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Markus Fischer - One of the best experts on this subject based on the ideXlab platform.

  • Development of a Multiplex Real-Time PCR for Determination of Apricot in Marzipan Using the Plexor System
    2017
    Co-Authors: Stefanie Schelm, Ilka Haase, Christin Fischer, Markus Fischer
    Abstract:

    Marzipan is a confectionary which is mostly offered in form of filled chocolate, pralines, or pure. According to the German guidelines for oil seeds only almonds, sugar and water are admitted ingredients of Marzipan. A product very similar in taste is persipan which is used in the confectionary industry because of its stronger flavor. For persipan production almonds are replaced by debittered apricot or peach kernels. To guarantee high quality products for consumers, German raw paste producers have agreed a limit of apricot kernels in Marzipan raw paste of 0.5%. Different DNA-based methods for quantitation of persipan contaminations in Marzipan are already published. To increase the detection specificity compared to published intercalation dye based assays, the present work demonstrate the utilization of a multiplex real-time PCR based on the Plexor technology. Thus, the present work enables the detection of at least 0.1% apricot DNA in almond DNA or less. By analyzing DNA mixtures, the theoretical limit of quantification of the duplex PCR for the quantitation of persipan raw paste DNA in Marzipan raw paste DNA was determined as 0.05%.

  • Development of a Multiplex Real-Time PCR for Determination of Apricot in Marzipan Using the Plexor System
    2016
    Co-Authors: Stefanie Schelm, Ilka Haase, Christin Fischer, Markus Fischer
    Abstract:

    Marzipan is a confectionary which is mostly offered in form of filled chocolate, pralines, or pure. According to the German guidelines for oil seeds only almonds, sugar and water are admitted ingredients of Marzipan. A product very similar in taste is persipan which is used in the confectionary industry because of its stronger flavor. For persipan production almonds are replaced by debittered apricot or peach kernels. To guarantee high quality products for consumers, German raw paste producers have agreed a limit of apricot kernels in Marzipan raw paste of 0.5%. Different DNA-based methods for quantitation of persipan contaminations in Marzipan are already published. To increase the detection specificity compared to published intercalation dye-based assays, the present work demonstrate the utilization of a multiplex real-time PCR based on the Plexor technology. Thus, the present work enables the detection of at least 0.1% apricot DNA in almond DNA or less. By analyzing DNA mixtures, the theoretical limit of quantification of the duplex PCR for the quantitation of persipan raw paste DNA in Marzipan raw paste DNA was determined as 0.05%

  • Real-Time PCR Assays for the Quantitation of rDNA from Apricot and Other Plant Species in Marzipan
    2016
    Co-Authors: Ilka Haase, Reinhard Matissek, Philipp Brüning, Markus Fischer
    Abstract:

    Marzipan or Marzipan raw paste is a typical German sweet which is consumed directly or is used as an ingredient in the bakery industry/confectionery (e.g., in stollen) and as filling for chocolate candies. Almonds (blanched and pealed) and sugar are the only ingredients for Marzipan production according to German food guidelines. Especially for the confectionery industry, the use of persipan, which contains apricot or peach kernels instead of almonds, is preferred due to its stronger aroma. In most of the companies, both raw pastes are produced, in most cases on the same production line, running the risk of an unintended cross contamination. Additionally, due to high almond market values, dilutions of Marzipan with cheaper seeds may occur. Especially in the case of apricot and almond, the close relationship of both species is a challenge for the analysis. DNA based methods for the qualitative detection of apricot, peach, pea, bean, lupine, soy, cashew, pistachio, and chickpea in Marzipan have recently been published. In this study, different quantitation strategies on the basis of real-time PCR have been evaluated and a relative quantitation method with a reference amplification product was shown to give the best results. As the real-time PCR is based on the high copy rDNA-cluster, even contaminations

  • Marzipan: Polymerase Chain Reaction-Driven Methods for Authenticity Control
    2016
    Co-Authors: Philipp Brüning, Ilka Haase, Reinhard Matissek, Markus Fischer
    Abstract:

    According to German food guidelines, almonds are the only oilseed ingredient allowed for the production of Marzipan. Persipan is a Marzipan surrogate in which the almonds are replaced by apricot or peach kernels. Cross-contamination of Marzipan products with persipan may occur if both products are produced using the same production line. Adulterations or dilutions, respectively, of Marzipan with other plant-derived products, for example, lupine or pea, have also been found. Almond and apricot plants are closely related. Consequently, classical analytical methods for the identification/differentiation often fail or are not sensitive enough to quantify apricot concentrations below 1%. Polymerase chain reaction (PCR)-based methods have been shown to enable the differentiation of closely related plant species in the past. These methods are characterized by high specificity and low detection limits. Isolation methods were developed and evaluated especially with respect to the matrix Marzipan in terms of yield, purity, integrity, and amplificability of the isolated DNA. For the reliable detection of apricot, peach, pea, bean, lupine, soy, cashew, pistachio, and chickpea, qualitative standard and duplex PCR methods were developed and established. The applicability of these methods was tested by cross-reaction studies and analysis of spiked raw pastes. Contaminations at the level of 0.1% could be detected

