Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “APPLES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 685 records · Page 38Linked to original sources
PubMed1998

Evaluating survival of Escherichia coli O157:H7 in frozen and thawed apple cider: potential use of a hydrophobic grid membrane filter-SD-39 agar method.

To determine the susceptibility of Escherichia coli O157:H7 to freezing and thawing in apple cider, methods that recover injured cells are needed for accurate enumeration. This study compared the ISO-GRID hydrophobic grid membrane filter (HGMF) SD-39 agar method to two other methods: a reference most probable number (MPN) method, and plating on sorbitol MacConkey agar (SMA). To determine numbers of injured cells, SMA spread plating was also compared to Trypticase soy agar (TSA) spread plating. Two strains of E. coli O157:H7 QA 326 and ATCC 43895, were inoculated into presterilized apple cider (10 ml) which was then frozen (-20 degrees C for 24 h). Samples were thawed at 4 degrees C for 4 h, or at 23 degrees C for 1.5 h, or in a microwave oven (700 W for 10 s). Substantial cell death (0.69- to 6.33 log10 CFU/ml decreases) and injury (0.70- to 2.38-log10 CFU/ml decreases) occurred during freezing and thawing. The extent of death and injury varied with strain and thawing method. The TSA spread plating method recovered the most cells while the HGMF method always recovered more viable cells than the reference MPN method and also either recovered significantly more (P < 0.05) cells or a not significantly different number of cells than SMA spread plating. Some injured cells of both strains were not counted by the HGMF method. Significant numbers of cells injured by freezing and thawing at 4 degrees C in apple cider were enumerated in the cider was diluted 1:2 Trypticase soy broth immediately before plating. Two epifluorescent microscopic methods showed that injury was not associated with loss of cell membrane integrity.

Agar↗
PubMed1999

Inactivation of Escherichia coli O157:H7 and Escherichia coli 8739 in apple juice by pulsed electric fields.

The effect of high voltage pulsed electric field (PEF) treatment on Escherichia coli O157:H7 and generic E. coli 8739 in apple juice was investigated. Fresh apple juice samples inoculated with E. coli O157:H7 and E. coli 8739 were treated by PEF with selected parameters including electric field strength, treatment time, and treatment temperature. Samples were exposed to bipolar pulses with electric field strengths of 30, 26, 22, and 18 kV/cm and total treatment times of 172, 144, 115, and 86 micros. A 5-log reduction in both cultures was determined by a standard nonselective medium spread plate laboratory procedure. Treatment temperature was kept below 35 degrees C. Results showed no difference in the sensitivities of E. coli O157:H7 and E. coli 8739 against PEF treatment. PEF is a promising technology for the inactivation of E. coli O157:H7 and E. coli 8739 in apple juice.

Beverages↗
PubMed2000

Heat inactivation of Escherichia coli O157:H7 in apple cider containing malic acid, sodium benzoate, and potassium sorbate.

The effect of pH modification and preservative addition in apple cider on the heat resistance of Escherichia coli O157:H7 was investigated. E. coli O157:H7 and various amounts of potassium sorbate (0 to 0.2%), sodium benzoate (0 to 0.2%), and malic acid (0 to 1%) were added to apple cider. Thermal inactivation experiments were performed at 47, 50, and 53 degrees C, and D- and z-values were calculated. In apple cider without additives, the D-value at 50 degrees C (D50) was about 65 min, but addition of preservatives and malic acid significantly (P < 0.01) decreased D-values. D50-values decreased to 13.9 min in cider with 0.5% malic acid, 13.2 min with 0.1% sorbate, and 7.0 min with 0.1% benzoate added. Addition of both sorbate and malic acid had similar effects as either one alone, thus additive effects were not present. However, addition of both 0.2% benzoate and 1% malic acid did show additive effects, lowering D50 to 0.3 min. Addition of all three components (0.2% sorbate, 0.2% benzoate, and 1% malic acid) resulted in a D50 = 18 s. The z-value of cider without additives was about 6 degrees C, whereas z-values of cider containing malic acid, benzoate, and/or sorbate ranged from about 6 degrees C to 26 degrees C. This increase may result in a longer 5-log reduction time at higher temperatures (i.e., 70 degrees C) in cider with benzoate as compared to cider without additives.

