Bacillus thermoamylovorans – A new threat to the dairy industry – A review

Bacillus thermoamylovorans is a newly described spore forming bacterium emerging in the dairy industry. There is an increasing threat of B. thermoamylovorans contamination, not only in food ingredients and raw milk, but also in sterilised milk and dairy products. Animal feed, processing equipment, and farm environments are potential entry points for contamination of milk with B. thermoamylovorans. The ability of B. thermoamylovorans to produce lipolytic and β-galactosidase enzymes is linked to food spoilage. B. thermoamylovorans spores have a heat resistance comparable with that of the spores of Bacillus sporothermodurans, indicating the potential to survive ultra-high temperature treatments. However, despite the rise in reports of the isolation of B. thermoamylovorans from dairy samples, there have been few reports on the characterisation of these bacteria. The origin, characteristics and potential issues resulting from B. thermoamylovorans in the dairy industry and potential methods of control are discussed in this review.     

SARS – Pandemie und Emerging Disease

The SARS-epidemic of 2002/2003 with worldwide 8.096 cases and 774 fatalities was the first pandemia of the 21^st century. SARS, the severe acute respiratory syndrome, arose in southern China and spread from Southeast-Asia finally over all five continents. It caused heavy pneumonia with pulmonal failure and enteric involvement in man. The causative agent was a novel coronavirus (SARS-CoV), which was transmitted from bats to small carnivores and from them to man. The mutations of the viral receptor gene thus allowed the infection of man and the transmission from man to man. The SARS-pandemia can therefore be regarded as a model of an emerging disease. Eingegangen: 21. Mai 2008     

Gelation of gellan – A review

Gellan is an anionic extracellular bacterial polysaccharide discovered in 1978. Acyl groups present in the native polymer are removed by alkaline hydrolysis in normal commercial production, giving the charged tetrasaccharide repeating sequence: → 3)-β-d-Glcp-(1 → 4)-β-d-GlcpA-(1 → 4)-β-d-Glcp-(1 → 4)-α-l-Rhap-(1 →. Deacylated gellan converts on cooling from disordered coils to 3-fold double helices. The coil–helix transition temperature (T_m) is raised by salt in the way expected from polyelectrolyte theory: equivalent molar concentrations of different monovalent cations (Group I and Me₄N⁺) cause the same increase in T_m; there is also no selectivity between different divalent (Group II) cations, but divalent cations cause greater elevation of T_m than monovalent. Cations present as counterions to the charged groups of the polymer have the same effect as those introduced by addition of salt. Increasing polymer concentration raises T_m because of the consequent increase in concentration of the counterions, but the concentration of polymer chains themselves does not affect T_m. Gelation occurs by aggregation of double helices. Aggregation stabilises the helices to temperatures higher than those at which they form on cooling, giving thermal hysteresis between gelation and melting. Melting of aggregated and non-aggregated helices can be seen as separate thermal and rheological processes. Reduction in pH promotes aggregation and gelation by decreasing the negative charge on the polymer and thus decreasing electrostatic repulsion between the helices. Group I cations decrease repulsion by binding to the helices in specific coordination sites around the carboxylate groups of the polymer. Strength of binding increases with increasing ionic size (Li⁺ < Na⁺ < K⁺ < Rb⁺ < Cs⁺); the extent of aggregation and effectiveness in promoting gel formation increase in the same order. Me₄N⁺ cations, which cannot form coordination complexes, act solely by non-specific screening of electrostatic repulsion, and give gels only at very high concentration (above ∼0.6 M). At low concentrations of monovalent cations, ordered gellan behaves like a normal polymer solution; as salt concentration is increased there is then a region where fluid “weak gels” are formed, before the cation concentration becomes sufficient to give true, self-supporting gels. Aggregation and consequent gelation with Group II cations occurs by direct site-binding of the divalent ions between gellan double helices. High concentrations of salt or acid cause excessive aggregation, with consequent reduction in gel strength. Maximum strength with divalent cations comes at about stoichiometric equivalence to the gellan carboxylate groups. Much higher concentrations of monovalent cations are required to attain maximum gel strength. The content of divalent cations in commercial gellan is normally sufficient to give cohesive gels at polymer concentrations down to ∼0.15 wt %. Gellan gels are very brittle, and have excellent flavour release. The networks are dynamic: gellan gels release polymer chains when immersed in water and show substantial recovery from mechanical disruption or expulsion of water by slow compression. High concentrations of sugar (∼70 wt % and above) inhibit aggregation and give sparingly-crosslinked networks which vitrify on cooling. Gellan forms coupled networks with konjac glucomannan and tamarind xyloglucan, phase-separated networks with kappa carrageenan and calcium alginate, interpenetrating networks with agarose and gelling maltodextrin, and complex coacervates with gelatin under acidic conditions. Native gellan carries acetyl and l-glyceryl groups at, respectively, O(6) and O(2) of the 3-linked glucose residue in the tetrasaccharide repeat unit. The presence of these substituents does not change the overall double helix structure, but has profound effects on gelation. l-Glyceryl groups stabilise the double helix by forming additional hydrogen bonds within and between the two strands, giving higher gelation temperatures, but abolish the binding site for metal ions by changing the orientation of the adjacent glucuronate residue and its carboxyl group. The consequent loss of cation-mediated aggregation reduces gel strength and brittleness, and eliminates thermal hysteresis. Aggregation is further inhibited by acetyl groups located on the periphery of the double helix. Gellan with a high content of residual acyl groups is available commercially as “high acyl gellan”. Mixtures of high acyl and deacylated gellan form interpenetrating networks, with no double helices incorporating strands of both types. Gellan has numerous existing and potential practical applications in food, cosmetics, toiletries, pharmaceuticals and microbiology.     

