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S. P. Vander Kloet - One of the best experts on this subject based on the ideXlab platform.
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Interspecific Variation in Anthocyanins, Phenolics, and Antioxidant Capacity among Genotypes of Highbush and Lowbush Blueberries (Vaccinium Section cyanococcus spp.)
Journal of Agricultural and Food Chemistry, 2001Co-Authors: Wilhelmina Kalt, Ronald L Prior, Daniel A. J. Ryan, Mark K. Ehlenfeldt, S. P. Vander KloetAbstract:Recent interest in the possible protective effects of dietary antioxidant compounds against human degenerative disease has prompted investigation of foods such as Blueberries (Vaccinium sp.), which have a high antioxidant capacity. Fruit obtained from genotypes of highbush Blueberries (Vaccinium corymbosum L.) and lowbush Blueberries (Vaccinium angustifolium Aiton) were analyzed for their antioxidant capacity, their content of anthocyanins, and total phenolic compounds, to evaluate the intraspecific and interspecific variation in these parameters. The method of extraction influenced the composition of fruit extracts; the highest anthocyanin and total phenolic contents and antioxidant capacity were found in extracts obtained using a solvent of acidified aqueous methanol. Regardless of the method, lowbush Blueberries were consistently higher in anthocyanins, total phenolics, and antioxidant capacity, compared with highbush Blueberries. There was no relationship between fruit size and anthocyanin content in ...
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interspecific variation in anthocyanins phenolics and antioxidant capacity among genotypes of highbush and lowbush Blueberries vaccinium section cyanococcus spp
Journal of Agricultural and Food Chemistry, 2001Co-Authors: Wilhelmina Kalt, Ronald L Prior, Daniel A. J. Ryan, Mark K. Ehlenfeldt, Joanna Duy, S. P. Vander KloetAbstract:Recent interest in the possible protective effects of dietary antioxidant compounds against human degenerative disease has prompted investigation of foods such as Blueberries (Vaccinium sp.), which have a high antioxidant capacity. Fruit obtained from genotypes of highbush Blueberries (Vaccinium corymbosum L.) and lowbush Blueberries (Vaccinium angustifolium Aiton) were analyzed for their antioxidant capacity, their content of anthocyanins, and total phenolic compounds, to evaluate the intraspecific and interspecific variation in these parameters. The method of extraction influenced the composition of fruit extracts; the highest anthocyanin and total phenolic contents and antioxidant capacity were found in extracts obtained using a solvent of acidified aqueous methanol. Regardless of the method, lowbush Blueberries were consistently higher in anthocyanins, total phenolics, and antioxidant capacity, compared with highbush Blueberries. There was no relationship between fruit size and anthocyanin content in either species.
Haiqiang Chen - One of the best experts on this subject based on the ideXlab platform.
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Comparison of Water‐Assisted Decontamination Systems of Pulsed Light and Ultraviolet for Salmonella Inactivation on Blueberry, Tomato, and Lettuce
Journal of Food Science, 2019Co-Authors: Runze Huang, Haiqiang ChenAbstract:Fresh produce are vulnerable to pathogens during pre- and postharvest stages. Most fresh vegetable and fruits are consumed directly or merely washed with chlorine. We investigated two emerging decontamination technologies, pulse light (PL) and ultraviolet (UV), in combination with washing (referred as water-assisted PL [WPL] and water-assisted UV [WUV]). Blueberries, grape tomatoes, and iceberg lettuce shreds were tested in this study to represent fresh vegetables and fruits with smooth and rough surfaces. Salmonella spp. were used as a model microorganism due to its prevalence in outbreaks. Spot-inoculation and dip-inoculation were used to simulate potential contaminations during irrigation, harvest, transportation, and processing. Two intensity levels of PL (∼0.15 and 0.3 J/cm2 per pulse; 3 pulses/s) and UV (∼13 and 28 mW/cm2 ) were tested for 1 and 2 min. For all three types of fresh produce, Blueberries, grape tomatoes, and iceberg lettuce shreds, WPL and WUV showed similar Salmonella inactivation effects on fresh produce. For spot-inoculated fresh produce, WPL and WUV treatments reduced 4.5 to 5.7, 4.4 to 5.4, and 1.9 to 3.1 logs of Salmonella on Blueberries, tomatoes, and lettuce shreds, respectively. For dip-inoculated fresh produce, WPL and WUV treatments reduced 1.8 to 2.3, 1.9 to 2.5, and 1.9 to 2.6 logs of Salmonella on Blueberries, tomatoes, and lettuce shreds, respectively. The majority of the WUV and WPL treatments could eliminate Salmonella in the wash water for Blueberries and tomatoes, but not for lettuce. PRACTICAL APPLICATION: Two light systems, pulsed light and UV, for decontamination of fresh produce were evaluated and compared. Results demonstrated that the two systems showed similar decontamination effect on fresh produce, demonstrating that the UV system could be used to replace the pulsed light system to reduce equipment cost.; © 2019 Institute of Food Technologists®.
