14A-11

M. S. Chinnan¹, K. S. PANNU², A. E. Reynolds³, and R. Bheemreddy¹. (1) Center for Food Safety and Quality Enhancement, University of Georgia, 1109 Experiment Street, Griffin, 30223-1797, (2) Biological Systems Engineering, Washington State University, Pullman, WA 99164-6120, (3) Food Science and Technology Extension, University of Georgia, Athens, GA 30602

The food industry is interested in means to improve and extend the usability of frying oils utilized for the cooking of food products. Cleansing of the oil with FDA-approved adsorbent materials can accomplish this task. Information on the frying characteristics of treated oil is needed.

Our objectives were to examine the oil uptake by food fried in fresh-, daily-abused-, and treated-oil (treated with adsorbent materials), and to determine overall heat transfer coefficient and oil quality.

Four (A, B, C and D) pot fryers (2.7 kg oil capacity) were used. Food batches (340 gm of breaded chicken fillets and/or French-fries) were fried (at 180 °C for 5 min) every 20 minutes over a 7.5-hr period daily for 8 days. Oil from fryers A, B and C was combined at the end of each day, 1% (by weight) of a special adsorbent added, and then filtered through a specially designed filtration unit. Beginning of second through eighth day the treated oil composition in fryers A, B and C was adjusted to 33, 67, and 100%, respectively.

Oil absorbed by the food was the same for all the fryers, and for all of the 8 days. The oil absorption level remained close to the 1% level for the first 6 days and thereafter increased to approximately 3.6% for days 7 and 8. This increase was attributed to the variation in the product quality rather than the change in the oil quality. Heat transfer coefficients determined with metal balls were similar for all fryers over the 8-day period (~ 250 W/m^2oC). FFA values for the daily-abused oil increased from 0.05% to 1.55% over the 8-day period, but remained below 1% level for adsorbent-treated oil.

Daily treatment of abused oil with suitable chemical adsorbent(s) has a great potential in enhancing the usable life of frying oil.