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This study offers insight into the dynamics of bacterial populations in fresh cuts of suckling lamb under four different atmospheric conditions: air (A), and three Modified Atmosphere Packaging (MAP) environments, 15%O2/30%CO2/55%N2 (C, commercial), 70%O2/30%CO2 (O), and 15%O2/85%CO2 (H) for 18 days. Microbial analyses by both conventional methods and PCR-DGGE were performed. Controversial and surprising results emerged from comparing both methods in relation to the genus Pseudomonas. Thus, conventional methods detected the presence of high numbers of Pseudomonas colonies, although PCR-DGGE only detected this genus in air-packaged samples. PCR-DGGE detected higher microbial diversity in the control samples (A) than in the modified atmospheres (C, O, H), having atmosphere H the fewest number of species. Brochothrix thermosphacta, LAB (Carnobacterium divergens and Lactobacillus sakei), and Escherichia spp. were detected in all the atmospheres throughout storage. Moreover, previously undescribed bacteria from lamb meat such as Enterobacter hormaechei, Staphylococcus equorum and Jeotgalicoccus spp. were also isolated in this study by DGGE. Additionally, qPCR analysis was used to detect and characterize strains of Escherichia coli. Virulence genes (stx1, stx2 and eae) were detected throughout storage in 97% of the samples. A high CO2 atmosphere was the most effective packaging combination doubling storage time in comparison with commercial atmosphere.

This study describes a performance measurement of implemented food safety management system (FSMS) along the lamb chain using an FSMS-diagnostic instrument (FSMS-DI) and a Microbiological Assessment Scheme (MAS). Three slaughterhouses, 1 processing plant and 5 butcher shops were evaluated. All the actors along the lamb chain achieved a moderate risky contextual situation, operating in a basic-average FSMS, which was not enough to obtain a good food safety output. Different suggestions are advised for each actor along the lamb chain for improvements towards higher FSMS activity levels or lower risk levels in context characteristics. The combined assessment is a useful tool to identify the possible causes of poor food safety performance in the lamb chain using few sampling locations, saving time and money.

Western-European consumers have become not only more demanding on product availability in retail outlets but also on other food attributes such as quality, integrity, and safety. When (re)designing food supply-chain networks, from a logistics point of view, one has to consider these demands next to traditional efficiency and responsiveness requirements. The concept ‘quality controlled logistics’ (QCL) hypothesizes that if product quality in each step of the supply chain can be predicted in advance, goods flows can be controlled in a pro-active manner and better chain designs can be established resulting in higher product availability, constant quality, and less product losses. The paper discusses opportunities of using real-time product quality information for improvement of the design and management of ‘AgriFood Supply Chain Networks’, and presents a preliminary diagnostic instrument for assessment of ‘critical quality’ and ‘logistics control’ points in the supply chain network. Results of a tomato-chain case illustrate the added value of the QCL concept for identifying improvement opportunities in the supply chain as to increase both product availability and quality. Future research aims for the further development of the diagnostic instrument and the quantification of costs and benefits of QCL scenarios.

Binnen het Europees project PathogenCombat is het diagnose instrument ontwikkeld. Hiermee krijgt de voedingsmiddelenproducent een indruk van het risiconiveau van de context waarin zijn voedselveiligheidssysteem opereert. Daarnaast geeft het inzicht in het prestatieniveau van zowel het systeem zelf als van de microbiële output van het systeem.

Interdisciplinary thinking as a skill appears to be of value to higher education students and those in employment. This idea is explored with reference to the agricultural and life sciences. The need for further understanding of the development of interdisciplinary thinking is acknowledged. This is closely related to the requirement for well-founded curriculum and course design. This publication presents a brief introduction to a systematic review of scientific research into teaching and learning in interdisciplinary higher education. While tentative, the understanding arising from the review findings is considered to be of potential value to educational practice. A selection of the review findings is presented by way of illustration. The selection is believed to be of relevance to the agricultural and life sciences. The review findings presented here take the form of interdisciplinary thinking sub skills and enabling conditions.

