• Food Authentication using Infrared Spectroscopic Methods

      Downey, Gerard; Kelly, J. Daniel (Teagasc, 01/06/2006)
      Confirmation of the authenticity of a food or food ingredient is an increasing challenge for food processors and regulatory authorities. This is especially the case when an added-value claim, such as one relating to geographic origin or a particular processing history, is made on the food label. Regulatory agencies are concerned with the prevention of economic fraud while the food processor needs confirmation of such claims in order to protect a brand, the image of which could be severely damaged should an adulterated ingredient make its way into the branded food product.To be of greatest value, any analytical tool deployed to confirm authenticity claims needs to be portable, easy to use, non-destructive and accurate. Infrared spectroscopy, near and mid-infrared, is a tool which has been demonstrated to possess these properties in a wide range of situations.While some applications in food authenticity have been reported, the work undertaken in this project was designed to explore their capabilities regarding a number of products and authenticity issues of particular interest to the Irish agri-food industry i.e. olive oil, honey, soft fruit purées and apple juice.
    • Development of Organic Breads and Confectionery

      Gallagher, Eimear; Keehan, Denise; Butler, Francis; Downey, Gerard (Teagasc, 01/07/2005)
      In recent years, concern for the environment and consumer dissatisfaction with conventional food has led to growing interest in organic farming and food. The demand has also been fuelled by highly-publicised food scares. Food safety and genetic modification issues have led some consumers to opt for organic food as a safer alternative. Recently, there has been a significant increase in the number of launches of organic bakery products in Ireland. As a result, there is an increased need to identify suitable organic bakery ingredients for use in bread and confectionery formulations. However, only a limited number of scientific studies on the physical, chemical and functional properties of organic flours and ingredients exist. The effects of commonly-used ingredients in baking, i.e. organic improvers and fats, on the baking characteristics of organic products have not yet been reported and little is known about the influence of approved additives that may be beneficial to organic baking. Arising from these gaps in the knowledge base on the use of organic flours and ingredients, the objective of this study was to evaluate the chemical, rheological and baking characteristics of white, wholemeal and confectionery organic flours and to assess the baking potential of organic bakery ingredients, in particular improvers, fats and additives. Ingredients and baked goods were compared to non-organic controls.
    • Second Generation GM Foods: Perspectives on Likely Future Acceptance by Irish Consumers

      O'Connor, Elaine; Cowan, Cathal; Williams, Gwilym; O'Connell, John J.; Boland, Maurice; Downey, Gerard (Teagasc, 01/07/2005)
      Two hypothetical second-generation genetically-modified (GM) products, a yogurt and a dairy spread, were evaluated by consumers. Second-generation GM food products offer specific consumer benefits - in the case of this study, health benefits.
    • The market potential for in-conversion organic products in Ireland

      Cowan, Cathal; Connolly, Liam; Howlett, Brendan; Meehan, Hilary; Ryan, Jane; Mahon, Denise; McIntyre, Bridin; Fanning, Martin; Downey, Gerard; European Union; et al. (Teagasc, 01/08/2005)
      This report deals with the market for and financial feasibility of converting from conventional to organic food production in Ireland. All members of the organic supply chain were included in the study i.e. farmers, intermediaries, retailers and consumers, to examine the potential of a market for conversion grade produce. Conversion products are those produced in the second year of the conversion phase from conventional to organic farming. Products do not attain full organic status until this is completed.
    • Nitrofurans: Measuring Tissue-Bound Residues in Meat

      O'Keeffe, Michael; Conneely, Anne; Nugent, Audrey; Downey, Gerard; European Union (Teagasc, 01/08/2006)
      The aims of this project were to (a) develop a range of screening and confirmatory test methods that might be applied to effectively test for the illicit use of the prohibited nitrofuran antimicrobials,(b) study the persistence of nitrofuran antimicrobials as bound metabolite residues inedible tissues and (c) undertake a pan-European survey of the incidence of nitrofurans in retail pork.
    • Adding value to milk by increasing its protein and CLA contents