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atmospheric cold plasma inactivation of aerobic microorganisms on Blueberries and effects on quality attributes
Food Microbiology, 2015Co-Authors: Alison Lacombe, Brendan A Niemira, Joshua B Gurtler, Joseph Sites, Glenn Boyd, Haiqiang ChenAbstract:Abstract Cold plasma (CP) is a novel nonthermal technology, potentially useful in food processing settings. Berries were treated with atmospheric CP for 0, 15, 30, 45, 60, 90, or 120 s at a working distance of 7.5 cm with a mixture of 4 cubic feet/minute (cfm) of CP jet and 7 cfm of ambient air. Blueberries were sampled for total aerobic plate count (APC) and yeast/molds immediately after treatment and at 1, 2, and 7 days. Blueberries were also analyzed for compression firmness, surface color, and total anthocyanins immediately after each treatment. All treatments with CP significantly ( P L * and a * values and 45 s for the b * values. CP can inactivate microorganisms on Blueberries and could be optimized to improve the safety and quality of produce.
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a novel water assisted pulsed light processing for decontamination of Blueberries
Food Microbiology, 2014Co-Authors: Yaoxin Huang, Haiqiang ChenAbstract:Abstract Sample heating and shadowing effect have limited the application of pulsed light (PL) technology for decontamination of fresh produce. In this study, a novel setup using water-assisted PL processing was developed to overcome these limitations. Blueberries inoculated with Escherichia coli O157:H7 or Salmonella were either treated with PL directly (dry PL treatment) or immersed in agitated water during the PL treatment (wet PL treatment) for 5–60 s. Although both pathogens were effectively inactivated by the dry PL treatments, the appearance of the Blueberries was adversely affected and a maximum temperature of 64.8 °C on the blueberry surface was recorded. On the other hand, the visual appearance of Blueberries remained unchanged after wet PL treatments and sample heating was significantly reduced. The wet PL treatments were more effective than chlorine washing on inactivating both pathogens. After a 60-s wet PL treatment, the populations of E. coli O157:H7 inoculated on calyx and skin of Blueberries were reduced by 3.0 and >5.8 log CFU/g, respectively. Salmonella on blueberry calyx and skin was reduced by 3.6 and >5.9 log CFU/g, respectively. No viable bacterial cells were recovered from the water used in the wet PL treatments, demonstrating that this setup could prevent the risk of cross-contamination during fresh produce washing. Our results suggest that this new water-assisted PL treatment could be a potential non-chemical alternative (residue free) to chlorine washing since it is both more effective and environmentally friendly than chlorine washing.
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pressure inactivation of tulane virus a candidate surrogate for human norovirus and its potential application in food industry
International Journal of Food Microbiology, 2013Co-Authors: Xinhui Li, Mu Ye, Hudaa Neetoo, Serguei P Golovan, Haiqiang ChenAbstract:Abstract Human norovirus (HuNoV) is the leading causative agent for foodborne disease. Currently, studies of HuNoV usually rely on surrogates such as murine norovirus (MNV) due to the lack of a suitable cell culture system and a small animal model for HuNoV. Tulane virus (TV), a monkey calicivirus, is a cultivable enteric calicivirus that not only recognizes the same receptors as HuNoV, but is also genetically closely related to HuNoV. In this study, we determined the pH stability of TV and MNV-1, as well as the effect of high hydrostatic pressure (HHP) on inactivating both viruses in aqueous media, Blueberries and oysters. We demonstrated that both TV and MNV-1 were very stable under an acidic environment. They were more resistant to pressure at an acidic environment than at neutral pH. Pressure treatment of 600 MPa for 2 min at different temperatures (4, 21 and 35 °C) barely caused any reduction of TV, as well as MNV-1, on un-wetted (dry) Blueberries. However, both TV and MNV-1 on Blueberries were successfully inactivated by a pressure of ≤ 400 MPa when Blueberries were immersed in phosphate-buffered saline during HHP. Pressure inactivation of both TV and MNV-1 in Blueberries and oysters increased as sample temperature decreased in the order of 4 > 21 > 35 °C. TV was more sensitive to pressure than MNV-1 for the three matrices tested, culture media, Blueberries and oysters. This study provides important information on the use of TV as a surrogate for HuNoV study. Results obtained from this study lay a foundation for designing effective HHP treatments for inactivation of HuNoV in high-risk foods such as berries and oysters.
