Not-from-concentrate pilot plant 'Wonderful' cultivar pomegranate juice changes: Quality.

Colorful fruits conveying astringent beverages providing well documented health-benefits may present clarification, turbidity and sedimentation problems. Hydraulic pressing whole 'Wonderful' pomegranates and ultrafiltration followed by high temperature short-time pasteurization was used to mimic the dominant U.S. commercial juicing protocol, delivering not-from-concentrate juices, stored at 4 and 25 °C for 3 months. A goal was to avoid expensive and complicated clarification and fining steps. Data were subjected to an analysis of variance and principal components analysis. Changes in quality attributes, organic acids and anthocyanidins are presented. Hydraulic pressing, ultrafiltration and initial pasteurization had minor effects on color parameters, organic acids and anthocyanidins. There were no significant temperature, time or factorial effects for all color parameters during storage of the not-from-concentrate pasteurized juices. However, there were significant time- and temperature-effect decreases in organic acids and anthocyanidins. This is the first report on quality attributes in ultrafiltered, pasteurized and stored not-from-concentrate 'Wonderful' pomegranate juice.

Physicochemical properties and aroma volatile profiles in a diverse collection of California-grown pomegranate (Punica granatum L.) germplasm.

Colorful antioxidant-rich fruits often convey astringency and sourness that juice consumers may not appreciate. We assessed properties in juices from a collection of California-grown pomegranate from the National Clonal Germplasm Repository. The goal was to evaluate overall differences in germplasm with quality traits classified as sweet, sweet-sour and sour. Previous relationships noted in sweet and sour cultivar attributes were observed. Wonderful generally clustered with sweet-sour and sour cultivars. Sweet low acid cultivars occasionally clustered closely with Wonderful which is hard to rationalize. The dominant compounds were 3-hexenol and 1-hexanol which allowed separation of Kara Gul, Haku-botan and Wonderful. Aldehyde and terpene content can be used to characterize cultivars. The study represents the first data on variation in juice qualities in different sweet, sweet-sour and sour cultivars, grown in California, compared with Wonderful. Data may help the juice industry better select raw juice materials in order to ultimately satisfy consumers.

Non echo planar, diffusion-weighted magnetic resonance imaging (periodically rotated overlapping parallel lines with enhanced reconstruction sequence) compared with echo planar imaging for the detection of middle-ear cholesteatoma.

OBJECTIVES: We evaluated use of the periodically rotated overlapping parallel lines with enhanced reconstruction diffusion-weighted imaging sequence, compared with conventional echo planar magnetic resonance imaging, in the detection of middle-ear cholesteatoma. MATERIAL AND METHODS: Sixteen patients awaiting second-stage combined approach tympanoplasty and three patients awaiting first-stage combined approach tympanoplasty underwent magnetic resonance imaging with both (1) the periodically rotated overlapping parallel lines with enhanced reconstruction sequence (i.e. non echo planar imaging) and (2) the array spatial sensitivity encoding technique sequence (i.e. echo planar imaging). Two neuroradiologists independently evaluated the images produced by both sequences. Radiology findings were correlated with surgical findings. RESULTS AND ANALYSIS: Seven cholesteatomas were found at surgery. Neither of the assessed imaging sequences were able to detect cholesteatoma of less than 4 mm. Rates for sensitivity, specificity, and positive and negative predictive values are presented. CONCLUSION: Decisions on whether or not to operate for cholesteatoma cannot be made based on the two imaging sequences assessed, as evaluated in this study. Other contributing factors are discussed, such as the radiological learning curve and technical limitations of the magnetic resonance imaging equipment.

Heart rate and blood pressure effects during caloric vestibular testing.

OBJECTIVES: To determine whether the caloric vestibular test causes significant changes in heart rate and mean arterial blood pressure. MATERIALS AND METHODS: Changes in heart rate and mean arterial blood pressure before and after caloric irrigation were compared with the degree of nystagmus (as measured by maximum slow phase velocity) and the patient's subjective dizziness (scored from 0 to 10). A cardiologist reviewed each patient's heart rate and mean arterial blood pressure changes. Patients' anxiety levels were also assessed. RESULTS: Eighteen patients were recruited. There were no adverse events in any patient. There were no overall significant differences between the heart rate and mean arterial pressure before and after each irrigation. There was a significant correlation between the maximum slow phase velocity and patients' subjective dizziness scores. CONCLUSION: Heart rate and mean arterial blood pressure are not significantly influenced by the caloric vestibular test. This preliminary study will enable patients with stable cardiovascular disease to be recruited for further risk determination.

Using microwave distillation-solid-phase microextraction--gas chromatography--mass spectrometry for analyzing fish tissue.

A technique for the analysis of the volatile compounds from fish tissue employing microwave distillation-solid-phase microextraction-gas chromatography-mass spectrometry is described. A qualitative listing of 174 compounds observed in the headspace is given, and a quantitative method for the determination of the off-flavor contaminants (2-methylisoborneol and geosmin) is presented. Borneol and decahydro-1-naphthol are used as the surrogate and internal standards, respectively. A linear calibration curve is obtained for 0.1 to 5 ppb with a recovery level of 60% at 2.5 ppb. Comparison of the instrumental method with a human flavor checker showed good agreement.

Analysis of 2-methylisoborneol and geosmin in catfish by microwave distillation--solid-phase microextraction.

The semivolatile cyclic alcohols 2-methylisoborneol (MIB) and geosmin (GSM) impart muddy or musty flavors to water and food products. A rapid quantitative analytical technique has been developed whereby microwave distillation is used to remove the volatile organic compounds from a lipophilic matrix into an aqueous matrix. Solid-phase microextraction (MD-SPME) is then used to extract and concentrate the analytes, which are then desorbed in the injection port of a gas chromatograph/mass spectrometer (GC/MS) for analysis. Limits of detection are 0.01 microg/kg and limits of quantification are 0.1 microg/kg. MD-SPME is comparable in precision, requires no solvents, and is faster than current methods of analysis. This methodology allows detection of MIB and GSM at concentrations below human sensory thresholds in fish tissue.