Nutrition and Health – Transforming Research Traditions

In this contribution, we show that current scientific methodologies used in nutrition science and by regulatory agencies, such as the randomized control trial, limit our understanding of nutrition and health as they are to crude to capture the subtle pleiotropic nature of most nutrients. Thereby, regulatory agencies such as the European Food Safety Authority curb the development of scientific knowledge and industrial innovations within the nutritional field. In order to develop insights into the health impact of certain food and food-components, we need to realize that health is adaptation set within a homeostatic range. Increased performance of health, i.e., the maximum stimulation of health, typically seems 30–60% greater than the control group, with a width of no more than about a factor of ten, clarifying the difficulty of documenting responses of food-endogenous components within the homeostatic range of healthy people. A strategy to record subtle responses of food components is the summation of procentual effects of relevant health outcomes. We illustrate this approach with the action of flavanols on vascular health, specifically endothelial function.     

Benzol in Lebensmitteln – ein Überblick

Benzene is an environmental contaminant and humans are mainly exposed by ambient air, but benzene may also occur in drinking water and foods. Benzene is carcinogenic to humans causing acute non-lymphocytic leukemia. In foods, critical benzene concentrations were detected in the past mainly in alcohol-free beverages, because benzene was formed from benzoic acid. For this reason, the soft-drink industry nowadays abstains from using this preservative, and our results show that benzene is not problematic anymore in this group of beverages (contents below the EU drinking water limit of 1 µg/L). During the monitoring of beverages, however, benzene was detected in carrot juices intended for babies and young children (average 2 µg/L). In this case, a heat-induced formation mechanism is predominant. Model experiments have proven that benzene may be formed by the thermally induced degradation of different precursors contained in carrots (e.g., carotene, phenylalanine, and flavour compounds). This mechanism also leads to benzene contamination in commercial carrot-containing baby menus (complimentary foods) as well as carrots in cans, while freshly pressed carrot juices and home prepared baby foods were found to be benzene-free. Significantly lower benzene concentrations were found in commercial baby menus sold in plastic containers compared to the conventionally used glass jars. Preliminary risk assessments have shown that even for babies the exposure from foods is below thresholds, above which a health risk would be assumed. For reasons of precautionary public health protection and the minimization principle for carcinogenic contaminants, the concentrations in carrot products should be reduced, especially as these products are intended for babies and children, the most sensitive consumer group. The focus should be set on improving the sterilization conditions.     

