Process and Operations / Food Safety / Technology

Manufacturers Look to Super-Premium Processing to Keep Beverages Safe

Technology is front and center as beverage processors respond to growing demand for fresh, minimally processed products.

By Kevin T. Higgins, Managing Editor

Fresh is in, as any juice processor can attest, with the number of juice-based beverages making freshness claims doubling worldwide in the past five years, according to research by Innova Market Insights.

Those products now account for 11 percent of all beverages on the market. Almost a third of the newer launches carry labels touting their preservative-free status, replacing previous standbys like “not from concentrate” (4.9 percent) and “real” (3.2 percent). “Raw” is another up-and-coming descriptor.

Preservatives are a particular no-no in the super-premium segment (products that retail for $9 or more for a 16 oz. bottle). An example is Rawpothecary, a Brooklyn-based juice processor that uses the term “cold-pressed” to describe the high-pressure processing (HPP) it relies on for shelf life in lieu of preservatives. HPP rarely is mentioned on product labels, although increasingly it is the technology of choice.

An even newer kid on the technology block is microwave. Aseptia Technologies and Industrial Microwave Systems both have microwave processing systems that aren’t compatible with solids but work fine with beverages and other pumpable foods. As they drum up processor interest in licensing microwave technology, the companies increasingly are targeting makers of super-premium juices and other beverages in tune with the clean label, no-preservatives demands of health-conscious Americans.

Noting the double-digit growth that has propelled beverages like Evolution and Odwalla in this $800 million-plus category, Aseptia’s Michael Druga, chief technology officer of the Raleigh, N.C., firm, says, “That is the wave we’re trying to leverage. Those drinks are entering the mainstream. It’s more of a trend than a fad.”

Aseptia refers to its sterilization process as volumetric heating, as opposed to the convective heating that is typical. As a fluid is pumped through the unit, it encounters parallel microwave energy that heats the fluid quickly and uniformly, avoiding the burn-on and destruction of nutrients that inevitably occurs when thermal energy must penetrate to a fluid stream’s cold spot, overcooking some of the volume in the process. Natural color and taste are retained, along with the antioxidants, proteins and other components that people are willing to pay a premium to get.

HPP also is a gentle process, Druga allows, but it only pasteurizes the fluid and requires refrigeration. The microwave technology is aseptic, resulting in shelf stability of about one year.

The bulk of today’s beverages are processed with direct steam injection or through plate heat exchangers. Besides destroying some nutrients, those technologies require considerably more energy than microwave, according to Druga. Aseptia owns and operates Wright Foods, a copacker that operates both steam injection and microwave production systems. Because of radiant heat loss in pipes, boiler inefficiency and the phase change that occurs when steam is created, “maybe 45 percent of the energy input is left in your stream for processing,” he says, based on a study at Wright Foods. Microwave, on the other hand, provides 97 percent heat transfer efficiency.

The technology got a boost recently with the introduction of a benchtop version of the microwave heat exchanger from another Raleigh, N.C., firm. Microthermics Inc. fabricated the scaleable lab unit in collaboration with Aseptia. A 20-second hold time is typical, according to David Miles, Microthermics vice president, and the absence of hot surfaces means less fouling and easier maintenance than with steam injection.

Squeeze harder

RTE meat pasteurization remains the bread and butter application for HPP, but premium juices, fortified water, chia seed drinks and other nutritional beverages account for a growing number of uses. The success of Evolution Fresh, the Starbucks-owned juice brand that promotes its use of HPP to retain natural flavors and nutrients, has helped spur interest in HPP.

Today, the nation’s newest HPP toller is exclusively processing natural and organic beverages, although that will change when USDA certification is attained. Denver-based Natural Food Works LLC, a two-year-old copacker specializing in organic foods, began offering HPP tolling in March, adding to competencies in baking, extrusion and dehydration.

“Natural and organic is a natural fit for HPP,” says Annie Hawkins, the firm’s business development manager. “The majority of consumers don’t know what HPP cold pasteurization is, they’re just happy their food doesn’t have preservatives.”

Referring to the Rocky Mountains region as “the mecca of the natural and organic world,” Hawkins says the emergence of “juice cleansing” is pushing in-container pasteurization with HPP to processing’s center stage. Consuming a plate of quinoa for breakfast and carrying a banana for lunch might meet with a nutritionist’s approval, but it’s far less convenient than slugging down a 16 oz. PET bottle of juice from fresh fruits and vegetables with all their nutrients intact.

