Explosion puffing

One problem with high porosity in dehydrated foods, in addition to increased packaging requirements, is the possibility of rapid oxidation because of increased surface area of exposure to oxygen if air is present within the pores. An approach which could be used to solve the problem was first suggested by Sinnam et al. (20) when they compressed explosion puffed carrots after dehydration and found that there were no differences in the rehydration rate or rehydration ratio compared to the original explosion puffed dehydrated carrots. This concept has been extensively exploited by the U.S. Army Natick Laboratories (21) in the development of... 

Sinnam, H. L. Eskew, R. K. Cording, J. Dehydrated Explosion Puffed Carrots with High Density, U.S. Department of Agriculture, ARS 73-50, 1965. 

Explosion puffing is the oldest technique used to create starch-based foams from starch feedstock with low moisture content. A typical example of this is making popcorn a kernel explosion puffs naturally at about 177 °C and requires only 10-15 % moisture to achieve maximum volume [146]. Explosion puffing can produce low-density starch-based foams within several seconds, however the performance of the foamed products is poor. 

The gun used in batch model explosion puffing was essentially a rotating cylindrical pressure chamber that was fitted with a quick-release lid, and was heated externally. The rotational speed of the gun was fixed to give an optimal tumbling action of the charge. This speed (33 rpm) was about 40% of the critical speed, that is, the speed at... 

FIGURE 29.5 Schematic diagram identifying major components of continuous explosion puffing systems. (From Heiland, W.K., Food... 

Process Conditions for Explosive Puffing (Batch and Continuous) of Some Vegetables and Fruits... 

Explosion puffing , developed by American researchers in the 1960s and applied to fruit and vegetable pieces (mushroom, celery, onion, pepper, pear, pineapple, strawberry, and cranberry) (Kozempel et al., 1989 Jayaraman and Das Gupta, 1992). The product is heated to 150-200 °C under pressure, and then suddenly expanded to atmospheric pressure. 

FIGURE 2S.S Schematic diagram identifying major components of continuous explosion puffing systems. (From Heiland, W.K., Sullivan, J.F., Konstance, R.P., Craig, J.C., Jr., Cording, J., Jr., and Aceto, N.C., Food Technol., 31(11), 32, 1977. With permission.)... 

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