Animals↗
PubMed2001

Reduction in levels of Escherichia coli O157:H7 in apple cider by pulsed electric fields.

Many studies have demonstrated that high voltage pulsed electric field (PEF) treatment has lethal effects on microorganisms including Escherichia coli O157:H7; however, the survival of this pathogen through the PEF treatment is not fully understood. Fresh apple cider samples inoculated with E. coli O157:H7 strain EC920026 were treated with 10, 20, and 30 instant charge reversal pulses at electric field strengths of 60, 70, and 80 kV/cm, at 20, 30, and 42 degrees C. To accurately evaluate the lethality of apple cider processing steps, counts were determined on tryptic soy agar (TSA) and sorbitol MacConkey agar (SMA) to estimate the number of injured and uninjured E. coli O157:H7 cells after PEF treatment. Cell death increased significantly with increased temperatures and electric field strengths. A maximum of 5.35-log10 CFU/ml (P < 0.05) reduction in cell population was achieved in samples treated with 30 pulses and 80 kV/cm at 42 degrees C. Cell injury measured by the difference between TSA and SMA counts was found to be insignificant (P > 0.05). Under extreme conditions, a 5.91-log10 CFU/ml reduction in cell population was accomplished when treating samples with 10 pulses and 90 kV/cm at 42 degrees C. PEF treatment, when combined with the addition of cinnamon or nisin, triggered cell death, resulting in a reduction in E. coli O157:H7 count of 6 to 8 log10 CFU/ml. Overall, the combination of PEF and heat treatment was demonstrated to be an effective pasteurization technique by sufficiently reducing the number of viable E. coli O157:H7 cells in fresh apple cider to meet U.S. Federal Drug Administration recommendations.

Beverages↗
PubMed2002

Osmotic dehydration of apple slices with CaCl2 and sucrose limits decay caused by Penicillium expansum, Colletotrichum acutatum, and Botrytis cinerea and does not promote Listeria monocytogenes or total aerobic population growth.

The interaction of Penicillium expansum Link, Colletotrichum acutatum, and Botrytis cinerea Pers.:Fr. with Listeria monocytogenes on osmotically dehydrated apple slices was evaluated. In mineral analyses of the slices, the calcium content of the peel and flesh tissues increased by 4- and 11-fold, respectively, when processed in 2% CaCl2. These slices also exhibited less decay by P. expansum, C. acutatum, and B. cinerea. Inoculation of slices with P. expansum resulted in a decrease in the pH of the flesh tissue at the infection site, while the pHs of slices infected with C. acutatum and B. cinerea increased and remained stable, respectively. Total mold population increased in wounds inoculated with P. expansum or C. acutatum. The presence of L. monocytogenes in the wounds did not significantly affect mold growth. The association of P. expansum and L. monocytogenes on apple slices resulted in a decrease in the bacterial population, whereas L. monocytogenes survived when slices were inoculated with C. acutatum. When associated with B. cinerea, there was a fourfold decrease in the L. monocytogenes population when slices were treated with 2% CaCl2. The total aerobic population was not significantly affected by the type of microorganism added to the wounds or by the osmotic treatment. These data show that osmotic dehydration with 2% CaCl2 combined with 20% sucrose limits decay of apple slices and does not promote bacterial or total aerobic population growth.

Calcium Chloride↗
PubMed2002

Addition of fumaric acid and sodium benzoate as an alternative method to achieve a 5-log reduction of Escherichia coli O157:H7 populations in apple cider.