  • real time pcr assays for the quantitation of rdna from apricot and other plant species in Marzipan
    2013
    Co-Authors: Ilka Haase, Philipp Bruning, Reinhard Matissek, Markus Fischer
    Abstract:

    Marzipan or Marzipan raw paste is a typical German sweet which is consumed directly or is used as an ingredient in the bakery industry/confectionery (e.g., in stollen) and as filling for chocolate candies. Almonds (blanched and pealed) and sugar are the only ingredients for Marzipan production according to German food guidelines. Especially for the confectionery industry, the use of persipan, which contains apricot or peach kernels instead of almonds, is preferred due to its stronger aroma. In most of the companies, both raw pastes are produced, in most cases on the same production line, running the risk of an unintended cross contamination. Additionally, due to high almond market values, dilutions of Marzipan with cheaper seeds may occur. Especially in the case of apricot and almond, the close relationship of both species is a challenge for the analysis. DNA based methods for the qualitative detection of apricot, peach, pea, bean, lupine, soy, cashew, pistachio, and chickpea in Marzipan have recently bee...

Ilka Haase - One of the best experts on this subject based on the ideXlab platform.

  • Development of a Multiplex Real-Time PCR for Determination of Apricot in Marzipan Using the Plexor System
    2017
    Co-Authors: Stefanie Schelm, Ilka Haase, Christin Fischer, Markus Fischer
    Abstract:

    Marzipan is a confectionary which is mostly offered in form of filled chocolate, pralines, or pure. According to the German guidelines for oil seeds only almonds, sugar and water are admitted ingredients of Marzipan. A product very similar in taste is persipan which is used in the confectionary industry because of its stronger flavor. For persipan production almonds are replaced by debittered apricot or peach kernels. To guarantee high quality products for consumers, German raw paste producers have agreed a limit of apricot kernels in Marzipan raw paste of 0.5%. Different DNA-based methods for quantitation of persipan contaminations in Marzipan are already published. To increase the detection specificity compared to published intercalation dye based assays, the present work demonstrate the utilization of a multiplex real-time PCR based on the Plexor technology. Thus, the present work enables the detection of at least 0.1% apricot DNA in almond DNA or less. By analyzing DNA mixtures, the theoretical limit of quantification of the duplex PCR for the quantitation of persipan raw paste DNA in Marzipan raw paste DNA was determined as 0.05%.

  • Development of a Multiplex Real-Time PCR for Determination of Apricot in Marzipan Using the Plexor System
    2016
    Co-Authors: Stefanie Schelm, Ilka Haase, Christin Fischer, Markus Fischer
    Abstract:

    Marzipan is a confectionary which is mostly offered in form of filled chocolate, pralines, or pure. According to the German guidelines for oil seeds only almonds, sugar and water are admitted ingredients of Marzipan. A product very similar in taste is persipan which is used in the confectionary industry because of its stronger flavor. For persipan production almonds are replaced by debittered apricot or peach kernels. To guarantee high quality products for consumers, German raw paste producers have agreed a limit of apricot kernels in Marzipan raw paste of 0.5%. Different DNA-based methods for quantitation of persipan contaminations in Marzipan are already published. To increase the detection specificity compared to published intercalation dye-based assays, the present work demonstrate the utilization of a multiplex real-time PCR based on the Plexor technology. Thus, the present work enables the detection of at least 0.1% apricot DNA in almond DNA or less. By analyzing DNA mixtures, the theoretical limit of quantification of the duplex PCR for the quantitation of persipan raw paste DNA in Marzipan raw paste DNA was determined as 0.05%

  • Real-Time PCR Assays for the Quantitation of rDNA from Apricot and Other Plant Species in Marzipan
    2016
    Co-Authors: Ilka Haase, Reinhard Matissek, Philipp Brüning, Markus Fischer
    Abstract:

    Marzipan or Marzipan raw paste is a typical German sweet which is consumed directly or is used as an ingredient in the bakery industry/confectionery (e.g., in stollen) and as filling for chocolate candies. Almonds (blanched and pealed) and sugar are the only ingredients for Marzipan production according to German food guidelines. Especially for the confectionery industry, the use of persipan, which contains apricot or peach kernels instead of almonds, is preferred due to its stronger aroma. In most of the companies, both raw pastes are produced, in most cases on the same production line, running the risk of an unintended cross contamination. Additionally, due to high almond market values, dilutions of Marzipan with cheaper seeds may occur. Especially in the case of apricot and almond, the close relationship of both species is a challenge for the analysis. DNA based methods for the qualitative detection of apricot, peach, pea, bean, lupine, soy, cashew, pistachio, and chickpea in Marzipan have recently been published. In this study, different quantitation strategies on the basis of real-time PCR have been evaluated and a relative quantitation method with a reference amplification product was shown to give the best results. As the real-time PCR is based on the high copy rDNA-cluster, even contaminations

  • Marzipan: Polymerase Chain Reaction-Driven Methods for Authenticity Control
    2016
    Co-Authors: Philipp Brüning, Ilka Haase, Reinhard Matissek, Markus Fischer
    Abstract:

    According to German food guidelines, almonds are the only oilseed ingredient allowed for the production of Marzipan. Persipan is a Marzipan surrogate in which the almonds are replaced by apricot or peach kernels. Cross-contamination of Marzipan products with persipan may occur if both products are produced using the same production line. Adulterations or dilutions, respectively, of Marzipan with other plant-derived products, for example, lupine or pea, have also been found. Almond and apricot plants are closely related. Consequently, classical analytical methods for the identification/differentiation often fail or are not sensitive enough to quantify apricot concentrations below 1%. Polymerase chain reaction (PCR)-based methods have been shown to enable the differentiation of closely related plant species in the past. These methods are characterized by high specificity and low detection limits. Isolation methods were developed and evaluated especially with respect to the matrix Marzipan in terms of yield, purity, integrity, and amplificability of the isolated DNA. For the reliable detection of apricot, peach, pea, bean, lupine, soy, cashew, pistachio, and chickpea, qualitative standard and duplex PCR methods were developed and established. The applicability of these methods was tested by cross-reaction studies and analysis of spiked raw pastes. Contaminations at the level of 0.1% could be detected

  • real time pcr assays for the quantitation of rdna from apricot and other plant species in Marzipan
    2013
    Co-Authors: Ilka Haase, Philipp Bruning, Reinhard Matissek, Markus Fischer
    Abstract:

    Marzipan or Marzipan raw paste is a typical German sweet which is consumed directly or is used as an ingredient in the bakery industry/confectionery (e.g., in stollen) and as filling for chocolate candies. Almonds (blanched and pealed) and sugar are the only ingredients for Marzipan production according to German food guidelines. Especially for the confectionery industry, the use of persipan, which contains apricot or peach kernels instead of almonds, is preferred due to its stronger aroma. In most of the companies, both raw pastes are produced, in most cases on the same production line, running the risk of an unintended cross contamination. Additionally, due to high almond market values, dilutions of Marzipan with cheaper seeds may occur. Especially in the case of apricot and almond, the close relationship of both species is a challenge for the analysis. DNA based methods for the qualitative detection of apricot, peach, pea, bean, lupine, soy, cashew, pistachio, and chickpea in Marzipan have recently bee...

Tetiana Nezveshchukkohut - One of the best experts on this subject based on the ideXlab platform.

  • determining the rational concentration of dry demineralized whey in a formulationfor Marzipan pastes
    2020
    Co-Authors: Mihailo Kravchenko, Larysa Rybchuk, Dina Fedorova, Roman Romanenko, Vladimir Piddubnyi, Inna Danyliuk, Karina Palamarek, Tatiana Marusyak, Tetiana Nezveshchukkohut
    Abstract:

    Results obtained in the studies of rheological, surface and sensory characteristics of Marzipan paste containing dry demineralized whey (DDW) are presented in this paper. Positive effect of DDW on sensory characteristics of model compositions of Marzipan pastes was established. Component compatibility of DDW and almond nut has been confirmed. It has been established experimentally that DDW brings about changes in structural state of Marzipan pastes by changing quantitative values of rheological and surface characteristics. It was established that an increase in DDW concentration entails growth of strain and plasticity indices and a decrease in elasticity and resilience indices of Marzipan pastes which generally improves formability. As it was confirmed by the results from comprehensive studies, there is a possibility of partial replacement of import-dependent raw materials in composition of Marzipan paste and, respectively, cut of cost of final product. Technological feasibility of using glycerin in compositions of DDW-containing Marzipan pastes to improve their plasticity and compliance while maintaining high formability was substantiated. The rational content of glycerin in compositions of Marzipan pastes was established which makes it possible to adjust surface properties within specified limits for pasty dressing semi-finished products from Marzipan pastes. Lines of differentiated use of Marzipan pastes with various weight fractions of DDW in confectionery production as dressing semi-finished products were offered: TICP Marzipan paste with DDW mass fraction of 20 % for topping and spreading interlayers in wads and confectionery products. Corresponding figure of 30 % was recommended for making sweets and molding figured confectionary products

