Improved selection against the purple colour defect of cauliflower curds

Summary Purple colourations of the cauliflower curd detract from the commercial value of the crop. Curds were found to develop purple colourations when in aseptic nutrient culture, and this was correlated with their inherent tendencies to form purple curds in the field as revealed by a progeny test. It was advocated that selection against the defect in the field should be supported by assessment in culture.     

Breeding system,taxonomy, and breeding strategy in cauliflower,Brassica oleracea var. botrytis L.)

Summary Cauliflowers representing those maturing in Britain in autumn, winter and spring were assessed for self-compatibility by self-pollen tube growth. A tendency existed for groups taking longer to mature to be more self-incompatible, but a range of incompatibilities was apparent in all groups. These results complement those of other workers.It is argued that despite demonstrable heterosis within many groups of cauliflowers, radical advances are probably best made by selecting self-compatible material from annual × biennial hybrid populations.     

Selection against the bracting defect of cauliflower

Summary The appearance of bracts through the surface of the cauliflower curd had a heritability estimate of 0.73 ± 0.10 based on the regression of progeny on parent when grown under field conditions. When curds were taken from field grown plants and aseptically cultured, their bracting characteristics were enhanced. It is advocated that a two-tier system of selection, firstly in the field and then in culture, would increase the likelihood of breeding bract free cauliflowers.Also, Department of Biological Sciences, The Polytechnic, Hatfield, Hertfordshire, UK.     

Elisa to quantify hexanal-protein adducts in a meat model system.

Monoclonal antibodies (MAb) were produced to hexanal-bovine serum albumin conjugates. An indirect competitive ELISA was developed with a detection range of 1-50 ng of hexanal/mL. Hexanal conjugated to three different proteins was recognized, whereas free hexanal and the native proteins were not detected. The antibody cross-reacted with pentanal, heptanal, and 2-trans-hexenal conjugated to chicken serum albumin (CSA) with cross-reactivities of 37.9, 76.6, and 45.0%, respectively. There was no cross-reactivity with propanal, butanal, octanal, and nonanal conjugated to CSA. The hexanal content of a meat model system was determined using MAb and polyclonal antibody-based ELISAs and compared with analysis by a dynamic headspace gas chromatographic (HS-GC) method and a thiobarbituric acid reactive substances (TBARS) assay. Both ELISAs showed strong correlations with the HS-GC and TBARS methods. ELISAs may be a fast and simple alternative to GC for monitoring lipid oxidation in meat.     

Infusion of volatile flavor compounds into low-density polyethylene

Supercritical fluids can extract components from some matrixes (e.g., fat and flavors from food) as well as infusing additives into synthetic polymer matrixes. To study the feasibility of infusing flavors into matrixes as a potential flavoring mechanism, a wide range of volatile flavor compounds was infused into a well-defined synthetic polymer (low-density polyethylene) using supercritical carbon dioxide. The polymer was then extracted, and the amount of infused compound was determined. The effects of time, temperature, pressure, rate of depressurization, volatile concentration, and volatile properties on the degree of infusion were studied. Infusion with supercritical carbon dioxide achieved much higher loadings of the polymer (0.01 to 6.87 mg/g LDPE, depending on the volatile molecule being infused) compared to those achieved by static diffusion. Forty-five volatiles were infused, from which a model was developed to predict infusion as a function of certain physicochemical properties.     

Plasma Progesterone Profile in Ovariectomized Beef Cows after Intra-vaginal Insertion of New, Once-used or Twice-used CIDR

Objective of this study was to show plasma progesterone concentrations in ovariectomized beef cows after treatment with new, once-used and twice-used controlled internal drug-releasing devices (CIDRs). Four ovariectomized beef cows were used for the experiment. Plasma concentrations of progesterone were quantified using a validated ELISA. The CIDR was inserted into vagina of cows by using a standard CIDR applicator and then removed 7 days after insertion. One week later, once-used CIDR was inserted and removed on day 7. Twice-used CIDR was, then inserted at an interval of 7 days. Mean plasma concentrations of progesterone 24 h after new CIDR insertion was 4.0 ± 0.1 ng/ml, which thereafter decreased gradually to 1.4 ± 0.1 ng/ml at day 7. In cows treated with once-used CIDR or twice-used CIDR, mean plasma progesterone concentrations at day 1 were 2.4 ± 0.2 or 1.8 ± 0.2 ng/ml and 1.0 ± 0 or 0.9 ± 0.1 ng/ml at day 7 respectively. The results suggest that once-used CIDR may be still effective to produce luteal phase progesterone concentrations in plasma in non-suckling beef cows.     

