Solubilisation of proteins from rayfish residues by endogenous and commercial enzymes

The aim of the present study was to design methods for the digestion of fish proteins from processing wastes, leading to new possibilities for little‐used species or those generating a significant volume of residues. Residues of rayfish (Raja clavata) were used for the solubilisation of protein by hydrolysis treatment. The kinetics of hydrolysis was studied using rayfish enzymes, either by autolysis of the protein in a triturate of the raw material or by application of a multi‐enzyme preparation previously extracted from the viscera of the species. Their effectiveness was compared with that of two commercial enzymes, papain and pepsin. Optimum conditions of hydrolysis and enzymatic activity for digestion with rayfish enzymes were ascertained. The yield of material and the efficiency of digestion in each of the hydrolysis processes are reported. Copyright © 2003 Society of Chemical Industry     

Effect of finishing and ageing time on quality attributes of loin from the meat of Holstein–Fresian cull cows

The effects of finishing time, (T0 = 0, T1 = 30 and T2 = 60 days), on Holstein–Friesian cull cows (n = 18) and post-mortem ageing, (1, 7, 14, 21, 35 and 42 days), under vacuum conditions of Longissimus thoracis (LT) muscles were investigated. The objective of this research was to study how finishing feeding (based on a commercial concentrate and corn silage), following a pasture period of 90 days, affected carcass and meat quality. Ageing time effect was also evaluated on the main quality attribute of added value pieces, such as “striploin of ox” from cull cows. Finishing treatment affected intramuscular fat content (IMF), moisture percentage, water-holding capacity (WHC), colour parameters and shear force of meat at 24 h post-mortem, whereas ageing time enhanced meat tenderness, when this was measured by two textural tests, Warner–Braztler (WB) and textural profile analysis (TPA). A minimum shear force was achieved at 7 and 14 days of ageing for T1 and T2, respectively. No differences (P > 0.05) could be found in colour parameters from 7 to 42 days. The results show that a finishing time of two months is very beneficial, due to the increase in meat fatness, improved overall carcass quality and luminosity (L*). Furthermore, 14 ageing days were sufficient to improved tenderness. Ageing time did not have an effect on lipid oxidation (P > 0.05) and this leads us to conclude that meat shelf life exceeded 42 days under vacuum conditions’.     

Effect of Gamma Radiation and Oregano Essential Oil on Murein and ATP Concentration of Staphylococcus aureus

ABSTRACT:  The study was carried out to evaluate the effects of gamma-irradiation alone or in combination with oregano essential oil on murein composition of  Staphylococcus aureus  and on the intracellular and extracellular concentration of ATP. The bacterial strain was treated with 3 irradiation doses: 1.2 kGy to induce cell damage, 2.9 kGy to obtain a viable but nonculturable state, and 3.5 kGy to cause cell death. Oregano essential oil was used at 0.010% and 0.013% (w/v), which is the minimum inhibitory concentration (MIC). All treatments had a significant effect ( P  ≤ 0.05) on the murein composition, although some muropeptides did not seem to be affected by the treatment. Each treatment influenced differently the relative percentage and number of muropeptides. There was a significant ( P  ≤ 0.05) correlation between the reduction of intracellular ATP and increase in extracellular ATP following treatment of the cells with oregano oil. The reduction of intracellular ATP was even more important when essential oil was combined with irradiation. Also, irradiation alone of  S. aureus  induced a significant decrease ( P  ≤ 0.05) of the internal ATP and a significant increase ( P  ≤ 0.05) of the external ATP. However, no significant difference ( P  > 0.05) was observed in ATP concentrations between different radiation doses. Transmission electron microscopic observation revealed that oregano oil and irradiation have an effect on cell wall structure.     