Gabriel A Leivavalenzuela - One of the best experts on this subject based on the ideXlab platform.
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assessment of internal quality of Blueberries using hyperspectral transmittance and reflectance images with whole spectra or selected wavelengths
Innovative Food Science and Emerging Technologies, 2014Co-Authors: Gabriel A Leivavalenzuela, Jose Miguel AguileraAbstract:Abstract Hyperspectral imaging has been used in previous studies for assessing firmness and soluble solids content of fresh fruit. To assess the applicability of this technique for automatic sorting and grading of Blueberries, we investigated different sensing modes (i.e., reflectance and transmittance), evaluated the effect of fruit orientation on fruit quality prediction, and developed robust prediction models with fewer wavelengths. In this study, a hyperspectral imaging system was used to acquire reflectance and transmittance images from 420 Blueberries in three fruit orientations (i.e., stem end, calyx end and equator) for the spectral region of 400–1000 nm. Mean spectra were extracted from the hyperspectral images of each blueberry. Calibration models for soluble solids content (SSC) and firmness index (FI) were developed using partial least squares regression for the reflectance and transmittance spectra as well as their combination. Further, interval partial least squares (iPLS) regression with 10 different intervals of nine wavelengths was used to reduce the spectral dimensionality. Overall, reflectance gave better results (the best correlation for prediction (R p ) of 0.90 for SSC and 0.78 for FI) than transmittance (R p of 0.76 for SSC and 0.64 for FI). For reflectance, SSC and FI predictions for the stem end orientation were better than for the other two orientations, while fruit orientation had little or insignificant effect on transmittance predictions. Combination of reflectance and transmittance spectra did not yield improved prediction results for both SSC and FI. On average, the prediction errors for iPLS increased by only 5%, compared to PLS for the whole spectra. The research demonstrated that it is feasible to use hyperspectral imaging technique for prediction of internal quality of Blueberries with a few selected wavelengths with results similar to that with whole spectral information. Industrial relevance Because of the distance traveled from the South to the North hemisphere, it is especially important to perform internal and external quality determination for individual fresh Blueberries to ensure their quality upon arrival at the destination. Soluble solids content and firmness are important fruit quality parameters. Hyperspectral imaging has emerged as a new technique for quality and safety inspection of food and agricultural products and could be useful for blueberry quality assessment. However, there are several limitations to be afforded before: technique implementation velocity since this method uses multiple images from contiguous wavelengths (increasing computational costs), fruit light interaction, and fruit orientation effect between others. Specifically, the submitted manuscript presents results in order to demonstrate the hyperspectral imaging technique feasibility with a few selected wavelengths to achieve acceptable results for the prediction of internal quality of Blueberries, thus, this would make it possible to implement the technique in the near future for online commercial sorting and grading of Blueberries.
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automatic detection of orientation and diseases in Blueberries using image analysis to improve their postharvest storage quality
Food Control, 2013Co-Authors: Gabriel A Leivavalenzuela, Jose Miguel AguileraAbstract:Abstract The production of the South American blueberry has increased by over 40% in the last decade. However, during storage and shipping, several problems can lead to rejections. This work proposes a pattern recognition method to automatically distinguish stem and calyx ends and detect damaged berries. First, Blueberries were imaged under standard conditions to extract color and geometrical features. Second, five algorithms were tested to select the best features to be used in the subsequent evaluation of classification algorithms and cross-validation. The Blueberries classes were control, fungally decayed, shriveled, and mechanically damaged. The original 951 features extracted were reduced to 20 or fewer with sequential forward selection. The best classifiers were Support Vector Machine and Linear Discriminant Analysis. Using these classifiers made it possible to successfully distinguish the Blueberries' orientation in 96.8% of the cases. By evaluating damages to fungally decayed, shriveled, and mechanically damaged Blueberries, the average performances of the classifiers were above 97%, 93.3%, and 86% respectively. All of the experiments were evaluated using external images with 95% confidence – 10-fold cross-validation. These results are promising because they will allow for the increase in export quality when implemented in production lines.