      Murphy, J.J.; STANTON, CATHERINE; O'Donovan, Michael; Kavanagh, S.; Maher, J.; Patton, Joe; Mohammed, Riaz (Teagasc, 01/08/2008)
      The mid-summer milk protein study was undertaken on 34 commercial dairy farms in 2005 to evaluate the influence of dietary and management variables on milk protein content in mid-season. Data on grass composition, genetic merit of the herds and milk protein content were collected and analysed by multiple regression. Both calving date and genetic merit for milk protein content were significantly associated with milk protein content and were used as adjustment factors when evaluating the association between measures of grass quality and milk protein content. Milk protein content was associated with grass OMD (P = 0.04) and NDF content (P = 0.02) but not with CP content (P = 0.80). It is concluded that herds calving earlier, with a greater genetic merit for milk protein content and consuming better quality pasture would have greater milk protein contents in mid-season.
    • Adding value to cull cow beef

      O'Donovan, Michael; Minchin, William; Buckley, Frank; Kenny, David A.; Shalloo, Laurence (Teagasc, 01/08/2009)
      This project addressed the prospects of increasing the value of cull cow beef and examined the potential of a number of different management and dietary strategies. In Ireland, the national cow herd contributes 350,000 animals to total beef production annually, which represents 22% of all cattle slaughtered (DAF, 2007). A dominant feature of beef production in Ireland is the disposal of cows from the dairy and beef industries, the time of year at which culling occurs influences the number of cows available for slaughter. Suitability of a cow for slaughter is generally not a consideration for dairy or beef farmers.
    • Enzyme Modified Cheese Flavour Ingredients

      Wilkinson, M.G.; Kilcawley, Kieran; Mulholland, E.; Department of Agriculture, Food and the Marine, Ireland (Teagasc, 01/09/2000)
      Enzyme-modified cheeses (EMCs) are defined as concentrated cheese flavours produced enzymatically from cheeses of various ages and are principally used as an ingredient in processed foods, where they provide a cost-effective alternative to natural cheese. They can be used as the sole source of cheese flavour to intensify an existing cheese taste, or to impart a specific cheese character to a more bland product. Their main applications are in processed cheese, analogue cheese, cheese spreads, snack foods, soups, sauces, biscuits, dips and pet foods. Their main advantages over other cheese flavour ingredients are: low production costs, consistency, high flavour intensity, diverse flavour range, extended shelf- life, low storage costs and increased functionality. EMCs are generated utilising the same flavour pathways that occur in natural cheese ripening i.e. proteolysis, lipolysis and glycolysis. They are not as easy to differentiate as natural cheeses, as they are characterised by flavour and aroma alone as texture is not a factor in EMC production. The relationship of the flavour of EMCs to the flavour of the corresponding natural cheese remains unclear. This is especially true for Cheddar EMC which is commercially available in a range of Cheddar flavours . Despite the fact that a wide range of commercial EMCs are available, there is very little detailed information available regarding their properties or the specific production processes used. The main objective of this research was to build a knowledge base on EMC products and to utilise this to develop a biotechnological process for the production of improved enzyme modified cheeses for use as flavour ingredients. The strategy was to establish quantitative relationships between the compositional, proteolytic and lipolytic parameters and the sensory characteristics of EMCs. This data would then be used to develop a predictive model for flavour development in EMC production and the subsequent generation of an optimised EMC process enabling the generation of a range of cheese flavours from single or multiple substrates.
    • Tracking of Salmonella through the Pork Slaughter Process

