Relation between wheat-rye crossability and seed set of common wheat after pollination with other species in the Hordeae

Summary Cultivars of common wheat (Triticum aestivum L. em. Thell.) of high wheat-rye (Secale cereale L.) crossability set more seed with pollen of other related species than did wheats of low wheat-rye crossability. This was found to be true for pollen parents from the genera Triticum, Aegilops, Secale, Agropyron and Elymus.     

Antioxidant properties of chlorogenic acid and its alkyl esters in stripped corn oil in combination with phospholipids and/or water

In bulk oil, it is generally thought that hydrophilic antioxidants are more active than lipophilic antioxidants. To test this hypothesis, the antioxidant activity of phenolics with increasing hydrophobicity was evaluated in stripped corn oil using both conjugated diene and hexanal measurements. Chlorogenic acid and its butyl, dodecyl, and hexadecyl esters were used as model phenolic antioxidants with various hydrophobicities. Results showed that hydrophobicity did not correlate well with antioxidant capacity. The combination of chlorogenic acid derivatives with dioleoylphosphatidylcholine (DOPC) and/or water was also studied to determine if the physical structure in the oil affected antioxidant activity. DOPC alone made hexadecyl chlorogenate a less effective antioxidant, but it did not change the antioxidant capacity of chlorogenic acid. In contrast, the combination of DOPC and water (～400 ppm) renders chlorogenic acid a less active antioxidant, whereas it does not change the activity of hexadecyl chlorogenate. These results show, in bulk oil, that intrinsic parameters such as the hydrophobicity of lipophilized phenolics do not exert a strong influence on antioxidant capacity, but they can be highly influential if potentialized by extrinsic factors such as physical structures in the oil.     

Phosphorus Characterisation of Sludge and Crust Produced by Stabilisation Ponds in a Dairy Manure Management System

In dairy farming, recirculation and continuous use of nutrients are necessary for sustainable nutrient management in both the short- and long-term. When managed effectively, nutrient recycling can improve soil fertility. On the other hand, if applied nutrients are in excess of the soil’s nutrient holding capacity, nutrients can enter surface and ground water bodies resulting in eutrophication. Phosphorus (P) characterisation in manure, pond sludge and crust, in terms of plant availability, is the first step to sustainably manage nutrients within dairy farms. In this study, pond sludge and crust were characterised for P using a sequential fractionation method. Pond sludge and crust contained significant amounts of labile P. Water extractable P (H₂O-P) in primary anaerobic pond and secondary facultative pond sludges was found to be about 8 to 13 times higher than the amount found in the surface soil (0–10 cm) of a grazing paddock. Similarly, sodium bicarbonate extractable P (NaHCO₃-P) in the two types of sludges was found to be about 6 times higher than in the soil. The relatively higher labile P (H₂O-P and NaHCO₃-P) in sludge compared to soil indicates that the sludge can be utilised as a P fertilizer on grazing pasture. In contrast, lower H₂O-P compared to that of raw manure indicates that the use of sludge and crust instead of raw manure can reduce the possibility of P loss by surface runoff and leaching. Hence, it is preferable to use pond sludge and crust as fertiliser instead of raw manure.     

Increasing the oxidative stability of liquid and dried tuna oil-in-water emulsions with electrostatic layer-by-layer deposition technology

Omega-3 Fatty acids have numerous health benefits, but their addition to foods is limited by oxidative rancidity. Engineering the interfacial membrane of oil-in-water emulsion droplets to produce a cationic and/or thick interface is an effective method to control lipid oxidation. Cationic and thick emulsion droplet interfacial membranes can be produced by an electrostatic layer-by-layer deposition technique resulting in droplets that are coated by multiple layers of emulsifiers. Tuna oil-in-water emulsion droplets coated by lecithin and chitosan produce cationic emulsion droplets that are more oxidatively stable than emulsions coated by lecithin alone. Ethylenediaminetetraacetic acid (EDTA) was able to increase the oxidative stability of emulsions stabilized with lecithin and chitosan more effectively than mixed tocopherols. The combination of EDTA and mixed tocopherols was not more effective than EDTA alone suggesting that control of prooxidant metals was the most important antioxidant technology. The production of emulsion droplets coated with lecithin and chitosan could be an excellent technology for stabilization of oxidatively unstable lipids for use in a variety of food products.     

Composition and Antimicrobial Activity of Anemopsis californica leaf oil

Isolation and characterization of leaf volatiles in Anemopsis californica (Nutt.) Hook. and Arn. (A. californica) was performed using steam distillation, solid-phase microextraction, and supercritical fluid extraction. Thirty-eight compounds were detected and identified by gas chromatography; elemicin was the major component of the leaf volatiles. While the composition of the leaf volatiles varied with method of extraction, alpha-pinene, sabinene, beta-phellandrene, 1,8-cineole, piperitone, methyl eugenol, (E)-caryophyllene, and elemicin were usually present in readily detectable amounts. Greenhouse-reared clones of a wild population of A. californica had an identical leaf volatile composition with the parent plants. Steam-distilled oil had antimicrobial properties against 3 (Staphylococcus aureus, Streptococcus pneumoniae, and Geotrichim candidum) of 11 microbial species tested. Some of this bioactivity could be accounted for by the alpha-pinene in the oil.     

