Effect of thermal treatment on glucosinolates and antioxidant-related parameters in red cabbage (Brassica oleracea L. ssp. capitata f. rubra)

The effects of various thermal processing treatments (blanching, boiling and steaming) of red cabbage, Brassica oleracea L. ssp. capitata f. rubra cv. ‘Autoro’, were assessed for the levels of glucosinolates (GLS), total phenols (TP), total monomeric anthocyanins (TMA), l-ascorbic acid (L-AA) and soluble sugars, as well as for the antioxidant potential by the ferric reducing ability power (FRAP) and oxygen radical absorbance capacity (ORAC) assays. Individual native GLS were determined by ion-pair HPLC-MS/DAD. There were significant (p < 0.05) losses in blanched red cabbage: TP, 43%, TMA 59%, FRAP 42%, ORAC 51%, L-AA 48% and soluble sugars 45%. Boiling gave less extensive reductions: TP 16%, TMA 41%, FRAP 17%, ORAC 19%, L-AA 24% and soluble sugars 19%. Steaming caused no losses for TP, ORAC, FRAP or soluble sugars. However, significant reductions were found for TMA and L-AA, with 29% and 11%, respectively. In general losses were accounted for in the processing waters; however, TMA was not fully recovered, indicating degradation. Total GLS were severely affected by processing, with reductions of 64%, 38% and 19% in blanched, boiled and steamed red cabbage, respectively. Total aliphatic and indole GLS were similarly affected. Lost GLS were partially recovered in the processing water.     

Acrylamide in potato crisp—the effect of raw material and processing

Reducing sugars and free amino acids were analysed in slices from three potato cultivars before and after blanching (0-3 min). The potato crisps were deep fried at 185 °C for different times (3-8.5 min), and analysed for the concentration of acrylamide (AA) and moisture. Potato cultivar and the temperature during processing were important parameters for AA formation in potato crisps. The amount increased with an increase in the processing time. Blanching before deep-frying reduced the concentration of free asparagine and reducing sugar in the raw material. We found no effect of blanching as pretreatment on the concentration of AA in the potato crisps. Any relationship was not detected between the levels of asparagine in the different cultivars, before and after blanching, and the formation of AA in the crisp products. However, it was shown that the content of reducing sugars determined the level of AA after frying.     

Changes in oat lipids affected by extrusion

During the extrusion of oat flour and its mixtures with starch, changes in lipids occurred being manifested by an increase in peroxide values, and position isomerism of double bonds in the fatty acids. The extrusion resulted in an increased peroxide value in free fat, and bound lipids. The bound lipids of extrudates had an increased percentage of non-polar lipids, the peroxide value of which was lower than of free fat.     

Aging and Enhancement Effects on Quality Characteristics of Beef Strip Steaks

ABSTRACT: Strip loins were removed 48 h postmortem from beef sides ( n = 20 pairs) to assess the effects of enhancement before or after aging on quality attributes of beef strip steaks. Strip loins were enhanced to 108% of original weight to contain 0.4% alkaline phosphate, 0.3% salt, 0.1% natural flavoring (on a final weight basis), and added water for comparison with non-enhanced samples. Regardless of when enhancement occurred relative to aging, enhanced samples were more tender, juicy, and salty than their non-enhanced counterparts. Enhanced samples were lighter, less red and less yellow, and had lower L *, a *, and b * values than non-enhanced samples; however, they generally had lower hue angles indicating that their color was closer to the true red axis of the color scale. Samples enhanced before aging achieved maximum tenderness after 14 d, whereas those enhanced after aging experienced no tenderness changes. Warner- Bratzler shear values were lower and pH values were higher in enhanced steaks than in controls.     

Effect of carbon monoxide and high oxygen modified atmosphere packaging and phosphate enhanced, case-ready pork chops

The objective of this study was to evaluate the effects of CO-MAP compared to traditional high oxygen MAP (HiOx-MAP) packaging and enhanced with different phosphate on enhanced pork quality. Pork loins were enhanced to 10.5% over initial weight to contain 0.3% salt and 0.4% phosphate (either sodium tripolyphosphate [STP] or a blend of STP and sodium hexametaphosphate) on a finished weight basis. Chops were cut, packaged in atmospheres containing 0.4% CO/30.0% CO₂/69.6% N₂ (CO-MAP) or 80% O₂/20% CO₂ (HiOx-MAP), aged in the dark, then placed in a lighted retail display case for 48 h. Chops packaged in CO-MAP were redder (higher Minolta a^* values) and darker (lower Minolta b^* values) than chops packaged in HiOx-MAP. Based on sensory scores, the CO-MAP chops were pinker than the HiOx chops after cooking. CO-MAP chops also experienced less purge loss than chops in HiOx-MAP. Results indicate that CO-MAP had no effect on flavor or consumer acceptability and only minimal effects on other characteristics.     

