Deloy G. Hendricks

A comparison of carnosine and ascorbic acid on color and lipid stability in a ground beef pattie model system.

Ascorbic acid (0.1%) significantly inhibited metmyoglobin formation on the surface of ground beef but not in the bulk of the product where oxygen tension was lower. Carnosine (1.0%), however, significantly inhibited metmyoglobin formation and brown color development throughout the product. The combinations of carnosine and ascorbic acid were also very effective on inhibition of metmyoglobin formation and brown color development. Carnosine increased meat pH, cook yield and salt-soluble protein, but ascorbic acid had no effect on cook yield, and decreased meat pH and salt-soluble protein. Carnosine was more effective on inhibition of lipid peroxidation than ascorbic acid. Carnosine inhibited copper(II)-catalyzed ascorbate oxidation in a dose-dependent manner in model systems. Carnosine in conjunction with ascorbic acid may be useful as a meat additive for increasing shelf-life as well as stabilizing color of meat products.

Effect of sodium phytate, sodium pyrophosphate and sodium tripolyphosphate on physico-chemical characteristics of restructured beef☆

The effects of 0.5% sodium phytate (SPT), sodium pyrophosphate (SPP), and sodium tripolyphosphate (STPP), along with 1% NaCl, on physico-chemical properties of restructured raw and cooked beef were evaluated. In raw beef stored for 1 day at 4 ° C, the SPT, SPP, and STPP increased pH and salt-soluble protein level and decreased %MetMb and thiobarbituric acid reactive substances (TBARS), compared to the control with salt alone (p < 0.05). In cooked beef, SPT, SPP, and STPP increased bind strength, cook yield, moisture level, and pH, and decreased TBARS (p < 0.05). SPP and STPP increased orthophosphate in both raw and cooked beef (p < 0.05), compared to the SPT and control. SPT, SPP, and STPP decreased the Hunter color L and b values and increased a value in raw beef (p < 0.05) but had no effect on the Hunter color values in cooked beef. The binding value of SPP and STPP were similar over time, and the time to reach maximum binding strength was 10s longer than SPT and 25s longer than the control. These results indicate that SPT compares favorably with traditional phosphates for bind strength and cooked yield, but SPT was slightly more effective than other phosphates for reduction of TBARS 1 day after cooking.

Efficiency of converting food iron into hemoglobin by the anemic rat.

The bioavailability of iron in dried whole egg, ground beef, whole-wheat flour, enriched flour and FeSO4 was evaluated in terms of hemoglobin regeneration. Sixty weanling male rats were made anemic by feeding a semi-purified basal diet containing 7.8 p.p.m. iron. They were divided into six groups to be fed the basal diet or the basal diet substituted with appropriate amounts of each iron source for 3 weeks. It was calculated that the milligrams of iron converted to hemoglobin per 100 mg of iron consumed was 51 for the iron in FeSO4 diet, 45 for the iron in egg diet, 43 for the iron in beef diet, 33 for the iron in whole-wheat flour diet and 24 for the iron in enriched flour diet. The efficiency of converting iron in FeSO4 diets to hemoglobin iron is linear over a wide range of iron intakes between experiments and among laboratories.

Potential of the rat as a model for predicting iron bioavailability for humans

The absorption of iron by iron deficient and normal rats and humans was compared. Qualitatively, rats and humans respond similarly to many dietary and physiological factors known to affect iron utilization. It was found that iron absorption by rats was highly correlated (r=0.94) with that of humans. The average human response was 68 percent that by the rats.

Fasting and ketogenic diet effects on audiogenic seizure susceptibility of magnesium deficient rats

Because fasting and ketogenic diets decrease seizure susceptibility in epileptics, their anticonvulsant effects were studied using sound-induced seizures in the magnesium-deficient rat. Fasting markedly depressed seizure incidence and severity but did not affect latency (sec to seizure onset). High-fat diet increased incidence of audiogenic seizures and seizure severity, and decreased latency. Gavage of medium chain triglyceride, beta-hydroxybutyrate or glucose did not affect seizure incidence, seizure severity or latency. Nonspecific excitability level was not associated with treatment nor with seizure incidence, severity or latency time.

Parent Involvement in Nutrition Education for Primary Grade Students.