A study was conducted to develop a preservative treatment capable of the Food and Drug Administration-mandated 5-log reduction of Escherichia coli O157:H7 populations in apple cider. Unpreserved apple cider was treated with generally recognized as safe acidulants and preservatives before inoculation with E. coli O157:H7 in test tubes and subjected to mild heat treatments (25, 35, and 45 degrees C) followed by refrigerated storage (4 degrees C). Fumaric acid had significant (P < 0.05) bactericidal effect when added to cider at 0.10% (wt/vol) and adjusted to pH 3.3, but citric and malic acid had no effect. Strong linear correlation (R2 = 0.96) between increasing undissociated fumaric acid concentrations and increasing log reductions of E. coli O157:H7 in apple cider indicated the undissociated acid to be the bactericidal form. The treatment that achieved the 5-log reduction in three commercial ciders was the addition of fumaric acid (0.15%, wt/vol) and sodium benzoate (0.05%, wt/vol) followed by holding at 25 degrees C for 6 h before 24 h of refrigeration at 4 degrees C. Subsequent experiments revealed that the same preservatives added to cider in flasks resulted in a more than 5-log reduction in less than 5 and 2 h when held at 25 and 35 degrees C, respectively. The treatment also significantly (P < 0.05) reduced total aerobic counts in commercial ciders to populations less than those of pasteurized and raw ciders from the same source (after 5 and 21 days of refrigerated storage at 4 degrees C, respectively). Sensory evaluation of the same ciders revealed that consumers found the preservative-treated cider to be acceptable.

Anticarcinogenic Agents↗
PubMed2002

Efficacy of sanitation and cleaning methods in a small apple cider mill.

The efficacy of cleaning and sanitation in a small apple cider processing plant was evaluated by surface swab methods as well as microbiological examination of incoming raw ingredients and of the final product. Surface swabs revealed that hard-to-clean areas such as apple mills or tubing for pomace and juice transfer may continue to harbor contaminants even after cleaning and sanitation. Use of poor quality ingredients and poor sanitation led to an increase of approximately 2 logs in aerobic plate counts of the final product. Reuse of uncleaned press cloths contributed to increased microbiological counts in the finished juice. Finally, using apples inoculated with Escherichia coli K-12 in the plant resulted in an established population within the plant that was not removed during normal cleaning and sanitation. The data presented in this study suggest that current sanitary practices within a typical small cider facility are insufficient to remove potential pathogens.

Anti-Bacterial Agents↗
PubMed2003

Inactivation of Salmonella during drying and storage of apple slices treated with acidic or sodium metabisulfite solutions.

This study was undertaken to determine whether pretreating inoculated Gala apple slices with metabisulfite or acidic solutions enhanced the inactivation of Salmonella during dehydration and storage. Apple slices inoculated with a five-strain mixture of Salmonella (7.6 log CFU/g) were pretreated, dried for 6 h at 60 degrees C, and stored aerobically at 25 degrees C for 28 days. Predrying treatments included (i) no treatment, (ii) 10 min of immersion in sterile water, (iii) 10 min of immersion in a 4.18% sodium metabisulfite solution, (iv) 10 min of immersion in a 3.40% ascorbic acid solution, and (v) 10 min of immersion in a 0.21% citric acid solution. Samples were plated on tryptic soy agar with 0.1% pyruvate (TSAP), brilliant green sulfa (BGS) agar, and xylose lysine tergitol 4 (XLT4) agar for the enumeration of bacteria. Populations were not significantly (P > 0.05) reduced by immersion in water but were reduced by 0.7 to 1.1 log CFU/g by immersion in acidic solutions. Immersion in the sodium metabisulfite solution reduced populations by 0.4, 1.3, and 5.4 log CFU/g on TSAP, BGS agar, and XLT4 agar, respectively. After 6 h of dehydration at 60 degrees C, populations on untreated and water-treated slices were reduced by 2.7 to 2.8, 2.7 to 2.9, and 4.0 to 4.2 log CFU/g as determined with TSAP, BGS agar, and XLT4 agar, respectively. In contrast, populations on slices treated with sodium metabisulfite, ascorbic acid, and citric acid were reduced after 6 h of dehydration by 4.3, 5.2, and 3.8 log CFU/g, respectively, as determined with TSAP; by 4.7, 5.5, and 3.9 log CFU/g, respectively, as determined with BGS agar; and by 5.5, 5.7, and 5.6 log CFU/g, respectively, as determined with XLT4 agar. Bacteria were still detectable by direct plating after 28 days except on slices treated with ascorbic acid. Immersion in metabisulfite or acidic solutions prior to dehydration should enhance the inactivation of Salmonella during the dehydration and storage of Gala apple slices.