Changes in food supply chains, health and demographic situations, lifestyle and social situations, environmental conditions, and increased legislative requirements have led to significant efforts in the development of quality and safety management systems in agribusiness and food industry worldwide (Ropkins and Beck, 2000; Efstratiadis, Karirti, and Arvanitoyannis, 2000; Jacxsens, et al, 2009a, Luning and Marcelis, 2009a). Nowadays, companies have implemented various quality assurance (QA) guidelines and standards, such as GMP and HACCP guidelines (like General Principles of food hygiene (Codex Alimentarius 2003), GFSI guidance document (GFSI (2007), and quality assurance standards (like ISO 9001:2008 (2008), ISO22000:2005 (2005), BRC (2008), and IFS (2007) into their company own food safety management system. The performance of such systems in practice is, however, still variable. Moreover, the continuous pressure on food safety management system (FSMS) performance and the dynamic environment wherein the systems operate (such as emerging pathogens, changing consumer demands, developments in preservation techniques) require that they can be systematically analysed to determine opportunities for improvement (Wallace, et al, 2005; Manning et al, 2006; Van der Spiegel et al, 2006; Cornier et al, 2007; Luning et al, 2009a). Within the European project entitled ‘PathogenCombat- EU FOOD-CT-2005-007081’ various tools have been developed to support food companies and establishments in systematically analysing and judging their food safety management system and its microbiological performance as basis for strategic choices on interventions to improve the FSMS performance. This chapter describes briefly principles of the major tools that have been developed and some others, which are still under still under construction.

Binnen het Europees project PathogenCombat zijn nieuwe tools ontwikkeld waarmee de prestaties van een voedselveiligheidssysteem kunnen worden gemeten. Vandaag deel 1 over het Microbial Assessment Scheme (MAS), een protocol voor een microbiologisch monternameplan.

Increasing public demand for adequate and safe food supply has led to extensive development in the field of plant-animal production, food processing, quality and safety procedures, food analysis and control and regulations. However, safety of food can only be guaranteed by the integration of control systems in the complete food chain ¿from stable to table¿. This book covers the total agri-food chain. The first section includes a chapter giving a clear overview of the food production chain, followed by chapters about distinct safety risk factors (biological, chemical, physical and others) occurring in the agri-food chain. The third section deals with various systems to handle these risk factors. It includes a chapter on the various Quality assurance systems, a detailed chapter on HACCP, as well as on risk management, modelling of safety, and tracking and tracing. The last section includes chapters on the different stakeholders (consumer, legislation, ethics) that are concerned with food safety. The book is aimed at supporting educational programmes on safety in agri-food chains in higher education and at the academic level. It can also be used as a handbook in food industry and agri-business.

In het onderzoeksprogramma Profetas (Protein Foods, Environment, Technology and Society) worden de mogelijkheden onderzocht voor een overgang van dierlijke naar plantaardige eiwitten in de voeding

The book focuses on consumer-driven Quality Management in food production systems using a product-based approach. It integrates organizational and technological aspects of food product quality into one techno-managerial concept and it presents an integrated view of how Quality Management is to be situated in a chain-oriented approach. Topics covered include: consumer perception of product quality organization and quality management the use of tools and methods in quality design control, improvement and assurance from both a technological and management perspective.

