Effect of palm vitamin E,B-Carotene and *-Tocopherols on lipid oxidation and sensory quality of pound cakes.

A trend in usage of fats and oils in baking industry is to replace plastic fats in baked goods with more unsaturated vegetable oils. Pound cake contains 30-70g fats/100g flour. Utilization of appreciable amount of unsaturated fats in pound cakes will promote oxidative deterioration during storage,resulting in the development of rancid off-flavor.changes in color,texture and nutritive properties. Inaddition to losses in quality,oxidized products may pose potential health risk. The objective of this study was to evaluate the effect of natural antioxidants on lipid oxidation and sensory quality of pound cakes. Each pound cake was prepared from 300g of wheat flour,360g of sugar,400g of margarine and 6.5g of baking powder. Percent of natural antioxidants added was 0.1%,based on the fat content of pound cake. After the cakes were baked (175C,45 min),they were stored at 25C for 0,3,6 and 9 days. Oxidation of cake samples was monitored using thiobarbituric acid test. The antioxidant activities (AOA) of various antioxidants in cake samples were calculated at the end of storage period. Sensory test was conducted to evaluate the flavor,color,texture and overall acceptability of o dy samples. Palm vitamin E exhibited the strongest inhibitory effect (AOA=0.73) on lipid oxidation of pound cakes. The AOA of combined B-carotene/*-tocopherols was significantly (*=0.005) higher than that of the individual antioxidant when used alone. A synergistic antioxidant action was also observed between these two compounds. The concentrations of antioxidants used in this study didi not affect the flavor,color and overall acceptability of cake samples,while samples containing palm vitamin E and *-tocopherols had improved texture. Lipid oxidation has been implicated in a multitude of degenerative diseases,such as cancer,cardiovascular diseases and genetic errors. The addition of these multifunctional antioxidants into pound cakes would serve to inhibit lipid oxidation,provide source of vitamins and protect consumera against diseases

Frying performance of red palm olein, RBD and corn oil.

Red palm olein is a new cooking oil produced in Malaysia. It is carefully processed with stringent quality control to preserve the inherent high contents of B-carotene, tocopherols, and tocotrienols. The high level of natural antioxidants found in red palm olein would contribute to its thermal stability and the antioxidants could also be adsorbed or absorbed into the foods during frying,thereby enhancing the keeping quality of the fried foods. A comparative study was therefore undertaken to evaluate the frying performance of red palm olein,RBD (refined,bleached, and deodorised) palm olein and corn oil. The quality changes of various oil samples during frying at 180C for 3 hr per day for 5 consecutive days were monitored. Thiobarbituric acid (TBA) value,free fatty acids content (FFA),iodine value,color and viscosity of the oil samples were determined. Sensory quality of the prawn crackers fried in these oils and their oxidative stability were also examined. Red palm olein exhibited significantly better oxidative and hydraulic stability during frying (a=0.05). At the end of frying period,TBA values were 54.0,60.9 and 65.8 umoles malonaldehydes/kg oil,while FFA were 0.42,0.48 and 0.53% for red palm olein,RBD palm olein and corn oil respectively. The iodine values decreased by 8.6,9.4 and 16.9g of i2/100g oil,while viscosity increased by 16.8,21.0 and 28.2 centipoise for red palm olein,RBD palm olein and corn oil,respectively

Ascorbate absorption by live channel catfish as a function of ascorbate concentration, pH, and-duration of exposure

Ascorbate uptake by muscle tissue of live channel catfish was affected by ascorbate concentrations (1000, 2000, and 3000 ppm), pH (5, 6, and 7) and duration of exposure (8, 16, and 24 hr.). The most favorable conditions for ascorbate absorption were exposure to 3000 ppm ascorbate at pH 5 for 24 hr. The increased muscle ascorbic acid concentration was 4-fold higher than that of the control group (10 ppm). The ability of live channel catfish to absorb dissolved ascorbate via gills and/or intestines and distribute the antioxidant into muscle tissue provides a new approach to introduce water-soluble antioxidants to aquacultured fish species