Effect of grape processing on selected antioxidant phenolics in red wine

Wine, particularly red wine, is an important source of polyphenols and several studies have shown that moderate wine consumption is associated with a reduced risk of coronary heart disease. It has been hypothesized that these antioxidant compounds may be responsible for the potential beneficial effects of wine. The influence of different vinification techniques (fermentation on skin [A], mash heating [B], and the combination of both [C]) on the antioxidant capacity and the phenolic composition of red wines (Spätburgunder [Pinot Noir], Lemberger, and Cabernet Franc) were tested in the present study. The highest concentrations of anthocyanins, flavan-3-ols, flavonols, stilbenes, and antioxidant capacity were found in the red wines which were produced under the conditions of C, followed by B and A.     

Effect of ultraviolet processing on selected properties of egg white

The effect of ultraviolet processing (10.6 and 63.7 kJ m(-2)) on selected properties of egg white (absorbance, particle size, protein fractions, free sulfhydryl content, immunoreactivity, viscosity, gelling and foaming properties) was investigated. Ultraviolet exposure induced the development of browning, the formation of large protein aggregates by disulfide exchange, and protein backbone cleavage. However, egg white proteins were differently sensitive to UV radiation. No changes in immunoreactivity, gelling temperature and gel firmness were observed. Independently on the UV dose, light treated egg white produced foams with higher stability. This effect was attributed to protein aggregates jamming in the fluid interstices between bubbles and/or to the higher viscosity of the aqueous phase. The latter was also associated to higher foam volume.     

不同工艺条件对保鲜大久保桃罐藏制品风味的影响

研究了经MA贮藏的大久保桃在不同贮藏期出库后,在罐藏加工过程中不同工艺条件对制品风味的影响。试验结果表明,罐藏大久保桃制品的原料七成熟时采收,于0℃下采用MA贮藏25～40d;加工前升温后熟24～30h能够增强制品的桃香气;贮藏时间对桃香气有一定影响,但预煮时间、桃仁和桃仁水对增强桃香气效果均不显著。      

Meta-analysis of food processing on pesticide residues in fruits

The combining and quantifying effects of food processing on pesticide residues in fruits were analysed by a meta-analysis approach. Data were collected from many publications and used to calculate response ratios, confidence intervals and intra-assay coefficients of variation. The response ratios for washing by tap water, boiling and sun drying were 0.59, 0.71 and 0.65, respectively, indicating that they could reduce the pesticide residues effectively. Peeling and juicing, where response ratios were 0.11 and 0.14, respectively, showed they could reduce the pesticide residues to a very small extent. An increase of pesticide residues was indicated by oven drying with a response ratio of more than 1. Oven drying and sun drying indicated both a reduction and an increase at the 99.5% confidence interval. The response ratios given by a meta-analysis approach could be used as processing factors in food safety risk assessment and as a guide for consumers on how to reduce pesticides effectively in fruit.     

Effect of processing on antioxidant contents in selected dry beans (Phaseolus spp. L.)

Dry beans are rich sources of dietary fiber and phytochemicals such as flavonoids and phenolics. In the current study, we determined the effects of two processing methods (soaking and toasting) on total phenolics, flavonoids, proanthocyanidin and antioxidant potential by 2,2-diphenyl-1-picrylhydrazyl (DPPH) activity and ferric reducing antioxidant potential (FRAP) in selected dry beans (red kidney beans (K), black-eyed peas (B), pinto beans (P) and soy beans (S)).Total phenolics (mg/g dwb) expressed as gallic acid equivalents (GAE), total flavonoids (mg/g dwb) as catechin equivalents (CE) and proanthocyanidin expressed as leucocyanidin equivalent (mg LE/g) ranged from 3.42 to 7.21, 0.61 to 0.84 and 0.51 to 3.13 in raw beans; 3.58 to 6.94, 0.19 to 0.99 and 0.43 to 3.13 in soaked beans and 4.55 to 9.52, 0.23 to1.00 and 0.20 to 3.25 in toasted beans, respectively.FRAP (μg/g) in raw, soaked and toasted dry beans ranged from 0.00097 to 0.00424 while DPPH_(T30) (%) ranged from 43.9 to 62.61.Our results indicate that processing methods (soaking and roasting) influenced total phenolic, flavonoid and antioxidant contents (DPPH, FRAP) in selected dry beans.     