Production systems – An example from Brazil

Important information about the Brazilian agribusiness, population and economy are presented in this paper, as well as details of beef production, market, industry and production system, to inform people involved in meat industry about details on demography, production, economy and production systems of a country that is the largest player in beef exports in the world and that uses, mostly, Bos indicus based bovine population, reared under pasture conditions, for meat production purposes. Herd size, genetic evaluation programs, quantity of beef produced and market is informed, with figures about the global and major players’ production. Some discussion related to environmental concerns, methane emission and carbon fixation is also presented, as well as meat quality. Meat quality of fed animals is also compared with beef from animals that are raised in pasture conditions.     

Nutrition-sensitive agriculture – a South African perspective

As environmental and social sustainability becomes more urgent, and the resilience of the industrial food system is under threat, addressing nutrition through food systems must go hand in hand with restructuring these systems for greater resilience. South Africa is a middle-income country with a highly dualistic agro-food system, dealing with the burden of undernutrition, diet-related chronic diseases and widespread micronutrient malnutrition. In South Africa, agriculture must maintain national food security while contributing to improving household food security through employment and production for own consumption; and providing access to a more diverse range of safe and quality foods at affordable prices. Agricultural activities can contribute to improved nutrition, if implemented in conjunction with direct nutrition interventions. This study gives an overview of the nutritional status of the South African population, and the history and current operations of the agro-food system. It identifies entry points for nutrition-sensitive agriculture (NSA) to begin to address food and nutrition security challenges. Case studies were identified using grey literature. With few exceptions, these cases were not NSA initiatives per se, yet demonstrated efforts that could inform actions to strengthen the nutrition-sensitivity of the South African food system. NSA is not an all-encompassing solution to food and nutrition insecurity in South Africa, but offers a way of strengthening the nutrition-sensitivity of agricultural initiatives. Viable entry points include linking small scale production and nutrition education; combining low external input farming and nutrition education; strengthening alternative marketing channels and local food economies; monitoring food prices; and developing appropriate governance and institutional arrangements.     

Immunocastration of Male Pigs – Situation Today

Immunological castration of male pigs is an attractive alternative to surgical castration and nowadays is increasingly used in many countries to reduce boar taint and improve pork quality. Moreover, immunocastrated pigs showed reduced sexual and aggressive behaviour compared to entire male pigs, thus improving animal welfare. Carcass and meat quality parameters generally do not differ between immunocastrated and surgically castrated male pigs.     

Fusariotoxins in asparagus – their biosynthesis and migration

Asparagus is often infected by fungi of the Fusarium genus, a causal agent of crown and root rot, which decreases the quantity and quality of spears. Fusarium oxysporum and Fusarium proliferatum are the most severe asparagus pathogens, well known as mycotoxin producers, mainly fumonisins and moniliformin. The present study was undertaken to estimate fumonisin B₁, moniliformin and ergosterol concentrations in asparagus tissue. Moreover, the possibility of toxin transport to the edible asparagus part during the inoculation by F. oxysporum and F. proliferatum of different plant parts (root, crown and stem base) and the potential risk for consumers were assessed. Our studies showed that the highest capability of producing fumonisin B₁ and moniliformin was demonstrated from isolates of F. proliferatum. The highest level of fumonisin B₁ in edible spears was detected when the asparagus crown was inoculated with F. oxysporum and F. proliferatum. The lowest concentration was found in the case of storage root inoculation, which corresponds with mycelium absence and the long distance from the roots to the stem. Similar results were demonstrated for moniliformin. The mycotoxin content was confirmed even in healthy spears (without disease symptoms and mycelium presence), which might indicate that the transport of mycotoxins is possible from the soil through the root system to the top part of the plants.     

