Site Planning
Installation & Commissioning
Automatic & High-efficiency
Client Name： O****N Onion Growers Cooperative
Country： United States of America
Region： Border of Idaho & Washington – the world's largest onion production base, famous for sweet onions
Core Products： Dehydrated onion slices, frozen onion dices, ready-to-eat salad onion slices, pre-cut onion ingredients for catering
Equipment Configuration： Hadof customized high-speed onion slicing production line (including automatic washing & grading system, precision thickness slicing unit, online anti-atomization and IQF freezing/drying connection module)
Commissioning Time： Q2 2021
The United States is a major onion producer. The sweet onions produced in the border area of Idaho and Washington are famous for their large size, sweet taste and uniform layers, supplying the North American and Asia-Pacific markets all year round. O****N Group is the largest onion growing and processing cooperative in the region, with more than 80 years of history in onion planting and primary processing. With the increasing requirements for onion slice specifications and quality in the catering chain, ready-to-eat salad and dehydrated vegetable markets, the traditional manual slicing method can no longer meet modern processing needs.
Core challenges in onion slicing:
Irritant gas affects health: Onions release sulfur compounds when cut, resulting in high concentration of irritant gas in manual slicing environment, causing workers' tearing, coughing and eye discomfort, leading to high labor turnover and difficulty in recruiting skilled workers.
Prominent capacity bottleneck: More than 60 tons of onions need to be processed every day in peak season, and manual slicing requires more than 300 workers in shifts, which still cannot meet order demand, with delivery cycle up to 45 days.
Poor slicing uniformity: Manual slicing thickness error reaches ±2mm, resulting in inconsistent drying time and uneven color of onion slices in dehydrated or frozen products, with a rejection rate of up to 10% for high-end customers.
Serious raw material waste: Scraps and leftovers caused by irregular slicing account for more than 12%, high-quality onion resources are not fully utilized, and profit margins are greatly compressed.
Hygiene and foreign body risks: Many manual contact links make it difficult to control microorganisms and foreign bodies, which is difficult to meet the strict requirements of ready-to-eat vegetables in North American and EU markets.
According to the characteristics of distinct layers, high water content and strong irritation of onions, Hadof team customized a fully automatic onion slicing production line for O****N Group:
1. Automatic Washing, Grading and Directional Conveying System
The front-end is equipped with a drum washer to effectively remove sediment and outer skin. Through the visual grading system, onions are divided into three grades: large, medium and small according to diameter, and sent to slicing channels of corresponding specifications. The directional conveying device ensures that onions enter the slicing station in the best posture to improve slicing uniformity.
2. High-precision Closed Slicing Unit
The whole machine adopts fully closed design, equipped with negative pressure air extraction system to collect and treat irritant gases centrally, significantly improving the workshop environment. The blade is made of corrosion-resistant stainless steel circular knife, with thickness adjustment range of 2mm-12mm and deviation controlled within ±0.3mm, meeting the needs of different products such as dehydrated slices, frozen dices and salad slices. The blade surface is treated with Teflon anti-stick coating to prevent onion juice from sticking, and no cleaning is required for 8 hours of continuous operation.
3. Online Anti-atomization and Rapid Cooling System
After slicing, it immediately enters the low-temperature air purging area to quickly reduce the surface temperature of slices, reduce juice loss, and inhibit enzymatic browning. Qualified slices are screened by vibration, automatically separating scraps and complete slices. Scraps are recycled as dehydrated raw materials to realize comprehensive resource utilization.
4. Intelligent Color Sorting and Metal Detection
Equipped with high-speed visual color sorting system, it automatically identifies and removes browning slices, insect-infested slices and foreign bodies, with sorting accuracy of more than 99.5%. The back-end metal detector ensures product safety and meets North American and EU market standards.
5. Hygienic Design and Easy-to-clean Structure
The whole line adopts 304 stainless steel fully closed structure, all contact surfaces are designed with rounded corners, no sanitary dead corners, supporting CIP in-situ cleaning. Key components can be quickly disassembled to meet the highest requirements of ready-to-eat vegetable processing in BRC and IFS international food standards.
Client Testimonial: From Traditional Manual Work to North American Onion Processing Benchmark
Since the full operation of the new line in 2021, O****N Group has achieved leapfrog development:
Capacity and Efficiency
Daily fresh onion processing capacity: increased from less than 20 tons of manual processing to 60 tons per shift, with full capacity up to 95 tons/day, becoming the largest onion slicing processing base in western North America.
Labor optimization: The number of workers in the slicing section has been reduced from 300 to 18 technicians, labor costs reduced by more than 90%, completely solving the problems of difficult recruitment and workers' health.
Quality and Market
Finished product qualification rate: slicing thickness consistency reaches more than 99%, scrap rate reduced to less than 3%, product appearance is regular, North American and European customer rejection rate reduced from 10% to less than 0.6%.
Market expansion: Passed BRC, IFS and organic certification, successfully entered the supply chain of large North American catering chains (such as McDonald's, Subway) and supermarkets (such as Walmart, Costco). The proportion of deep-processed product export revenue in the group's total revenue increased from 15% to 55%.
Comprehensive Benefits
Raw material utilization rate: Through precise grading slicing and intelligent sorting, the comprehensive raw material utilization rate increased from 84% to 96%, saving more than 500,000 US dollars in annual onion raw material costs.
Energy consumption optimization: The whole line adopts high-efficiency variable frequency motors and waste heat recovery system, unit output power consumption reduced by 22% compared with traditional split equipment, won the US Department of Agriculture Green Manufacturing Special Award.
"Hadof's onion slicing line has completely bid farewell to our 'teary processing workshop'. Now, every onion slice enters the tables of North American consumers with precise thickness and clean quality, and our workers work in a comfortable environment for the first time. This is an investment that wins both employee health and enterprise competitiveness."
—— O****N Onion Growers Cooperative, Operations Director Mr. Johnson
