• Ingredient Development using a Pilot-Scale Tall-Form Spray Drier

      Kelly, Philip M; Kelly, J.; Harrington, D. (Teagasc, 1998-02-01)
      The main objectives of the project were to establish relationships between process variables and product physicochemical/functional characteristics in the course of processing and drying new dairy-based ingredients such as high-fat and protein-rich products in regular and agglomerated forms. By establishing processing protocols, R&D users of the ingredient drying facilities of Moorepark Technology Ltd may be able to predict the process variables necessary for desired end-product specifications to be achieved, and thus make experimentation more efficient and cost effective, as well as facilitate small scale production runs and sample preparation for market development purposes. Particular emphasis was placed on the development of high fat cream and fat-filled powders, flavour-delivery systems and protein-enriched ingredients. The major achievement of this project is that it is now possible to confidently select the appropriate processing conditions during the spray drying of ingredients in order to attain desired end-product specifications. Based on the use of the newly-installed Tall-form drier, the project succeeded in correlating the effects of process parameters of this technicallyadvanced pilot plant with the physicochemical properties of powders containing varying fat (20-80%) and protein contents. In general, the physicochemical characteristics of fat-filled and cream-filled powders with similar fat contents were similar except for higher solubility index values (range 0.1-0.6) in the case of the former particularly in the range 26-28% fat. Furthermore, the free fat content of powders may now be controlled much more precisely using an appropriate combination of total fat, atomiser nozzle selection and post-drying blending.
    • Novel Milk Protein Ingredients.

      Kelly, Philip M; O'Kennedy, Brendan; Cribbin, M. (Teagasc, 2001-05-01)
      The manufacture of casein/caseinates containing whey protein is immediately attractive due to its potential to enhance product yield. However, some technologies capable of producing these products are ineligible for manufacturing subsidy because of restrictions pertaining to relevant EU regulations. Other emerging technologies require refinement and process design before implementation at industrial level. Furthermore, the implications of incorporating virtually the entire complement of whey protein in what is essentially a caseinate ingredient needs to be investigated carefully in terms of the versatility of use in a wide range of food formulations. The development is significant in the context of U.S. market changes - traditionally, an important outlet for Irish casein exports amounting to 20,000 - 27,000 t per annum. Ireland accounts for ~ 30% of EU casein/caseinate production with the greater proportion in Rennet form (27,000 t) and the remainder (18,000 t) as Acid casein. In recent years, a new market for a related casein ingredient - milk protein concentrate (MPC) opened up in the US, and accounted for total imports of 40,000 t in 1998, 10,000 t of which were exported from Ireland. However, this market is more restricted due to regulatory changes introduced in response to the perceived threat of MPC imports to the US dairy industry. Since casein, or its derivative products such as milk proteinate (EU Annex III compliant), are not perceived to be in competition with local milk supplies and dairy ingredients, it is now hoped that Irish casein manufacturers may be able to reclaim recently lost markets through the introduction of an innovative proteinate ingredient which is expected to command a premium in nutrition applications e.g. in sports, infant formula and nutraceutical products. With a choice of emerging new technologies for the production of novel casein-related ingredients, the dairy industry has an opportunity to decide on what is appropriate for the defence of its market share and at the same time benefit from simultaneous compliance with relevant regulatory supports (EU) and market access rules (USA). Hence the main aims of this project were: * To investigate new technologies for the isolation of casein and casein/whey protein combinations in the course of developing new milk protein ingredients, and * To compare the performance in selected food formulations of novel milk protein ingredients namely milk proteinates, milk protein concentrates, native phosphocasein and classical Annex III casein products.
    • Nutritional Studies on Dried Functional Food Ingredients Containing omega-3 Polyunsaturated Fatty-Acids.

      Kelly, Philip M; Keogh, M.K.; Kelly, J.; O'Kennedy, Brendan; Murray, C.A. (Teagasc, 2000-10-01)
      The nutritional benefits of fish oils are generally attributed to their content of long chain omega-3 polyunsaturated fatty acids (PUFAs). Diets rich in these fatty acids are known to reduce the risk of coronary thrombosis, and are recommended to those who are susceptible to atherosclerosis. In addition, some of these long chain PUFAs play an important role in early infant nutrition, in the development of vital human organs such as the neural tube. However, practical difficulties arise in achieving an adequate daily intake of fish oils to obtain these physiological benefits. Per capita fish consumption is low in many countries, especially of oily fish with high levels of omega-3 PUFAs. Fish oil, while available as a dietary supplement, is not universally appealing in that form. Attempts to incorporate fish oil into food formulations have had limited success mainly because of fishy flavours coming through in the consumer products. Fish oil is particularly susceptible to oxidation, which results in fishy, painty and metallic flavours. Hence the main aim of this study was the development of a dried ingredient in which the formulation and related processing conditions were optimised to protect the fish oil from oxidation. Protection of any sensitive oil may be achieved by means of microencapsulation, whereby oil is dispersed as very fine droplets in emulsions. During subsequent spray drying the droplets are effectively sealed inside a protective coating of protein surrounded by carbohydrate. The objective was, therefore, to evaluate microencapsulation as a means of extending the shelf-life of fish oil in powder form thus increasing its versatility as a nutritional ingredient in food formulations.
    • Optimisation of Ingredient Formulation in Processed Meat Products.

      O'Kennedy, Brendan; Neville, Denis; Kelly, Philip M (Teagasc, 2000-10-01)
      Reformed and restructured meat are two major categories of processed meat products. Reformed meat products require intact meat pieces to bind together while restructured meat products are extensively minced prior to restructuring. Salts such as sodium chloride and phosphates together with mechanical treatment and heat, have been used to bind meat pieces together. In the process the proteins in muscle become soluble, bind large amounts of water and gel on heating. While heat-induced gelation of soluble meat protein provides binding in reformed meat products and reduces cook losses in restructured meat products, no binding occurs in raw meat systems. Non-meat proteins, especially soya protein, are routinely used in processed meat products, often in conjunction with salts, to increase water and fat binding during the cooking process. However, such proteins do not bind intact meat pieces in either the raw or cooked state. Transglutaminase (TGase) is a food-grade commercially available enzyme which can crosslink suitable proteins leading to the formation of a protein matrix (gel) and immobilisation of large quantities of water. This property could improve the water-binding properties of non-meat proteins in restructured meat products. The prospect of crosslinking native meat proteins and non-meat proteins or native meat proteins on adjacent meat pieces would make salt-free reformed meat products a realistic objective. Hence, the main objective of this project was to study protein-protein interactions in reformed and restructured meats, especially between meat proteins and added non-meat proteins in the absence of salts but in the presence of a protein crosslinking enzyme.