• Dairy Ingredients for Chocolate and Confectionery Products.

      Keogh, M.K.; Twomey, Myra; O'Kennedy, Brendan; Auty, Mark; Kennedy, R.; O'Keeffe, James; Kelleher, Colin T (Teagasc, 2001-05-01)
      High free-fat, spray-dried powders were successfully produced at a lower fat content (40% rather than 56%) using ultrafiltration. Chocolates made from these powders had improved flow properties and superior quality. The stability, viscosity and firmness of toffees were improved by optimising the casein, whey protein and lactose levels of skim milk powders used in their manufacture.
    • Dairy Ingredients for the Baking Industry.

      Keogh, M.K.; Neville, Denis P.; Stanton, Catherine; Auty, Mark; Kennedy, R.; Arendt, Elke (Teagasc, 2001-08-01)
      Shortenings (baking fats), microencapsulated using dairy ingredients and milk protein hydrolysates, were produced for testing in a variety of baked products. The powders were evaluated for their functionality as powdered baking fats, as potential replacers of synthetic emulsifiers, as ingredients capable of improving baking performance or as potential health-enhancing ingredients. These studies provide the technology for the dairy industry to enter the specialised food ingredients sector with a siftable, non-greasy, free-flowing powdered fat for the baking industry.
    • Dairy Ingredients in Chocolate

      Keogh, M.K.; O'Kennedy, Brendan; Twomey, Myra; O'Brien, Nora M.; Kennedy, B.; Gorry, C. (Teagasc, 1998-09-01)
      The main objective was to assess and control the contribution of various ingredient components to chocolate behaviour and to optimise ingredients for specific chocolate applications. A key aim, therefore, was to understand the role of composition and particle structure and to produce spray dried powders with a functionality in chocolate as close as possible to roller dried powders. By demonstrating how the powder properties affect chocolate, it should be possible to control the functional properties of the powders to meet any powder or chocolate specification. Novel powder compositions indicated by this work should also be useful to chocolate makers. The ability to make chocolate under test conditions and to assess the role of milk powders or other ingredients has been put in place for the first time in Ireland. Previous knowledge of milk seasonality and of powder technology has provided a basis for understanding variations in milk powder functionality in chocolate. Spray dried powders with mean free fat values of 50 to 94%, particle sizes of 30 to 65 mm and vacuole volumes of 0.0 to 3.9 ml/100g were produced from milks of varying composition but under the same processing conditions. Advances were made in analysing powder structure through microscopy, particle size and occluded air measurement. Valuable new information has been generated on the changes in free fat, solid fat content, particle size and occluded air in powders. Explanations were provided for the first time for the complex effects of these properties on chocolate viscosity and yield value. This information will also make a positive contribution to other projects in the milk powder area. Good contacts have been established with multinational manufacturers and with producers of milk powder for chocolate.
    • Developing sous vide/freezing systems for ready-meal components

      Tansey, Fergal; Gormley, Ronan T.; Carbonell, Serge; Oliveira, Jorge; Bourke, Paula; O'Beirne, David; Department of Agriculture, Food and the Marine (Teagasc, 2005-04)
      Sous vide cooking involves sealing raw or par-cooked food in a vacuumised laminated plastic pouch or container, cooking by controlled heating, rapid chilling and then re-heating for consumption. The chilled storage period is up to 21 days at 0 to 3oC. The recommended thermal process for sous vide products is 90oC for 10min or its time-temperature equivalent. Concerns about the safety of sous vide products, mainly due to the potential for temperature abuse in the chill chain, has prevented the widespread use of this technology. The role of the current project, therefore, was to investigate sous vide cooking followed by freezing, as a safe alternative to sous vide/chilling for 10 ready-meal components i.e. carbohydrates (potatoes, pasta, rice), vegetables (carrots, broccoli) and muscle foods (salmon, cod, chicken, beef and lamb).
    • Developing Sous Vide/Freezing Systems for Ready-Meal omponents

      Tansey, Fergal; Gormley, Ronan T.; Carbonell, Serge; Oliveira, Jorge; Bourke, Paula; O'Beirne, David (Teagasc, 01/04/2005)
      Sous vide cooking involves sealing raw or par-cooked food in a vacuumised laminated plastic pouch or container, cooking by controlled heating, rapid chilling and then re-heating for consumption. The chilled storage period is up to 21 days at 0 to 3oC. The recommended thermal process for sous vide products is 90oC for 10min or its time-temperature equivalent. Concerns about the safety of sous vide products, mainly due to the potential for temperature abuse in the chill chain, has prevented the widespread use of this technology. The role of the current project, therefore, was to investigate sous vide cooking followed by freezing, as a safe alternative to sous vide/chilling for 10 ready-meal components i.e. carbohydrates (potatoes, pasta, rice), vegetables (carrots, broccoli) and muscle foods (salmon, cod, chicken, beef and lamb).
    • Development and Application of Strategies to Generate Bacteriophage Resistant Strains for Use in Milk Fermentation Processes