Antioxidant activity of cysteine, tryptophan, and methionine residues in continuous phase beta-lactoglobulin in oil-in-water emulsions

Proteins dispersed in the continuous phase of oil-in-water emulsions are capable of inhibiting lipid oxidation reactions. The antioxidant activity of these proteins is thought to encompass both free radical scavenging by amino acid residues and chelation of prooxidative transition metals; however, the precise mechanism by which this occurs remains unclear. In this study, the oxidative stability of cysteine, tryptophan, and methionine residues in continuous phase beta-lactoglobulin (beta-Lg) in a Brij-stabilized menhaden oil-in-water emulsion was determined. The presence of low concentrations of continuous phase beta-Lg (250 and 750 microg/mL) significantly inhibited lipid oxidation as determined by lipid hydroperoxides and thiobarbituric acid reactive substances analysis. It was observed that cysteine oxidized before tryptophan in beta-Lg, and both residues oxidized before lipid oxidation could be detected. No oxidation of the methionine residues of beta-Lg was observed despite its reported high oxidative susceptibility. It is conceivable that surface exposure of amino acid residues greatly affects their oxidation kinetics, which may explain why some residues are preferentially oxidized relative to others. Further elucidation of the mechanisms governing free radical scavenging of amino acids could lead to more effective applications of proteins as antioxidants within oil-in-water food emulsions.     

Incorporation and stabilization of omega-3 fatty acids in surimi made from cod, Gadus morhua

Surimi containing omega-3 fatty acids from algal oil was prepared by the addition of oil-in-water emulsions or bulk oil. Emulsion and bulk oil were added separately to surimi to provide approximately 500 mg of omega-3 fatty acids per serving of surimi (85 g). Addition of the emulsion had no effect on surimi gel strength, whereas bulk oil decreased gel strength an average of 31%. All surimi treatments containing algal oil increased in Hunter b values due to the presence of carotenoids in the oil. Among cryoprotectants, sodium tripolyphosphate was the major surimi additive responsible for retarding the formation of lipid hydroperoxides and thiobarbituric acid reactive substances (TBARS). Lipid hydroperoxide and TBARS formation was lower in surimi containing bulk oil compared to surimi with emulsified oil. Both EDTA and lipid soluble antioxidants were able to decrease lipid oxidation in surimi fortified with omega-3 fatty acids. This suggests that surimi containing nutritionally beneficial omega-3 fatty acids could be developed with good oxidative stability and gel strength.     

Interactions of a cationic antimicrobial (ε-polylysine) with an anionic biopolymer (pectin): an isothermal titration calorimetry, microelectrophoresis, and turbidity study

ε-Polylysine (ε-PL) is a food-grade cationic antimicrobial that is highly effective against a range of food pathogens and spoilage organisms. In compositionally complex environments, like those found in most foods and beverages, the antimicrobial activity of cationic ε-PL is likely to be impacted by its interactions with anionic components. The purpose of this study was to characterize the interactions between cationic ε-polylysine and an anionic biopolymer (high methoxyl pectin, HMP) using isothermal titration calorimetry (ITC), microelectrophoresis (ME), and turbidity measurements. ITC and ME measurements indicated that ε-PL bound to pectin, while turbidity measurements indicated that the complexes formed could be either soluble or insoluble depending on solution composition. Ionic strength and pH were also shown to affect the interactions significantly, highlighting their electrostatic origin. This study demonstrates that ε-PL can form either soluble or insoluble complexes with anionic biopolymers depending on the composition of the system. Our study provides basic knowledge that will facilitate the more rational application of ε-PL in complex food systems.     

Stability of spray-dried tuna oil emulsions encapsulated with two-layered interfacial membranes

omega-3 Fatty acids have numerous health benefits, but their addition to foods is limited by oxidative rancidity. Spray-drying tuna oil-in-water emulsion droplets with a coating of lecithin and chitosan multilayer system could produce emulsion droplet interfacial membranes that are cationic and thick, both factors that can help control lipid oxidation. Physicochemical and oxidative stability of the spray-dried emulsions were determined as a function of storage temperature and relative humidity (RH). The combination of ethylenediaminetetraacetic acid (EDTA) and mixed tocopherols was able to increase the oxidative stability of dried emulsions. Lipid oxidation was more rapid during storage at low relative humidity (11% and 33% compared to 52% RH). At high moisture, physical modifications in the sample were observed, including reduced dispersibility and formation of brown pigments. Sugar crystallization or Maillard products produced at the higher humidities may have inhibited oxidation. Overall, spray-dried tuna oil-in-water emulsions stabilized by lecithin-chitosan membranes were more oxidatively stable than bulk oils and thus have excellent potential as an omega-3 fatty acid ingredient for functional foods.     

麦长管蚜全纯人工饲料的研究

 用双层石蜡膜 ( Parafilm‘M’)夹营养液的方法饲养麦长管蚜。经系统分析小麦植株的营养成分和反复实验 ,确定麦蚜全纯人工饲料配方 ,营养液的适宜 p H值为 6.0 ,适宜糖浓度为 2 5%。对所选的基础饲料配方的氨基酸和维生素单一缺失实验结果表明 ,麦长管蚜必需的营养物质中包括 9种氨基酸和 8种维生素 ,非必需营养组分包括 6种氨基酸及泛酸钙和肌醇等 2种维生素 ,此外 7种氨基酸以及核黄素为非营养组分或有害组分。通过全部剔除非营养组分后得到的纯人工饲料饲养的结果表明 ,麦长管蚜饲养的结果很好 ,其存活率及繁殖力与感蚜麦苗上的差异不显著 ,而且可连续饲养 2代。