Ascorbic Acid↗
PubMed2004

Inactivation of Salmonella typhimurium and Escherichia coli O157:H7 in apple juice by a combination of nisin and cinnamon.

Pasteurized apple juice with nisin (0, 25, 50, 100, and 200 ppm, wt/vol) and cinnamon (0 and 0.3%, wt/vol) was inoculated with Salmonella Typhimurium and Escherichia coli O157:H7 at 10(4) CFU/ml and stored at 5 and 20 degrees C. Counts on tryptic soy agar (TSA), selective medium (xylose Lysine desoxycholate agar for Salmonella Typhimurium, and MacConkey sorbitol agar for E. coli O157:H7), and thin agar layer (TAL) were determined at 1 h and 1, 3, 7, and 14 days. The TAL method (selective medium overlaid with TSA) was used for recovery of sublethally injured cells. The pathogens were gradually inactivated by the acidic pH of apple juice. Nisin and cinnamon greatly contributed to the inactivation. The killing effect was more marked at 20 degrees C, with counts in all treated samples being undetectable by direct plating in 3 days for Salmonella Typhimurium and 7 days for E. coli O157:H7. Thus, several factors influenced the decrease in counts: low pH, addition of nisin and cinnamon, and storage temperature. The TAL method was as effective as TSA in recovering injured cells of the pathogens. The combination of nisin and cinnamon accelerates death of Salmonella Typhimurium and E. coli O157:H7 in apple juice and so enhances the safety of the product.

Beverages↗
PubMed2005

Enzyme-linked immunomagnetic electrochemical detection of live Escherichia coli 0157:H7 in apple juice.

We describe the application of enzyme-linked immunomagnetic electrochemistry (ELIME) for the rapid detection of Escherichia coli O157:H7 in buffered apple juice. The ELIME technique entails sandwiching bacterial analyte between antibody-coated magnetic beads and an alkaline phosphatase-conjugated antibody. The beads (with or without bound bacteria) were localized onto the surface of magnetized graphite ink electrodes in a multiwell plate format. The enzyme substrate, 1-naphthyl phosphate, was added, and conversion of substrate to an electroactive product was measured using electrochemical detection. With this technique, detection of whole, live E. coli O157:H7 bacterial cells was achieved with a minimum detectable level of ca. 5 x 10(3) cells per ml in Tris-buffered saline or buffered apple juice in an assay time of ca. 80 min. With adjustment of pH, the ELIME response for the bacteria in either sampling medium was similar, indicating that apple juice components did not contribute to any discernible sample matrix effects.

Beverages↗
PubMed2005

Detection of patulin in apple juices marketed in the Tohoku district, Japan.

Patulin is a mycotoxin mainly produced by Penicillium and Aspergillus. We investigated the incidence of patulin contamination in 179 samples of apple juice and 9 samples of mixed juice (containing apple juice concentrate as an ingredient) commercially available in the Tohoku district of Japan. Patulin was detected in 3 of 143 samples containing domestic fruits and in 6 of 45 samples containing imported products and products produced in Japan using imported apple juice concentrate. Patulin analyses were carried out using high-pressure liquid chromatography with a detection limit of 4 microg/liter. The patulin content of contaminated domestic samples (three samples with concentrations ranging from 6 to 10 microg/liter), imported samples (one sample with a concentration of 15 microg/liter), and domestic samples produced containing imported concentrate (five samples with concentrations ranging from 6 to 9 microg/liter) was lower than the maximum limit of 50 microg/liter currently adopted by many countries, including Japan.

Beverages↗
PubMed2006

Destruction of Escherichia coli O157:H7 by vanillic acid in unpasteurized juice from six apple cultivars.

