The devastating 2018 E. coli outbreaks linked to California-grown romaine lettuce drove home the point yet again: food safety is job No. 1 for growers, processors and marketers of bagged salads.

Fortunately, suppliers and third-party specialists continue to develop new technologies and protocols to keep future outbreaks to a minimum and to limit their impact when they do occur.

San Jose, California-based traceability technology provider Zest Labs Inc.’s customers in the leafy greens industry face substantial challenges when it comes to making sure product is brought to market in time to ensure long shelf life, says Peter Mehring, Zest Labs’ CEO.

“Their challenge is the variability in harvest process and weather,” Mehring says. “Any variability in timing from how it is in the field, how it’s brought in, how it’s processed.”

Harvesting in the warm climates of California and Arizona significantly impacts freshness and shelf life. Complicating matters, product quality or other problems related to timing can’t be seen in the first 24 or 48 hours after product ships, Mehring says.

That means the problem isn’t found until a supplier hears about it from a retailer or, even worse, a consumer. That’s where Zest Labs and its traceability technology come in.

Customers place Zest Labs sensors on every box or bin in the field after leafy greens have been harvested. The sensors automatically record when product is harvested. Then, throughout the supply chain, that box or bin can be traced automatically, without bar codes needing to be scanned.

“The variability they find is eye opening,” Mehring says. “It’s like traffic. When utilization is at 50%, things flow smoothly. But then you get peaks of 80 to 90%  utilization, or even over 100%, sometimes when the weather changes. You can’t harvest for two days, then you have to catch up, then everything backs. Then, how you handle things becomes critical to eliminate bottlenecks.”

The visibility provided by Zest Labs’ sensors helps shippers prioritize based on how fresh product is. Within the leafy greens category, that can be especially critical for bagged salad producers, Mehring says.

“Bagged salads typically contain two or more kinds of leafy greens,” he says. “And those different greens are coming from two very different fields. Even if they’re harvested on the same day, they can have very different experiences and shelf lives.”

Bagged salads, as Mehring points out, are only as good as their weakest ingredient. In addition, once lettuce is cut, its edges oxidize faster — much faster than an uncut head of lettuce.

The results of using technology like Zest Labs’ sensors can be dramatic for leafy greens growers. With one customer, Zest Labs saw average shelf life climb from six to “well over” 18 days, Mehring says.

Commissaries and central kitchens can benefit significantly from traceability technology in leafy greens production, Mehring says.

“Commissaries are often getting leafy greens in bulk and partially processed — a 10 lb bag of shredded lettuce, for example,” he says. “Knowing all about how it’s processed, how it’s aging — they don’t typically get that visibility. If you don’t have the data built in, you can’t inspect for it, you can’t screen out for quality control. It has to be built in so you can run it at the speed of commerce. Suppliers are often blown away by the visibility we give them, and they can use that to deliver more consistent quality, and they can communicate the data at the time of shipment.”


Top quality meets cutting-edge food safety

To help ensure that the salads it ships are not only delicious but also safe and long-lasting, Ontario, California-based FiveStar Gourmet Foods begins its production process by selecting only the highest-quality ingredients at the peak of freshness, says Tal Shoshan, the company’s CEO.

FiveStar, the nation’s largest producer of single-serve salads, can produce more than 1,200 salads per minute. And when it moves into its new state-of-the-art facility later this year, FiveStar will triple its production capabilities.

After choosing only the best lettuces from California’s Central Coast, FiveStar then ensures that the lettuces meet the most stringent water treatment practices and food safety protocols. Once the lettuces, toppings, dressings and other ingredients are assembled by hand in the company’s patented salad bowls, the bowls pass through a modified atmosphere packaging process to ensure the freshness holds up and looks great even after 12 days, Shoshan says.

A robust logistics system guarantees that FiveStar salads are shipped quickly to its retailer partners throughout the U.S.

“The process of salad making continues to evolve, but ultimately it’s about creating a premium salad that looks amazing, tastes like you purchased it at a restaurant and is also affordable,” Shoshan says. “FiveStar continues to pair the latest technology with the most highly trained workforce. We need the help of machines to meet efficiency, but we absolutely don’t want our salads looking like they were made by machines. It’s a balancing act.”

Food safety is FiveStar’s top concern, Shoshan says. The company uses x-ray inspection and other cutting-edge food safety technologies and is one of a few fresh-cut companies to employ “test and hold” protocols to ensure that products are safe and wholesome before they’re shipped.

FiveStar is also one of the only processors that uses sophisticated DNA testing to detect pathogens quickly. The entire food safety and quality system is audited by third party auditing firms, and FiveStar has earned SQF-Level 3 certification, the highest rating possible, at all of its facilities.

All FiveStar employees are fully trained over many hours for food safety and food quality, Shoshan says. Team members must pass GMP and food safety training prior to being able to work for the company. Line leads, supervisors and QA personal constantly monitor the production lines to ensure strict adherence to product specifications, and visual photo breakdown of each step is always available to employees.

Employees are rewarded for reporting any issues and concerns, and the company encourages and fosters team collaboration and respectful communications. Every month the team selects the MVP of the month based on criteria that encourages FiveStar excellence. 

 “Consumers and retailers put their trust in us, and we take this very seriously,” Shoshan says. “Our production process is all about attention to detail. Our team members are trained to treat each and every salad bowl with the utmost care and pride. State-of-the-art facilities and the latest technology are simply good tools that are secondary to our team members.”