Effects of Shelf-Life Enhancers on E. coli K12 Survival in Solutions Used to Enhance Beef Strip Steaks

ABSTRACT:  The objective of this study was to evaluate the effects of enhancement solutions containing sodium lactate or sodium lactate/sodium diacetate on E. coli K12 transmission to beef strip steaks and in purge. Solutions containing salt, phosphate, and shelf-life enhancers were injected to 10% over initial weight of the steaks. Lactate or lactate/diacetate addition to a solution inoculated with 6 log₁₀ E. coli K12 CFU/mL was equally effective in limiting growth resulting in a 1-2 log₁₀ CFU/g reduction when compared to salt/phosphate in steaks. When inoculation level was 3 log₁₀ CFU/mL in the enhancement solution, microbial growth was detectable only in the purge of steaks enhanced with salt/phosphate only. Lactate increased CIE L* value and b* and decreased a* values when compared to the control. Lactate-/diacetate-containing solutions decreased L* values when compared to lactate alone. Lactate/diacetate also reduced purge loss from steaks compared to lactate and salt/phosphate solutions.     

A multilevel,multicomponent childhood obesity prevention group-randomized controlled trial improves healthier food purchasing and reduces sweet-snack consumption among low-income African-American youth

Long chain polyunsaturated fatty acids (LCPUFA) especially docosahexaenoic acid (DHA) and arachidonic acid (AA) are crucial for normal brain development in utero and in early infancy. Data on fatty acid status and cognitive development in infants and children from low-income countries are scarce. We examined the association between the DHA and AA status in infancy (n = 320) and developmental status and cognitive functioning five years later. At five years of age, we measured development by the Ages and Stages Questionnaire 3rd. ed. (ASQ-3) and cognitive functioning by subtests from the neuropsychological test battery NEPSY II. In addition, infant fatty acid composition in red blood cells (RBC) was analyzed. In multiple linear and logistic regression models, we estimated the associations between DHA and AA status in infancy and scores on the ASQ-3 and the NEPSY II subtests. There were no notable associations between infant AA and DHA status, and the scores on the ASQ-3 and the NEPSY II subtests five years later. It should be noted that we found better than expected concentrations of erythrocyte DHA and AA among the infants, and the ASQ scores were left-skewed, which limited the ability to identify associations. DHA and AA status in infancy is seemingly not related to neurodevelopment measured 5 years later in this peri-urban population from Nepal.     

The influence of complexing agents on the solubility and absorption of aluminium in rats exposed to aluminium in water

The influence of citrate (0-31mm), fluoride (0 or 2.6mM) and silicate (0 or 2.6mM) on the absorption of Al (0-18mM) was studied in rats. We tested the hypothesis that the solubility and absorption of Al increases in the gastrointestinal (GI) tract in the presence of the complexing agents. Male rats were exposed for 6 or 7 weeks to soluble Al in acidic drinking water (pH 2.5-3.0) with or without the complexing agents. At the end of exposure Al was fractionated in the stomach content, in order to study if the solubility of Al was changed after ingestion. Al absorption was estimated by Al analysis of the right femur bone. Speciation calculations indicated that citrate and fluoride caused formation of soluble Al-citrate (97%) and -fluoride (>60%) complexes in the water. Silicate did not affect the theoretical speciation. In all cases, a large fraction of soluble Al became insoluble in the stomach after ingestion. The concentration of soluble Al increased only in the presence of citrate or a mixture of fluoride and silicate, but citrate was the only complexing agent that influenced the absorption of Al in the rat. This indicates that the form of Al may be changed in the GI tract when soluble drinking-water Al is ingested, and that the solubility of Al in drinking water and GI tract may not be good predictors of the bioavailability of Al even when chelating agents are present.     

Growth and metabolism of selected strains of probiotic bacteria, in maize porridge with added malted barley

A fermented probiotic maize porridge with high energy density and low viscosity was prepared, using maize flour and barley malt. The porridge was fermented with four probiotic strains (grown separately): Lactobacillus reuteri, Lb. acidophilus (LA5 and 1748) and Lb. rhamnosus GG. These strains were inoculated at two levels; to obtain approx. 7 or 6 log cfu g(-1) in the porridge at 0 h. The porridge was fermented for 24 h at 37 degrees C, and analysed for viable cell count, pH, organic acids, volatile aromatic compounds and sugar content. The inoculated cell concentration was shown to be particularly important during the first hours of the fermentation period, showing a delayed production of most metabolites in porridge inoculated with approx. 6 log cfu g(-1). Most strains reached maximum cell count after 12-h fermentation (7.2-8.2 log cfu g(-1)), with a pH below 4.0. Depending on the strain, lactic acid was produced in amounts ranging from 1360 to 4000 mg kg(-1). Lb. reuteri metabolised succinate, while pyruvate and small amounts of diacetyl were detected in porridge inoculated with Lb. acidophilus LA5 and Lb. acidophilus 1748. High amounts of diacetyl (6 mg kg(-1)) and acetoin (27 mg kg(-1)) were detected in porridge inoculated with Lb. rhamnosus GG. Porridge inoculated with Lb. acidophilus LA5 and Lb. acidophilus 1748, contained acetaldehyde, while both Lb. reuteri and Lb. rhamnosus GG reduced the acetaldehyde to ethanol. Lb. reuteri utilised both maltose and glucose as carbohydrate sources, while Lb. acidophilus LA5, Lb. acidophilus 1748 and Lb. rhamnosus GG utilised only glucose.