      Prendergast, Deirdre M.; Duggan, Sharon J.; Duffy, Geraldine; Downey, Gerard; Safefood; National Development Plan 2007-2013 (Teagasc, 01/10/2009)
      To help address the problem of salmonellosis in the Republic of Ireland (RoI), a national Salmonella control programme was introduced in 1997 with a view to reducing the prevalence of Salmonella in pigs on the farm and on pig carcasses. The primary objective of this present study was to determine the correlation between the Salmonella serological and bacteriological status of pigs presented for slaughter and the Salmonella status of pork cuts following slaughter, dressing and chilling. Two additional studies investigated the prevalence and numbers of Salmonella spp. in the boning halls of four commercial pork abattoirs and at retail level in butcher shops and supermarkets in the RoI. The results indicated that categorisation of pig herds on the basis of a historical serological test for Salmonella was not a good predictor of the bacteriological Salmonella status of individual pigs at time of slaughter. However, it is acknowledged that serological testing does help in giving a rough estimate of the overall Salmonella status of a pig herd. There was a linear correlation between prevalence of Salmonella in caecal contents and on pork cuts at factory level; therefore, if the number of herds presented for slaughter with high levels of Salmonella (category 3) was reduced, there would be less potential for contamination of the lairage, equipment etc. and so less likelihood of Salmonella contamination on pork. The impact of crosscontamination during transport, lairage, processing and distribution cannot be ignored and measures to diminish this would significantly reduce the dissemination of Salmonella in the chain and the consequent risk posed. A key finding was the considerable variation in the incidence of Salmonella on different sampling days and in different slaughter plants.
    • Control of Blown Pack Spoilage in Vacuum Packaged Meat

      Bolton, Declan; Moschonas, Galatios; Sheridan, James J.; Downey, Gerard; National Development Plan (Teagasc, 01/10/2009)
      Blown pack spoilage (BPS) represents a significant commercial loss to Irish meat processors. This research discovered that the organisms causing BPS are ubiquitous in the abattoir environment, making eradication very difficult. The risk of BPS is best managed through a process of regular treatment of plant and equipment with a sporicidal agent such as peroxyacetic acid, good hygiene to minimise carcass contamination and removal of the heat shrinkage stage during vacuum packaging as this activates the spores and reduces the time to spoilage.
    • N-3 Polyunsaturated Fatty Acids (PUFAs) Reverse the Impact of Early-Life Stress on the Gut Microbiota

      Pusceddu, Matteo M; El Aidy, Sahar; Crispie, Fiona; O'Sullivan, Orla; Cotter, Paul D.; STANTON, CATHERINE; Kelly, Philip; Cryan, John F.; Dinan, Timothy G.; Department of Agriculture, Food and the Marine; et al. (PLOS, 01/10/2015)
      Background Early life stress is a risk factor for many psychiatric disorders ranging from depression to anxiety. Stress, especially during early life, can induce dysbiosis in the gut microbiota, the key modulators of the bidirectional signalling pathways in the gut-brain axis that underline several neurodevelopmental and psychiatric disorders. Despite their critical role in the development and function of the central nervous system, the effect of n-3 polyunsaturated fatty acids (n-3 PUFAs) on the regulation of gut-microbiota in early-life stress has not been explored. Methods and Results Here, we show that long-term supplementation of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) (80% EPA, 20% DHA) n-3 PUFAs mixture could restore the disturbed gut-microbiota composition of maternally separated (MS) female rats. Sprague-Dawley female rats were subjected to an early-life stress, maternal separation procedure from postnatal days 2 to 12. Non-separated (NS) and MS rats were administered saline, EPA/DHA 0.4 g/kg/day or EPA/DHA 1 g/kg/day, respectively. Analysis of the gut microbiota in adult rats revealed that EPA/DHA changes composition in the MS, and to a lesser extent the NS rats, and was associated with attenuation of the corticosterone response to acute stress. Conclusions In conclusion, EPA/DHA intervention alters the gut microbiota composition of both neurodevelopmentally normal and early-life stressed animals. This study offers insights into the interaction between n-3 PUFAs and gut microbes, which may play an important role in advancing our understanding of disorders of mood and cognitive functioning, such as anxiety and depression.
    • Mesophilic sporeformers identified in whey powder by using shotgun metagenomic sequencing

