Potatoes are not only used as a vegetable for consumption at home but also at restaurants. Global consumption of potato as a food item has seen a shift from fresh potatoes to value-added products. It is estimated that a little less than 50 percent of potatoes grown worldwide are consumed fresh. The remaining are processed into potato food products and food ingredients like animal feed, processed into starch for industry, and re-used as seed for growing next season’s potato crop.
The market of Potato Powder and Flakes is increasing at a rate of 4.52% each year. In 2015, Italy, United Kingdom and France imported 134 million dollar’s Potato Powder and Flakes out of 616 million dollar trade in the same year. In 2015, Pakistan imported 2,764 tons of Potato Powder and Flakes worth 3.78 million dollars in the same year.
Pakistan has abundance of unprocessed potatoes, especially in Punjab province. However, many companies in Pakistan and China are importing potato powder to meet their demand due of lack of potato processing units. The proposed unit having capacity to produce 1,728 tons of Potato Powder a year based on 180 processing days, can meet the local demand and enter into global market for export.
Uses of Potato Powder in Pakistan
Potato Powder is a dehydrated vegetable made from the whole potato which absorbs large amount of water. The manufacture of potato powder is based on the efficient dehydration of peeled cooked potatoes on single drum dryer. The thin dried sheet of potato solids is then ground to the desired fineness. As a dehydrated vegetable, Potato Powder can be used in a wide variety of industries including: food production, beverage, agriculture / animal feed, and various other industries. It can be used as:
- Nutritional supplement in food production
- Bread improver in baking
- Breading for fried foods; frozen fried chicken and seafood products
- Thickening agent; used in soup mixes sauces and baby foods
- Base material for many snack foods including potato-chip like fried products
- Ingredient formula in making pharmaceutical and cosmetic products
- Nutritional supplement in Agriculture / Animal Feed
Potato dehydrated products are lightweight, easy to transport and require less storage space. “Lady Rosetta, Chipsona, Hermes and Pamela” have proven to be successful varieties as raw material and meet global requirements. It should be noted that these varieties are available and grown in Pakistan. Dry matter levels higher than 20% are ideal for processing flakes and powder and produce increased recovery rates and lower overall production cost. Maximum shelf-life of properly dehydrated and packed products is around 18-24 months.
The by-products of this process i.e. peel and cutting losses can be sold to cattle farmers or compost producers to generate additional revenue and off set the input cost of raw material.
Production Process of Potato Powder in Pakistan
Production process of potato powder is given below in detail:
Washing & De-stoning
The process starts from intake of raw potatoes. The raw potatoes come via a belt conveyor into the rod de-soiler of the washing plant. The potatoes then arrive into the cyclone de-stoner, where an upward stream makes the potatoes float, while heavy parts such as stones and clods sink. A special stone conveyor seizes these separated heavy parts, lifts them out of the water and drops them in a container.
A flume transports the product with circulation water in a washing machine with two compartments.
- Separation of circulation water
In the first compartment, the potatoes are separated from circulation water. The potatoes then enter the washing compartment, where a bar-type drum immersing 10 to 15 cm into a water bath with its special internal components thoroughly moves and rubs the potatoes so that even loam comes off easily. The potatoes are then sprayed with water. The washed potatoes are transferred into a hopper for intermediate storage.
Friction peeler is a dedicated machine to remove the skin of potato, potatoes move up and down in the barrel, which produces relative movement of friction, so as to achieve friction peeled effect. A screw conveyor serves to reclaim the product, evens it and feeds it into the dry de-skinner. In the front part of the Skinner, thorough and suitable surfaced rolls remove the loose potato skin. A pump discharges the mushy skin, which is used as high quality animal feed.
A screw conveyor serves to deliver the potatoes through the machine, the speed of which (and consequently the retention time) is variable. A downstream washing machine washes skin residues and dissolved potato cells off the potato surface. From the washer, the peeled and washed potatoes get onto an inspection belt conveyor, where they are sorted by hand and, if necessary, trimmed. Rejected potatoes get into separate containers and are also used as animal feed.
Slicing, Blanching & Cooling
An inspection belt conveyor transfers and feeds the peeled potatoes through a distributor into the slicing machines. Here the potatoes are cut into slices to allow easy transfer of heat during the pre-cooking process. The thickness of the cut can be adjusted according to the requirements. Then the potatoes are pre-cooked in a warm water bath. The pre-cooker is of a steam injection screw type. This is called blanching and it is carried out in order to achieve the following:
- Helping in gentle gelatinization of the starch (Starch gelatinization is a process of breaking down the inter-molecular bonds of starch molecules in the presence of water and heat, allowing the hydrogen bonding sites (the hydroxyl hydrogen and oxygen) to engage more water. This irreversibly dissolves the starch granule in water), without impairing the cell membranes as a result of the large volume.
- Changing the inter-cellular cementing substance in such a way that the cells separate more easily after cooking.
- Preventing the enzymatic discoloration of the product.
A lifting wheel separates the potatoes from the pre-cooking water and feeds them through a flume into a screw-type cooler, where they are cooled in a water bath. The result of this is the retro-gradation of the starch gelatinized in the precooking stage. Retro-gradation in turn reduces the amylose solubility. Starch retro-gradation is desirable for starchy food products in terms of textural and nutritional properties.
