Spray drying advantages

The acid process has three advantages over the alkaline process, ie, (/) higher yield of phosphine (60 vs 25%) (2) more pure gas for use in subsequent reactions (95 vs 40%) and (J) by-product phosphoric acid is relatively valuable and can be sold into a number of markets, eg, in the manufacture of fertilizers and flame retardants. There is no ready outlet for the mixture of phosphites produced via the alkaline route and additional processing by oxidative spray drying is needed to produce phosphates for sale (3). 

Other types are available that use sonic energy (from gas streams), ultrasonic energy (electronic), and electrostatic energy, but they are less commonly used in process industries. See Table 14-11 for a sum-maiy of the advantages/disadvantages of the different type units. An expanded discussion is given by Masters [Spray Drying Handbook, Wiley, New York, (1991)]. 

The introduction of concentrated laundry detergent powders in Japan during 1986-1987 produced a substantial increase in the consumption of LAB in the subsequent 3-4 years as the market changed from low-density, spray-dried powders to the concentrated (compact) products. In these products, which may contain up to 40% surfactant, the cost/performance advantages of LAS are of significance. In addition, LAB sulfonic acid is well suited for the production of high-active, high-density (about 1.0 g/cm3) laundry powders by routes other... 

Since the 1940s, alkanesulfonates have served as emulsifiers in the emulsion polymerization of vinylchloride. Nevertheless, the detailed mechanisms of this process are not yet completely known. An important advantage of using alkanesulfonates is that they produce latices with a high solid content, which can be effectively processed by spray drying [90]. 

Soya Proteins. Early attempts to make albumen substitutes from soya protein also ran into problems. A bean flavour tended to appear in the finished product. A solution to these problems has been found. Whipping agents based on enzyme modified soy proteins are now available. The advantage of enzymatic modification is that by appropriate choice of enzymes the protein can be modified in a very controlled way. Chemical treatment would be far less specific. In making these materials the manufacturer has control of the substrate and the enzyme, allowing the final product to be almost made to order. The substrates used are oil-free soy flakes or flour or soy protein concentrate or isolate. The enzymes to use are chosen from a combination of pepsin, papain, ficin, trypsin or bacterial proteases. The substrate will be treated with one or more enzymes under carefully controlled conditions. The finished product is then spray dried. 

Emphasis is placed on the atomization processes used in spray combustion and spray drying from which many atomization processes have evolved. Advantages and limitations of the atomization systems are discussed along with typical ranges of operation conditions, design characteristics, and actual and potential applications. The physical properties of some normal liquids are listed in Table... 

Ultrasonic sprays produced via horns are also finding use in spray drying installations where there are clear advantages in producing minimal particle velocity with a controlled particle size through a non-clogging nozzle. 

The advantages of spray-dried flavours are the high flavour load and the fast release. The process is very economical. A disadvantages of the flavour powder is the physical demixing in dry blends with sugar, tea, cereals or granulates. 

A particular advantage of the compacted granules is the flexibility of the particle size. Each size between 0.5 and 5.0 mm is adjustable. A further advantage is shaped particles, colour and a combination of spray-dried flavour and additives (vitamins, minerals, functional food ingredients) can be combined in the granulated matrix. 

Spray-drying costs are always a factor in determining the economics of an encapsulated product. Drying costs are related to the amount of water that must be removed in the spray-drying process. It is therefore advantageous to enter the drier at the highest possible solids that still gives... 

While there is no direct data to support this statement, we have found vastly different shelf-lives for products which contain essentially similiar trace metal levels, surface oils, and absolute densities. We can find no other explanation for the differences in shelf-life other than matrix porosity. This area needs to be further studied in order to confirm this hypothesis and then take advantage of it to improve the shelf-life of spray dried flavorings. 

This is particularly important in beverage applications where viscosity cannot be increased to help stabilize the flavor emulsion. These are the three disinct advantages of creating finer emulsions for spray drying citrus oils. While the emulsion size is only one factor which can influence the stability of spray-dried citrus oils, it may be possible to use this information in conjunction with other data and information to manufacture a product with an extended shelf-life, better emulsion stablity, and higher flavor load. 

A remarkable advantage of cyclodextrin complexed flavor fonnulations over spray-dried and micro-encapsulated ones is their negligable hygroscopicity under high humidity conditions. 

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