西安高校蔬菜的物流与配送

随着生活节奏的加快,新鲜蔬菜以现代配送方式走进家庭是大势所趋.针对西部地区的具体情况,以高校作为蔬菜配送的起点,解决了过去蔬菜供应费时费力、蔬菜品质难以保证等一系列问题.而且,由于减少了中间环节,蔬菜成本大大降低,为购买蔬菜提供了最方便快捷的途径.     

A rapid quantitative determination of phenolic acids in Brassica oleracea by capillary zone electrophoresis

A simple and rapid capillary zone electrophoresis method to quantitatively determine the phenolic acid contents in brassica vegetables is described. Phenolic compounds were extracted from broccoli, broccolini, Brussels sprouts, cabbage and cauliflower and the main hydroxycinnamic acids (sinapic, ferulic, p-coumaric and caffeic acids) were isolated by solid phase extraction with C18 cartridges. Using an optimised method, the four analytes were separated in less than 7 min in a 50 μm × 60 cm capillary with a 15 mM borate buffer (pH = 9.13) and a separation voltage of 30 kV at 30 °C. A linear relationship was observed for the method (r = 0.9997–0.9999) with detection limits ranging from 1.1 to 2.3 mg/kg of vegetables for the analytes. This method demonstrated good reproducibility with coefficients of variation of less than 5% for peak area and less than 1% for migration time (n = 7). The method was successfully applied to quantitatively determine the phenolic acid contents in a range of brassica vegetables and the results were in good agreement when compared to those from high performance liquid chromatography analysis.     

Effect of Cooking on Soluble and Insoluble Oxalate Contents in Selected Pakistani Vegetables and Beans

The present study evaluated the effects of cooking on the total, soluble and insoluble oxalate contents in six different types of locally consumed vegetables and beans (spinach, carrots, beet root, white bean, red bean and soybean). The foods were cooked in water until they reached the soft consistency (12–15 min for vegetable and 2 h for beans). The raw and cooked samples were analyzed for their soluble and insoluble oxalate contents using the HPLC techniques. The total oxalate content of raw spinach, carrot, beet root, white bean, red bean and soybean, were found to be 978 ± 5, 49 ± 7, 67 ± 12, 158 ± 16, 113 ± 15, and 497 ± 22 mg/100 g of fresh weight respectively. The total oxalate contents of these foods after boiling were 477 ± 8, 16 ± 9, 52 ± 14, 47 ± 17, 72 ± 17, and 224 ± 25 mg/100 g of fresh weight respectively. The results showed that boiling significantly (P < 0.05) reduced both soluble and insoluble oxalate contents. More losses were observed in the soluble than the insoluble oxalates. The reduction in soluble oxalate in different vegetables ranged from 16 to 66% whereas in beans ranged from 40 to 77%. The data suggests that the use of boiled vegetables can be an effective strategy for reducing the dietary intake of oxalates in individuals predisposed to the development of kidney stones.     

Combination of microbubbles with oxidizing sanitizers to eliminate Escherichia coli and Salmonella Typhimurium on Thai leafy vegetables