  • determining the rational concentration of dry demineralized whey in a formulation for Marzipan pastes
    2020
    Co-Authors: Mihailo Kravchenko, Larysa Rybchuk, Dina Fedorova, Roman Romanenko, Vladimir Piddubnyi, Inna Danyliuk, Karina Palamarek, Tatiana Marusyak, Tetiana Nezveshchukkohut
    Abstract:

    Results obtained in the studies of rheological, surface and sensory characteristics of Marzipan paste containing dry demineralized whey (DDW) are presented in this paper. Positive effect of DDW on sensory characteristics of model compositions of Marzipan pastes was established. Component compatibility of DDW and almond nut has been confirmed. It has been established experimentally that DDW brings about changes in structural state of Marzipan pastes by changing quantitative values of rheological and surface characteristics. It was established that an increase in DDW concentration entails growth of strain and plasticity indices and a decrease in elasticity and resilience indices of Marzipan pastes which generally improves formability. As it was confirmed by the results from comprehensive studies, there is a possibility of partial replacement of import-dependent raw materials in composition of Marzipan paste and, respectively, cut of cost of final product. Technological feasibility of using glycerin in compositions of DDW-containing Marzipan pastes to improve their plasticity and compliance while maintaining high formability was substantiated. The rational content of glycerin in compositions of Marzipan pastes was established which makes it possible to adjust surface properties within specified limits for pasty dressing semi-finished products from Marzipan pastes. Lines of differentiated use of Marzipan pastes with various weight fractions of DDW in confectionery production as dressing semi-finished products were offered: TICP Marzipan paste with DDW mass fraction of 20 % for topping and spreading interlayers in wads and confectionery products. Corresponding figure of 30 % was recommended for making sweets and molding figured confectionary products.

Karlheinz Engel - One of the best experts on this subject based on the ideXlab platform.

  • apricot dna as an indicator for persipan detection and quantitation in Marzipan using ligation dependent probe amplification
    2012
    Co-Authors: Florian Luber, Anja Demmel, Anne Hosken, Ulrich Busch, Karlheinz Engel
    Abstract:

    The confectionery ingredient Marzipan is exclusively prepared from almond kernels and sugar. The potential use of apricot kernels, so-called persipan, is an important issue for the quality assessment of Marzipan. Therefore, a ligation-dependent probe amplification (LPA) assay was developed that enables a specific and sensitive detection of apricot DNA, as an indicator for the presence of persipan. The limit of detection was determined to be 0.1% persipan in Marzipan. The suitability of the method was confirmed by the analysis of 20 commercially available food samples. The integration of a Prunus -specific probe in the LPA assay as a reference allowed for the relative quantitation of persipan in Marzipan. The limit of quantitation was determined to be 0.5% persipan in Marzipan. The analysis of two self-prepared mixtures of Marzipan and persipan demonstrated the applicability of the quantitation method at concentration levels of practical relevance for quality control.

  • Apricot DNA as an Indicator for Persipan: Detection and Quantitation in Marzipan Using Ligation-Dependent Probe Amplification
    2012
    Co-Authors: Florian Luber, Anja Demmel, Anne Hosken, Ulrich Busch, Karlheinz Engel
    Abstract:

    The confectionery ingredient Marzipan is exclusively prepared from almond kernels and sugar. The potential use of apricot kernels, so-called persipan, is an important issue for the quality assessment of Marzipan. Therefore, a ligation-dependent probe amplification (LPA) assay was developed that enables a specific and sensitive detection of apricot DNA, as an indicator for the presence of persipan. The limit of detection was determined to be 0.1% persipan in Marzipan. The suitability of the method was confirmed by the analysis of 20 commercially available food samples. The integration of a Prunus-specific probe in the LPA assay as a reference allowed for the relative quantitation of persipan in Marzipan. The limit of quantitation was determined to be 0.5% persipan in Marzipan. The analysis of two self-prepared mixtures of Marzipan and persipan demonstrated the applicability of the quantitation method at concentration levels of practical relevance for quality control

Reinhard Matissek - One of the best experts on this subject based on the ideXlab platform.

