@misc{13271,
  abstract     = {{Pasteurization is the prevalent method for stabilizing cloudy apple juice and prolonging its shelf life, but can also impair quality. Therefore, it is necessary to investigate and quantify the chemical, physical and sensory effects of this treatment. In this study, cloudy apple juice was treated at different time-temperature combinations with equivalent microbial lethality with 161.6 PU. These can be categorized as low temperature/long time (LTLT with 70°C and 80°C) or high temperature/short time (HTST with 90°C, 100°C and 105°C) treatments. The results were compared to those of untreated juice. HTST treatment had significantly less impact on the juice compared to LTLT treatment. LTLT-treated juices were characterized by different sensory attributes, such as raisin and caramel odor and bitter taste. In contrast, the untreated and HTST-treated juices exhibited odors like pear and lemon. There were also significant differences in turbidity, sugar composition, viscosity and a heightened 5-(hydroxymethyl)furfural (HMF) content with LTLT treatment. In summary, HTST-treated juices are more similar to the untreated juices and are rated higher in terms of quality characteristics. The lowest pasteurization temperature of 70°C results in the greatest deterioration of juice quality. It can be concluded that different pasteurization conditions showed different effects on juice quality, despite having the same microbiological lethality of 161.6 PU. Results can be considered when designing pasteurization processes.}},
  author       = {{Katsch, Linda and Sokolowsky, Martina and Gibson, Brian and Schneider, Jan}},
  booktitle    = {{Applied Food Research}},
  issn         = {{2772-5022}},
  keywords     = {{Cloudy apple juice, HTST, juice pasteurization, sensory analysis, process optimization, equivalent microbial lethality}},
  number       = {{2}},
  publisher    = {{Elsevier}},
  title        = {{{Influence of different pasteurization conditions with equivalent pasteurization units on chemical, physical, and sensory properties of cloudy apple juice}}},
  doi          = {{10.1016/j.afres.2025.101471}},
  volume       = {{5}},
  year         = {{2025}},
}

@misc{11607,
  abstract     = {{Pasteurization of bottles and cans is an important technique for biological stabilization of beer as well as mixed beer drinks, malt beer and non-alcoholic beers. Despite recuperation, the heat requirement is very high and can be significantly reduced by lowering the maximum temperature in the pasteurizer. The current practice of calculating the lethal heat effect is based on the so-called beer formula using a globalized z-value for the temperature dependence of the inactivation. The premise experiments here is that for products containing sugar, such as malt beer, yeast cells pose the greatest danger. Therefore, the D values at various temperatures and the z values of three of the Krombacher Brewery's own yeasts (bottom-fermenting and top-fermenting) were determined in the laboratory using the capillary method. In a challenge test in the brewery, bottles with different products were inoculated with these yeasts and samples were taken from the industrial pasteurizer every two minutes and examined for viable cell counts. Accordingly, using specific D/z values, precise pasteurization can be achieved, the treatment temperature can be reduced to 55° C and 20-25% of energy can be saved.}},
  author       = {{Nolte, Jannik and Hense, Ludger  and Weishaupt, Imke and Schneider, Jan}},
  keywords     = {{pasteurization, D value, z-value, heat energy savings, large scale trials, biological stability, yeast}},
  location     = {{Lille}},
  title        = {{{How do you turn a shotgun into a precision rifle - significant heat savings through the use of kinetic laboratory data (D/z values) in large-scale pasteurization}}},
  year         = {{2024}},
}