      McHugh, Aoife; Feehily, Conor; Tobin, John; Fenelon, Mark; Hill, Colin; Cotter, Paul D.; Department of Agriculture, Food and the Marine, Ireland; Science Foundation Ireland; 14/F/883; 11/P1/1137 (American Society for Microbiology, 01/10/2018)
      Spoilage and pathogenic spore-forming bacteria are a major cause of concern for producers of dairy products. Traditional agar-based detection methods employed by the dairy industry have limitations with respect to their sensitivity and specificity. The aim of this study was to identify low-abundance sporeformers in samples of a powdered dairy product, whey powder, produced monthly over 1 year, using novel culture-independent shotgun metagenomics-based approaches. Although mesophilic sporeformers were the main target of this study, in one instance thermophilic sporeformers were also targeted using this culture-independent approach. For comparative purposes, mesophilic and thermophilic sporeformers were also tested for within the same sample using culture-based approaches. Ultimately, the approaches taken highlighted differences in the taxa identified due to treatment and isolation methods. Despite this, low levels of transient, mesophilic, and in some cases potentially pathogenic sporeformers were consistently detected in powder samples. Although the specific sporeformers changed from one month to the next, it was apparent that 3 groups of mesophilic sporeformers, namely, Bacillus cereus, Bacillus licheniformis/Bacillus paralicheniformis, and a third, more heterogeneous group containing Brevibacillus brevis, dominated across the 12 samples. Total thermophilic sporeformer taxonomy was considerably different from mesophilic taxonomy, as well as from the culturable thermophilic taxonomy, in the one sample analyzed by all four approaches. Ultimately, through the application of shotgun metagenomic sequencing to dairy powders, the potential for this technology to facilitate the detection of undesirable bacteria present in these food ingredients is highlighted.
    • Indicator organisms to determine the use of chilling as a critical point in beef slaughter HACCP

      Prendergast, Deirdre M.; Sheridan, James J.; Downey, Gerard (Teagasc, 01/11/2008)
      During chilling, temperatures of carcass surfaces at different sites change over time as do other parameters such as water activity (aw), the structure of the muscle and other tissues, as the carcass enters rigor mortis. Many of these factors are known to have a major effect on cell survival and growth and must be considered in determining the influence of chilling on bacterial survival on carcass surfaces. This study aimed to determine if chilling could be used as a critical control point (CCP) in beef slaughter in relation to pathogens such as E. coli O157:H7 and L. monocytogenes, using E. coli and Listeria innocua as pathogen indicators. The present study was designed to determine the influence of (a) chilling at 10oC for 72 h on the survival of E. coli and (b) chilling at 4oC for 72 h on the survival of L. innocua inoculated at different sites on beef carcasses. Three sites (neck, outside round and brisket) were inoculated (1) immediately after dressing while hot (E. coli and L. innocua) and (2) when cold after chilling (L. innocua). The influence of changes in surface aw was also considered and their relationship to the survival of E. coli and L. innocua over time was assessed. The data are discussed in relation to the use of chilling as a CCP in beef hazard analysis (HACCP) and the monitoring of neck temperature as the most suitable CCP.
    • Adding value to Beef Forequarter Muscles

      Kenny, Tony; Lennon, Ann; Ward, Patrick; Sullivan, Paul; McDonald, Karl; O'Neill, Eileen; Downey, Gerard (Teagasc, 01/11/2008)
      The forequarter constitutes 50% of the weight of a beef carcase but only about 25% of its value.To fulfill the objectives of this project, the work was organised into 4 parts as follows: 1.Characterisation of the available raw material, in terms of properties of individual muscles seamed out from carcasses of representative types of animals produced in Ireland. 2.Comparison of yields and operator time for seaming and conventional boning. 3.Utilisation of separated muscles in added-value products using appropriate tenderising, bonding and forming technology. 4.Transfer of the knowledge and technology to the industry.
    • New Product Development Opportunities for Irish Companies in the British Cheese Market

      Cowan, Cathal; Downey, Gerard (Teagasc, 01/11/2008)
      The primary objective of this research was to identify innovative cheese concepts appropriate for UK consumers and suitable for Irish industry to manufacture. It also aimed to identify personal, situational and market factors that influence consumers when purchasing cheese. This research study used existing market literature, in-depth interviews and consumer focus groups.
    • An examination of the molecular mechanisms controlling the tissue accumulation of conjugated linoleic acid (CLA) in cattle