Fashion retailing – past,present and future

This issue of Textile Progress reviews the way that fashion retailing has developed as a result of the application of the World Wide Web and information and communications technology (ICT) by fashion-retail companies. The review therefore first considers how fashion retailing has evolved, analysing retail formats, global strategies, emerging and developing economies, and the factors that are threatening and driving growth in the fashion-retail market. The second part of the review considers the emergence of omni-channel retailing, analysing how retail has progressed and developed since the adoption of the Internet and how ICT initiatives such as mobile commerce (m-commerce), digital visualisation online, and in-store and self-service technologies have been proven to support the progression and expansion of fashion retailing. The paper concludes with recommendations on future research opportunities for gaining a better understanding of the impacts of ICT and omni-channel retailing, through which it may be possible to increase and develop knowledge and understanding of the way the sector is developing and provide fresh impetus to an already-innovative and competitive industry.     

Sustainable (food) packaging – an overview

Packaging has an increasingly essential role to play in preserving the value invested in products by ensuring that they can deliver their designed service with minimum wastage. Food contact materials that deliver more units of service with increasingly fewer inputs of energy and materials, and increasingly fewer negative social, economic and environmental impacts, e.g., from emission of wastes, will be more sustainable both in the food processing machines of the industrial system and as packaging for food. Buzz words, whether bio-, nano-, degradable, or whatever comes next, must be critically examined per unit of service delivered to determine if, over the whole life cycle of the products to which they are applied, energy and resource use are minimised, pollution is reduced (not relocated), ecological benefits are created, and social and economic well-being are increased. Only when this caution is applied can a new solution be described as more sustainable.     

Magnetic cotton yarns – optimization of magnetic properties

In this paper, we present the effect of ferrite percentage content and electric current intensity passing through the electromagnet coil on magnetic properties (saturation induction, residual induction, and coercive field) of magnetic staple yarns. Also, we present a method for obtaining magnetic yarns by direct coating with magnetic powder (barium ferrite). The aim of the study is to determine the optimal processing factors that can affect the performance of magnetic characteristics using an experimental design for second-order model. The results show that an increase in ferrite percentage content is influencing the saturation and residual induction more than an increase in applied current intensity. The increase in saturation and residual induction is due to the higher content of ferrite powder from the magnetic solution that adheres on the yarn surface. The higher is the value of coercive field, the larger is the force needed to completely demagnetize the magnetic yarn.     

Ochratoxin A in liquorice products – a review

Liquorice is a herbal medicine produced mainly in China and Iran. This plant is suspected to contain ochratoxin A (OTA), a secondary metabolite produced by fungi. Although liquorice is not included in the daily dietary of humans, the high levels of OTA reported in this product have concerned consumers. Registration of a standard method for measuring the amount of this mycotoxin in liquorice-derived products is an important challenge and requires the introduction of a reliable, simple, fast-performance and reproducible technique. This review examines studies carried out concerning the occurrence of OTA in liquorice products. Recent information regarding contaminated liquorice, the regulatory framework and methods to degrade OTA in liquorice are discussed.     

