based Novozymes introduced an enzyme solution that reduces acrylamide in starchy baked and fried foods a decade ago. The firm claimed the enzyme reduced levels up to 90 percent by consuming the precursor amino acid. Depending on whether it would be considered a processing aid or an ingredient, its use could thwart efforts to create clean ingredient labels.

Taking direct aim at French fries, the Norwegian firm Zeracryl AS uses lactic acid bacteria and other compounds to trigger fermentation that converts simple sugars into lactic acid. Some strains also consume asparagine, the firm claims, further deterring the formation of acrylamide.

In an acrylamide guidance document, FDA notes the addition of amino acids can reduce chemical formation, but negative impacts on product quality are not uncommon. A Vancouver R&D firm took an approach not considered by FDA: a modified bakers’ yeast that consumes asparagine before the amino acid can react with reducing sugars to form acrylamide. “People understand yeast and are comfortable with it,” points out Matthew Dahabseh, chief science officer at Renaissance Ingredients Inc. (www.renaissancebioscience.com). His firm’s yeast also is non-GMO.

Besides high heat and asparagine, moisture content also is a factor in acrylamide formation, with crackers and other low-moisture baked goods more susceptible to the chemical reaction. Wheat germ also is a factor. Patent flour contains little or no wheat germ, so acrylamide formation is in the 10-20 parts per billion (ppb) range. Whole grain bread, on the other hand, contains 75-200 ppb, and those levels are elevated when it is toasted.

While yeast isn’t used to make potato chips or French fries, Dahabseh says his product can be used in solution to soak potatoes pre-frying. The result is surface degradation of asparagine, where the Maillard reaction occurs. Presoaking for 25-30 seconds reduces acrylamide formation 75-80 percent in French fries, he says.

Renaissance is investigating the yeast’s efficacy in treating green coffee beans. Acrylamide levels of 10 ppb have been found in beer, but the chemical isn’t a concern in beverages and other liquids.

Orkla Food Ingredients in Oslo,Norway, is commercializing the yeast under license in Europe. “They totally expect mandatory levels for acrylamide are coming,” reports Dahabseh.

Acrylamide wasn’t on anybody’s radar when the creators of Bare Snacks (www.baresnacks.com) were developing a process for crunchy apple chips. Oil pickup made frying a nonstarter; instead, a multi-stage baking process was developed for a line that now includes coconut and banana chips.

“Almost all banana chips on the market are fried in palm oil or coconut oil,” notes Santosh Padke, CEO of San Francisco-based Bare Snacks. “Fat masks their natural flavor, so banana flavoring is added after frying.” Those chips have calorie counts well above the 120 calories per serving in Bare Snacks.

“Many consumer engagements start in coastal communities, and we are cognizant of acrylamide concerns and are keeping track of developments,” Padke adds. However, he doubts Bare Snacks’ products are candidates for acrylamide formation.

“Healthy snacking used to be an oxymoron,” he concedes, but millennials and health-conscious consumers now expect their minimally processed snacks to taste great. Based on his firm’s 30 percent-plus sales growth in recent years, Padke believes Bare Snacks is delivering on all three fronts.