Formation during frying

The mechanism of NPYR formation has been studied by Coleman (37) and Bharucha et al. ( ). Coleman (37) reported that the requirement for a high temperature, the inhibitory effects of water and antioxidants, and the catalytic effect of a lipid hydroperoxide are consistent with the involvement of a free radical in the formation of NPYR. Similarly, Bharucha et al. (29) suggested that, since both NPYR and NDMA increase substantially towards the end of the frying process, N-nitros-amine formation during frying of bacon occurs essentially, if not entirely, in the fat phase after the bulk of the water is removed and therefore by a radical rather than an ionic mechanism. These authors speculated that, during the frying of... 

The inhibition of formation of NPYR and NDMA in fried bacon by the use of cure-solubilized a-tocopherol (500 mg/kg) has been demonstrated by Fiddler et al. (50). Walters et al. (53) also reported reduced levels of N-nitrosamines in the vapors during the frying of bacon in fat containing a-tocopherol. It has also been shown that a-tocopherol is dispersed quite effectively during frying of bacon slices therefore, application to bacon may be made by spray or dip to overcome the problem of water insolubility (51). Controlled addition of this antioxidant may be an effective and practical way of reducing the concentration of N-nitrosamines in cooked... 

If a convenience product such as cowpea meal is to find favor with the consumer, it must produce an end product which is similar in quality to that produced by the traditional process. Essential to attainment of a light, spongy texture in the fried product is the formation, during the whipping of cowpea paste, of a foam with appropriate volume and consistency. 

In some recent research on flavor formation during deep-fat frying at Rutgers University, a number of heterocyclic compounds with long-chain alkyl substituents were found the volatiles of fried chicken (15) and fried potato (16). These included pyridines, thiazoles, oxazoles, trithiolanes and a pyrazine. Only the involvement of lipids or lipid degradation products in the formation of... 

As shown in Figure 2-23, oil breakdown during frying can be caused by oxidation and thermal alteration. Oxidation can result in the formation of oxidized monomeric, dimeric, and oligomeric triglycerides as well as volatile compounds including aldehydes, ketones, alcohols, and hydrocarbons. In addition, oxidized sterols may be formed. Thermal degra-... 

Ateba, P. and Mittal, G. S. (1994). Dynamics of crust formation and kinetics of quality changes during frying of meatballs. Journal of Food Science, 59(6), 1275-1278. 

Razali, I. and Badri, M. (1993) Oil absorption, polymer, and polar compounds formation during deep fat frying of french fries in vegetable oils, in Proceedings of the 1993 PORIM International Congress, Update and Vision (ed Y. Basiron), Kuala Lumpur, pp. 80-89. 

Cake doughnuts. 2 to 4% defatted SF improves structure, gives an excellent star formation (hole), and reduces fat absorption during frying. The improved moisture retention improves product yield and shelf life. 

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