软包装水果罐头工艺研究

本文提出采用耐蒸煮铝塑复合薄膜袋新型包装材料,高酸(PH<3.7)低糖(12～16％)液体保护的配方,真空包装,最低热杀菌,常压快速冷却等工艺,生产软包装水果罐头。对主要配方的构成与工艺参数如杀菌公式、封口真空度、糖液含量等进行了单因素、多因素二次旋转组合设计试验,通过电子计算机综合分析、模拟,建立数学模型,确定最佳工艺参数。     

新型甜味剂在广式凉果生产中的应用研究

探讨了新型甜味剂在广式凉果生产中的应用,提出了解决凉果甜味剂超量使用的方法:利用甜味剂之间的协同增效作用,选择合适的新型甜味剂进行复合使用,既可降低甜味剂使用量,又可获得良好的感官质量。      

Microbial survey of selected Ontario-grown fresh fruits and vegetables

Recent produce-related outbreaks have been receiving heightened media coverage, which has increased public concern toward the safety of fresh fruits and vegetables. In response, the microbial contamination of Ontario-grown fresh fruits and vegetables was evaluated by the Ontario Ministry of Agriculture, Food and Rural Affairs during the summer of 2004. Prior to this survey, information specific to the microbial contamination of Ontario-produced fruits and vegetables was limited. This nonregulatory survey had two objectives: (i) to obtain a general microbiological profile of selected fruits and vegetables produced in Ontario and (ii) to use the information and knowledge gained from this survey to direct and support future on-farm food safety research and food safety programs to manage potential risks. In all, 1,183 samples, including muskmelon (151), scallions and green onions (173), leaf lettuce (263), organic leaf lettuce (112), head lettuce (155), parsley (127), cilantro (61), and fresh market tomatoes (141), were collected and analyzed. Samples were analyzed for Salmonella, Shigella, and generic E. coli. Enrichment cultures positive for E. coli were further assessed for verotoxigenicity. One sample each of Roma tomato and organic leaf lettuce were positive for Salmonella, with no samples yielding Shigella or verotoxigenic E. coli. The E. coli prevalence was highest in parsley (13.4%), followed by organic leaf lettuce (11.6%), leaf lettuce (6.5%), scallions (6.4%), cilantro (4.9%), muskmelon (1.3%), head lettuce (0%), and fresh market tomatoes (0%). These findings, in combination with foodborne illness data, will help target those commodities that require more focused risk mitigation efforts.     

Heavy metal levels in leafy vegetables and some selected fruits

The aim of this study was to determine the levels of Cu, Zn, Fe, Pb and Cd in various fruits (tomato, cherry, grape, strawberry) and vegetables (parsley, onion, lettuce, garlic, nettle, peppermint, rocket, spinach, dill, broad bean, chard, purslane, grapevine leaves) grown in Manisa region. Flame and Graphite Furnace Atomic absorption spectrometry was used to estimate and evaluate the levels of these metals. Detected levels ranged from 0.56 to 329.7, 0.01 to 5.67, 0.26 to 30.68, 0.001 to 0.97 and 0 to 0.06 μg/g for Fe, Cu, Zn, Pb and Cd, respectively. While the highest mean levels of Cu and Zn were detected in grapevine leaves, the lowest mean levels of Fe and Pb were detected in nettle. Cd was not detected in most of the fruits and vegetables studied. The estimated daily intakes of Cu, Zn, Fe, Pb and Cd through fruits and vegetables were found to be below the maximum tolerable levels recommended by FAO/WHO. The element concentrations of fruits and vegetables analyzed in this study were within safety baseline levels for human consumption.     

Heavy metal levels in leafy vegetables and some selected fruits

The aim of this study was to determine the levels of Cu, Zn, Fe, Pb and Cd in various fruits (tomato, cherry, grape, strawberry) and vegetables (parsley, onion, lettuce, garlic, nettle, peppermint, rocket, spinach, dill, broad bean, chard, purslane, grapevine leaves) grown in Manisa region. Flame and Graphite Furnace Atomic absorption spectrometry was used to estimate and evaluate the levels of these metals. Detected levels ranged from 0.56 to 329.7, 0.01 to 5.67, 0.26 to 30.68, 0.001 to 0.97 and 0 to 0.06 μg/g for Fe, Cu, Zn, Pb and Cd, respectively. While the highest mean levels of Cu and Zn were detected in grapevine leaves, the lowest mean levels of Fe and Pb were detected in nettle. Cd was not detected in most of the fruits and vegetables studied. The estimated daily intakes of Cu, Zn, Fe, Pb and Cd through fruits and vegetables were found to be below the maximum tolerable levels recommended by FAO/WHO. The element concentrations of fruits and vegetables analyzed in this study were within safety baseline levels for human consumption.     

Effect of storage temperature on galactose formation in UHT milk

Galactose has been studied from the standpoint of its suitability as a heat-induced parameter for processed milk. Galactose content in two directly and two indirectly UHT treated liquid milk samples were studied during storage until the end of its shelf-life (12 weeks) period at temperatures of 6, 20, 30, 40, and 50°C. No significant differences during storage were found with reference to the type of thermal process applied, nor with respect to the initial galactose content of the sample. Galactose formation was just directly related to storage time and temperature, being more significant at temperatures higher than 20°C. Galactose increased slightly during storage at ambient temperature (20°C) after the first weeks but kept constant under temperature of refrigeration until end of storage. Thermal history of the processed milk, mainly at a temperature above 20°C, could affect the usefulness of galactose as a heat-induced parameter.     

