Vacuum frying

Dueik, V. and Bouchon, P. (2009). Vacuum frying An advanced technology able to overcome most of detrimental changes occurring during atmospheric frying. Criti. Rev. Food Sci. Nutr. (submitted). 

Granda, C., Moreira, R. G., and Tichy, S. E. (2004). Reduction of acrylamide formation in potato chips by low-temperature vacuum frying. ]. Food Sci. 69, 405—411. 

Mariscal, M. and Bouchon, P. (2008). Comparison between atmospheric and vacuum frying of apple slices. Food Chem. 107(4), 1561-1569. 

Shyu, S. L. and Hwang, L. S. (2001). Effects of processing conditions on the quality of vacuum fried apple chips. Food Res. Int. 34,133-142. 

Available from Kay-Fries Chemicals, Inc., 180 Madison Avenue, New York. This liquid was purified by vacuum distillation (b.p. 78 to 80° at 18 mm.) before use. 

Vacuum fryers are less common but used to fry products where the product is required to maintain most of its natural color. This is mostly used for frying sliced fruits and certain vegetables. 

A vacuum fryer is used to fry fruits or vegetables where it is important to retain the original product color with minimum browning. These fryers generally do not have high production capacity. They are also very expensive. Most commonly used fryers of this category are batch type. Continuous vacuum fryers are extremely costly and are hardly used. These fryers have several distinctive features, such as ... 

The frying is conducted at roughly 250°F (121.1°C). The food can be dehydrated at this temperature under vacuum. 

Carboxylic acid formation [quantum yield 8xl0 m elnst ( )] is a much more efficient process than CO elimination or Photo Fries rearrangement observed during vacuum irradiation (Table l). Carboxylic acid formation in PmPiPA films and fibers has been observed by IR spectroscopy (at 1T20 cm ) and by potentiometrlc titrations on dissolved samples ( ). 

Troncoso, E., Pedreschi, R, and Zuniga, R. N. (2009). Comparative study of physical and sensory properties of pre-treated potato slices during vacuum and atmospheric frying. LWT—Food Science and Technology, 42(1), 187-195. 

Pressure drop across a mesh pad is usually less than 1 in. H20 and is of little concern except in vacuum operations or systems involving large flows with fans or blowers at near atmospheric pressure. Pressure drop is estimated by Ap pc,. where Ap is the pressure drop (in in. H50), Vc is the gas velocity (in fris), and pc (he vapor density (in Ibn/ft. C = 0.2 for a standard-density 4 in. thick pad, and C = 0,12 for a low-density 6 in. thick pad. For situations where pressure drop is critical, methods presented... 

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