Microbubbles (MB) technology was applied in a washing process a few studies have been done with food materials, particularly to reduce the microbial contamination on leafy vegetables. This study determined the effectiveness of MB (Ø ∼ 50–70 μm) combined with three sanitizers acidic electrolyte water (AEO, 20 and 40 mg/L, ORP 910–1010 mV, pH 2.7–3.1), chlorine dioxide (ClO_2, 3 and 5 mg/L, ORP 550–680 mV, pH 7.1–7.5), and sodium hypochlorite (NaOCl, 40 and 80 mg/L, ORP 900–990 mV, pH 6.5–6.7) in order to inactivate Escherichia coli and Salmonella Typhimurium on artificially contaminated sweet basil (Ocimum basilicum Linh) and Thai mint (Mentha cordifolia Opiz.). Although air MB alone did not possess antimicrobial activity, washing with MB combined with the two oxidizing sanitizers (NaOCl and AEO) for 5 min resulted in an effective reduction in S. Typhimurium and E. coli on sweet basil and Thai mint with 2–3 log reductions (99.2–99.8%). Washing vegetables with MB and NaOCl at a concentration of free chlorine of 40 mg/L NaOCl or 20 mg/L AEO yielded the best results in killing S. Typhimurium with 1.21–1.90 and 0.67–2.25 log reductions, respectively. In addition, the reduction of E. coli and S. Typhimurium on sweet basil appeared to be higher than on Thai mint. Differences in surface roughness may assist the bubbles and sanitizers to detach bacterial cells and therefore increase the washing efficacy. Furthermore, applying sanitizers in washing solution was a powerful means of killing planktonic E. coli and S. Typhimurium in the wash water and preventing cross-contamination in the washing process.     

Pork in good company? Exploratory analysis of side dishes,beverages, foodscapes and individual characteristics

The objective of this study is to explore the association between pork as the main meal component and the choice for side dishes and beverages depending on foodscape and individual characteristics, including overweight and obesity among fresh pork consumers (n = 2156) in five European countries (Belgium, Denmark, Germany, Greece and Poland). Males were found to combine pork more with caloric drinking (odds ratio = 1.32) and low levels of vegetable intake (odds ratio = 1.32) compared to females. Younger consumers were more likely to combine pork with low levels of vegetable intake but less likely to combine pork with sauces or condiments. Heavy users of pork were more likely (odds ratio = 1.43) to combine pork with sauces or condiments. The study also found an association between being overweight or obese and higher consumption of carbohydrate rich staple foods (odds ratio = 1.30) and caloric drinks (odds ratio = 1.30) as side dishes to pork meat. Substantial cross-cultural differences were revealed in line with typical pork consumption and meal composition habits in the respective countries. Finally, this study found that the company of family plays a significant role when choosing side dishes for pork as meal center, thus constituting a relevant venue for the positioning and marketing of pork, as well as for future public health information about meals with pork as main meal component.     

Stable isotope ratio and elemental composition parameters in combination with discriminant analysis classification model to assign country of origin to commercial vegetables – A preliminary study

Recently, increased public attention has been paid to the geographical authentication of food, including vegetables, which are considered to be one of the major health-promoting components in a balanced diet. The purpose of the present study was to investigate the suitability of the use of isotopic compositions of light elements (δ¹³C, δ¹⁵N, δ¹⁸O, δ³⁴S) in combination with multi-elemental fingerprinting (P, S, Cl, K, Ca, Mn, Fe, Zn, Br, Rb, Sr) to provide rapid, robust and inexpensive screening methods for distinguishing lettuce, sweet pepper, and tomato samples according to their given country of origin (i.e., Slovenia, Austria, Spain, Morocco, Italy, Greece), and thus ensuring their traceability in terms of their authenticity. The classification efficiency of the proposed multivariate statistical models using supervised pattern-recognition analysis, namely multivariate discriminant analysis, was sufficient for rapid and robust screening purpose. The predictions of the suggested discriminant analysis models per kind using cross-validation leave-one-out were 86.2%, 71.1% and 74.4% for lettuce, sweet pepper and tomato, respectively. The first use of the proposed methodology on vegetable samples on European and Mediterranean scales provides a valuable and necessary contribution to the development and implementation of a new national surveillance system that can be used to trace the geographical origins of vegetables.     

