Organic food processing: a framework for concept,starting definitions and evaluation

In 2007 EU Regulation (EC) 834/2007 introduced principles and criteria for organic food processing. These regulations have been analysed and discussed in several scientific publications and research project reports. Recently, organic food quality was described by principles, aspects and criteria. These principles from organic agriculture were verified and adapted for organic food processing. Different levels for evaluation were suggested. In another document, underlying paradigms and consumer perception of organic food were reviewed against functional food, resulting in identifying integral product identity as the underlying paradigm and a holistic quality view connected to naturalness as consumers' perception of organic food quality. In a European study, the quality concept was applied to the organic food chain, resulting in a problem, namely that clear principles and related criteria were missing to evaluate processing methods. Therefore the goal of this paper is to describe and discuss the topic of organic food processing to make it operational. A conceptual background for organic food processing is given by verifying the underlying paradigms and principles of organic farming and organic food as well as on organic processing. The proposed definition connects organic processing to related systems such as minimal, sustainable and careful, gentle processing, and describes clear principles and related criteria. Based on food examples, such as milk with different heat treatments, the concept and definitions were verified. Organic processing can be defined by clear paradigms and principles and evaluated according criteria from a multidimensional approach. Further work has to be done on developing indicators and parameters for assessment of organic food quality. © 2013 Society of Chemical Industry     

Biomechanical and morphological stability of acellular scaffolds for tissue-engineered heart valves depends on different storage conditions

Currently available bioprosthetic heart valves have been successfully used clinically; however, they have several limitations. Alternatively, tissue-engineering techniques can be used. However, there are limited data concerning the impact of storage conditions of scaffolds on their biomechanics and morphology. The aim of this study was to determine the effect of different storage conditions on the biomechanics and morphology of pulmonary valve dedicated for the acellular scaffold preparation to achieve optimal conditions to obtain stable heart valve prostheses. Scaffold can then be used for the construction of tissue-engineered heart valve, for this reason evaluation of these parameters can determine the success of the clinical application this type of bioprosthesis. Pulmonary heart valves were collected from adult porcines. Materials were divided into five groups depending on the storage conditions. Biomechanical tests were performed, both the static tensile test, and examination of viscoelastic properties. Extracellular matrix morphology was evaluated using transmission electron microscopy and immunohistochemistry. Tissue stored at 4?°C exhibited a higher modulus of elasticity than the control (native) and fresh acellular, which indicated the stiffening of the tissue and changes of the viscoelastic properties. Such changes were not observed in the radial direction. Percent strain was not significantly different in the study groups. The storage conditions affected the acellularization efficiency and tissue morphology. To the best of our knowledge, this study is the first that attributes the mechanical properties of pulmonary valve tissue to the biomechanical changes in the collagen network due to different storage conditions. Storage conditions of scaffolds for tissue-engineered heart valves may have a significant impact on the haemodynamic and clinical effects of the used bioprostheses.

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Influence of Specific Processing Conditions and Aliphatic-Aromatic Copolyester on Polylactide Properties

This study reports the influence of aliphatic-aromatic copolyesters (AAC) on selected polylactide (PLA) properties. Processing, mechanical, and thermal properties were determined. In addition, we examined changes occurring in the surface geometrical structure of sample fractures. It was found that PLA as modified with AAC exhibited enhanced impact strength and melt flow rate, unaffected elongation at break, and reduced tensile strength and elasticity modulus. The results also demonstrate the plasticizing properties of AAC, which improved PLA processing and its thermal stability. We also observed insufficient adhesion at the interface between the two components, as well as heterogeneity of the obtained material.     