      Waters, Sinead M.; Hynes, A.C.; Killeen, Aideen P.; Moloney, Aidan P; Kenny, David A. (Teagasc, 01/12/2008)
      Long chain n-3 polyunsaturated fatty acids (n-3 PUFA) and conjugated linoleic acid (CLA) have demonstrable and potential human health benefits in terms of preventing cancer, diabetes, chronic inflammation, obesity and coronary heart disease. Supplementation of cattle diets with a blend of oils rich in n-3 PUFA and linoleic acid have a synergistic effect on the accumulation of ruminal and tissue concentrations of trans vaccenic acid (TVA), the main substrate for ?-9 desaturase which is responsible for de novo tissue synthesis of the cis 9, trans 11 isomer of CLA. This dietary strategy translates into increases in milk concentrations of CLA in dairy cows; however, concentrations in the muscle of beef animals have not always been increased. There is an apparent paradox in that n-3 PUFA supplementation enhances ruminal synthesis of trans-vaccenic acid (TVA), but then inhibits its conversion to CLA possibly through altering the activity of ?-9 desaturase. Recently, the promoter regions of the bovine ?- 9 desaturase gene has been isolated and analysed and has been shown to contain a conserved PUFA response region.
    • Formation of non-native β-lactoglobulin during heat-induced denaturation

      Kehoe, Joseph James; Wang, Lizhe; Morris, Edwin R; Brodkorb, Andre; Teagasc Walsh Fellowship Programme; Department of Agriculture, Food and the Marine (Springer, 01/12/2011)
      A mechanism describing the denaturation and aggregation behavior during heat-treatment of pure β-lactoglobulin and β-lactoglobulin in whey protein isolate (WPI) under selected conditions (20 to 90 gL−1 in water at pH 7.0, 78 °C) is presented. A combination of reversed-phase and gel permeation chromatography was used to study the disappearance of native β-lactoglobulin and the formation of non-native intermediates in the aggregation process. The mean reaction order for pure β-lactoglobulin and β-lactoglobulin in WPI were the same, 1.4. While the rate of β-lactoglobulin denaturation was greater in WPI there was less aggregation compared to that of pure β-lactoglobulin. More of the β-lactoglobulin in WPI remained in a non-native monomer intermediate state after 30 min of heating. After an initial lag period, during which non-native monomers appeared, aggregates formed and rapidly reached a plateau in terms of their size. These aggregates were visualized using atomic force microscopy. There was no significant effect of protein concentration on either aggregate size or the number of exposed sulfhydryls in the heated solutions.
    • Generation of Bioactive Hydrolysates and Peptides from Bovine Hemoglobin with In Vitro Renin, Angiotensin-I-Converting Enzyme and Dipeptidyl Peptidase-IV Inhibitory Activities

      Lafarga, Tomas; Rai, Dilip K.; O'Connor, Paula M.; Hayes, Maria; Teagasc Walsh Fellowship Programme; Department of Agriculture, Food and the Marine; 11/F/043 (Wiley, 02/03/2016)
      Bovine hemoglobin was selected for use in the generation of bioactive hydrolysates with potential for use as functional food ingredients for prevention of disorders such as hypertension, obesity and diabetes. Bovine hemoglobin was isolated and hydrolyzed with papain, which was selected using in silico analysis. The generated hydrolysate was enriched by ultrafiltration and further purified by high performance liquid chromatography. A number of peptides were identified using de novo peptide sequencing and these peptides were chemically synthesized to confirm their bioactivity in vitro. Three multifunctional peptides with both, ACE-I and renin-inhibitory properties and one peptide with ACE-I-inhibiting properties were identified. These included the di-peptide HR with ACE-I and renin IC50 values of 0.19 and 7.09 mM, respectively. The generated papain hydrolysate of bovine hemoglobin not only inhibited the enzymes ACE-I and renin but also the enzyme DPP-IV, which has been linked to type-2 diabetes.
    • Relatedness between the two-component lantibiotics lacticin 3147 and staphylococcin C55 based on structure, genetics and biological activity

