Search

Taste as an eating quality factor of beef can be influenced by the selection of the raw material and aging method. The metabolic changes of different breeds during aging were analyzed in wet-aged and dry-aged beef up to 28 days of aging using samples from the M. longissimus thoracis et lumborum of the Simmental and Black-and-White breeds by 1H NMR spectroscopy. Breed affected the metabolome of beef samples before and during the aging of beef. The concentration of 24 of the 30 metabolites differed significantly (P P l-carnitine) varied significantly (P

Food authenticity in the field of food dyes can be interpreted as the correctness of the coloring ingredients indicated. The Rapid UV/vis Spectroscopic Dye Authentication Assay (RaSDAY) presented in this work was used to verify the authenticity of water-soluble reddish colorings for food use. RaSDAY includes the processing of samples under different experimental conditions with pH variations and heat exposure. The absorbances measured are analyzed by principal component analysis and a k-nearest neighbors algorithm. As a result, classification of anthocyanins, betalains, and carmine and the detection of Monascus pigments, undeclared artificial food dyes, and reactive textile azo dyes can be performed by utilizing a rapid screening method. In 17 out of 20 samples of coloring food additives that were included in this work, reactive dyes, unpermitted Monascus pigments, and artificial food dyes were detected using the developed method. "Reactive Red 120", "Reactive Red 195", and "Reactive Red 198" were identified by subsequent 1H NMR spectroscopy in eight of those samples.

The aging of beef affects the metabolome and, thus, its quality, such as taste or tenderness. In addition to the aging method, intrinsic factors, such as breed, feed and muscle type, also have an effect on beef's metabolome. It is not known yet whether the position of the sampling in large muscles also has an influence on beef's metabolome and its aging outcome. The effect of the sampling position in M. longissimus dorsi as a large muscle was investigated in dry-aged and wet-aged beef over an aging period of 28 days. In this study, we analyzed 360 samples out of the entire length of M. longissimus dorsi of 18 'Simmental' young bulls by

The purpose of this review is to provide an overview of the current knowledge about proteomic and metabolic changes in beef, the microbiological alteration postmortem and during aging, and observe the influence on beef quality parameters, such as tenderness, taste and flavor. This review will also focus on the different aging types (wet- and dry-aging), the aging or postmortem time of beef and their effect on the proteome and metabolome of beef. The Ca2+ homeostasis and adenosine 5’-triphosphate breakdown are the main reactions in the pre-rigor phase. After rigor mortis, the enzymatic degradation of connective tissues and breakdown of energy metabolism dominate molecular changes in beef. Important metabolic processes leading to the formation of saccharides, nucleotides, organic acids (e.g. lactic acid), creatine and fatty acids are considered in this context as possible flavor precursors or formers of beef flavor and taste. Flavor precursors are substrates for lipid oxidation, Strecker degradation and Maillard reaction during cooking or roasting. The findings presented should serve as a basis for a better understanding of beef aging and its molecular effects and are intended to contribute to meeting the challenges of improving beef quality.

The meat industry is typically using a mixture of fresh and frozen meat batters for minced meat production. Our goal was to find the exact threshold for fresh to frozen meat ratio capable of controlling the meat temperature during processing, but without having an adverse effect on the sensory quality of minced pork. To achieve this, the percentage of frozen meat used for the minced pork production was increased from 0% (control) to 50% (maximum) in 10% increments. To keep the minced meat temperature in control and make the processing resistant to fat smearing, the addition of 30% of frozen meat to the meat batter is sufficient. The soluble protein content, instrumental cutting force, and the sensory perceived firmness, juiciness, and inner cohesion were not affected by the addition of frozen meat. However, it has contributed to a significant increase of the drip loss and the amount of non-intact cells (ANIC). With the addition of frozen meat into the minced pork, the compliance to ANIC regulation by the German regulatory authorities is technologically (practically) almost impossible.