  • Real-Time PCR Assays for the Quantitation of rDNA from Apricot and Other Plant Species in Marzipan
    2016
    Co-Authors: Ilka Haase, Reinhard Matissek, Philipp Brüning, Markus Fischer
    Abstract:

    Marzipan or Marzipan raw paste is a typical German sweet which is consumed directly or is used as an ingredient in the bakery industry/confectionery (e.g., in stollen) and as filling for chocolate candies. Almonds (blanched and pealed) and sugar are the only ingredients for Marzipan production according to German food guidelines. Especially for the confectionery industry, the use of persipan, which contains apricot or peach kernels instead of almonds, is preferred due to its stronger aroma. In most of the companies, both raw pastes are produced, in most cases on the same production line, running the risk of an unintended cross contamination. Additionally, due to high almond market values, dilutions of Marzipan with cheaper seeds may occur. Especially in the case of apricot and almond, the close relationship of both species is a challenge for the analysis. DNA based methods for the qualitative detection of apricot, peach, pea, bean, lupine, soy, cashew, pistachio, and chickpea in Marzipan have recently been published. In this study, different quantitation strategies on the basis of real-time PCR have been evaluated and a relative quantitation method with a reference amplification product was shown to give the best results. As the real-time PCR is based on the high copy rDNA-cluster, even contaminations

  • Marzipan: Polymerase Chain Reaction-Driven Methods for Authenticity Control
    2016
    Co-Authors: Philipp Brüning, Ilka Haase, Reinhard Matissek, Markus Fischer
    Abstract:

    According to German food guidelines, almonds are the only oilseed ingredient allowed for the production of Marzipan. Persipan is a Marzipan surrogate in which the almonds are replaced by apricot or peach kernels. Cross-contamination of Marzipan products with persipan may occur if both products are produced using the same production line. Adulterations or dilutions, respectively, of Marzipan with other plant-derived products, for example, lupine or pea, have also been found. Almond and apricot plants are closely related. Consequently, classical analytical methods for the identification/differentiation often fail or are not sensitive enough to quantify apricot concentrations below 1%. Polymerase chain reaction (PCR)-based methods have been shown to enable the differentiation of closely related plant species in the past. These methods are characterized by high specificity and low detection limits. Isolation methods were developed and evaluated especially with respect to the matrix Marzipan in terms of yield, purity, integrity, and amplificability of the isolated DNA. For the reliable detection of apricot, peach, pea, bean, lupine, soy, cashew, pistachio, and chickpea, qualitative standard and duplex PCR methods were developed and established. The applicability of these methods was tested by cross-reaction studies and analysis of spiked raw pastes. Contaminations at the level of 0.1% could be detected

  • real time pcr assays for the quantitation of rdna from apricot and other plant species in Marzipan
    2013
    Co-Authors: Ilka Haase, Philipp Bruning, Reinhard Matissek, Markus Fischer
    Abstract:

    Marzipan or Marzipan raw paste is a typical German sweet which is consumed directly or is used as an ingredient in the bakery industry/confectionery (e.g., in stollen) and as filling for chocolate candies. Almonds (blanched and pealed) and sugar are the only ingredients for Marzipan production according to German food guidelines. Especially for the confectionery industry, the use of persipan, which contains apricot or peach kernels instead of almonds, is preferred due to its stronger aroma. In most of the companies, both raw pastes are produced, in most cases on the same production line, running the risk of an unintended cross contamination. Additionally, due to high almond market values, dilutions of Marzipan with cheaper seeds may occur. Especially in the case of apricot and almond, the close relationship of both species is a challenge for the analysis. DNA based methods for the qualitative detection of apricot, peach, pea, bean, lupine, soy, cashew, pistachio, and chickpea in Marzipan have recently bee...

  • Marzipan polymerase chain reaction driven methods for authenticity control
    2011
    Co-Authors: Philipp Bruning, Ilka Haase, Reinhard Matissek, Markus Fischer
    Abstract:

    According to German food guidelines, almonds are the only oilseed ingredient allowed for the production of Marzipan. Persipan is a Marzipan surrogate in which the almonds are replaced by apricot or peach kernels. Cross-contamination of Marzipan products with persipan may occur if both products are produced using the same production line. Adulterations or dilutions, respectively, of Marzipan with other plant-derived products, for example, lupine or pea, have also been found. Almond and apricot plants are closely related. Consequently, classical analytical methods for the identification/differentiation often fail or are not sensitive enough to quantify apricot concentrations below 1%. Polymerase chain reaction (PCR)-based methods have been shown to enable the differentiation of closely related plant species in the past. These methods are characterized by high specificity and low detection limits. Isolation methods were developed and evaluated especially with respect to the matrix Marzipan in terms of yield,...