      O'Connor, Eileen B; Cotter, Paul D.; O'Connor, Paula M.; O'Sullivan, Orla; Tagg, John R; Ross, R Paul; Hill, Colin (Biomed Central, 02/04/2007)
      Background: Two component lantibiotics, such as the plasmid-encoded lacticin 3147 produced by Lactococcus lactis DPC3147 and staphylococcin C55 produced by Staphylococcus aureus C55, represent an emerging subgroup of bacteriocins. These two bacteriocins are particularly closely related, exhibiting 86% (LtnA1 and C55α) and 55% (LtnA2 and C55β) identity in their component peptides. The aim of this study was to investigate, for the first time for any two component bacteriocins, the significance of the relatedness between these two systems. Results: So close is this relatedness that the hybrid peptide pairs LtnA1:C55β and C55α:LtnA2 were found to have activities in the single nanomolar range, comparing well with the native pairings. To determine whether this flexibility extended to the associated post-translational modification/processing machinery, the staphylococcin C55 structural genes were directly substituted for their lacticin 3147 counterparts in the ltn operon on the large conjugative lactococcal plasmid pMRC01. It was established that the lacticin LtnA1 post-translational and processing machinery could produce functionally active C55α, but not C55β. In order to investigate in closer detail the significance of the differences between LtnA1 and C55α, three residues in LtnA1 were replaced with the equivalent residues in C55α. Surprisingly, one such mutant LtnA1-Leu21Ala was not produced. This may be significant given the positioning of this residue in a putative lipid II binding loop. Conclusion: It is apparent, despite sharing striking similarities in terms of structure and activity, that these two complex bacteriocins display some highly dedicated features particular to either system.
    • The efficacy of thuricin CD, tigecycline, vancomycin, teicoplanin, rifampicin and nitazoxanide, independently and in paired combinations against Clostridium difficile biofilms and planktonic cells

      Mathur, Harsh; Rea, Mary; Cotter, Paul D.; Hill, Colin; Ross, R Paul; Science Foundation Ireland; SFI/12/RC/2273 (Biomed Central, 02/06/2016)
      Background Thuricin CD is a two-component antimicrobial, belonging to the recently designated sactibiotic subclass of bacteriocins. The aim of this study was to investigate the effects of thuricin CD, as well as the antibiotics, tigecycline, vancomycin, teicoplanin, rifampicin and nitazoxanide when used independently and when combined at low concentrations on the viability of Clostridium difficile 20291 R027, TL178 R002, Liv022 R106, DPC6350 and VPI10463 biofilms and planktonic cells. Results On the basis of XTT (2,3-bis[2-methyloxy-4-nitro-5-sulphophenyl]-2H-tetrazolium-5-carboxanilide)-menadione biofilm viability assays, we found that thuricin CD was effective against biofilms of R027, Liv022 R106 and DPC6350 when used independently while nitazoxanide and rifampicin were also potent against biofilms of R027 and DPC6350, when applied on their own. Tigecycline was found to be effective against R027 and DPC6350 biofilms, whereas teicoplanin and vancomycin when used independently were only effective against DPC6350 biofilms. The efficacies of the antibiotics rifampicin, tigecycline, vancomycin and teicoplanin against C. difficile 20291 R027 biofilms were significantly potentiated when combined with thuricin CD, indicating effective antimicrobial combinations with this sactibiotic against R027 biofilms. However, the potency of nitazoxanide against R027 biofilms was significantly diminished when combined with thuricin CD, indicating an ineffective combination with this sactibiotic against R027 biofilms. Paired combinations of thuricin CD along with these five antibiotics were effective at diminishing the viability of DPC6350 biofilms. However, such combinations were largely ineffective against biofilms of TL178 R002, Liv022 R106 and VPI10463. Conclusions To the best of our knowledge, this is the first study to highlight the activity of a sactibiotic bacteriocin against biofilms and the first to reveal the potency of the antibiotics tigecycline, teicoplanin and nitazoxanide against C. difficile biofilms. On the basis of this study, it is apparent that different strains of C. difficile possess varying abilities to form biofilms and that the sensitivities of these biofilms to different antimicrobials and antimicrobial combinations are strain-dependent. Since the formation of relatively strong biofilms by certain C. difficile strains may contribute to increased cases of antibiotic resistance and recurrence and relapse of C. difficile infection, the findings presented in this study could provide alternative strategies to target this pathogen.