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prediction of firmness and soluble solids content of Blueberries using hyperspectral reflectance imaging
Journal of Food Engineering, 2013Co-Authors: Gabriel A Leivavalenzuela, Renfu Lu, Jose Miguel AguileraAbstract:Abstract Currently, Blueberries are inspected and sorted by color, size and/or firmness (or softness) in packing houses, using different inspection techniques like machine vision and mechanical vibration or impact. A new inspection technique is needed for effectively assessing both external features and internal quality attributes of individual Blueberries. This paper reports on the use of hyperspectral imaging technique for predicting the firmness and soluble solids content (SSC) of Blueberries. A pushbroom hyperspectral imaging system was used to acquire hyperspectral reflectance images from 302 Blueberries in two fruit orientations (i.e., stem and calyx ends) for the spectral region of 500–1000 nm. Mean spectra were extracted from the regions of interest for the hyperspectral images of each blueberry. Prediction models were developed based on partial least squares method using cross validation and were externally tested with 25% of the samples. Better firmness predictions ( R = 0.87) were obtained, compared to SSC predictions ( R = 0.79). Fruit orientation had no or insignificant effect on the firmness and SSC predictions. Further analysis showed that Blueberries could be sorted into two classes of firmness. This research has demonstrated the feasibility of implementing hyperspectral imaging technique for sorting Blueberries for firmness and possibly SSC to enhance the product quality and marketability.
Jose Miguel Aguilera - One of the best experts on this subject based on the ideXlab platform.
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assessment of internal quality of Blueberries using hyperspectral transmittance and reflectance images with whole spectra or selected wavelengths
Innovative Food Science and Emerging Technologies, 2014Co-Authors: Gabriel A Leivavalenzuela, Jose Miguel AguileraAbstract:Abstract Hyperspectral imaging has been used in previous studies for assessing firmness and soluble solids content of fresh fruit. To assess the applicability of this technique for automatic sorting and grading of Blueberries, we investigated different sensing modes (i.e., reflectance and transmittance), evaluated the effect of fruit orientation on fruit quality prediction, and developed robust prediction models with fewer wavelengths. In this study, a hyperspectral imaging system was used to acquire reflectance and transmittance images from 420 Blueberries in three fruit orientations (i.e., stem end, calyx end and equator) for the spectral region of 400–1000 nm. Mean spectra were extracted from the hyperspectral images of each blueberry. Calibration models for soluble solids content (SSC) and firmness index (FI) were developed using partial least squares regression for the reflectance and transmittance spectra as well as their combination. Further, interval partial least squares (iPLS) regression with 10 different intervals of nine wavelengths was used to reduce the spectral dimensionality. Overall, reflectance gave better results (the best correlation for prediction (R p ) of 0.90 for SSC and 0.78 for FI) than transmittance (R p of 0.76 for SSC and 0.64 for FI). For reflectance, SSC and FI predictions for the stem end orientation were better than for the other two orientations, while fruit orientation had little or insignificant effect on transmittance predictions. Combination of reflectance and transmittance spectra did not yield improved prediction results for both SSC and FI. On average, the prediction errors for iPLS increased by only 5%, compared to PLS for the whole spectra. The research demonstrated that it is feasible to use hyperspectral imaging technique for prediction of internal quality of Blueberries with a few selected wavelengths with results similar to that with whole spectral information. Industrial relevance Because of the distance traveled from the South to the North hemisphere, it is especially important to perform internal and external quality determination for individual fresh Blueberries to ensure their quality upon arrival at the destination. Soluble solids content and firmness are important fruit quality parameters. Hyperspectral imaging has emerged as a new technique for quality and safety inspection of food and agricultural products and could be useful for blueberry quality assessment. However, there are several limitations to be afforded before: technique implementation velocity since this method uses multiple images from contiguous wavelengths (increasing computational costs), fruit light interaction, and fruit orientation effect between others. Specifically, the submitted manuscript presents results in order to demonstrate the hyperspectral imaging technique feasibility with a few selected wavelengths to achieve acceptable results for the prediction of internal quality of Blueberries, thus, this would make it possible to implement the technique in the near future for online commercial sorting and grading of Blueberries.
