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chapters) to specific dairy products (11 chapters),and then on to the more general topics of nutrition,research and development (R&D), packaging andprocessing (4 chapters). The final two chapters dealwith safety and quality, and laboratory analysis, toround off a very comprehensive book on dairyprocessing. Each chapter is well illustrated withdetailed tables and figures, has its own referenceand/or bibliography section, and the references areup-to-date. It is pleasing to note that each chapterdealing with a specific product group also includesa section on the quality control relevant to thatproduct. The book is packed with specific andrelevant detail on each page yet is at the same timereadable, with each chapter having that author’sstamp of individuality.

Whilst it would be impossible to précis eachindividual chapter, such is the wealth of data includedin each chapter, the following chapters are high-lighted. Chapter 1 sets the scene with a wide-rangingintroduction, yet with much interesting detail andbackground, e.g. the basis of colour and flavour inmilk arising from specific feeds. It is interesting thatthere is only a minor reference in the whole bookto the environment; in this chapter a brief mentionis made of effluent disposal, but the concept ofIntegrated Pollution Prevention and Control (IPPC)is not covered. However, the impact of environ-ment on packaging is well discussed in Chapter 20.

Chapter 2 gives basic production and consump-tion data worldwide, but the major part of thechapter is devoted to a review of the dairy industryin the USA, excellent in itself but without anyallusion to trends in the wider world. The restric-tion to USA-based information is also evident inthe chapters on labelling and farm-to-processordata, so the reader looking for the wider picturewill be disappointed. The scientific chapters, 3 to 5,are comprehensive, e.g. the ‘Table’ on spoilage andpathogenic micro-organisms relevant to the dairyprocessor is very detailed, with some mentionmade of Mycobacterium avium subsp. paratuber-culosis (MAP), including the excellent work donein the European Union (EU) countries.

The chapters on processing are detailed andcover: fluid milks, cultured milk and yoghurt,butter and spreads, cheeses (i.e. with an emphasison hard-pressed cheese rather than fresh and softcheeses), evaporated milks, milk powders, wheyproducts, ice-cream and desserts, and puddingsand dairy-based desserts, most with an Americanbias. By way of contrast, butter and spreads(Chapter 11) by researchers from the UnitedKingdom (UK) Australia gives a refreshingwhole-world review of this area, which has seenthe introduction of many innovative spreadablebutters, low-fat and blended spreads.

There are good worked examples of calculationsfor students in the processing chapters, e.g. for

standardisation of fluid milks and the formulationsof ice-cream and desserts mixes.

The role of milk and dairy products in thenutrition and health of humans is reviewed fully inChapter 18, with the basis of beneficial effects welldescribed, although there is no mention of specificfunctional dairy product(s) in any of the main con-sumer markets.

One of the most important chapters is entitledproduct development strategies—Chapter 19; thisdiscusses the crucial elements of the innovationstrategy which must be present if a company is tobe successful, including a multi-gate developmentprocess. A comparison is made between the USAand Europe in the varying importance of severalfactors influencing success of new product devel-opment, a chapter well worth reading to ensureeffective R&D in any company.

The chapters on packaging and non-thermalprocessing are wide-ranging and include recentdevelopments, e.g. extended shelf-life packagingand high pressure processing, respectively.

The penultimate chapter, management systemsfor safety and quality—Chapter 22, describes thehazard analysis critical control point (HACCP)system in much detail. All the relevant informationis based on data from the Federal and DrugAdministration (FDA) perspective, with no refer-ence to other equally valid worldwide regulatoryapproaches, such as ISO 22000. There is fulldescription of the history and functions of theCodex Alimentarius Commission.

The concluding chapter, Laboratory Analysis—Chapter 23, is comprehensive, with good detail onsampling plans and areas to be included, althoughthe microbiology is classical in the methodsapplied, and there is no mention of the newerbio-luminescence (ATP) approaches, which arenow commonplace.

This book will be a very useful addition to thelibraries of academia and industry alike, and I wouldrecommend it highly across the world, and parti-cularly to those working in the USA dairy industry.

I.A. McDougallR_and_D.McD@ntlworld.com

Determination of Omega-3 and Omega-6Fatty Acid Content by Gas-Liquid Chromato-graphy in Milk Fat From Enriched Products—Interlaboratory Collaborative Studies (2008),Bulletin No. 428, International Dairy Federation,Diamant Building, 80 Boulevard Auguste Reyes,B-1030 Brussels, Belgium. ISSN: 0250-5118.Price: a18.00

There is nowadays a variety of dairy productsfortified with omega-3 and omega-6 polyunsaturated

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fatty acids in the marketplace. Infant formulasand related preparations, such as growing-up milks,are one of the main product categories in whichpolyunsaturated fatty acids are added to ensureadequate intake during early stage of life. Besidesthese specialities, various fermented and non-fermented dairy products have been launched withthe intention of providing nutritionally importantfatty acids required for balanced nutrition. Theseproduct ranges are aimed at healthy children andadults, as well at specific targets such as expectantor breastfeeding mothers.

