The global demand for frozen food has continued to grow as it has been for the past decade, driven by increasing demand for convenience with consumers looking for healthy, but less time-consuming meals.
The meat segment has accounted for the highest share of the frozen food market segment followed by frozen ready meals and pizza. However, frozen fish/seafood, fruit and vegetables, bakery and desserts, and potato products have also contributed to the growth.
According to the forecast by market research firm TechNavio, the global cold chain market had a revenue of US$75 billion in 2011 and is expected to reach US$157 billion by 2017 at a CAGR of 13.2 percent. Asia Pacific is set to be the fastest growing region with a CAGR of 17 percent.
In the face of this continually rising global demand for frozen food products, the need for a more reliable and efficient deep-freeze supply chain has become a challenge to overcome.
An unbroken deep-freeze supply chain is an uninterrupted series of storage and distribution activities which maintain frozen products at a consistent sub-zero temperature range. Consequently, deepfreeze warehousing has become a focal point for food processors, distribution centres and retailers to streamline throughput and improve cost efficiencies.
Deep Freeze Challenges
The first cold chain challenge that companies face is the maintenance of high product quality under sub-zero temperature. Across the entire supply chain, from the food manufacturers, wholesale distribution centres, multiple retailer distribution centres to retailers, products must be kept at a deep freeze temperature of -28 deg C.
In order to comply with cold chain regulations, products can only be exposed to up to +18 deg C for a maximum duration of 20 minutes and +4 deg C for a maximum duration of 30 minutes during storage and transportation. In addition, tracking and temperature history records must be maintained for reference purposes.
The second challenge is that of speed. Every aspect of sub-zero warehousing is moving faster. The consumption of frozen products has increased dramatically and rapid replenishment of retailers’ shelves is important in order to not lose any sales in stores.
As a result, companies have to facilitate faster receiving and dispatch of goods. In order to stay competitive, food products, distribution centres and retailers need to implement systems for deep-freeze that will have the flexibility to adjust to market conditions such as increases in SKU range and shortened lead times very quickly and accurately.
Deep-freeze facilities need to acquire the same standards of storage and picking methods used successfully in the chilled and dry grocery product sectors. They require systems that will respond to retailer needs and get products out of the deep-freeze warehouse to retail outlets quickly and with minimal order errors.
Today, producers, distributors and retailers of frozen food products need to track and identify where each pallet came from, where it was stored, what the temperature was in storage, and other critical data to keep track of its perishable inventory and ensure its product integrity.
Manual handling leaves open the possibility of human error, but streamlined programmable logic controller (PLC)-controlled automation, integrated with a warehouse management system (WMS), provides this data quickly with reliable and verifiable documentation.
Extreme Working Conditions
The third challenge is ensuring operational efficiency in extreme environment with difficult working conditions. Compared to non-deep-freeze facilities, most manually-operated sub-zero warehouses have a higher incidence of product damage, missed product rotation and wrong item fulfilment which have negative impacts on order fulfilment.
These warehouses also have heightened facility, equipment and product damage, primarily caused by manually-operated fork lifts impacting racks and doors, significantly higher than that found in ambient temperature and chilled warehouses.
Not surprisingly, personnel turnover in sub-zero storage facilities is also higher than in non-deep-freeze warehouses. Whilst the temperature in these facilities is cold enough to store food products safely, it creates an extreme environment with difficult working conditions for personnel, increased safety issues, and staff recruitment and retention problems.
Automation of deep-freeze warehousing has been embraced as an ideal solution to these difficulties. The most streamlined frozen food warehouses today are highly automated sites, with maximised high-bay, high-density storage utilising automatic storage and retrieval system (ASRS).
These deep-freeze warehouses maintain precision product identification and rotation, provide rapid throughput at over 99.9 percent accuracy levels, and are considerably more energy efficient than their manually operated predecessors.
Switching To Automated Systems
There are major benefits for warehouses to switch from a manual to an automated deep-freeze facility: maximised building volume utilisation and increased cost efficiency through high-bay accessibility. In a typical manually-operated sub-zero warehouse, forklift trucks are limited to a maximum reach of around 12 m, allowing for pallets to be placed into four vertical positions on the rack system.