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automatic detection of orientation and diseases in Blueberries using image analysis to improve their postharvest storage quality
Food Control, 2013Co-Authors: Gabriel A Leivavalenzuela, Jose Miguel AguileraAbstract:Abstract The production of the South American blueberry has increased by over 40% in the last decade. However, during storage and shipping, several problems can lead to rejections. This work proposes a pattern recognition method to automatically distinguish stem and calyx ends and detect damaged berries. First, Blueberries were imaged under standard conditions to extract color and geometrical features. Second, five algorithms were tested to select the best features to be used in the subsequent evaluation of classification algorithms and cross-validation. The Blueberries classes were control, fungally decayed, shriveled, and mechanically damaged. The original 951 features extracted were reduced to 20 or fewer with sequential forward selection. The best classifiers were Support Vector Machine and Linear Discriminant Analysis. Using these classifiers made it possible to successfully distinguish the Blueberries' orientation in 96.8% of the cases. By evaluating damages to fungally decayed, shriveled, and mechanically damaged Blueberries, the average performances of the classifiers were above 97%, 93.3%, and 86% respectively. All of the experiments were evaluated using external images with 95% confidence – 10-fold cross-validation. These results are promising because they will allow for the increase in export quality when implemented in production lines.
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prediction of firmness and soluble solids content of Blueberries using hyperspectral reflectance imaging
Journal of Food Engineering, 2013Co-Authors: Gabriel A Leivavalenzuela, Renfu Lu, Jose Miguel AguileraAbstract:Abstract Currently, Blueberries are inspected and sorted by color, size and/or firmness (or softness) in packing houses, using different inspection techniques like machine vision and mechanical vibration or impact. A new inspection technique is needed for effectively assessing both external features and internal quality attributes of individual Blueberries. This paper reports on the use of hyperspectral imaging technique for predicting the firmness and soluble solids content (SSC) of Blueberries. A pushbroom hyperspectral imaging system was used to acquire hyperspectral reflectance images from 302 Blueberries in two fruit orientations (i.e., stem and calyx ends) for the spectral region of 500–1000 nm. Mean spectra were extracted from the regions of interest for the hyperspectral images of each blueberry. Prediction models were developed based on partial least squares method using cross validation and were externally tested with 25% of the samples. Better firmness predictions ( R = 0.87) were obtained, compared to SSC predictions ( R = 0.79). Fruit orientation had no or insignificant effect on the firmness and SSC predictions. Further analysis showed that Blueberries could be sorted into two classes of firmness. This research has demonstrated the feasibility of implementing hyperspectral imaging technique for sorting Blueberries for firmness and possibly SSC to enhance the product quality and marketability.
Ronald L Prior - One of the best experts on this subject based on the ideXlab platform.
