Nuts are one of the most popular snacks around the world, and they come in many different varieties. Peanuts, cashews, pistachios, almonds, walnuts… the list goes on. They’re also an important ingredient in many recipes, both savory and sweet.
The global nuts and seeds industry is worth $1301.4 billion, according to Statista; by 2023, this number will reach over $1.420 billion. Between 2020 and 2021, over 5.3 million metric tons of tree nuts were produced worldwide. The top three nut types by production volume are almonds, walnuts, and cashews.
With the global nuts and seeds industry growing rapidly, so is the demand for efficient nut conveying solutions that can handle large volumes without damaging the product.
In this blog post, we will explore the main challenges of conveying nuts in food processing and how to overcome them.
Nut characteristics
Like with conveying any other type of material, the challenges that come with nut conveying are largely due to the product’s characteristics.
Nuts and nut “meats” are typically dry, hard, and have a high oil content. They come in a variety of shapes and sizes, which can make them difficult to convey without breaking or damaging them. The average bulk density of most tree nuts is between 30 and 35 lb/ft3.
When in the whole form, nuts are typically free-flowing, meaning they don’t require flow promotion devices to pass through conveying equipment.
However, once they’re sliced or ground, they can become more difficult to convey. The high oil content in nuts can also leave residue on the conveyor, allowing for easy product contamination and increased food safety risks if not cleaned properly.
Due to all of these characteristics, nuts need to be gently transported using relatively low speeds to prevent breakage.
Let’s explore nut conveying problems in more detail and see how they can be solved.
Most common nut conveying challenges
The challenges most frequently encountered when conveying nuts can be divided into three main categories: product breakage, product contamination, and the release of dust into the facility.
Material breakage and waste
According to Cablevey’s detailed study on the current state of conveying, about 30% of food processing facilities cite broken materials as their number one conveying challenge; this is especially true for food processors that handle nuts.
Nuts are dry and hard, which makes them susceptible to breakage when conveyed at high speeds. These fragile ingredients can also be damaged by abrasion from contact with other materials or by being dropped from a height.
Preserving the shape and texture of each nut is paramount for the success of the final product. Even a 1% reduction in whole, unbroken nuts can result in a significant decrease in product quality, thus resulting in financial losses.
Material contamination and cross-contamination
In material handling, contamination is defined as the presence of foreign matter in the conveyed material.
This can be due to physical contaminants (e.g., metal shards, glass, or stones), chemical contaminants (e.g., cleaning chemicals or oils), or biological contaminants (e.g., bacteria, mold, or viruses). All of these types of contamination can have disastrous consequences for the final product.
Cross-contamination is a specific type of contamination that occurs when conveyed materials come into contact with other materials that are not part of the final product. This typically happens when products are conveyed on a shared conveyor belt or in an environment where there is a risk of product spillage.
The potential for contamination exists in pretty much any food processing facility. Since nuts are high in oil content, they can leave residue on the conveyor belt, which creates a perfect environment for bacteria to grow. If not cleaned properly between load changeovers, the oil residue can lead to cross-contamination of other products.
Both contamination and cross-contamination can lead to recalls, product wastage, and damage to a company’s reputation.
In 2003 and 2004, a Salmonella outbreak in North America was traced back to contaminated raw almonds. The outbreak resulted in 29 people falling ill across the United States and Canada, 7 of which had to be hospitalized. The almond producer had to recall approximately 13 million pounds of raw almonds as a result.
Based on the above example, it is crucial to take measures to prevent contamination from happening in the first place.
Dust
During food processing and transporting food ingredients and products, a certain amount of dust is generated. This dust typically comes from the product itself, especially if it gets damaged during conveying.
While a small amount of dust is to be expected in any production process, too much dust in the air can create problems for both workers and equipment. Inhalation of large amounts of dust can cause respiratory issues, while a build-up of dust on surfaces can lead to fires or explosions.
When conveying nuts, especially if they are broken or ground, it is far too easy for dust to be generated and become airborne. This can create a hazard for workers in the vicinity and contaminate other products.
How to overcome nut conveying challenges
All of the challenges we’ve described above can be effectively solved by using the right conveying system.
Here are the main features a nut conveyor system must have in order to keep your production line running smoothly:
Low conveying speeds
All fragile goods, including nuts, should be conveyed at relatively low speeds to minimize the risk of breakage.
A good rule of thumb is never to exceed the recommended maximum conveying speed for the product you’re handling. If you’re not sure what that speed is, consult with the manufacturer of the conveying system or a qualified engineer. In most cases, conveying at a lower rate will not significantly impact the overall production time, especially if the conveying system is designed correctly.
Gentle material handling
The way your system transports these delicate ingredients is also crucial. Nuts should never be dropped or thrown, as this increases the risk of breakage. Instead, they should be gently lifted and carried to their destination with as minimal movement as possible.
This can be achieved by using a system – such as a tubular cable and disc conveyor – that doesn’t allow the conveyed materials to bounce around. Such a system is also less likely to damage the product in case of a power failure or unexpected stop.
Easy cleaning systems
To ensure that there is no product contamination, the conveying system must be easy to clean. All surfaces that come into contact with the product should be smooth and free of cracks or crevices where bacteria can hide.
The system should also be designed in a way that allows all parts to be taken apart and cleaned easily. If possible, choose a system that doesn’t require the use of tools for disassembly or one that has clean-in-place (CIP) mechanisms.
Cablevey conveyors have just such wet and dry cleaning options available. Our CIP options make it easy to clean the system without any significant disassembling required. And the ability to inspect the interior of your systems using our Internal Mini Camera.
Of course, your cleaning protocols should also include regular cleaning of the facility itself as well as all workers following good hygiene practices.
Enclosed structures
Another important aspect of preventing product contamination is to keep the conveyed materials enclosed as much as possible. This minimizes the amount of dust that gets released into the air and also protects the product from external contaminants.
Cablevey tubular drag conveyors transport the product through a series of fully-enclosed tubes. These tubes are connected with special joints that create an airtight seal. The result is a working environment that is virtually dust-free, and that ensures almost non-existent material loss.
Conclusion
Conveying nuts can be a challenge. Food processing facilities need to take into account the potential for product breakage and contamination, as well as the need for easy cleaning.
The solution to all of these issues is finding a conveying system that meets the specific needs of your facility.
Tubular drag conveyors are an ideal solution for nut conveying applications. They transport the product gently and at low speeds to minimize breakage. The enclosed tubes also keep dust and contaminants out, while the CIP option ensures easy cleaning between production runs.
Cablevey Conveyors is a world-leading provider of gentle tubular drag conveyor systems. Our conveyors are custom-designed to meet the specific needs of your organization, so you can be sure you’re getting the right system for the job.
If you’re looking for a reliable and efficient nut conveying solution, contact Cablevey today. We’ll be happy to discuss your goals and help you find the perfect system for your facility.