5 replies to this topic

[Milos Vasic]

Hello
Could anyone help me in decision about future line for grain cleaning and sorting. We are planing to buy equipment for cleaning, sorting, grading of products like brown rice, flax seed, sesame seeds, sunflower kernels,pumpkin seeds etc. When we discussed material of which parts that are in contact with material will be producer told us that we can choose between
simple(black)steel,
galvanized
and stainless.
From their experience very few customers asked for much expensive stainless steel. Since products passing are just dried grains only cleaning item is dust, so washing of equipment is not done frequently. Metal parts which are in contact are sieves, small silo, feeding hoppers They also told us that also from their experience although machines are not from stainless steel customers have HACCP certificate.

[DP2006]

Hi Milos,

Leaving aside the question of materials of construction ie simple(black)steel, galvanized and stainless what are you planning to do in terms of metal detection and removal?

The location of magnets, sieves and metal detection (appropriate) with formalised quality systems for cleaning, recording and calibration (metal detection) are also important factors.

Routine inspection of the equipment for rust, damage etc is also an important factor. This should be on an agreed frequency and part of a formalised quality system.

Although some customers might "demand" use of stainless steel this might not be practical or cost too much. On this basis the other quality systems are more important eg magnets etc.

Good luck.
DP2006

[sarahfoodtech]

Hello,

I agree with DP2006, you need to consider what preventative measures you have for metal contamination. I have worked in HACCP for the grain industry in Canada, and some of our equipment was almost 100 years old!

One thing you really need to keep in mind is the end use of YOUR product. To me you are describing a cleaning, sizing , sorting operation. From the details you mentioned I am guessing that you load trucks, totes, or railcars with your end product to send to customers for further processing.

Metal detection, magnets, and sieves do not necessarily need to be considered a CCP for your operation if your end product does not get sold directly to the general public. If this is the case you just need to address metal contamination in your operation and how it could affect your customer (ie, possbile large metal fragments could damage their processing equipment).

Basically if the assumptions I have made on your process are correct you need to balance the cost factor of the materials and the life span of each metal product to suit your operation, as all the materials you listed are ok for the grain industry.

[MRios]

Like Sarahfoodtech said, many of the older mills work with equipment that is close to a century old, when stainless steel was not used. You will only be doing "dry" cleaning and because your operation will be dedicated to cleaning and sorting grains, these should have a low moisture just to make sure they won´t decompose. This reduces the risk of rust.
Most equipment that cleans and sorts includes some sort of airflow to get rid of fine particles or even just to move the product along, plus magnets to trap any ferrous metal. The machines themselves use sieves to sort the grain or seeds, so that also helps them to get rid of large contaminants.
From what I´ve seen, the passing of grain or seeds could slowly deteriorate certain parts of the tubing, but in that case, there´s more risk of having a hole through which the product would leak. The particles resulting from the erosion of the tubing are too small to be of any danger.
So go with the best alternative in terms of price and durability.

[Charles.C]

Dear All,

The (general) feeling of this thread appears to be that price is a higher priority parameter for equipment decision making compared to safety (ie food / process grade stainless-steel). I suggest this concept needs to be treated with some care and on a case-by-case basis.

It is undeniable that non-Stainless Steel options, eg galvanised (and some indeed antique), can be seen in every industry. Even IMEX at the front end of high-value RTE products (though perhaps depending on brand?) and sometimes at the back-end also.

And many of these systems do perform admirably, especially where corrosion is not a factor, the galvanised / etc quality is good, and particularly IMEX where the equipment is new.

However I hv also met various examples of the opposite case where frequent repainting of second-hand equipment has to be done in order to mask an (acknowledged) risk of metal contamination. The justification for continued use is invariably one or a combination of 2 criteria, (a) existence of {first) processor “catching” stages which validatably trap any disintegrated particles or coupled with (b) documentation certifying that the receiver (secondary procesor) will screen all incoming material for metal particles. Without such “back-ups” I would personally find it impossible to approve such set-ups.

I suspect the pragmatic situation is that many industries have self-created their own standard due lack of any over-riding control to the opposite. In contrast, one can only admire the luxurious magazine pictures of automated, stainless-steel, conveyored systems for making things like pizzas and chocolates etc.

My opinion is I fear the obvious one, for start-up, if you hv the money, go stainless unless yr particular situation cannot (short/long term) safety-wise justify it. Does the latter exist ?

Rgds / Charles.C

[Milos Vasic]

Thank you all for the answers.
I see that topic has moved into direction that I did not have in mind. To answer all, yes we will have metal detector and color sorter at the end of the line. Line will have pre cleaning, stone separation, (optional shelling), grading, gravity separation,color sorting, metal detection, packaging .Products like rice, hulled sunflower, sesame seeds, flax seeds etc will be packaged into 5-25kg bags, sold to the bakeries, confectionery producers and healthy food retailers, so we need to have metal detection as CCP. Transport will be done with bucket elevators and air transport. For the air transport we will see that knees are made of stainless steel.

When I posted topic what I had in mind was microbial and chemical risks in this type of processing due to the fact that equipment cannot be washed (so easily) if its not made of stainless steel. In fact only reason to think about stainless steel is just because of washing since I don't see that there will be places where we will have some intense product and surface contact that would need stronger steel than regular.