Fried foods

A good compilation of the functions of fats in various food products is available (26). Some functions are quite subtle, eg, fats lend sheen, color, color development, and crystallinity. One of the principal roles is that of texture modification which includes viscosity, tenderness (shortening), control of ice crystals, elasticity, and flakiness, as in puff pastry. Fats also contribute to moisture retention, flavor in cultured dairy products, and heat transfer in deep fried foods. For the new technology of microwave cooking, fats assist in the distribution of the heating patterns of microwave cooking. 

Hydrogels are used ia the refining of edible oils to adsorb phosphohpids, trace metals, and soaps (103). The adsorption capacity depends on the ease of hydration of the adsorbates, so best performance demands careful control of moisture content ia the system (104). Sihca hydrogel ia combination with alumiaa has beea fouad to be useful for purifyiag used cooking oils ia order to extead their life and enhance the quahty of the fried food (105). 

The destruction of antioxidants in fried food is much lower than in frying oil as the contact of food with frying oil is only short. Antioxidants are oxidised only in the surface layers. The deep frying takes only a few minutes so that only the outer layers of deep fried food are heated to 150-180°C, but the inner layers are not oxidised to more than 100°C in such a short time. Therefore, losses of antioxidants in the inner layers are negligible. Many food components, such as proteins, flavonoids or tannins, inhibit the destruction of antioxidants in fried food during the frying operation (Pokorny, 2000). 

Oxidation reactions of fried food occur rather intensively on storage as the thin film of flying oil left on the surface of fried food is easily attacked by oxygen from the air. The stabilisation of fried food against oxidation on storage thus offers a more important problem than does oxidation during the flying operation. 

JASWIR I, MAN Y B c and KITTS D D (2000) Use of natural antioxidants in refined pahn olein during repeated deep-fat frying, Food Res Int, 33, 501-8. 

Acceptability of food is dependent on a knowledge of its ingredients e.g. how pure is the drinking water or is there acrylamide in french fries or other fried food preparations, how much vitamin C, or li-carotene, or proline is there in juices, what preservatives are there in bread, sausages or other food preparations Alloys have to meet certain specifications to be used in tools, machinery or instraments. The price of platinum ores or used catalytic converters from cars depends on the platinum content. There are many more examples. This shows the importance of correct analytical results. 

Abstract One of the most important quality parameters of fried food is the... 

One of the most important quality parameters of fried food is the amount of fat absorbed during the process, which is incompatible with recent consumer trends toward healthier food and low-fat products (Bouchon... 

The influence of the oil type and quality on oil absorption and residues absorbed by fried foods is widely documented (e.g., Blumenthal, 1991 Blumenthal and Stier, 1991 Krokida et al., 2000 Nonaka et al, 1977 Pokomy, 1980). No relationship has been found between oil type and oil absorption however, it has been shown that an increase in the initial interfacial tension between oil and restructured potato products decreases oil absorption (Pinthus and Saguy, 1994). Further, as mentioned earlier, oil degradation produces surfactants that act as wetting agents, which also increase the absorption (Blumenthal, 1991). 

Blumenthal, M. M. (1991). A new look at the chemistry and physics of deep-fat frying. Food Technol. 45, 68-71. 

Gazmuri, A. M. and Bouchon, P. (2009). Analysis of wheat gluten and starch matrices during deep-fat frying. Food Chem. doi 10.1016/j.foodchem.2009.01.020. 

Gillat, P. (2001). Flavour and aroma development in frying and fried food. In "Frying Improving Quality" (J. B. Rossell, ed.), pp. 266-366. CRC Press Inc., Boca Raton, FL. 

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. 

Hubbard, L. J. and Farkas, B. E. (1999). A method for determining the convective heat transfer coefficient during immersion frying. ]. Food Process Eng. 22, 201-214. 

Krokida, M. K., Oreopoulou, V., Maroulis, Z. B., and Marinos-Kouris, D. (2001b). Effect of osmotic dehydration pretreatment on quality of French fries.. Food Eng. 49, 339-345. 

Mellema, M. (2003). Mechanism and reduction of fat uptake in deep-fat fried foods. Trend. Food Sci. Technol. 14, 364—373. 

Melton, S. L., Jafar, S., Sykes, D., and Trigiano, M. K. (1994). Review of stability measurements for frying oils and fried food flavor. ]. Am. Oils Chem. Soc. 71, 1301-1308. 

Moreno, M. C. and Bouchon, P. (2008). A different perspective to study the effect of freeze, air, and osmotic drying on oil absorption during potato frying. ]. Food Sci. 73, E122-E128. 

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