Abstract Three schools were matched for socioeconomic status, location, and comparability of teachers, physical facilities, and other education resources. Students in kindergarten through grade three in two schools received nutrition education; the third school served as a control. At one of the two treatment schools, the parents also received education in nutrition. At the end of the four-month treatment period, 24-hour food frequency recalls revealed that parents who participated in the nutrition education program reported that their children were consuming a higher quality diet and a wider variety of foods compared with students in either of the other two schools. Cognitive scores for kindergarten and first grade students also were significantly higher for children in the school with parent involvement. The results support the importance of a parent education component in achieving a positive effect in food behavior as a result of a nutrition education program.

Effects of Calcium Solubility on Absorption by Rats with Induced Achlorhydria

Gastric X-irradiated, achlorhydric rats and sham-operated controls were fed diets containing very soluble calcium chloride or calcium gluconate or slightly soluble calcium carbonate or tricalcium phosphate for 3 weeks. Calcium was absorbed more efficiently by achlorhydric rats from the very soluble salts from the slihtly soluble salts. The control rats absorbed calcium from the very soluble and slightly soluble calcium salts with similar efficiency. Achlorhydric rats fed slightly soluble calcium salts developed weaker bones with a lower mineral content than did those fed very soluble calcium. Apparently, the very soluble dietary calcium offset the impaired calcium absorption of achlorhydric rats. Calcium solubility had no significant effect on the bones of control animals.

Effect of coprophagy on bioavailability of iron from plant foods fed to anemic rats.

Effects of coprophagy and coprophagy preventing device on iron bioavailability were evaluated in two experiments. In Experiment 1, rats were fed diets with FeSO4, spinach, bran cereal or cornmeal as the iron source. The rats in each diet group were fitted with collars, sham-collars or not fitted with collars (control). In Experiment 2, rats were fed diets with FeSo4 or green peas as the iron source and were fitted with collars, tail cups, sham-collars or not fitted with any device (control). Preventing coprophagy reduced hemoglobin regeneration efficiency (HRE) of rats fed bran cereal, green peas, spinach or cornmeal diets by 26 (P<.05), 24(P<.05), 22(P<.05) and 11% (not significant), respectively. Preventing coprophagy in rats fed FeSO4 diet did not significantly reduce HRE. Sham-collaring reduced (P<.05) HRE of rats fed the FeSO4 diet by 12 and 13% but did not significantly affect HRE in rats fed food iron sources. It was more convenient and effective to prevent coprophagy with collars than with tail cups. Differences in bioavailability between food and FeSO4 iron due to coprophagy may be explained based on two gastrointestinal nonheme iron pools, complexed and highly soluble.

Effects of cerebral intraventricular magnesium injections and a low magnesium diet on nonspecific excitability level, audiogenic seizure susceptibility and serotonin

Cerebral intraventricular injections of 17 and 50 microgram magnesium in artificial cerebrospinal fluid progressively depressed the Non-specific Excitability Level of permanently cannulated 150--200 g rats fed a low magnesium diet for 21 days. Compared with control diet, a low Mg diet caused an increase in brain serotonin. Weanling rats fed a low Mg diet for 2 weeks, then injected with 25 microgram Mg via acute cannulations, displayed reduced audiogenic seizure susceptibility compared with sham-injected controls.

Effect of magnesium deficiency on nonspecific excitability level (NEL) and audiogenic seizure susceptibility

Magnesium deficiency in weanling rats caused an increase in NEL and in audiogenic seizure susceptibility. These behavioral effects were apparent after eight days of magnesium restriction and could be reversed by dietary rehabilitation. Serum magnesium declined rapidly from 1.87 +/- 0.10 mEq/L to 0.91 +/- 0.24 mEq/L in two days. Cerebrospinal fluid (CSF) magnesium decreased gradually from 1.86 mEq/L, becoming significantly lower (1.44 +/- 0.23 mEq/L) after eight days. When deficient rats were injected IP with MgCl2, raising the serum magnesium concentration to 6.6 mEq/L, NEL decreased to normal while audiogenic seizure susceptibility remained. Both NEL and audiogenic seizure susceptibility in rats reflect central nervous system magnesium concentration, except when serum magnesium concentration is very high. Very high serum magnesium concentration lowers NEL but does not reduce audiogenic seizure susceptibility if CSF magnesium is low.