The behavior of Escherichia coli O157:H7 in Granny Smith, Gala, Empire, McIntosh, Red Delicious, and Golden Delicious apple juice with or without supplementation with 5 or 10 mM vanillic acid was examined over a storage period of 7 days at 4 and 15 degrees C. The consequences of supplementation on sensory difference and preference were also determined by triangle testing. Juices made from the six apple cultivars had pH values ranging between pH 3.13 and 3.92. Vanillic acid exerted a concentration, pH, and time-dependent lethal effect toward E. coli O157:H7 in unpasteurized apple juice. Supplementation with 10 mM vanillic acid led to a 5-logarithm reduction in populations after 7 days at both temperatures, but sensory analysis revealed significant differences from and preference for unsupplemented juices. Supplementation with 5 mM vanillic acid accelerated death of E. coli O157:H7, but population reductions ranged from 5 log CFU/ml in low pH juices to none in high pH juices, particularly at 4 degrees C. No sensory difference or preference was detected in two of the six juices at this level of supplementation.

Beverages↗
PubMed2004

Reducing the 137Cs-load in the organism of "Chernobyl" children with apple-pectin.

As a complement of standard radioprotective measures, apple-pectin preparations are given, especially in the Ukraine, to reduce the 137Cs uptake in the organism of children. The question has been raised: is oral pectin also useful when children receive radiologically clean food, or does this polysaccharide only act in binding 137Cs in the gut, blocking its intestinal absorption? In this case, pectin would be useless if radiologically clean food could be given. The study was a randomised, double blind placebo-controlled trial comparing the efficacy of a dry and milled apple-extract containing 15-16% pectin with a similar placebo-powder, in 64 children originating from the same group of contaminated villages of the Gomel oblast. The average 137Cs load was of about 30 Bq/kg bodyweight (BW). The trial was conducted during the simultaneous one-month stay in the sanatorium Silver Spring. In this clean radiological environment only radiologically "clean" food is given to the children. The average reduction of the 137Cs levels in children receiving oral pectin powder was 62.6%, the reduction with "clean" food and placebo was 13.9%, the difference being statistically significant (p <0.01). The reduction of the 137Cs load is medically relevant, as no child in the placebo group reached values below 20 Bq/kg BW (which is considered by Bandazhevsky as potentially associated with specific pathological tissue damages), with an average value of 25.8 +/- 0.8 Bq/kg. The highest value in the apple-pectin group was 15.4 Bq/kg, the average value being 11.3 +/- 0.6 Bq/kg BW.

Administration, Oral↗
PubMed2000

Attraction of apple maggot flies, Rhagoletis pomonella (Diptera: tephritidae) of different physiological states to odour-baited traps in the presence and absence of food.

Adults of apple maggot fly Rhagoletis pomonella (Walsh) of differing physiological states were marked and released in blocks of apple trees ringed by sticky red spheres. Spheres were either unbaited, baited with butyl hexanoate (synthetic host fruit odour) or baited with both butyl hexanoate and ammonium carbonate (synthetic food odour). All trap and lure treatments were compared in the presence or absence of food (bird faeces) in the blocks. Simultaneously, the response of wild immigrant flies to treatments was measured and wild females were dissected to determine state of ovary development. Large proportions (25-40%) of released mature male and female R. pomonella were recovered in blocks having traps baited with butyl hexanoate. Ammonium carbonate did not enhance trap captures and presence of food had little effect on response to synthetic odours by mature R. pomonella. Immature flies of each sex responded weakly to traps and to both types of synthetic lures and may have been arrested in blocks having food. Wild flies of both sexes exhibited a response pattern very similar to mature released flies, regardless of eggload (in the case of wild females). Results indicate that wild R. pomonella immigrating into apple orchards are primarily mature, and not hungry for protein. Behavioural control strategies are discussed in that context.

Animals↗
PubMedDate not supplied

[A protein inhibitor of polygalacturonase in apple fruits treated with aminoethoxyvinylglycine and cobalt chloride].