Juice companies that use hot fill must reformulate to use HPP, but they are doing it, she explains, because “the consumer demand is to eat as fresh as we can, with all the nutrients together.”

HPP’s growing popularity for beverage processing represents a dramatic turnaround. HPP pioneer Avomex dabbled with the technology for juice processing, using the fluid itself in place of the water that typically is pumped into chambers and elevated to pressures of 85,000 psi and beyond to squeeze the life out of microbes.

The maker of Wholly Guacamole, which was acquired by Hormel Foods in 2011, abandoned the juice application because cleaning and sanitizing between product runs resulted in unacceptably low throughput. Loading bottled beverages or pouched liquids into carriers in the same manner that solid foods are handled resolved the issue and made HPP feasible for juice.

When new technologies move into the mainstream, production professionals prefer skid-mounted units on which they can run trials using their products. Microthermics’ microwave machine almost approximates that. HPP systems, on the other hand, are much too large to transport for demonstration purposes. That is about to change, thanks to the arrival of SSYH Technology Co. Ltd.., the U.S. division of China’s leading HPP machine fabricator. As Microthermics was showing off its microwave lab unit at July’s IFT Expo in Chicago, SSYH was introducing itself to the North American market several aisles over.

SSYH’s biggest HPP vessel has a capacity of 300 liters (79.2 gallons), considerably smaller than the 500-plus liter vessels from Avure Technologies and Hiperbaric USA. But the company also makes lab equipment as small as 1 liter and a 50-liter vessel that it bills as suitable for small-scale seafood processors.

Processors' wish list

Industrial microwave is too new to have been considered by the processing professionals who participated in drafting a white paper last year from the Food Processing Suppliers Assn.’s Beverage Council. Representatives of Coca-Cola, Nestle Waters, Campbell Soup Co. and other organizations came up with a 25-point wish list of equipment needs and functions they would like vendors to incorporate into the systems needed to produce the diverse beverages that the market is demanding. (Read Beverage Personalization and Its Impact on Processing and Packaging Systems for more information)

Faster cleaning and sanitizing of equipment to accommodate shorter production runs of diverse products is high on the list.

“Changeovers in excess of two hours need to be eliminated,” the report states. Besides machine design changes to facilitate faster cleaning, the paper advocates alternative cleaning solvents, including electrolyzed oxidative water. The water is created by introducing an electrical charge to water in the presence of salt, ionizing the water into two distinct streams of hypochlorous acid and sodium hydroxide for both cleaning and sanitizing.

Coca-Cola uses the ionizing generators, and the white paper quotes the testimonial of sanitarian Pete Duessel of Coca-Cola Refreshment: “Electrolyzed water has provided us with an effective, safe, green product that allows us to rapidly jump from one pungent flavor to another.”

Greater flexibility in equipment for blending, pasteurizing and packaging beverages also is a priority. “Processing systems must be designed to handle products from clarified juice to smoothies with pulp and particulates,” the report states. “Some new (beverage) products need specific equipment and exotic metals for high temperature, high salt and high heat products,” and that requires robust, industrially hardened equipment, the panel concluded.

Equipment that does double duty exemplifies flexibility. Council member Andy Juarez cites his experience with sanitary twin-screw pumps to illustrate the point.

“Piece identity” has emerged as a priority in the juice world, and processors need gentle handling by pumps and other equipment to deliver smoothies and other drinks with recognizable particulates. If their diversified product portfolio also includes clarified juices, processors also need high-volume pumps. At Selah, Wash.-based Tree Top Inc., where Juarez serves as vice president-engineering, that meant maintaining both progressive cavity pumps for solids and rotary lobe pumps for simple juices.

“Twin screw is very flexible technology that gives you the best of both worlds,” says Juarez, providing a wide range of pumping volume. “The piece identity is comparable to progressive cavity, but it doesn’t have a stator that wears out, like a progressive cavity.”

Two vendors manufacture twin-screw pumps, including Axiflow Technologies Inc. in Lutz, Fla., and ITT Bornemann GmbH, a German OEM that notes there is no metal-to-metal contact in its self-priming pumps, which offer “compete axial balancing of the rotating elements.”

“If you want good piece identity, you need the right heat exchanger and the right pump,” Juarez concludes. “Ultra fresh, minimally processed juices are a little more taxing on the equipment,” but simply adding specialized equipment to accommodate them is not an option.

Whether the answer is heat exchangers with multi-tube bundles, HPP or other processing units, manufacturers are searching for solutions that are easy to maintain and capable of producing a wide range of beverages.