The impact of a community-based food skills intervention on cooking confidence, food preparation methods and dietary choices - an exploratory trial

OBJECTIVE: To evaluate the feasibility of undertaking a food skills intervention study in areas of social deprivation aimed at altering cooking confidence, food preparation methods and dietary choices. DESIGN: A standardised skills programme was implemented in community-based settings. Pre- (T1) and post-intervention (T2) and 6-month follow-up (T3) measures (7-day diaries and self-administered questionnaires) were undertaken in intervention and comparison groups. SETTING: Eight urban communities in Scotland. SUBJECTS: One hundred and thirteen adults living in areas of social deprivation. RESULTS: It was clear that many subjects led fragmented lives and found commitment to intervention classes problematic. Sixty-three subjects completed the final (T3) assessments. The response to each component varied due to inability to attend sessions, illness, study requirements, employment, moving out of the area, change in circumstances, loss of interest and loss of postal questionnaires. At baseline, reported consumption of fruit and vegetables was low (mean frequency 8.1 +/- 4.78 times per week). Fruit intake increased significantly (P < 0.05) between T1 and T2 in the intervention group (1.7 +/- 2.36 to 2.7 +/- 3.28 times per week) only. Between T1 and T3, there was a significant increase (P < 0.05) in intervention subjects who reported confidence in following a recipe (67-90%,). CONCLUSIONS: This exploratory trial shows that a food skills intervention is likely to have a small but positive effect on food choice and confidence in food preparation. A full-scale randomised controlled trial in this hard-to-reach group would require a range of flexible approaches rather than a fully defined intervention, and presents challenges for trial design.     

Extraction and characterization of oil bodies from soy beans: a natural source of pre-emulsified soybean oil

Soybeans contain oil bodies that are coated by a layer of oleosin proteins. In nature, this protein coating protects the oil bodies from environmental stresses and may be utilized by food manufacturers for the same purpose. In this study, oil bodies were extracted from soybean using an aqueous extraction method that involved blending, dispersion (pH 8.6), filtration, and centrifugation steps. The influence of NaCl (0-250 mM), thermal processing (30-90 degrees C, 20 min) and pH (2-8) on the properties and stability of the oil bodies was analyzed using zeta-potential, particle size, and creaming stability measurements. The extracted oil bodies were relatively small ( d 32 approximately 250 nm), and their zeta-potential went from around +12 mV to -20 mV as the pH was increased from 2 to 8, with an isoelectric point around pH 4. The oil bodies were stable to aggregation and creaming at low (pH = 2) and high (pH >/= 6) pH values but were unstable at intermediate values (3 相似文献   

Development of an immunological technique for estimating mycelial biomass of Mycena galopus in leaf litter

Antisera were produced in rabbits against cell wall and cytoplasmic components of the mycelium of a litter-decomposing basidiomycete, Mycena galopus (Pers. ex Fr.) Kummer. The antisera were conjugated with fluorescein isothiocyanate, and positive reactions were obtained in direct and indirect fluorescent antibody (FA) tests with homologous antigens and with heterologous antigens of M. galopus from pure cultures and field material. Cross reactions occurred with fungal associates of M. galopus on Quercus litter from a deciduous woodland, but these were mostly removed by absorption with a preparation of Cladosporium herbarum Link ex Fr. Membrane filtration combined with FA staining and rhodamine-gelatin counter-staining was found to be a feasible means of estimating the biomass of FA-reactive mycelium of M. galopus in leaf litter.