Bulletin 428 describes a method suitable fordetermining the concentrations of different fattyacids from the omega-3 and omega-6 series indairy products fortified with marine oils or poly-unsaturated vegetable oils. Both the developmentand validation were performed in different labora-tories in Italy. The quality and reliability of thisanalytical method has been assessed by complet-ing an international inter-laboratory collaborativetest. All the data are reported in details in thebulletin.

The levels of polyunsaturated fatty acids addedto the products are low, and correspond to a fractionof the daily recommended intake. The ingredientsused as sources of polyunsaturated fatty acids indairy products are marine, vegetable or single celloils. Milk fat is by far one of the most complexsources of fatty acids, and therefore the precisequantification of fatty acids in conventional dairyproducts is challenging. This challenge becomeseven more important when sources of polyunsatu-rated fatty acids are added at low levels in dairyformulation. There is, therefore, a need and demandfor reliable analytical methodology suitable forquantifying polyunsaturated fatty acids from theomega-3 and omega-6 families in dairy products.

In this Bulletin, all the experimental conditionsfor sample preparation and analysis are reported.The specific requirement of the method is to providethe absolute concentrations of polyunsaturated fattyacids expressed as mg of polyunsaturated fattyacid per g of fat or product. Special conditions havebeen developed to prevent oxidative degradation ofthe polyunsaturated fatty acids during fat extrac-tion. Methyl tricosanoate has been selected as theinternal standard, and various chromatographicconditions allowing the separation of the targetettedmolecules or moieties are provided. It is regrettablethat the quantification of arachidonic acid is notdiscussed in this report. Arachidonic acid is oftenadded in starter infant formulas and even some-times in growing-up milks. Chromatographicseparation of methyl arachidonate acid and methyltricosanoate can be critical, but is achievable usingthe capillary column described in the bulletin.Therefore, it appears that the method can also beused to quantify arachidonic acid in infant formulas.

Bulletin 428 will be of considerable value tothose involved in fatty acid quantification in dairyproducts, and especially for both private qualitycontrol and governmental laboratories.

Frédéric DestaillatsFrédéric.Destaillats@rdls.nestle.com

Physiological and Functional Properties ofProbiotics (2008), Bulletin No. 429. InternationalDairy Federation, Diamant Building, BoulevardAuguste Reyes, B-1030 Brussels, Belgium. ISSN0250-5118. Price: Free of charge.

This short Bulletin (pp. 6) was prepared byA. Mercenier (CH), I. Lenoir-Wijnkoop (FR) andM.E. Sanders (USA).

While there is widespread agreement that probioticstrains are safe, stable and effective, there is a lackof any substantiated correlation between findingsof the variety of assay methods, either in vitro orin animal models, used in the selection of newprobiotic strains, and tests which would supportthe clinical trails necessary to make health claims.Limited knowledge of the mechanisms underlyingthe purported health benefits of probiotics makesthe design of validated screening assays particu-larly challenging, given the wide array of humanecosystems and physiological functions where aparticular strain of probiotic organism would impact.Further complications arise from the so far poorlyunderstood interactions within a given ecosystem.

A project group of 25 experts under the Interna-tional Dairy Federation/International StandardsOrganisation (IDF/ISO) Joint Action team on Pro-biotics, operating under the IDF Standing Commit-tee on Microbiological Methods of Analysis, metto list the physiological and functional propertiesrequired of probiotic bacteria, and to establishmethods to assess these functions. However, theconclusion was reached that because the potentialscope of physiological activities is so broad, nounique test or battery of tests could be defined thatwould be essential to all probiotic applications. Asthere is currently no solid documentation thatstrains which perform well in physiological tests,perform any better in human evaluations thanstrains which perform poorly in these tests. It wasconsidered premature to establish StandardOperating Procedures for limited numbers offunctional assays, considering the current statusof research but, where health claims were con-cerned, the project group recommended that twoindependent double-blind placebo-controlledclinical trails should be carried out with the finalprobiotic product and in the targeted population.

Under good practice guidelines, recommenda-tions for evaluating the strength of support of