The product is discharged from the wet hopper via a water lock and transferred hydraulically. A vibrating screen separates the potato slices from the conveying water, which flows back through an equalization tank into the hopper. A balance provided in the downstream belt conveyor measures the mass flow rate, which is set by varying the speed of the product feeder. Via a final lock, the belt conveyor feeds the product into a screw type cooker, where it is cooked at atmospheric pressure in steam or vapor.
The cooker used is a screw type unit, injecting steam just above the machine bottom and the screw shaft to provide a uniform temperature in the product and consequently homogeneous cooking. Efficient removal of condensate makes sure that the water content of the cooked product only increases just slightly. The optimum cooking time must be determined empirically and will have been reached when the cell-cementing substances have been weakened to such a degree that the cells separate with no major destruction of their membranes.
Grinding / Mixing
After mashing and drying. The grinder unit will crush the dried potato layers into powder form and also the feeder system will add dried potato material (addback) from granules which will process the cell bondage and provides for homogenization of both materials. Necessary additives are also fed into the mixer during the mixing process.
Three Step Drying
Drying (Air-Lift Dryer): The drying air is heated by a steam heat exchanger with high pressure steam to obtain the necessary drying temperature. The mixed product enters the drier at right angles to the air flow. Subsequent deceleration and multiple diversion of the product stream leads to frequent high relative movements between the particles and the hot air, resulting in optimum utilization of energy and an optimum drying efficiency. Centrifugal-force cyclones separate the dried product and discharge the exhaust air into the open.
Drying (Fluidized-Bed Dryer / Cooler): The separated product from the cyclones is conveyed to the second dryer. In the unit fluidized product bed develops above a distributor plate. This is a perforated plate which produces an even inclined air stream. This makes the fluidized bed move almost in a linear way, and the thickness of the bed determines the specific residence time of the product. The fluidized-bed unit consists of two zones:
Drying zone: An appropriate part of the in going air is heated by a steam heater and then is blown by a fan into the drying zone.
Cooling zone: Another fan feeds cooling air into the cooling zone. The temperature of cooling air is the same as outside temperature.
Final Dryer (3rd Drying): The drying and cooling air is blown by separate fans through a perforated plate into the drying and cooling zone. The fluidized product bed develops above the perforated plate. An appropriate part of the in going air is heated by a steam heater. The temperature of cooling air is the same as outside temperature.
The product is bagged into PE-lined multi-layer paper bags. Package weight: 25 kg bagging, bag closing and palletizing are manual processes.
Factors for Success of Potato Powder Manufacturing in Pakistan
Following principles need to be pursued for the best productivity of Potato Powder:
- Prices of Potatoes are volatile, so due care and diligence should be taken while procuring fresh potatoes. An experienced procurement officer having good knowledge and understanding of potatoes quality and price fluctuation should be permanently hired for the facility.
- Higher recovery ratio of powder is from fresh potatoes while stored potatoes give lower recovery ratio.
- Potatoes with high solid contents and low sugar are best to produce dehydrated products. These types of potatoes are widely available in Pakistan.
- Quality raw (potato) material and adaptive research & development is necessary for the project.
- Storage management and quality improvement is needed.
- Policy intervention and government support is required.
- Enhance the skill of the contract farmers, the process relevant staff and management should be ensured.
- Capacity building of the farmers, company staff and the management are lacking as this is a newly ventured sector, infusion of technical services & appropriate know-how are always a catalyst for the better performance.
- Run project on 3 shifts in peak season of potatoes harvesting as the raw material will be available at cheap price and the quality of Potato powder and flakes will be of high standards, while, it will save cost of storage.
The unit can be installed anywhere in Pakistan where the raw material (fresh potatoes) is easily accessible. As per current agricultural practices, Okara is the largest producer of Potatoes not only in Punjab Province but in Pakistan. In 2014-15, Okara district produced 1.4 million tons of Potatoes which is 37% of the production of Punjab and 34% of the Pakistan’s total Potato Production. Total production of Potatoes in Pakistan during 2014-15 was 4.16 million tons out of which Punjab province is producing 97% of the potatoes production..
Keeping in view the above statistics and availability of raw material (fresh potatoes), the proposed unit will be installed near district Okara in Punjab. Potato Powder imports may be reduced by installation of such processing units.
As stated above Pakistan is importing large quantities of Potato Powder and it is estimated that in future this quantity will increase. This kind of unit and the ones similar will help to reduce the import of such products and make Pakistan capable of exporting Potato Powder to the world.
The targeted customers for these products are food, bakery, agriculture / animal feed, and various other industries. The main export markets for Pakistani processed Potatoes are Middle East, Far East, China, Malaysia, and neighboring countries. Apart from this, local demand can also be met by this unit.
Investment Required for Potato Powder Production in Pakistan
The proposed Potato Powder manufacturing business comprises a total investment of Rs. 312.10 million with fixed investment of Rs. 299.49 million and working capital of Rs. 12.61 million. The Net Present Value (NPV) of the project is Rs. 27.12 million with an Internal Rate of Return (IRR) of 19% and a payback period of 5.41 years. Details of these financials can be studied in the potato powder business plan in Pakistan.