How to transfer high-viscosity liquids
Viscosity is defined as the “ interaction between the different molecules in a fluid – this can be also understood as friction between the molecules in the fluid ” and can be measured with various types of viscometers and rheometers using the measurement of centipoise ( cP ). When creating produce for consumption , manufacturers need to understand the effect created by food and beverage viscosity , which can be affected by the conditions within which it ’ s used , and are an important consideration when determining manufacturing methods .
Examples of different food and beverage items and their approximate viscosities are noted in the table to the right :
Depending on the viscosity of the product , the pressure and flow rate needed to propel the produce out of its primary container and into its intended location will differ . For example , a thicker , more viscous product will require an increased force versus that of a runnier , more water-like product . The latter is generally easier to transfer because it can be helped by gravity and has less resistance . For many products , however , consumer perception is that the ‘ thicker ’ a product is , the more superior it is , as it is perceived to have been made with higher quality ingredients . This leads to many products being more viscous than they may actually need to be due to consumer perception driving sales , especially for example , beauty products like creams , hair conditioner or shower gel ; and even household products like bleach , washing up liquid or laundry detergent . Working with high viscosities is usually far more challenging for flow-control engineers who need to move fluids through manufacturing lines , ensuring that the liquid is transferred at the correct speed ,
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Product ( at room temperature unless specified )
Viscosity ( centipoise cP )
Acetate glue 1200-1400 Anti-freeze 15 Baby food 1400 Balsamic vinegar 1.05 - 1.30 Black liquid soap 7,000 Bleach ( household 5 - 6 % sodium hypochlorite ) 1.53 Brewers yeast 368 Butter fat @ 43 ° C 42
Caster oil 250 - 500 Citrus fruit pulp 600 Chocolate ( 49 ° C ) 17,000 Chocolate syrup 10,000 - 25,000 Cocoa butter ( 60 ° C ) 50 Condensed milk ( 75 % solids ) 2,160 Corn syrup 2,000 - 3,000 Fabric conditioner 1,500 - 2,000 Face cream 100,000 Glucose 4,300 - 8,600 Hair shampoo 3,000 Honey 2,000 - 3,000 Jam garnish 8,500 Laundry detergent 1,500 Liquid soap 82 Mayonnaise 20,000 Metallic auto paints 220 Milk 2 Milk condensed 40 - 80 Olive oil 40 Orange Juice Concentrate - 30 Brix 630 Orange Juice Concentrate - 60 Brix 2,410 Peanut butter 150,000 - 250,000 Printers Ink 550 - 2,200 Resin solution ( from 18 ° C to 24 ° C ) 880 - 7,140 Salad cream 1,300 - 2,600 Tomato ketchup 50,000 - 70,000 Toothpaste 70,000 - 100,000 Varnish paint 140 Water 1 Yoghurt 152
without damage and without waste . But it ’ s not just the baseline viscosity of the produce that needs to be taken into consideration , there are a few scenarios that can impact the viscosity and therefore change the properties of the product :