Ethylene evolution changes were monitored during storage of apple fruits (Malus domestica Borkh., winter variety Mantuanskoe) treated with aminoethoxyvinylglycine and CoCl2. The storage of fruits was shown to be accompanied by changes in the activity of a protein inhibitor of polygalacturonase (PIPG). This inhibitor has been previously isolated from apple fruit tissues. The protein inhibitor of polygalacturonase was also shown to inhibit the activity of an enzyme produced by certain nonpathogenic fungi. The role of PIPG in apple fruit resistance to these fungi is discussed.

Antimutagenic Agents↗
PubMedDate not supplied

Simultaneous determination of six triazolic pesticide residues in apple and pear pulps by liquid chromatography with ultraviolet diode array detection.

A method is described for the simultaneous determination of diclobutrazol, flusilazole, flutriafol, hexaconazole, paclobutrazol, and tetraconazole in apple and pear pulps used in baby food at a limit of 0.01 mg/kg. Apple and pear pulp samples are subjected to selective solid-phase microdispersion (SPMD) with SPE-ED Matrix-38 and acetone-cyclohexane, and the extracts are cleaned up on a Florisil cartridge with hexane-cyclohexane-acetone. The extracts are then analyzed by liquid chromatography with ultraviolet detection, using an octadecylsilane column with a gradient-programmed acetonitrile-water mobile phase. Recoveries were determined by spiking apple and pear pulps with the 6 pesticides under investigation at 0.1, 0.05, 0.03, and 0.01 mg/kg. Six determinations were performed at each level for each pesticide. Recoveries were > or = 70% at the 0.01 mg/kg level.

Calibration↗
PubMedDate not supplied

[Effect of proteinaceous polygalacturonase inhibitors from apple seed tissue on an enzyme isolated from phytopathogenic fungi].

A protein polygalacturonidase inhibitor isolated from fruit of the apple varieties Antonovka and Mantuanskoe differently affects the polygalacturonidases of different phytopathogenic fungi. Three groups of fungi were recognized by the sensitivity of their polygalacturonidases to the inhibitory effect. Storage of apples after harvesting is accompanied by changes in the inhibitor activity, and the time pattern of these changes depends on the variety. An increase in the inhibitor activity occurs concurrently with the elevation in ethylene release characteristic of the stage of elevated respiration (a climacteric increase). The data suggest that a decrease in the apple fruit resistance to microbes at the end of the storage period is related, along with other reasons, to a change in the activity of the protein polygalacturonidase inhibitor.

Enzyme Inhibitors↗
PubMed2001

A bacterial artificial chromosome (BAC) library of Malus floribunda 821 and contig construction for positional cloning of the apple scab resistance gene Vf.

The apple scab resistance gene Vf, originating from the wild species Malus floribunda 821, has been incorporated into a wide variety of apple cultivars through a classical breeding program. With the aim of isolating the Vf gene, a bacterial artificial chromosome (BAC) library consisting of 31 584 clones has been constructed from M. floribunda 821. From the analysis of 88 randomly selected BAC clones, the average insert size is estimated at 125 kb. If it is assumed that the genome size of M. floribunda 821 is 769 Mb/haploid, the library represents about 5x haploid genome equivalents. This provides a 99% probability of finding any specific sequence from this library. PCR-based screening of the library has been carried out using eight random genomic sequence-characterized amplified regions (SCARs), chloroplast- and mitochondria-specific SCARs, and 13 high-density Vf-linked SCAR markers. An average of five positive BAC clones per random SCAR has been obtained, whereas less than 1% of BAC clones are derived from the chloroplast or mitochondrial genomes. Most BAC clones identified with Vf-linked SCAR markers are physically linked. Three BAC contigs along the Vf region have been obtained by assembling physically linked BAC clones based on their fingerprints. The overlapping relatedness of BAC clones has been further confirmed by cytogenetic mapping using fiber fluorescence in situ hybridization (fiber-FISH). The M. floribunda 821 BAC library provides a valuable genetic resource not only for map-based cloning of the Vf gene, but also for finding many other important genes for improving the cultivated apple.

Chromosomes, Artificial, Bacterial↗