Sensory and chemical assessment of pork supplemented with iron and vitamin E

Pork muscle samples (M. longissimus dorsi and M. psoas major) were obtained from pigs given one of four dietary treatments, (1) control diet, (2) supplemental iron (7g iron (II) sulphate/kg feed), (3) supplemental vitamin E (200 mg dl-α-tocopheryl acetate/kg of feed) and (4) supplemental vitamin E+supplemental iron. Vitamin C was supplemented to all dietary treatments to facilitate iron uptake. Vitamin E and iron tissue levels were determined for each treatment. Warmed-over flavour (WOF) was evaluated by a trained sensory panel (n=8) for the four treatments which were cooked and refrigerated at 4 °C for up to 5 days. Thawing loss, driploss and thiobarbituric acid reactive substances (TBARS) were also determined. Vitamin E muscle tissue levels were greatest in the Iron/vitamin E-treated group followed by the vitamin E group, control and iron treated groups, respectively for M. longissimus dorsi. Whereas, for M. psoas major vitamin E tissue levels were in order of magnitude, vitamin E>iron/vitamin E>iron>control group. Iron tissue levels were in the order vitamin E>iron/vitamin E>control>iron for M. longissimus dorsi and iron>vitamin E>control>iron/vitamin E for M. psoas major. Thus, vitamin E and vitamin C promoted non-supplemental iron absorption in the vitamin E-treated group for M. longissimus dorsi and to a lesser extent for M. psoas major. M. psoas major was more susceptible to warmed-over flavour development than M. longissimus dorsi for all treatments as determined by sensory profiling, due to higher tissue iron levels. From sensory profiling, WOF development in M. longissimus dorsi and M. psoas major was highest in the iron-supplemented groups followed by the control and vitamin E-supplemented groups.