Food authenticity in the field of food dyes can be interpreted as the correctness of the coloring ingredients indicated. The Rapid UV/vis Spectroscopic Dye Authentication Assay (RaSDAY) presented in this work was used to verify the authenticity of water-soluble reddish colorings for food use. RaSDAY includes the processing of samples under different experimental conditions with pH variations and heat exposure. The absorbances measured are analyzed by principal component analysis and a

The tenderness and taste of beef is improved by either dry- or wet-aging or a combination of both. The objective was to develop a validated method for detecting differences in the polar fraction of metabolome in dry-aged and wet-aged beef over the aging time and quantifying the metabolites of interest by

The reduction of bacteria-caused disease transmission gains importance in medicine as well as in areas of public life. As part of a project, a bio-based compound was developed which combines the advantages of plastics processing and the natural bactericidal effect of heartwood. A Polylactide polymer and bactericidal pine heartwood chips were mixed to a compound and injection molded into specimens, to create a plastic material with antimicrobial ingredients. An aim of this work was to preserve the bactericidal ingredients of pine heartwood chips (Pinus sylvestris) during compounding and injection molding into Polylactide wood compound specimens. Additionally, it was necessary to ensure the efficiency of the bactericidal ingredients especially at the surface of the specimens and the increase of the mechanical compound properties. Therefore, the specimens were tested with an antibacterial test method based on the ISO 22196:2011. Influences of different conditions such as temperature, chip size and chip content on the antimicrobial efficacy and mechanical properties were tested using a Design of Experiment. The specimens were tested for antibacterial activity, Charpy impact strength, surface hardness, Young’s modulus and yield strength. The results show significant dependencies between varied parameters and measured material properties.

The tenderness and taste of beef is improved by either dry- or wet-aging or a combination of both. The objective was to develop a validated method for detecting differences in the polar fraction of metabolome in dry-aged and wet-aged beef over the aging time and quantifying the metabolites of interest by 1H NMR spectroscopy using beef. Sixty strip loin (M. longissimus dorsi) samples aged in different ways (wet-aging vs. dry-aging) and aging times (0, 7, 14, 21, 28 days) were analyzed. The aging type could be defined by linear discriminant analysis with an accuracy of 95%. Ten (lactic acid, alanine, methionine, fumaric acid, inosine, inosine monophosphate, creatine, betaine, carnosine and hypoxanthine) out of eighteen metabolites differ significantly (p 0.7

To get a deeper insight into the molecular interactions between sucrose and lecithin’s different phospholipids (PL), the impact of soybean and sunflower lecithin on sucrose surfaces ground in liquid cocoa butter was studied. Therefore, flow properties of the cocoa-butter based suspension, immobilized cocoa butter content as well as detailed PL analysis concerning layer thickness and PL content was related to sucrose surface topographies and force spectroscopy measurements performed by atomic force microscopy (AFM). We found that adsorption of PL from soy lecithin to sucrose resulted in thinner layers with a larger total PL coverage, whereas PL from sunflower adsorbed in smaller amounts but resulted in thicker layers. So, PL covering of the surface is not homogeneous. As a consequence, immobilized fat content after adsorption of PL from soy was found to be smaller than for PL from sunflower lecithin. Also the yield value for suspensions containing soy PL was somewhat lower than for PL from sunflower lecithin. These changes could successfully be traced back to the microscopic scale of the sucrose particle surfaces. AFM surface properties were found to be highly influenced by adsorption of emulsifier molecules in the way that topography dramatically changed and also adhesion properties highly differed after application of soy or sunflower lecithin. By linking these molecular properties of PL from different origin to their behavior at molecular level and to the resulting macroscopic effects, the outcome of this study confirmed some essential differences between the applications of soy and sunflower lecithin with respect to chocolate manufacturing.