21世纪初我国果蔬保鲜与加工的发展方向

<正> 耕作时,除了留意采前工序外,还要顾及采后处理,特别是对易于腐烂的果蔬类产品,笔者阐述了21世纪初我国果蔬保鲜与加工的发展方向,相信对业内人士会有所启发。 国外经验 作为借镜 农产品的保鲜和加工是农业生产的延续,是农业再生产过程中的“二产经济”,发达国家均把产后储藏加工过程放在农业的首位,如美国农业总投入中,用于采前的投入有30％,用于采后     

Effect of selected autochthonous starter cultures on processing and quality characteristics of Greek fermented sausages

Selected autochthonous starter (SAS) cultures (i.e. Lactobacillus sakei 8416, Lactobacillus sakei 4413, and L. sakei 8426, L. plantarum 7423 and L. curvatus 8427) were used as starter cultures in addition to a control treatment in the production of fermented sausages. The SAS cultures had a rapid growth and dominated the fortuitous population of LAB during the whole fermentation and ripening process improving the sensory attributes in comparison to control. Apart from the treatment produced with L. sakei 8416, all other SAS cultures prevented the lipid oxidation to values lower than 1 mg malonaldehyde/kg. The Micrococcaceae count and the redness of the sausages was not affected by the smoking and the acidification during the fermentation in the treatments produced with L. sakei 8416 and L. sakei 4413. The treatment of L. sakei 4413 had the lowest (*P < 0.05) content of all biogenic amines. In comparison to the control, the reduction of tyramine was 13%, tryptamine 55%, cadaverine 60% and putrescine 72%. Sausages produced with SAS cultures L. sakei 4413 and L. sakei 8416 had the highest scores for all sensory attributes. The results indicated that the SAS culture of L. sakei 4413 is the best autochthonous starter culture for fermented sausages.     

Study on the migration phenomena of selected metals in canned fruits during long storage

Experimental studies were conducted on the migration of Fe, Sn, Ca, and Mg in canned fruits: black currant, cherry and strawberry. Three-piece-cans had been protected with different coatings and technics. Cans of 31 capacity with fruits were stored in ambient temperature (ca 20 °C) during 60 weeks. There was stated increasing dependence of storage time on concentration of Fe and Sn in cans. Contents of Ca and Mg in this time systematically decreased in cans due to adsorption process of these metals on internal coatings. Migration rate of Fe and Sn, as well as migration trends of Ca and Mg (adsorption process) are shown on figures. There are great differences among migration of Fe, Sn and migration trends of Ca and Mg. Both these phenomena are disadvantageous for quality of canned fruits.     

Effect of permeable coatings on the storage life of fruits.

A permeable membrane coating can be produced on fruit surfaces by dipping in an aqueous dispersion of Pro-long, a mixture of sucrose esters of fatty acids and the sodium salt of carboxymethylcellulose. Mangoes (Mangifera indica L. cv. Julie) were treated with 0.75 and 1.0% w/v aqueous suspensions of Pro-long and stored at 252°C/85–95% RH. Treatment with 0.75% Pro-long significantly increased the storage life of mangoes, retarding ripening and reducing weight loss, without adversely affecting the sensory quality of the fruit. Treatment at 1% resulted in increased ethanol formation in the pulp of some mangoes.     

Reduction of pesticides residues on okra fruits by different processing treatments

For the first time, the effect of washing, water boiling, chemical boiling, steaming and cooking treatments on the reduction of residues of indoxacarb, fenarimol, acetamiprid and chlorfenapyr in okra fruits was investigated. Residues were analyzed using quick, easy, cheap, effective, rugged, and safe (QuEChERS) method combined with liquid chromatography tandem-mass spectrometry (LC–MS/MS). Our results show that some treatments could significantly decrease pesticide residues. The reduction of residues by washing treatment was not correlated to water solubility: Chlorfenapyr (non-systemic pesticide) was decreased by 90 % and acetamiprid (systemic pesticide) was removed by 48 %. Therefore, we suggest that pesticide residues were washed off by removing the loosely attached pesticides on the okra fruit surface. The time of exposure in both boiling and steaming treatments has no significant effect on reduction of pesticides residues. Additionally, cooking after the washing and boiling treatments reduced the pesticides residues. In particular, acetamiprid was reduced after the cooking treatment to 90 %.     

Effect of ultrasound processing on the bioaccessibility of phenolic compounds and antioxidant capacity of selected vegetables

Food Science and Biotechnology - Ultrasound processing can result in cell wall disruption, facilitating the release of the cellular content. Therefore, we hypothesized that sonication of vegetables...     

果蔬加工的四个新趋势

<正> 目前,我国水果和蔬菜的总产量为世界第一位。据统计,1999年我国的水果产量达到0.62亿吨,蔬菜总产量为4.10亿吨,为发展我国的农业经济作出了重要的贡献。但是随着果蔬产量的大幅度提高,卖果蔬难的问题开始出现。更糟的是,果蔬产品含水量高,容易腐烂,加上我国的果蔬深加工水平不     

果蔬肉脯的制作工艺

在传统肉脯生产基础上,配以番茄、胡萝卜、芹菜等果蔬汁,以增添肉脯的维生素含量,使肉脯既有肉的醇厚香味,又有果蔬的清香,而且卫生指标符合食品卫生要求。