Global Changes of 5-mC/5h-mC Ratio and Methylation of Adiponectin and Leptin Gene in Placenta Depending on Mode of Delivery

It was suggested that the epigenetic alterations of the placenta are associated with obesity, as well as the delivery mode. This study aimed to assess the effect of maternal outcome and delivery procedure on global placental DNA methylation status, as well as selected 5’-Cytosine-phosphate-Guanine-3’ (CpG) sites in ADIPOQ and LEP genes. Global DNA methylation profile in the placenta was assessed using the 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) ratio evaluated with the ELISA, followed by target gene methylation patterns at selected gene regions which were determined using methylation-specific qPCR in 70 placentas from healthy, pregnant women with single pregnancy. We found no statistically significant differences in 5-mC/5-hmC ratio between intrapartum cesarean sections (CS) and vaginal deliveries (p = 0.214), as well as between elective cesarean sections and vaginal deliveries (p = 0.221). In intrapartum cesarean sections, the ADIPOQ demethylation index was significantly higher (the average: 1.75) compared to elective cesarean section (the average: 1.23, p = 0.010) and vaginal deliveries (the average: 1.23, p = 0.011). The LEP demethylation index did not significantly differ among elective CS, intrapartum CS, and vaginal delivery groups. The demethylation index of ADIPOQ correlated negatively with LEP in the placenta in the vaginal delivery group (r = −0.456, p = 0.017), but not with the global methylation. The methylation of a singular locus might be different depending on the mode of delivery and uterine contractions. Further studies should be conducted with locus-specific analysis of the whole genome to detect the methylation index of specific genes involved in metabolism.     

Physicochemical characterisation of quince fruits for industrial use: yield,turbidity, viscosity and colour properties of juices

In this study, were compared and characterised some of the physicochemical quality parameters as yield, turbidity and its stability of turbidity, viscosity, colour, dry matter, total soluble solid (TSS), total titratable acidity (TTA), pH parameters of quince juices accessions as well as different 11 cultivars before and after 6 months storage time at 4 and 30 °C. Quince fruits were used for the first time to prepare juices. The effect of different cultivars on juice yield was observed. The content of dry matter, TSS, TTA and turbidity value, stability of turbidity, viscosity, and colour in the analysed juices were depended not only on cultivars but also on storage conditions. Juices analysed were characterised by a significant variation in turbidity value and their stability and by a slight variation in viscosity. This information may be used by the juice industry as a starting point for producers of natural attractive juices from quince fruits.     

Bioactive compounds and sensory attributes of sour cherry puree sweetened with natural sweeteners

The aim of this study was to describe a phytochemical profile, including phenolic compounds, antioxidant capacity, colour and sensory quality attributes (colour, aroma, consistency, sweetness intensity and desirability) of a sour cherry puree (SCP) supplemented with different natural sweeteners. Supplementation of SCP with the sweeteners only slightly affected polyphenol content, which was by 9% (SCP with steviol glycosides) to 26% (SCP with erythritol) lower than in pure SCP. Furthermore, the products with natural sweeteners were characterised for the lowest antioxidant activity than the SCP sample, especially in SCP with erythritol and xylitol. In addition to having high content of polyphenols and high antioxidant activity, these products were also attractive to consumers, especially when supplemented with xylitol, palm sugar or sucrose, but not with Luo Han Kuo fruit, which was found unacceptable. The results showed that most of the obtained SCPs had very promising and interesting phytochemical properties and sensory profiles.     

An analysis of the numerical model influence on the ground temperature profile determination

The estimation of the ground temperature profile with respect to the depth and time is the key issue in many engineering applications which use the ground as a source of thermal energy. In the present work, the influence of the model components on the calculated ground temperature distribution has been analysed in order to develop an accurate and robust model for the prediction of the ground temperature profile. The presented mathematical model takes into account all the key phenomena occurring in the soil and on its top surface. The impact of individual model elements on the temperature of the soil has been analysed. It has been found that the simplest models and the most complex model result in a similar temperature variation over the simulation period, but only at a low depth. A detailed analysis shows that a larger depth requires more complex models and the calculation with the use of simple models results in an incorrect temperature and a theoretical COP estimation.