Fruits of Capsicum annuum and C. frutescens are commonly used in the diet because of their typical colour, pungency, taste. and distinct aroma. The fruits are eaten fresh or processed, as unripe (green) or ripe (e.g., red, yellow, orange, white) peppers. In the last decade. attention is shifting towards flavour as an important quality parameter for fruits and vegetables. The flavour of fruits and vegetables, as perceived during consumption, is the overall sensation provided by the interaction of taste, odour, mouth feel, sight, and sound. The composition of non-volatile compounds influences mainly the sensory perceived taste, while the aroma is affected by volatile compounds.In this thesis, the flavour, including taste, aroma, non-volatile and volatile compounds, of fresh and dried bell peppers were evaluated. The major Dutch bell pepper cultivar for export, i.e., C. annuum cv. Mazurka, was used as basic cultivar throughout the thesis, others were included for comparison of results.Instrumental and sensory flavour evaluation of fresh bell peppersDevelopment of non-volatile bell pepper compounds . In chapter 2, some growth characteristics and changes in compositions of non-volatile compounds (sugars, organic acids) during ripening of cv. Mazurka and cv. Evident were investigated. The development of the fruits showed a growth (between 4-7 weeks after fruit set) and ripening phase (7-10 weeks). During growth, fresh weight increased rapidly, while during ripening the colour turned from green to red, which was reflected in a decreased level of chlorophyll a (i.e., green pigments) and an increased level of carotenoids (i.e., orange/red pigments). Two high performance liquid chromatography (HPLC) methods were developed for the analysis of sugars and organic acids in bell peppers. The sugars detected were, sucrose, glucose, and fructose, and the major organic acids detected were ascorbic, citric and malic acid, while oxalic, fumaric, shikimic, and pyroglutamic: acid were present at lower concentrations. The levels of sugars and organic acids showed distinct ripening related patterns, i.e., glucose, fructose, citric and ascorbic acid increased while sucrose and malic acid decreased.Relationships between non-volatile compounds and taste . Based on these time series, three distinct ripening stages (i.e., green, turning, and red) of cv. Mazurka and cv. Evident were selected for instrumental and sensory evaluation, in Chapter 3. The composition of sugars and organic acids were analysed and the fruits were evaluated by a sensory descriptive panel on flavour attributes, perceived while eating. The flavour of green bell peppers was characterised by bitter taste and grassy, green bell pepper, and cucumber aroma, while red bell pepper aroma, sweet and sour taste were typical for the turning and red fruits. The relationships between sugars and sweetness, and organic acids and sourness, and dissociated organic acids and sourness were examined using principal component analysis (PCA). It appeared that sweetness, which was typical for the ripe stages, closely related to glucose, fructose, total sugar, and dry matter content, while sourness, also characteristic for the ripe stages, closely related to total citric and total ascorbic acid. PCA on calculated undissociated and dissociated acids revealed that, mainly undissociated ascorbic acid and citric acid in the "-1" and "-2" dissociation forms related closely with sourness. Based on these results and the available literature, it was suggested that undissociated ascorbic acid might be directly important for the sour perception, while the dissociated forms of citric acid influenced the sourness by increasing the proton (H +) concentration.Development of volatile bell pepper compounds . In chapter 4, the same ripening stages of cv. Mazurka were selected for evaluation of the volatile compounds, for which samples were cut into pieces or completely homogenised. Sixty four compounds were analysed and identified in the headspaces of the different samples by gas chromatography (GC) and GC-mass spectrometry. A trained sniffing port panel detected and characterised 30 odour compounds, of which 21 could be identified. The GC-sniffing profiles of all ripening stages and sample preparations had several odour compounds in common, i.e., 2,3-butanedione (caramel odour), 1-penten-3-one (chemical/pungent, spicy), hexanal (grassy), 3-carene (red bell pepper, rubbery), (Z)-β-ocimene (rancid, sweaty), octanal (fruity), and 2-isobutyl-3-methoxypyrazine (green bell pepper). Furthermore, major ripening and preparation related differences were observed. During ripening from green to red, many volatile compounds having green-related odour notes e.g., (Z)-3-hexenol (grassy, lettuce, cucumber), nonanal (mushroom, herbal), 2-sec-butyl-3-methoxypyrazine (carrot, lettuce, grassy), linalool (floral, green bell pepper), (2)-3-hexenal (grassy, green bell pepper, fruity), and 1-hexanol (fruity, green bell pepper, herbal), decreased or even disappeared. Only the levels of (E)-2-hexenal and (E)-2-hexenol, which have almond, fruity, sweet odours, were higher in the turning and red fruits. Disruption of the cell structure by homogenization of the fruits favoured oxidation of unsaturated fatty acids by lipoxygenase and other enzymes, and stimulated the formation of related alcohols, aldehydes, and ketones; several of these compounds had distinct odour notes.Biochemical aspects of the formation of specific volatile bell pepper compounds . The development and origin of these enzymatic formed volatiles were studied in more detail in Chapter 5. Extracts of green bell peppers of cv. Mazurka were analysed for the presence of lipoxygenase (LOX); a pH-optimum of 5.5-6.0 was obtained and enzyme activity was 100% and 51% inhibited by two specific LOX inhibitors (10 mM of n -propyl gallate and 340μM of 5,8,11,14-eicosatetraynoic acid). During bell pepper ripening, LOX activity decreased 70% between 6 and 8 weeks after fruit set. The composition of enzymatic formed volatiles showed four typical ripening related patterns. The origin of these compounds was investigated by adding specific LOX substrates to homogenates of green