      Ross, R Paul; Fitzgerald, Gerald F; Coffey, Aidan; Coakley, M.; O'Sullivan, Daniel (Teagasc, 1999-02-01)
      The objectives of this project were firstly, the identification of natural phage resistance systems for exploitation, secondly, the development of methodologies to utilise these systems to improve the bacteriophage resistance of starter strains for use in milk fermentation processes, and thirdly, the actual application of these methodologies to improving starter strains. The main conclusions were as follows: Three new natural plasmid (DNA)-associated bacteriophage resistance systems were identified at Moorepark. The detailed genetic makeup of the phage resistance plasmid (pMRC01) was elucidated. Bacteriophages currently evolving in the industrial cheese-making environment were monitored to facilitate the judicious choice of phage resistance systems for use in commercial starter cultures which can more effectively target the documented problematic phage types. Two highly virulent phages targeting important cheese starters were identified in the industrial cheese-making environment. A reliable food-grade method to facilitate the transfer of phage resistance systems to cheese-making starter strains was developed. This is based on bacteriocin immunity-linked phage resistance. Phage resistant cheese starter cultures were developed through natural selection and by molecular manipulation using phage resistance plasmids. The phage resistance plasmid pMRC01 was introduced to 31 cheese starter strains.
    • Development and Evaluation of Caseins/Caseinates for use as Ingredients in Food Products

      Mehra, Raj; Walsh, Daniel; O'Kennedy, Brendan; Kelly, Philip M. (Teagasc, 1998-09-01)
      The overall objective of this project was to investigate the effects of key processing steps in the industrial production of acid casein on the characteristics and functionality of sodium caseinate with particular emphasis on analytical/functionality testing and seasonal/lactational effects on the original milk. The main conclusions were as follows: The most significant result indicates that drying and concentration after washing of the acid casein curd are responsible for alterations in the structure of casein, which result in sodium caseinates with different properties. This was confirmed in the case of two acid casein plants investigated which showed similar results even though using different washing and drying technologies. This difference due to the drying step may be further amplified depending upon whether commercial sodium caseinate is manufactured from acid casein in the dried or wet curd state. The analytical and functional testing methodology adapted in our laboratory proved effective in predicting the effects of processing steps on the functionality of sodium caseinate. In particular, the ability to detect the presence of aggregate formation was particularly important. The database generated subsequently helped an acid casein manufacturer in modifying its process(es) to manufacture experimental sodium caseinate for specific food end-uses. Progress was greatly facilitated by the collaboration of individual manufacturers in the sourcing of problem samples from previously manufactured codes, and facilitating access to process plant during production. In a commercial application of the database, confidential work was undertaken on behalf of a client. Experimentally-produced sodium caseinate ingredients were evaluated using our adapted functionality testing methods and based on the results, the company was able to modify its process(es) to produce sodium caseinates with functionality for specific food end-users. It was concluded that while processing parameters in the production of acid casein can have a significant effect on the functional behaviour of the resultant sodium caseinate, the ability to assess this change in functional behaviour, through relevant functional testing, was equally important.
    • The development and/or validation of novel intervention technologies to assure meat food safety

      Bolton, Declan J.; Byrne, Brian; Lyng, James G. (Teagasc, 2007-02)
      This project was undertaken to fill some of the knowledge gaps in meat food safety from farm to fork. The data provide the scientific basis for a clean sheep policy to reduce the impact of fleece as a source of microbial contamination on ovine carcasses at the beginning of the slaughter process. At the other end of the slaughter-line, a polyurethane sponge swabbing technology was developed for ovine and bovine carcass sampling as required in 2001/471/EC and the new European Commission Hygiene Regulations. At the processing stages, studies were undertaken to determine the most effective media for the recovery and culture of Cl. perfringens cells and spores; the results were then applied to thermal inactivation studies on these bacteria. Thermal resistance data were also obtained for Bacillus cereus and a radio frequency cook for meat products was validated in terms of the destruction of Cl. perfringens and B. cereus cells and spores. Finally, an aerobiology study investigated the effectiveness of a range on measures to prevent air acting as a vector for bacterial dispersion in a meat processing plant.
    • The Development and/or Validation of Novel Intervention Technologies to Assure Meat Food Safety

