Comparison of conventional frying and microwave frying of beef patty: effect on oil absorption, texture, physical and chemical properties

A comparative study was performed to evaluate the effect of conventional and microwave frying on the quality attributes (moisture, fat, textural properties, colour, and cooking yield) of the beef patty. Experiments were conducted by cooking the beef patties using conventional and microwave frying in two different types of oil (palm oil and corn oil). Two microwave power levels were used (50% and 70%). Microwave frying beef patty showed a significant difference in terms of moisture content, hardness, lightness (L*) and also cooking yield compared to conventional frying. The oil absorption can be reduced when the beef patty was cooked using a microwave. Beef patty fried with the highest microwave power level (70%) by using corn oil has the least oil absorption (18.44±1.04%). The theory of higher moisture loss higher oil uptake does not correspond in this experiment since low-fat content were observed as the moisture decreased for all the beef patties fried using a microwave. Analysis of the hardness of beef patty showed that microwave frying beef patty (corn oil) at a power level of 50% (MF 50%) has the hardest texture (35.48±2.10 kg). Microwave frying beef patty has a lower cooking yield (56.05±2.23 to 71.30±0.89%) compared to conventional frying (86.12±0.45 to 88.60±0.04%). It is also found that there was no significant effect of type of cooking oil on the quality attributes of fried beef patties while different frying techniques were observed to affect the quality of patty

Monitoring the physicochemical features of sunflower oil and French fries during repeated microwave frying and deep-fat frying

This study investigates the effects of repeated microwave frying at different power levels (360W, 600W, 900W) and deep-fat frying on sunflower oil and French fries. The intermittent batch frying cycle was repeated 15 times a day during five consecutive days. The fatty acid profile and physicochemical properties including free fatty acid (FFA), extinction coefficient (K270), total polar compound (TPC), color, viscosity, refractive index of the sunflower oil were determined each day. At the end of the frying period, the highest values of viscosity (76.29cp) and refractive index (1.4738) were detected in microwave frying at 900W power level. TPC level exceeded 25% after the third day of microwave frying at all power levels. The FFA values during microwave frying increased progressively from 0.157% to 0.320- 0.379% on the fifth day. The loss of polyunsaturated fatty acids was 37-53% more in the case of microwave frying. The oil quality during microwave frying did not have a significant impact on the oil absorption and total color change of the French fries. Microwave frying, even at higher levels, provided lower oil (8.60-12.32%wb) and moisture contents (35.47-41.24%) compared to deep frying. Microwave frying caused longer processing time and significantly higher levels of degradation of the sunflower oil at all power levels compared to deep frying. However, microwave frying has the advantage of reducing oil absorption. The oil content of French fries was lowered by 20-33% (wb) at the highest power level.