Conjunctival UV autofluorescence – Prevalence and risk factors

PurposeAutofluorescence of ultraviolet (UV) light has been shown to occur in localised areas of the bulbar conjunctiva, which map to active cellular changes due to UV and environmental exposure. This study examined the presence of conjunctival UV autofluorescence in eye care practitioners (ECPs) across Europe and the Middle East and its associated risk factors.MethodImages were captured of 307 ECPs right eyes in the Czech Republic, Germany, Greece, Kuwait, Netherlands, Sweden, Switzerland, United Arab Emirates and the United Kingdom using a Nikon D100 camera and dual flash units through UV filters. UV autofluorescence was outlined using ImageJ software and the nasal and temporal area quantified. Subjects were required to complete a questionnaire on their demographics and lifestyle including general exposure to UV and refractive correction.ResultsAverage age of the subjects was 38.5 ± 12.2 years (range 19–68) and 39.7% were male. Sixty-two percent of eyes had some conjunctival damage as indicated by UV autofluorescence. The average area of damage was higher (p = 0.005) nasally (2.95 ± 4.52 mm²) than temporally (2.19 ± 4.17 mm²). The area of UV damage was not related to age (r = 0.03, p = 0.674), gender (p = 0.194), self-reported sun exposure lifestyle (p > 0.05), geographical location (p = 0174), sunglasses use (p > 0.05) or UV-blocking contact lens use (p > 0.05), although it was higher in those wearing contact lenses with minimal UV-blocking and no spectacles (p = 0.015). The area of UV damage was also less nasally in those who wore contact lenses and spectacles compared to those with no refractive correction use (p = 0.011 nasal; p = 0.958 temporal).ConclusionUV conjunctival damage is common even in Europe, Kuwait and UAE, and among ECPs. The area of damage appears to be linked with the use of refractive correction, with greater damage nasally than temporally which may be explained by the peripheral light focusing effect.     

Pumpkin seeds – the mycobiota and potential mycotoxins

 75 surface disinfected and 75 non-disinfected Austrian pumpkin seeds were plated directly on to each of the three media, DG-18, DRBC, and MSA 5%, to determine the quantitative as well as qualitative mycobiota. Overall, 902 moulds belonging 25 different species and 17 different genera were isolated. The species were divided as follows: ascomycota, 2; zygomycota, 3; mitosporic fungi, 12. The mycobiota were dominated by Penicillium spp. (263 isolations), Eurotium spp. (139 isolations), and Cladosporium spp. (99 isolations). Rhizopus stolonifer was the predominating fungal species (113 isolations). 15 potential mycotoxigenic mould species contributed to the mycotiota of pumpkin seeds. Received: 31 March 2000 / Revised version: 23 May 2000     

Browning development in bakery products – A review

This paper presents a review regarding several aspects of the development of browning during baking of bakery products, mainly from an engineering point of view. During baking, the formation of colour is due to the Maillard reaction, and caramelization of sugars. Besides the major influence of this phenomenon on the initial acceptance of products by consumers, it is the responsible for other relevant changes occurring in food during baking, i.e. production of flavour and aroma compounds, formation of toxic products (e.g. acrylamide), and decrease of nutritional value of proteins. As well as baking, the development of browning in bakery products is a simultaneous heat and mass transfer process that occurs mostly in a non-ideal system under non-ideal conditions. In addition, the mechanisms of chemical reactions involved are still not elucidated completely, so the process is difficult to control and represents a major challenge for food engineers. Effects of browning on properties of products and experimental, modelling and technological aspects of colour formation during baking are reviewed.     

Die Blauzungenkrankheit – eine neue Tierseuche in Mitteleuropa

Zusammenfassung:  Seit August 2006 breitet sich die Blauzungenkrankheit (engl. Bluetongue, BT) in Mitteleuropa aus, eine ausschlie?lich durch Stechmücken (Gnitzen) übertragene und bis dahin in unseren Breiten nicht vorhandene Tierseuche von Haus- und Wildwiederk?uern. Derzeit sind neben Deutschland bereits etliche weitere mitteleurop?ische L?nder betroffen. Die Infektion mit dem exotischen Bluetonguevirus Serotyp 8 (BTV-8) wird durch heimische Culicoides-Mücken übertragene und ?u?ert sich in klinischen Symptomen, die teilweise auch auf andere bedeutende Seuchen hindeuten k?nnten, so dass eine rasche labordiagnostische Abkl?rung erfolgen muss. Die staatliche Tierseuchenbek?mpfung versucht durch dauernde überwachung, Handelsbeschr?nkungen und neuerdings auch durch Impfung der empf?nglichen landwirtschaftlichen Nutztiere die Blauzungenkrankheit in Mitteleuropa einzud?mmen. Eingegangen: 1. April 2008