Determination of nonylphenol ethoxylate metabolites in vegetables and crops by high performance liquid chromatography-tandem mass spectrometry

A method has been developed for the simultaneous determination of the concentration of nonylphenol (4-NP), nonylphenol monoethoxylates (NP₁EO) and nonylphenol diethoxylates (NP₂EO) in vegetables and crops by liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS/MS). These target compounds were extracted from vegetable and crop samples with acetonitrile, and then the extracts were cleaned using solid phase extraction with graphitised carbon black tandem primary secondary amine (PSA) cartridges. The MS method enabled highly reliable identification by monitoring the corresponding ammonium adduct [M+NH₄]⁺ in the positive mode for NP₁EO and NP₂EO, and the deprotonated molecule [M−H]⁻ in the negative mode for 4-NP. Recoveries for the spiked samples ranged from 65% to 118%. The limit of detection (LOD) of 4-NP, NP₁EO and NP₂EO was 3, 5 and 0.1 μg kg⁻¹, respectively. This method would be useful for the quick and routine detection of the residues of 4-NP, NP₁EO and NP₂EO in vegetables and crops.     

Pre-sliced or do it yourself? – Determinants of schoolchildren’s acceptance of convenience fruits and vegetables

Previous research shows that the method of preparation can significantly influence children’s fruit and vegetable (F&V) acceptance. The purpose of this study was to analyze the determinants of children’s liking of industrial pre-sliced and single packed F&V within the framework of the European Union School Fruit Scheme (SFS). In addition, the influence of the liking of pre-sliced F&V on the choice for pre-sliced vs. non-pre-sliced F&V was determined. A baseline survey was conducted with 118 schoolchildren (aged 8–10 years) receiving normal F&V in the framework of the SFS and involved the preparation and characteristics of F&V. After the intervention group (n = 60) received pre-sliced F&V for 6 weeks, the survey was conducted again with complementary questions concerning pre-sliced F&V, and the results were compared with those of a control group (n = 58) that continued to receive non-pre-sliced F&V. The survey results indicated that the liking of F&V significantly decreased in the intervention group, while it remained constant in the control group. Multiple regression analyses indicated that the sensory deficits and negative packaging characteristics of pre-sliced F&V significantly and negatively influenced the rating for pre-sliced F&V, while savings in effort and time for preparation positively influenced the liking. Furthermore, the liking of pre-sliced F&V significantly and positively influenced the choice for pre-sliced F&V. In contrast, a positive attitude towards F&V preparation negatively influenced the choice of pre-sliced F&V. Based on the results, the general distribution of pre-sliced F&V cannot be recommended in the framework of school-based F&V intervention programs.     

Contamination levels of organophosphorus and synthetic pyrethroid pesticides in vegetables marketed in Accra,Ghana

A total of 155 domestic samples of vegetables were collected from local markets in Greater Accra region of the country. All samples were examined for residues of 21 pesticides, including organophosphorus and synthetic pyrethroids. Overall, 52% of the samples had detectable pesticide residues. Of the contaminated samples, 32% contained detectable residues within the MRLs and 21% exceeded their EU maximum residue limits (MRLs) adopted values. The synthetic pyrethroid pesticides recorded higher amount of violation compared with organophosphorus. The most frequently violated pesticides were allethrin and chlorpyrifos at 21% and 14% of violated samples analyzed respectively, which can be an indication of bleach of GAPs for use of these pesticides.     

Organics unpacked: The influence of packaging on the choice for organic fruits and vegetables

In many supermarkets throughout Europe, it has become common practice in the fruit and vegetable department to offer options in plastic packaging. Recent trends, however, move towards the removal of packaging. The current study examines whether offering fruit and vegetables without primary packaging increases the likelihood that consumers choose these products. This is especially relevant for organic fruit and vegetables, given that plastic may be perceived as contrary to the sustainable nature of these products. A first experiment, using a student sample and an immersive 3D virtual supermarket environment, shows that choice for organic fruit and vegetables indeed increases when organics are offered without packaging. A second experiment with the virtual supermarket generalizes these findings to a sample of supermarket patrons, additionally showing that unpacked fruit and vegetables are preferred over packed options overall, both for organic and non-organic products. We conclude that removing the primary packaging of organic fruit and vegetables appears to be a promising intervention in attempts to increase organic sales.