@phdthesis{13335,
  abstract     = {{The process of thermal preservation of liquid foods is a safety-relevant process step in the processing of products such as fruit juices and is associated with a high-energy expenditure and safety margin. There are already various approaches to improve this conventionally managed process step in terms of product and resource preservation. Compared to these novel technologies, the use of real-time process analytics offers great potential to improve already existing process plants by implementing inline capable process analytical tools. This allows direct control of the reactions taking place and changes during the running process. Instead of post process, random product control, quality control during the process can be made rendered. The chemical and pharmaceutical industry serves as a reference industry for the use of process analytical tools, although the reactions and product matrices are less complex. In the food industry, on the other hand, there is a greater variation in raw materials and intermediate products. In addition, a large number of reactions can take place in parallel within a process, and the physical states and properties of the individual components can vary. A uniform set of rules for the use of process analytical tools does not exist here. Each product, each process provides its own research potential, so that a large research gap opens up in the area of the food industry.
In order to contribute to closing this gap, this thesis presents a novel approach to improve the process of pasteurization of liquid food. For fruit juices as an application, near infrared spectroscopy in combination with chemometric methods was applied to make the process more product specific. Based on known weaknesses of the process, the relevant aspects for a product-specific treatment were identified. In the further course, the suitability of near infrared spectroscopy as a process analytical tool in the process of pasteurization was verified. Moreover, it was investigated whether a sufficiently accurate identification of the product type as well as the microbiologically relevant properties can be achieved by the application of chemometric methods. In the course of this, the suitability of the measurement methodology was confirmed and solutions were established for any process influences. The product classification and description of the microbiologically relevant parameters extract content and pH value were also implemented with sufficient accuracy. Knowing the destruction kinetics of relevant microorganisms, the product-specific determination of target values for the necessary lethal heat input could be realized. In addition, an analysis of the actual values was carried out on the basis of a chemometric regression method by inferring the microbiological pasteurization effect through the chemical reaction of acid hydrolytic sucrose degradation by means of the indirect approach. This required knowledge of the chemical reaction kinetics and mahematical modeling of the degradation behavior. The novel approach could be confirmed by calculations using results from off-line analysis, whereas the use of near infrared spectroscopy as an inline method still revealed potential for optimization with respect to measurement accuracies.
In summary, the results of this work provide a promising opportunity to make conventional processes for the preservation of liquid foods more product-specific by using near-infrared spectroscopy as an inline-capable and multimodal sensor technique, leading to an increase in process efficiency and product quality.}},
  author       = {{Weishaupt, Imke}},
  keywords     = {{fruit juice pasteurization, near infrared spectroscopy, process optimization, multivariate statistics, inline process analytics, Fruchtsaftpasteurisation, Prozessoptimierung, Nahinfrarotspektroskopie, multivariate Statistik, Inline-Prozessanalytik}},
  pages        = {{144}},
  publisher    = {{Technische Universität Berlin}},
  title        = {{{Near infrared spectroscopy as inline analytical tool to optimize the pasteurization process of liquid foods}}},
  doi          = {{https://doi.org/10.14279/depositonce-17804}},
  year         = {{2023}},
}

@misc{8447,
  author       = {{Schwarzer, Knut and Müller, Ulrich and Schneider, Jan}},
  keywords     = {{Pasteurization, minimal processing}},
  location     = {{Madrid}},
  title        = {{{Rethink Beer Pasteurization – Safety, Sustainability and Quality}}},
  year         = {{2022}},
}

@article{5425,
  abstract     = {{The feasibility of inline classification and characterization of seven fruit juice varieties was investigated by the application of near-infrared spectroscopy (NIRS) combined with chemometrics. The findings are intended to be used to optimize the flash pasteurization of liquid foods. More precise information of the kind of product in real time had to be achieved to enable a more product-specific process. Using the method of partial least squares discriminant analysis, the fruit juice varieties were classified, showing a classification rate of 100% regarding an internal and 69% regarding an external test sets. A characterization by the extract content, pH value, turbidity, and viscosity was made by fitting a partial least squares regression model. The percentage prediction error of the pH value was <3% for internal and external test sets, and for the Brix value prediction errors were about 4% (internal) and 20% (external). The parameters viscosity and turbidity were found to be unsuitable. Despite this, the strategy applied to gain more product-specific information in real time showed to be feasible. By linking the results to a database containing potentially harmful microorganisms for various types of fruit juices, a more product-specific calculation of the necessary heat input can be performed. To demonstrate the practical relevance, a comparison between conventional and product-adapted process control was performed using two fruit varieties as examples in case of Alicyclobacillus acidoterrestris. Thus, with more accurate product information, achieved through the use of NIRS with chemometrics, a more precise calculation of the heat input can be achieved.}},
  author       = {{Weishaupt, Imke and Neubauer, Peter and Schneider, Jan}},
  issn         = {{2048-7177}},
  journal      = {{Food Science & Nutrition}},
  keywords     = {{flash pasteurization, fruit juice characterization and classification, inline near-infrared spectroscopy, multivariate data analysis}},
  number       = {{3}},
  pages        = {{800--812}},
  publisher    = {{Wiley}},
  title        = {{{Near-infrared spectroscopy for the inline classification and characterization of fruit juices for a product-customized flash pasteurization}}},
  doi          = {{ https://doi.org/10.1002/fsn3.2709}},
  volume       = {{10}},
  year         = {{2022}},
}