Due to health-beneficial effects of polyphenols, their stability and bioaccessibility in strawberry puree as influenced by processing (thermal, pulsed electric field (PEF), high pressure processing (HPP)) and by combination with relatively protein-rich vegetable juice (kale) was investigated. Soluble strawberry anthocyanins decreased in the presence of kale, in a processing-dependent manner, likely due to interactions with kale proteins. In the strawberry-water-system, polyphenols increased after processing due to increased extraction, especially after thermal and PEF, while in the mix anthocyanins increased especially after HPP and PEF. Anthocyanin structure affected the ratio of free anthocyanins after the interaction. During gastric digestion, an increase in bioaccessible anthocyanins was observed, while during intestinal digestion it strongly diminished. Thermal, PEF and formulation of the mix reduced soluble protein fractions, as observed by decreasing SDS-PAGE band intensity. The proteins were easily digestible and after 15 min of gastric digestion, no bands appeared with an increase in TCA soluble peptides. Industrial relevance With the increase in health awareness and the changing on-the-go lifestyle, consumers demand convenient fruit and vegetable-based products with high nutritional and health-promoting content. Thus, utilization of alternative processing with minimal impact on the quality of fruit and vegetable juices is considered as a promising tool to deliver such high nutritional products, however, little is known about their effect on multi-component juice systems, where interactions between the different components can occur. Strawberries are the most commonly consumed berry type, delivering high quantities of polyphenols and therefore a representative polyphenol-rich model system. Kale is gaining increasing attention due to the nutritional profile, above others, it contains relatively (to other fruits and vegetables) high protein content, and therefore displays an interesting vegetable-based protein-rich model. A more in-depth understanding of the effect of alternative processing on polyphenol-protein interactions in these increasingly popular mixed systems (green smoothies) and the digestive fate of these potentially health-beneficial compounds is studied and provides new insights into designing functional products attractive for consumers.

Polyglycerol polyricinoleate (PGPR) often is used as emulsifier in chocolate, but only little is known on the specific interactions between sucrose particles, cocoa butter and PGPR molecules. The most remarkable effect of PGPR on lipophilic suspensions is the enormous decrease in yield value compared to soy lecithin which is not yet understood. A combination of atomic force microscopy (AFM), scanning electron microscopy (SEM), rheological measurements and analysis of immobilized fat content was used to reveal more details on the mechanism of function of PGPR. It was found that this mechanism is completely different to the one of soy lecithin. On sucrose particle surfaces, PGPR concentration was determined to 0.18 mg/m 2 whereas soy lecithin coverage was calculated to 2.69 mg/m 2 . The interfacial layer obtained by washing separated sucrose particles with acetone contains 83.6 g/100 g cocoa butter which had been immobilized together with or by PGPR molecules. This interaction plays a major role in the mechanism of function of PGPR as an emulsifier. Weakly bound structures consisting of PGPR and cocoa butter were found to form pillow-like structures. They act as spacers between the sucrose particles and reduce particle-particle interaction so that less structure can be built up. That is why flow can be induced very easily. In addition, as particles move along together very well due to steric hindrance of these pillow-like structures, viscosity of the suspension remains low.

The incidence of chronic diseases increases with advancing age of the population. A commonly discussed cause of chronic diseases is oxidative stress, which occurs in the body when there is an imbalance between the formation and inactivation of so-called reactive oxygen species (ROS). Epidemiological data suggest that a 'healthy diet', with a high content of flavonoids indicates preventive properties and correlates with an inverse effect with respect to the risk of chronic diseases. Berries (especially bilberries, Vaccinium myrtillus L.) are an important source of these flavonoids. In this study, we investigated, in vitro, the antioxidative properties of fractions obtained from a commercially available anthocyanin-rich bilberry extract (BE). As markers for antioxidative activity, the intracellularly generated ROS levels, oxidative DNA damage, and total glutathione (tGSH) levels were determined in the human colon cell lines Caco-2 and HT-29. In Caco-2 cells, the ROS levels and, in both cell lines, the oxidative DNA damage, were significantly reduced in the presence of the original BE and phenolcarbonic acid-rich fraction. Total GSH levels were slightly increased after pretreatment with BE, phenolcarbonic acid and the polymeric fractions, but not with the anthocyanin fraction. In summary, the BE and the therefrom-isolated phenolcarbonic acid-rich fraction, showed the most potent antioxidative activity whereas the polymeric and anthocyanin-rich fraction, in total, were less active.

A novel membrane chromatographic method with a membrane adsorber (Sartobind S) has been developed on the laboratory scale that allows a fractionation of bilberry (Vaccinium myrtillus) constituents into the following three groups of polyphenols: anthocyanins, copigments, and polymers. By using this methodology, a pure anthocyanin fraction free of other copigments and polymeric phenols can be obtained. Using this approach, it provides fractions allowing a more thorough testing of the biological effects of the individual groups of bilberry polyphenols as well as the study of possible synergistic effects between these different groups of bioactive constituents from bilberry.