      Bolton, Declan J.; Byrne, Brian; Lyng, James G.; Downey, Gerard; Department of Agriculture, Food and the Marine, Ireland; Food Safety Authority of Ireland (Teagasc, 01/02/2007)
      This project was undertaken to fill some of the knowledge gaps in meat food safety from farm to fork. The data provide the scientific basis for a clean sheep policy to reduce the impact of fleece as a source of microbial contamination on ovine carcasses at the beginning of the slaughter process. At the other end of the slaughter-line, a polyurethane sponge swabbing technology was developed for ovine and bovine carcass sampling as required in 2001/471/EC and the new European Commission Hygiene Regulations. At the processing stages, studies were undertaken to determine the most effective media for the recovery and culture of Cl. perfringens cells and spores; the results were then applied to thermal inactivation studies on these bacteria. Thermal resistance data were also obtained for Bacillus cereus and a radio frequency cook for meat products was validated in terms of the destruction of Cl. perfringens and B. cereus cells and spores. Finally, an aerobiology study investigated the effectiveness of a range on measures to prevent air acting as a vector for bacterial dispersion in a meat processing plant.
    • Development of a critical control step for E.coli 0157:H7 in pepperoni

      Duffy, Geraldine; Riordan, Denise C.; Sheridan, James J.; US-Ireland Co-operation Programme in Agriculture Science and Technology (Teagasc, 1999-10)
      Verocytotoxin producing Escherichia coli (VTEC) and particularly strains of serogroup O157, have emerged as food poisoning pathogens which can cause a severe and potentially fatal illness. The symptoms of VTEC infection include haemorrhagic colitis with bloody diarrhoea and severe abdominal pain. The infection may lead to renal failure as a result of haemolytic uraemic syndrome. Because of the severity of the illness and the low infectious dose, this pathogen is classed as a serious food safety issue. It is recommended by the United States Department of Agriculture that the production process for ready to eat foods such as fermented meats (pepperoni, salami etc.) should be capable of addressing a worst case scenario ie. the production process should be able to yield a log105.0cfu /g (105 cfu/g) reduction in numbers of E. coli O157:H7 on the raw meat. The aim of this study was to develop an industrially viable critical control step(s) which could be implemented into the pepperoni production process.
    • Development of a novel bulk packaging system for retail cuts of meat

      Allen, Paul; Doherty, Alice M.; Isdell, Emer (Teagasc, 1999-03)
      Meat colour is an important criterion in the appeal of meat to consumers at the point of sale. The bright red colour of fresh beef and lamb and the pinkish colour of fresh pork are due to the oxygenation of the myoglobin pigment when the meat is exposed to air. However, exposure to air over several days causes irreversible browning and rejection of the meat by consumers. The gaseous environment in which retail cuts are stored is therefore critical to ensure a good colour over the display life. Existing packaging systems do not have a sufficiently long storage life for the additional time required for exports from Ireland to the UK or continental Europe. The objective of this project was to develop a bulk packaging system for retail cuts that would have a sufficient shelf life to be used by the Irish industry to export retail ready cuts. In conclusion, a packaging system has been developed on a laboratory scale which is capable of extending the storage life of some beef cuts, lamb loin chops and pork loin chops. The display life of these after storage is comparable to fresh cuts. In order for this system to be commercialised it would have to be shown to work on a larger scale in a production environment.
    • Development of a Range of Encapsulated Milk Fat Products

      Keogh, M.K.; O'Kennedy, Brendan; Neville, Denis P.; Kennedy, B.; Gorry, C. (Teagasc, 1998-09-01)
      The aims of this research were to determine the effects of milk composition (fat, whey protein, lactose and salts) and process (homogenisation) factors on the formation of emulsions and microencapsulated powder particles and to relate these to the properties of the powder, especially susceptibility to fat oxidation. The effect of composition, using sodium caseinate and lactose on the production of high fat powders was also studied. Finally, new developments in microencapsulated milk powders were undertaken in collaboration with industry using sodium caseinate and lactose. Overall, the microencapsulation process should provide a technique to extend the shelf-life of sensitive fats and flavours and to produce high fat powders for a range of end-uses. The major components of the emulsions used to make the microencapsulated powders influenced fat globule diameter and stability, but the minor salt components also affected globule size and stability. Free flowing high fat (70%) powders with sodium caseinate and lactose as encapsulants were manufactured using a tall-form Niro spray dryer with fluidised beds. A flavoured ingredient using a by-product flavoured fat as the flavour agent was made using the same encapsulants. Microencapsulated powders were incorporated into baked goods as multi-functional ingredients. They increased loaf volumes and improved handling and processability of the dough, thereby extending the product range for fat and other dairy ingredients used for baking. Microencapsulated 80% fat blends were manufactured for biscuit formulations to overcome the handling problems associated with bulk fats. This sub-project also gave rise to a leading role in a EU FAIR project on the microencapsulation of fish oil for use in functional foods using milk components as the sole encapsulants.
    • Development of HACCP analysis systems for beef slaughter

