By Lindsey Klingele on 9/30/2013

http://www.meatingplace.com/

Knives and blades are among the most basic and yet most important tools in a meat processor’s arsenal. They include dicing blades, skinning blades, boning knives, circular knives, straight knives and hand knives.

Though the basic function of these knives – to cut, chop, slice and dice – hasn’t changed, some technology surrounding them has. Next-generation grinding technologies and steel blends keep knives sharp and prevent loss of yield, while new ergonomic grips help to prevent worker injury and keep down costs

New knife grinding technology

In a meat plant, keeping knives sharp is a necessity to prevent both worker injury and loss of yield. Dull knives can lead to tearing, mis-cuts and waste. Workers also have to apply more pressure when cutting with dull knives, which can increase strain and lead to injury. According to scientific journal Applied Ergonomics, using a sharp knife over a dull one can increase processing speed by 1.5 times and increase yield by 1.2 percent.

Advances in grinding technology can help processors determine when a knife has become too dull to make successful cuts. Knife sharpness analyzers take several measurements from a blade’s edge to determine whether or not it needs to be sharpened. Some next-generation grinders also utilize technology that informs users about the condition of a knife before the grinding process commences.

Many grinders on the market allow users to manually adjust settings for each knife that needs to be sharpened. However, some new grinding systems use PC technology that stores settings for different types of knives on a hard drive. To reduce set-up times, users can simply utilize a control panel to bring up the settings that correspond to the size and shape of a particular knife. The machine then moves the knife to its grinding device, where it grinds it according to the program selected.

The difference is in the steel

Two of the main types of knives used in the food industry include those made of carbon steel and those made of alloy steel, such as a stainless steel. Each type has different advantages.

When carbon is added to steel, it hardens the material and makes knives more resistant to rust and wear. High-quality carbon steel knives are typically stronger than stainless steel knives and can be easier to sharpen.

Stainless steel knives are made with chromium and nickel. The chromium makes the steel tough and resistant to scratches and rust. Nickel adds toughness and elasticity, which helps knives to keep their shape. While carbon steel knives might be easier to resharpen than their stainless steel counterparts, advocates of stainless steel claim that these knives can maintain sharpness for longer periods of time. However, inexpensive, low-carbon stainless steel blends can lose an edge faster than both quality carbon steel and high-carbon stainless steel blades.

Manufacturers have added other alloys to steel to provide various benefits. A carbide former such as vanadium can refine the grain when it is added to steel. These knives can also take on a keen edge but can be more difficult to sharpen. Another carbide former, tungsten, can help steel to withstand heat and therefore survive more grinding processes. It also makes steel more resistant to shock.

The SAE steel grades system assigns numbers to different types of steels, starting with type 100 and moving upward. Though many knife manufacturers use proprietary steel blends, a number of knives made for the food industry are similar to the 400 series, specifically 440a steel. Type 440a is one of the hardest stainless steels, and it is good for wear resistance.

Specific blade finishes can also produce different results in cutting meat. Research published in Applied Ergonomics found that blades sharpened to a fine polish finish can reduce cutting time by 25.3 percent when compared to blades with a coarser finish. They can also reduce the amount of force used to grip the blade handle during cutting by 21.2 percent.

Ergonomics and knives

Working with knives can obviously lead to the occasional slip and cut. However, other injuries associated with repetitive knife use include cumulative trauma disorders (CTDs) and musculoskeletal disorders (MSDs). Using knives with ergonomically designed handles can prevent worker compensation claims and lost days that might cost the meat industry billions cumulatively, according to the U.S. Bureau of Labor Statistics.

Ergonomic knives feature handles with a hard core but a soft exterior. They allow workers to grip and hold the knife with relative comfort. Often, different knives are specifically designed to allow for different repetitive activities, such as slicing or chopping. Handles should also be slip-proof so they don’t slide out of workers’ hands when they become greasy or wet.