@misc{7981,
  abstract     = {{The main purpose of bovine colostrum, being the milk secreted by a cow after giving birth, is to transfer passive immunity to the calf. The calves have an immature immune system as they lack immunoglobulins (Igs). Subsequently, the supply of good quality bovine colostrum is required. The quality of colostrum is classified by low bacterial counts and adequate Ig concentrations. Bacterial contamination can contain a variety of human pathogens or high counts of spoilage bacteria, which has become more challenging with the emerging use of bovine colostrum as food and food supplements. There is also a growing risk for the spread of zoonotic diseases originating from bovines. For this reason, processing based on heat treatment or other feasible techniques is required. This review provides an overview of literature on the microbial quality of bovine colostrum and processing methods to improve its microbial quality and keep its nutritional values as food. The highlights of this review are as follows: high quality colostrum is a valuable raw material in food products and supplements; the microbial safety of bovine colostrum is increased using an appropriate processing-suitable effective heat treatment which does not destroy the high nutrition value of colostrum; the heat treatment processes are cost-effective compared to other methods; and heat treatment can be performed in both small- and large-scale production.}},
  author       = {{Fasse, Sylvia and Alarinta, Jarmo and Frahm, Björn and Wirtanen, Gun}},
  booktitle    = {{Dairy}},
  issn         = {{2624-862X }},
  keywords     = {{bovine colostrum, bacteria, pathogens, probiotic bacteria, cost-effective processing, heat treatment, pasteurization, contamination control, immunoglobulins, enzymes}},
  number       = {{4}},
  pages        = {{556--575}},
  publisher    = {{MDPI}},
  title        = {{{Bovine Colostrum for Human Consumption - Improving Microbial Quality and Maintaining Bioactive Characteristics through Processing}}},
  doi          = {{10.3390/dairy2040044}},
  volume       = {{2}},
  year         = {{2021}},
}

@article{6839,
  abstract     = {{Pasteurization is a crucial processing method in the food industry to ensure the safety of consumables. A major part of contemporary pasteurization processes involves using flash pasteurizer systems, where liquids are pumped through a pipe system to heat them for a predefined time. Accurately monitoring the amount of heat treatment applied to a product is challenging. This monitoring helps ensure that the correct heat impact (expressed in pasteurization units) is applied, which is commonly calculated as a product of time and temperature, taking achievability of the inactivation of the microorganisms into account. The state-of-the-art method involves a calculation of the applied pasteurization units using a one-point temperature measurement and the holding time for this temperature. Concerns about accuracy lead to high safety margins, reducing the quality of the pasteurized product. In this study, the applied pasteurization level was estimated using regression models trained with NIR spectroscopy data collected while pasteurizing fruit juices of different types and brands. Several conventional regression models were trained in combination with different preprocessing methods, including a novel prediction outlier detection method. Generalized juice models trained with the concatenated data of all types of juices demonstrated cross-validated scores of RMSECV ∼2.78 ± 0.09 and r<jats:sup>2</jats:sup> 0.96 ± 0.01, while separate juice models displayed averaged cross-validated scores of RMSECV ∼1.56 ± 0.04 and r<jats:sup>2</jats:sup> 0.98 ± 0.01. Thus, the model accuracy ±10–30 % is well within the standard safety margins. }},
  author       = {{Sürmeli, Baris Gün and Weishaupt, Imke and Schwarzer, Knut and Moriz, Natalia and Schneider, Jan}},
  issn         = {{1751-6552}},
  journal      = {{Journal of Near Infrared Spectroscopy}},
  keywords     = {{Beverage pasteurization, heat impact control, prediction outlier elimination}},
  number       = {{6}},
  pages        = {{339--351}},
  publisher    = {{Sage Publishing}},
  title        = {{{Heat impact control in flash pasteurization by estimation of applied pasteurization units using near infrared spectroscopy}}},
  doi          = {{10.1177/09670335211057233}},
  volume       = {{29}},
  year         = {{2021}},
}