If a deep-freeze needs to store more pallets, the only way it can go is horizontally by expanding the footprint of the warehouse or building another deep-freeze to accommodate the additional pallet locations. It is not unusual for food manufacturers to have multiple manual deep-freeze locations, continuing to add storage footprint as the company expands. Within a high-bay warehouse system, it is possible to have as many as 20 vertical pallet positions on racks 40 m high. For the deep-freeze warehouse environment this is an important efficiency factor in footprint consolidation.
It can handle the same number of pallets, but on a smaller footprint. Footprint reduction becomes an increasingly important factor in energy savings since much of the cold loss in a sub-zero warehouse occurs through the roof.
In effect, deep-freeze warehouses are giant insulated freezers which extract heat to produce a cold environment. The removal of heat comes at a hefty energy cost. Having a smaller roof footprint in a sub-zero warehouse presents a considerably better energy solution.
Typically, 43 percent of the refrigeration load in a deep-freeze is due to losses through the roof and walls. For example, high-bay deep-freezes, on average, have 40 percent less surface area than warehouses using lift trucks. A 2,000 sq m high-bay deep-freeze facility with 10,000 pallet locations could reduce energy costs by up to one-third of that needed for a manual facility handling the same number of pallet locations.
Those high-bay, deep-freeze warehouses that are the most energy and cost efficient have achieved a high density of space utilisation. This means they have a space configuration that allows for the maximum number of pallet positions to fi t into the facility.
High-bay systems optimise cubic space usage in deepfreeze, not only by their vertical stacking capability, but also by minimising aisle cubic footage.
By eliminating the need for forklift trucks, aisles can be made significantly narrower—allowing 3.7 m wide aisles to become just 1.5 m wide. This space can then be used for more pallet positions.
Aside from maximising the cubic space utilisation of the physical deep-freeze structure itself, it is the automated equipment inside that defines the warehouse’s throughput speed and efficiency. However, designing systems that will function optimally under these extreme conditions requires careful engineering.
Not all automated warehouse equipment performs well at -28 deg C. The most high-speed and durable material handling equipment capable of a high level performance at ambient temperatures would in short time be incapacitated in a deep-freeze environment.
Specially blended steels, oils, greases and other lubricants for gearboxes, bearings and drives are specified for extreme low temperatures. Wiring and electrical cables are designed to flex in these temperatures. PLCs, PCs and other electronic controls components are kept in heated cabinets.
Photo-electronic sensors that feed computer information and detect pallets are maintained to be free from frost by being equipped with heating devices.
Automated systems for deep-freeze need to be designed to include these features, not only so that they can be highly streamlined, but also for system longevity. Such equipment encompasses a range of fully-automatic and semi-automatic options, including ASRS for mini loads, robotic picking systems for cases, and modular conveying systems for pallets and unit loads.
ASRS is a fully automatic system for deposit, storing and retrieving unit loads from defined storage locations. They allow inventory to be moved quickly, safely and precisely in a warehouse environment.
When applied to a sub-zero warehouse, ASRS produce dramatic results, effectively making a deep freeze facility as efficient as an automated ambient or chilled warehouse.
The latest generation of ASRS provides a uniquely flexible and modular design that is equipped with a multi-load remote pallet handling capability, ideal for deep-freeze warehouse automation at its coldest (-28 deg C).
These ASRS allow rapid configuration to the right storage and retrieval need for almost any application. From floor level to up to 40 m (131 feet) tall, they provide single-deep, double-deep, triple-deep and multi-deep storage configuration, with the flexibility to handle one and multi-loads at a time.
High-bay deep-freeze warehouses are ideal candidates for the precise and efficient tracking of frozen food products because of their highly automated and computer-controlled systems.
The warehouses’ WMS, along with PLCs in the ASRS and modular conveying system, are capable of monitoring pallet moving, production dates and weight as the unit loads and cases are moved through and stored in the facility.