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flavonoid glycosides and antioxidant capacity of various blackberry blueberry and red grape genotypes determined by high performance liquid chromatography mass spectrometry
Journal of the Science of Food and Agriculture, 2004Co-Authors: Mi Jin Cho, Ronald L Prior, Luke R Howard, John R ClarkAbstract:Anthocyanin and flavonol glycosides of various blackberry, blueberry and red wine grape genotypes were identified and measured by a high-performance liquid chromatographic (HPLC) separation method with photodiode array (PDA) and mass spectrometric (MS) detection. With this method, two distinct elution regions of anthocyanins and flavonols were obtained with near baseline separation of most compounds. Blackberry, blueberry and red wine grape genotypes varied markedly in total anthocyanins and total flavonols as well as oxygen radical absorbance capacity (ORAC). The respective ranges of total anthocyanin (TA) and total flavonol (TF) contents of tested samples were: blackberries, 1143.9-2415.4 and 102.0-160.2mgkg −1 ; Blueberries, 1435.2-8227.3 and 172.5-327.5mgkg −1 ; and red wine grapes, 380.9-7904.7 and 21.0-322.2mgkg −1 . Antioxidant activities and contents of total anthocyanins and total flavonols in blackberries, Blueberries and red wine grapes were highly correlated, with linear relationships between ORAC and TA (rxy = 0.94) and TF (rxy = 0.90) for grapes, TA (rxy = 0.95) for Blueberries and TA (rxy = 0.74) for blackberries. 2004 Society of Chemical Industry
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interspecific variation in anthocyanins phenolics and antioxidant capacity among genotypes of highbush and lowbush Blueberries vaccinium section cyanococcus spp
Journal of Agricultural and Food Chemistry, 2001Co-Authors: Wilhelmina Kalt, Ronald L Prior, Daniel A. J. Ryan, Mark K. Ehlenfeldt, Joanna Duy, S. P. Vander KloetAbstract:Recent interest in the possible protective effects of dietary antioxidant compounds against human degenerative disease has prompted investigation of foods such as Blueberries (Vaccinium sp.), which have a high antioxidant capacity. Fruit obtained from genotypes of highbush Blueberries (Vaccinium corymbosum L.) and lowbush Blueberries (Vaccinium angustifolium Aiton) were analyzed for their antioxidant capacity, their content of anthocyanins, and total phenolic compounds, to evaluate the intraspecific and interspecific variation in these parameters. The method of extraction influenced the composition of fruit extracts; the highest anthocyanin and total phenolic contents and antioxidant capacity were found in extracts obtained using a solvent of acidified aqueous methanol. Regardless of the method, lowbush Blueberries were consistently higher in anthocyanins, total phenolics, and antioxidant capacity, compared with highbush Blueberries. There was no relationship between fruit size and anthocyanin content in either species.
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Interspecific Variation in Anthocyanins, Phenolics, and Antioxidant Capacity among Genotypes of Highbush and Lowbush Blueberries (Vaccinium Section cyanococcus spp.)
Journal of Agricultural and Food Chemistry, 2001Co-Authors: Wilhelmina Kalt, Ronald L Prior, Daniel A. J. Ryan, Mark K. Ehlenfeldt, S. P. Vander KloetAbstract:Recent interest in the possible protective effects of dietary antioxidant compounds against human degenerative disease has prompted investigation of foods such as Blueberries (Vaccinium sp.), which have a high antioxidant capacity. Fruit obtained from genotypes of highbush Blueberries (Vaccinium corymbosum L.) and lowbush Blueberries (Vaccinium angustifolium Aiton) were analyzed for their antioxidant capacity, their content of anthocyanins, and total phenolic compounds, to evaluate the intraspecific and interspecific variation in these parameters. The method of extraction influenced the composition of fruit extracts; the highest anthocyanin and total phenolic contents and antioxidant capacity were found in extracts obtained using a solvent of acidified aqueous methanol. Regardless of the method, lowbush Blueberries were consistently higher in anthocyanins, total phenolics, and antioxidant capacity, compared with highbush Blueberries. There was no relationship between fruit size and anthocyanin content in ...
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identification of procyanidins and anthocyanins in Blueberries and cranberries vaccinium spp using high performance liquid chromatography mass spectrometry
Journal of Agricultural and Food Chemistry, 2001Co-Authors: Ronald L Prior, Sheryl A Lazarus, Guohua Cao, Helen U Muccitelli, John F HammerstoneAbstract:Blueberries and cranberries were analyzed for procyanidins using normal-phase HPLC/MS. Monomers, identified as (+)-catechin and (−)-epicatechin, and a series of oligomers were detected in Blueberries, and MS data confirmed that the oligomers consisted of (epi)catechin units that were exclusively singly linked (B-type). The procyanidin “fingerprints” were similar for Tifblue and Rubel but higher than that for lowbush Blueberries. In whole cranberries, (−)-epicatechin was present, along with a complex series of oligomers. Both A-type (contained only one double linkage per oligomer) and B-type oligomers were present. Two commercial cranberry juices exhibited similar procyanidin profiles, except that one contained increased quantitites. There were processing effects on the procyanidin content of cranberry extract and juices when compared to those of the unprocessed fruits. Monomer, dimers, and A-type trimers were the primary procyanidins, with only trace levels of the B-type trimers and A-type tetramers and w...