@misc{5423,
  abstract     = {{Preservation of juices is essential to obtain microbial safe products. There are various established methods as pasteurization. Heretofore, only the kinetic figures of microbial inactivation were considered but not those of reaction impairing the chemical quality. For a gentler processing, knowledge of the kinetics of relevant chemical conversion reactions is necessary. 5-(Hydroxymethyl)-furfural (HMF) formation and the color change of juices are important attributes. The non-isothermal Rhim method was used to determine the activation energy and pre-exponential factor for HMF formation in different juices and an isothermal method for the reaction order. Values for the activation energy from 133 to 303 kJ/mol were obtained with a zeroth reaction order. A correlation between HMF and the color change could be found. Based on the kinetic figures, lines with equal effects for the chemical changes and for the lethal effect on microorganisms were calculated. Time-temperature settings for the gentlest treatment could be found.}},
  author       = {{Katsch, Linda and Methner, Frank-Jürgen and Schneider, Jan}},
  booktitle    = {{International Journal of Food Engineering }},
  issn         = {{1556-3758}},
  keywords     = {{absorption at 420 nm, HMF, kinetic figures, line of equal effect, pasteurization.}},
  number       = {{9}},
  pages        = {{703--713}},
  publisher    = {{Walter de Gruyter GmbH}},
  title        = {{{Kinetic studies of 5-(Hydroxymethyl)-furfural formation and change of the absorption at 420 nm in fruit juices for the improvement of pasteurization plants }}},
  doi          = {{https://doi.org/10.1515/ijfe-2020-0324}},
  volume       = {{17}},
  year         = {{2021}},
}

@article{5424,
  abstract     = {{Near infrared spectroscopy in combination with a transflection probe was investigated as inline measurement in a continuous flash pasteurizer system with a sugar-water model solution. Robustness and reproducibility of fluctuations of recorded spectra as well as trueness of the chemometric analysis were compared under different process parameter settings. Variable parameters were the flow rate (from laminar flow at 30 L/h to turbulent flow at 90 L/h), temperature (20 to 100 degrees C) and the path length of the transflection probe (2 and 4 mm) while the pressure was kept constant at 2.5 bar. Temperature and path length were identified as the most affecting parameters, in case of homogenous test medium. In case of particle containing systems, the flow rate could have an impact as well. However, the application of a PLS model, which includes a broad temperature range, and the correction of prediction results by applying a polynomial regression function for prediction errors, was able to compensate these effects. Also, a path length of 2 mm leads to a higher accuracy. The applied strategy shows that by the identification of relevant process parameters and settings as well as the establishment of a compensation strategy, near infrared spectroscopy is a powerful process analytical tool for continuous flash pasteurization systems.}},
  author       = {{Weishaupt, Imke and Zimmer, Manuel and Neubauer, Peter and Schneider, Jan}},
  isbn         = {{0022-1147}},
  issn         = {{1750-3841}},
  journal      = {{Journal of Food Science}},
  keywords     = {{flash pasteurization, inline near infrared spectroscopy, multivariate data analysis, process condition influences, sugar-water-solution model beverage}},
  number       = {{7}},
  pages        = {{2020 -- 2031}},
  title        = {{{Model based optimization of transflection near infrared spectroscopy as a process analytical tool in a continuous flash pasteurizer}}},
  doi          = {{10.1111/1750-3841.15307}},
  volume       = {{85}},
  year         = {{2020}},
}