      Doherty, Alice M.; McEvoy, John M.; Sheridan, James J.; McGuire, Liam; O'Sullivan, Marian; Department of Agriculture, Food and the Marine, Ireland (Teagasc, Ballsbridge, Dublin 4, 1999-01)
      The aim of this study was to establish the types and levels of bacterial contamination on beef carcasses slaughtered under commercial conditions. This information is necessary as baseline data for the implementation of a Hazard Analysis Critical Control Point (HACCP) plan in a meat factory. Samples were taken over a twelve month period from five carcass sites representing the fore and hind quarters of the carcass. These included the hock, bung, inside round, cranial back and brisket. The carcasses were sampled at different stages of dressing namely legging, hide removal, evisceration, carcass splitting, carcass washing and chilling (24 h later). Four meat cuts (inside round, outside round, chuck roll (cranial back) and brisket) were also sampled after boning. Counts were enumerated for the following groups of bacteria: total bacterial counts (25°C and 4°C); pseudomonad counts (25°C and 4°C); E nterobacteriaceae counts; E scherichia coli O157:H7 and L isteria spp.
    • 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.
    • Development of organic breads and confectionery

      Gallagher, Eimear; Keehan, Denise; Butler, Francis (Teagasc, 2005-07)
      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.
    • Development of Technologies for Separation and Functional Improvement of Individual Milk Protein Fractions

      Stanton, Catherine; Fitzgerald, Richard J.; Donnelly, W.J.; O'Connor, Paula M. (Teagasc, 1999-02-01)
      Milk proteins can be hydrolysed (i.e. fragmented) using proteolytic enzymes to give enhanced functional and nutritional properties. There is an increasing demand for hydrolysed protein ingredients with specific properties for nutrition of individuals with specialised dietary requirements including infants, the critically ill, the immuno-compromised and athletes. Such hydrolysed proteins can be specifically designed to provide distinctive tailor-made solutions to meet customer needs in these areas. This project explored the technologies for the production of two types of hydrolysates i.e. acid-soluble and glutamine-rich. Acid-soluble protein hydrolysates have potential in the fortification of acidic beverages, including soft drinks. Glutamine-rich hydrolysates are suggested as an optimal glutamine source for administration during periods of stress, such as recovery from strenuous exercise, or from surgery. Casein was selected as the protein for development of acid-soluble product and cereal protein for the glutamine-rich product. The main conclusions were as follows: A number of protein hydrolysate products with value added properties and the processes required for their manufacture have been developed and are available for uptake by the food industry. Laboratory investigations identified conditions for the generation of two casein hydrolysates with desirable functional properties. Scale-up conditions for the manufacture of these hydrolysates in the pilot plant were successfully developed. Both hydrolystates were 100% soluble at pH 4.6, exhibited clarity in solution at low pH in clear soft drinks and in caramelised beverages and were stable in solution over a wide temperature range (from 4 to 30ºC) for extended periods. Solutions containing these hydrolysates exhibited no foaming properties and had acceptable sensory properties, being considered as weakly bitter compared to unsupplemented solutions. These performance characteristics make the acid-soluble hydrolysates useful supplements for caramelised beverages, such as colas, and clear soft drinks. Six glutamine-enriched peptide products were produced at laboratory scale using two commercially available enzyme preparations. These products had desirable characteristics such as increased levels of peptide bound glutamine, low free amino acid and free pyroglutamate levels. Pilot plant processes were developed for manufacture of the two glutamine-rich hydrolysates with most suitable compositional properties and these were fully characterised chemically. The manufacturing process was modified to enable industrial scale batches (5,000 litres) to be produced.
    • Development of value-added beef products

      Desmond, Eoin; Troy, Declan J.; Kenny, Tony; McDonagh, Ciara; Ward, Patrick (Teagasc, 2001-05)
      This work investigated technologies to improve the functionality of beef, particularly low-value beef to increase its versatility for the development of value-added restructured and emulsion type beef products. More specifically the project objectives were (1) to increase the functionality of beef; (2) to develop innovative beef products; (3) to increase the use of low-value carcass cuts as a functional ingredient in beef products. The research was carried out in three stages: solubilisation of connective tissue components of beef using organic acids, application of proteases to beef model systems to increase functionality, and physical disruption of connective tissue in beef by mechanical treatments such as needle and blade tenderising, tumbling and massaging.
    • Effect of Milk Composition on the Quality of Fresh Fermented Dairy Products

