"HPP is a big part of our focus going forward with new chef-quality product lines," says Meadows. In fact, it has been a big part of the reason the company was able to undertake a major expansion into upscale products, such as new seasonal convenience items and newly minted brands including Fresh & Delicious, Café Style Fresh Soup and Pacific Coast Cuisine. The last, for example, was introduced in October and features such treats as Cajun Crab Dip and Honey Smoked Salmon Dip.
"If you've never had a chicken salad with no preservatives — fresh, free-range or hormone-free chicken — there's nothing like it," Meadows says. Such entrees and the higher-end meat are aimed at upscale customers who seek "an ultra-fresh product with tremendous taste, without the need for preservatives. It's given us the ability to take that next step into healthier ingredients and food safety for our customers."
The system installed at Sandridge was supplied by NC Hyperbaric (www.hiperbaric.com) of Spain, and installed by Gridpath Solutions (www.gridpathinc.com), Stoney Creek, Ontario, which handled the turnkey installation. This included the HPP unit, associated infeed and discharge systems and a supervisory monitoring and control system with a local operator station. The automation system manages the both mechanicals (valves, actuators) and key parameters (time, temperature, pressure, etc.). The system also contains safety measures so, for instance, it will not allow discharge valves to open or the process to be manually stopped if safety processes have not been properly completed.
The process is relatively straightforward: Finished products already prepared in the facility, such as pouched salad or product in plastic trays or sealed containers, are taken from an infeed conveyor and loaded into four cylindrical carriers. These carriers are loaded into a high-pressure chamber that is sealed and filled with water to evacuate air. The chamber is then brought to pressures between 58,000 and 87,000 psi for up to three minutes, with water temperature below 45°F, to kill harmful bacteria. When the process is completed, the water is evacuated and the product carriers exit the chamber to be reloaded. Product is transferred for drying and final packaging.
The process specifics vary by product. For example, some Hormel vacuum-packed deli meats are subjected to 87,000 lbs. per square inch of water pressure to inactivate pathogens such as Listeria monocytogenes without harming the product's taste, texture or nutritional value. The company tried HPP on foodservice Bread Ready sliced meats products, and customer response was so favorable the company successively added Natural Choice retail products and many more products since to its HPP product line.
While ROI and payback financials are not disclosed, Pioske says the main benefit is that HPP opens a "whole new world for marketing and sales of fresh, healthier product" — that is, a broader market that will bring new sales and business growth.
Extended shelf life is not promoted by Sandridge as a headline benefit. That might be the first attribute many people in the industry think of when they hear of HPP. While it's true HPP can extend shelf life of Sandridge's potato salad and many protein salads to more than 60 days to eliminate "shrink" or losses for customers, "That's not what we're about when it comes to HPP," says Pioske. “HPP certainly does extend shelf life, but fresh is just too important to put in terms of 60 or 90 days. We want that consumer to enjoy that potato salad or other product within a few weeks — if not earlier.
“Certainly, our goal is to produce fresh, healthy products with healthy ingredients and get them to market while meeting supply chain needs." On that count, HPP is only one tool in the company's kit. A "Fresh Initiative" program with Pittsburgh-based Giant Eagle supermarket chain, for example, successfully replenished store shelves for the Pittsburgh-based Giant Eagle Supermarket chain within 24 hours of an order to reduce store shrink and eliminate as much as $200,000 in warehouse inventory costs.
Challenges remain in expanding HPP for mainstream processing. While the technology has proven beneficial in producing safe, high-quality products, HPP is only now maturing. Small-basket configurations have given way to larger, horizontal machines, but these still run in batch mode. While the company can run up to eight batches per hour of some products, throughput varies by product because some products and packages are better suited to the machine's cylindrical carriers.
"We can produce thousands of pounds more per hour of some products, such as salads in flexible pouches that conform to the shape of the HPP's round cylinder, whereas we might only be able to produce half that if we're processing meal trays or cups," Meadows explains.
Even though the company installed the largest system available at the time, such considerations have Sandridge ramping-up HPP operations a bit at a time. The current strategy is to reserve it for those high-end products that constitute roughly 10 percent of the company's total business. But these upscale products have the greatest growth potential, and they may well be the future of fresh, prepared foods.
See HPP in action at Sandridge Food Corp