Foodborne illness outbreaks from microbial contaminants in spices, 1973–2010

This review identified fourteen reported illness outbreaks attributed to consumption of pathogen-contaminated spice during the period 1973–2010. Countries reporting outbreaks included Canada, Denmark, England and Wales, France, Germany, New Zealand, Norway, Serbia, and the United States. Together, these outbreaks resulted in 1946 reported human illnesses, 128 hospitalizations and two deaths. Infants/children were the primary population segments impacted by 36% (5/14) of spice-attributed outbreaks. Four outbreaks were associated with multiple organisms. Salmonella enterica subspecies enterica was identified as the causative agent in 71% (10/14) of outbreaks, accounting for 87% of reported illnesses. Bacillus spp. was identified as the causative agent in 29% (4/10) of outbreaks, accounting for 13% of illnesses. 71% (10/14) of outbreaks were associated with spices classified as fruits or seeds of the source plant. Consumption of ready-to-eat foods prepared with spices applied after the final food manufacturing pathogen reduction step accounted for 70% of illnesses. Pathogen growth in spiced food is suspected to have played a role in some outbreaks, but it was not likely a contributing factor in three of the larger Salmonella outbreaks, which involved low-moisture foods. Root causes of spice contamination included contributions from both early and late stages of the farm-to-table continuum.     

Children's reluctance to seek help with schoolwork.

Elementary-school children were asked why they do, or do not, ask for help from parents, teachers, and classmates when they have problems in math and reading. Responses were correlated with achievement scores. Findings indicate: (a) Classmates are seen as less helpful than adults in answering questions, (b) there is more concern about possible negative reactions (i.e., perceptions of being "dumb") from classmates than from adults, (c) children perceive a greater need for help in math than in reading, (d) girls are more concerned than boys about negative reactions to help-seeking in math, (e) the more children believe that asking questions is likely to help in learning, the more they like to ask questions, and (f) the lower the child's achievement, the greater their reluctance to ask questions. Discussion focuses on ways in which children's attitudes differ according to academic subject and identity of the helper. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Task demand and cardiovascular response magnitude: Further evidence of the mediating role of success importance.

The interactive effects of success importance and task demand on cardiovascular reactivity were investigated in 2 experiments. In Exp 1, Ss learned that success on an easy or difficult memory task would allow them to avoid a mild or severe noise. As expected, pretask and task elevations in heart rate and systolic blood pressure increased with difficulty only when the noise was to be severe. In Exp 2, Ss listened to a victim, attending either to how she must feel or to technical features of the presentation. Then they were given the chance to earn a donation by succeeding on an easy or difficult memory task. Pretask cardiovascular data accorded with predictions predicated on the assumption that the need to help would be greater among victim perspective Ss. For them, systolic elevations increased with difficulty, whereas for technical perspective Ss systolic elevations were low regardless of task demand. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Digestibility and nutritional value of crude oil from three amaranth species

Oils from a selection ofAmaranthus caudatus, A. hypochondriacus andA. cruentus were extracted with hexane. The crude oils were analyzed for acid value, saponification and iodine number, and were included in basal casein diets for rat studies at 5 and 10% levels to replace equal amounts of refined cottonseed oil. The oils fromA. cruentus andA. hypochondriacus were similar in the oil properties studied and different fromA. caudatus. At either 5 or 10% food intake levels, weight gain and PER were not statistically different from values reported for cottonseed oil. True digestibility of amaranth oil was lower than that of cottonseed oil.A. cruentus oil gave the lowest digestibility. Oil levels induced statistical differences in food intake and digestibility. Oils fromA. caudatus, A. hypochondriacus and cottonseed induced similar serum cholesterol levels, while oil fromA. cruentus gave statistically higher values. Hemoglobin, hematocrit and serum proteins were similar among all groups. Microscopic analysis of the organs of the rats revealed some changes that were also found in cottonseed oil-fed rats. It was concluded that crude amaranth oil has lower digestibility than cottonseed oil, but that it is not responsible for growth-depressing effects when the seed is fed raw as compared to processed materials.     

Phytotoxic properties of cnicin,a sesquiterpene lactone fromcentaurea maculosa (spotted knapweed)

Water and solvent extracts from the aerial tissues ofCentaurea maculosa, spotted knapweed, inhibited the root growth of lettuce. Column chromatography and lettuce bioassay of a chloroform extract led to the isolation of cnicin, a sesquiterpene lactone. Pure cnicin was bioassayed at 0, 1, 2, 4, 6, 8, and 10 mg/5 ml water with lettuce, created wheatgrass, bluebunch wheatgrass, rough fescue, western larch, lodgepole pine, and spotted knapweed. Germination was inhibited at one or more concentrations for all species except lodgepole pine and spotted knapweed. Growth, particularly of the roots, was retarded between 1 and 4 mg of cnicin. Lettuce, bluebunch wheatgrass, and spotted knapweed were inhibited significantly at all concentrations tested.