      Wilkinson, M.G.; Guinee, Timothy P.; Fenelon, Mark A. (Teagasc, 2000-09-01)
      The rheology of yogurts or fresh fermented products generally describes and measures the texture of the product and includes such terms as viscosity and firmness of the gel while syneresis refers to the tendency of the yogurt to whey-off during storage. The importance of rheology and susceptibility to syneresis of fermented milk products is that they both have major impacts on consumer perceptions of the final product quality. Indeed, variation in the quality of yogurt products can lead the consumer to experience either an over-thin watery or an over-thick stodgy texture or a product which has a high level of free whey. It is obvious that the seasonal milk supply in Ireland compounds the particular difficulties associated with achieving a consistency in the quality of yogurts or other fresh fermented products. Importantly, both the rheology and syneresis of yogurts are markedly influenced by milk composition, processing treatments and the addition of hydrocolloids. Therefore, this project was undertaken so as to develop a laboratory fermented milks model system which allows the evaluation of the effects of variation of milk components, individually or in combination, on the rheological and syneretic properties of fermented milk products such as yogurt. In particular, the effects of varying total protein, casein-to-whey protein ratio, and fat content were studied as these variations reflect both the differences in milk composition due to lactational/seasonal effects and those due to process variations such as milk heat treatment.
    • The Effect of Nutrition on the Flavour of Strawberries Grown Under Protection.

      MacNaeidhe, F. S. (Teagasc, 2001-07-01)
      The superior flavour of strawberries grown in the brown earth soils in Ireland compared with those grown on podsolics derived from calcium rich chalk has been recognised by UK wholesalers for some time. The strawberry variety Elsanta is the most common variety grown in both regions and it is reasonable to conclude that environmental factors especially soil type are mainly responsible for the superior flavour of strawberries grown on brown earth soils. The differences in soil pH, calcium and potassium concentrations were used as the main basis in drafting a research project investigating the effect of nutrition on the flavour of strawberries. A research project on the effect of nutrition on the flavour of strawberries under protection was undertaken at Clonroche in 1997.
    • The Effects of Processing and Ripening on the Quality of Pizza Cheese

      Guinee, Timothy P.; Mulholland, E.; Mullins, C.; Corcoran, M.O.; Auty, Mark (Teagasc, 1999-02-01)
      The main aims of this project were to quantify the changes in fuctionality during maturation of cheese and to develop an understanding of the factors which mediate the development of functionality. The approach to achieving these objectives involved the establishment of a suitable pilot plant production procedure for low moisture Mozzarella, developing and/or adapting existing methods for objective evaluation of the functional properties of pizza cheeses, and evaluating the effects of ripening and variations in cheesemaking conditions (e.g. pH at stretching) on the composition, yield and functionality of low moisture Mozzarella cheese. The main conclusions were as follows: The technology for developing low moisture Mozzarella cheeses, with different compositions and functionalities, via alteration of cheesemaking parameters, has been developed. A database has been established on the storage-related changes that occur in texture, proteolysis and functionality of low moisture Mozzarella cheeses of different compositions. In addition an extensive database on the compositional, biochemical, microstructural, rheological and/or functional properties of different commerical cheeses - low moisture Mozzarella, Cheddar and analogue pizza cheese, has been compiled. The functionality of low moisture Mozzarella changes markedly on storage/ripening at 4ºC. Initially, during the first 5-10 days of storage, the functionality of the baked cheese is poor but then improves on further storage as reflected by reductions in melt time and apparent viscosity (chewiness) and increases in stretchability and flowability. The changes in functionality are mediated by storage-related increases in pH, proteolysis, protein-bound water and free oil in the cheese. On prolonged storage (e.g. > 60 d at 4ºC), the cheese functionality becomes impaired as the shredded cheese develops an increased susceptibility to clumping/balling which makes it difficult to dispense the cheese onto the pizza pie and achieve a uniform surface distribution. Moreover, the baked cheese tends to exude excess free oil and loses its desired level of chewiness attaining a 'soupy' consistency. Novel methods were developed/adapted to objectively quantify functionality in the raw (susceptibility of shredded cheese to clump) and cooked (stretchability, chewiness, viscoelasticity) cheeses.