and red bell peppers. Addition of linoleic acid to green homogenates increased significantly the levels of hexanal, hexanol, 2-pentylfuran, (E)-2-heptenal, (E)-2-octenal, (E)-2-nonenal, but also (2)-3-hexenal, whereas addition of linolenic acid to the same homogenates increased the levels of (2)-3-hexenal, (E)-2-hexenal, (Z)-2-hexenal, (Z)-2- pentenal, (E)-2-pentenal, (Z)-2-pentenol, (E)-2-pentenol, and 1-penten-3-one; similar qualitative effects were observed in the red pepper homogenates. A biochemical pathway was proposed for the formation of volatile bell pepper compounds upon tissue disruption based on experimental data and comprehensive literature.Influence of hot-air drying on the instrumental and sensory flavour evaluation of fresh bell peppersEffects of hot-air drying on the composition of non-volatile and volatile flavour compounds. In chapter 6, the composition of non-volatile and volatile odour compounds were analysed before and after drying of four bell peppers with distinct flavours, i.e., green and red cv. Mazurka, white cv. Blondy, and yellow cv. Kelvin. Hot-air drying affected both the composition of non-volatile and volatile compounds. The levels of glucose, fructose, ascorbic, citric, and oxalic acid decreased, while the levels of sucrose, malic, fumaric, and cis-aconitic acid increased. Glucose, fructose, and ascorbic acid possibly participated in the Maillard reaction during heating. The effects of hot-air drying on the composition of volatile bell pepper compounds could be distinguished in three groups i.e., 1) compounds which decreased or disappeared, 2) compounds which increased or were formed, and 3) compounds which showed no clear changes.The first group represented the majority of volatiles, which apparently evaporated during drying. Most of these compounds were partly retained in the dried bell peppers, but some disappeared completely such as, (Z)-2-pentenal, (E)-2-pentenal, (2)-3-hexenal, (Z)- 2-pentenol, (E)-2-pentenol, (E,E)-2,4-hexadienal, and (E,Z)-2,4-hexadienal. The majority of these compounds were ascribed to the enzymatic breakdown of unsaturated fatty acids upon tissue disruption (Chapter 5). Therefore, it was suggested that the disappearance of these compounds was due to heat inactivation of enzymes more than evaporation during drying. Sniffing port evaluation showed that the compounds, which decreased or disappeared after drying, had mainly "fresh" odour notes like lettuce/grassy/green bell pepper ((Z)-3-hexenal), fruity/almond ((E)-2-hexenal), fruity (octanal), lettuce/green bell pepper ((Z)-3-hexenol), and grassy/green bell pepper (Z)-2-hexenal,The second group included compounds which increased or were formed during drying. The increased levels of 4-octen-3-one, (E)-2-heptenal, (E)-2-octenal, (E,Z) and (E,E)-2,4-heptadienal, decanal, and (E)-2-nonenal were possibly due to autoxidation of unsaturated fatty acids. Whereas, the increased levels of 2- methylpropionic and 2- and 3-methylbutyric acid, 2-methylpropanal, and 2- and 3- methylbutanal seemed to be due to Strecker degradation. Sniffing port evaluation showed that the latter three compounds had distinct cacao, sweaty, and spicy odour characteristics.Changes of the aroma profile of fresh bell peppers due to hot-air drying. In chapter 7, the effects of hot-air drying on the fresh aromas of the four different bell peppers were investigated in more detail. The percentage composition of odour active compounds in the fresh and dried samples were analysed, and the fruits were evaluated by a sensory descriptive panel on aroma attributes, as perceived while smelling. On one hand, hot-air drying decreased the intensity scores of several characteristic fresh aroma attributes. For example, in the green and white fruits, mainly "green" attributes like herbal, grassy, green bell pepper, and cucumber decreased after drying. Moreover, the intensity of the aroma attributes fruity/fresh and floral decreased in the green, white, and red but not in the yellow samples. GC-analysis of the odour active compounds showed that the percentage peak areas of (2)-3-hexenal, 2-heptanone, (Z)-2-hexenal, (E)-2-hexenal, hexanol, (Z)-3-hexanol, (E)-2-hexenol, and linalool, which possessed green, vegetable-like, fruity, and floral characteristics, decreased during drying, which may be responsible for the decreased intensity scores of corresponding aroma attributes in the dried samples. On the other hand, hot-air changed the aroma profile. Five extra attributes, i.e., cacao, caramel, nutty, savoury, and dried tomato, were necessary to describe the aroma of the bell pepper samples after drying. The major odour active compounds detected in the dried samples were 2-methylpropanal, 2 and 3-methylbutanal hexanal, and nonanal. Also, the levels of 2,3-butanedione, 2,3-pentanedione, 4-octene-3-one, (E)-2-octenal, and (E)-2-nonenal were significantly higher in the dried bell peppers. Several of these compounds having cacao, spicy, sweaty/rancid, and sweet odour characteristics may contribute to aroma attributes like savoury, sweettsickly, rancid/sweaty, cacao, and caramel, which were characteristic for all dried samples.Modelling the lipid oxidation, Strecker degradation, and Maillard reaction products during hot-air drying of bell peppers . In Chapter 8, the complex behaviour of volatile bell pepper compounds during drying at different time and temperature conditions was described by four distinct kinetic mechanisms.This thesis provided basic knowledge about the flavour of fresh and hot-air dried bell peppers. This knowledge can be used to study effects of, for example, harvest time, growth conditions, sample variation, cultivars, and seasons on the flavour of fresh and/or dried bell peppers. Furthermore, in this thesis a biochemical pathway was proposed for the enzymatic development of bell pepper volatiles, which can be used as basis for detailed studies on the enzymatic formation of bell pepper volatiles. Finally, the complex behaviour of volatile compounds during hot-air drying of bell peppers was described by four different kinetic mechanisms. This kinetic approach may be used to investigate the behaviour of volatiles in other dynamic processes.