Pectin, a complex polysaccharide rich in galacturonic acid, has been identified as a critical structural component of plant cell walls. The functionality of this intricate macromolecule in fruit- and vegetable-based-derived products and ingredients is strongly determined by the nanostructure of its most abundant polymer, homogalacturonan. During food processing, pectic homogalacturonan is susceptible to various enzymatic as well as nonenzymatic conversion reactions modifying its structural and, hence, its functional properties. Consequently, a profound understanding of the various process-structure-function relations of pectin aids food scientists to tailor the functional properties of plant-based derived products and ingredients. This review describes the current knowledge on process-structure-function relations of pectin in foods with special focus on pectin's functionality with regard to textural attributes of solid plant-based foods and rheological properties of particulated fruit- and vegetable-derived products. In this context, both pectin research performed via traditional, ex situ physicochemical analyses of fractionated walls and isolated polymers and pectin investigation through in situ pectin localization are considered.

The effect of thermal processing on the stability of beta-carotene in carrot puree was investigated in a broad temperature range (80-150 degrees C). Heat induced changes in the stability of beta-carotene resulting in the conversion into its cis-isomers until an equilibrium state was reached after prolonged heating. By using nonlinear one-step regression analysis, the overall isomerization of all-trans-beta-carotene and the formation of individual cis-isomers could be modeled with a fractional conversion model. The Arrhenius equation was used to describe the temperature dependence of the reaction rate constants. As indicated by the low activation energies for all compounds (11 kJ mol(-1)), the isomerization rate constants showed little sensitivity toward the treatment temperature. The temperature dependence of the equilibrium concentration values after prolonged heating (C(f)) varied for the different compounds, but in all cases, a linear relation between the C(f) values and the treatment temperature could be noted. Although isomerization was observed as a result of thermal processing, it could be concluded that during industrially relevant heating processes, the retention of all-trans-beta-carotene in plain carrot puree was relatively high, which is most likely due to the presence of the protecting food matrix.

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DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:

Document VersionAccepted manuscript including changes made at the peer-review stage Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication Citation for published version (APA):Moelants, K. R. N., Jolie, R. P., Palmers, S. K. J., Cardinaels, R. M., Christiaens, S., Van Buggenhout, S., ... Hendrickx, M. E. (2013). The effects of process-induced pectin changes on the viscosity of carrot and tomato sera. Food and Bioprocess Technology, 6(10), 2870-2883. DOI: 10.1007/s11947-012-1004 General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 2 Abstract 11The influence of process-induced pectin changes on the kinematic viscosity of the serum phases 12 of carrot and tomato purées was investigated in this study. Variations in the amount of pectin 13 present in the serum phase and pectin's fine structure were induced by subjecting carrot and 14 tomato to different thermal treatments, i.e. a mild and a strong heat treatment, followed by 15 blending and high-pressure homogenisation at different pressure levels (0, 20 and 100 MPa). 16Changes in pectin structure were monitored by determination of the degree of methoxylation, 17analysing the molar mass distribution and immuno-dot blotting using anti-pectin antibodies. 18Characterisation of serum pectins revealed that a strong thermal treatment caused pectin

Nowadays, there is much interest in controlling the functional properties of processed fruit-and vegetablederived products, which has stimulated renewed research interest in process-structure-function relations. In this review, we focus on rheology as a functional property because of its importance during the entire production chain up to the moment of consumption and digestion. This review covers the literature of the past decade with respect to processstructure-rheology relations in plant-tissue-based food suspensions. It became clear that the structure of plant-tissue-based food suspensions, consisting of plant-tissue-based particles in an aqueous serum phase, is affected by many unit operations (for example, heat treatment) and that also the sequence of unit operations can have an effect on the final structural properties. Furthermore, particle concentration, particle size, and particle morphology were found to be key structural elements determining the rheological properties of these suspensions comprising low amounts of starch and serum pectin. Since the structure of plant-tissue-based products was shown to be changed during processing, rheological parameters of these products were simultaneously altered. Therefore, this review also comprises a discussion of the effect on rheological properties of the most relevant processing steps in the production of plant-tissue-based products. Linking changes in rheology due to processing with process-induced alterations in structural characteristics turned out to be quite intricate. The current knowledge on process-structure-function relations can form the basis for future improved and novel food process and product design.

To study the effect of particle size on the relative all-E-β-carotene and all-E-lycopene bioaccessibility in carrot- and tomato-derived suspensions, respectively, an in vitro digestion approach including oil was used. Adding olive oil (2%) during digestion, especially as an oil-in-water emulsion, resulted in a substantial increase in carotenoid uptake in the micellar phase. Carotenoid bioaccessibility decreased with average particle size. Only particles smaller than an individual cell resulted in high bioaccessibility values, pointing out the importance of the cell wall as the main barrier for carotenoid uptake. The relation obtained between particle size and bioaccessibility was used to predict the carotenoid bioaccessibility in carrot- and tomato-derived purées. These predictions indicated that carotenoid bioaccessibility in plant-based food suspensions is not only determined by the cell wall integrity (related with particle size) but is also affected by interactions between the structural compounds of the complex food matrix.

Document VersionAccepted manuscript including changes made at the peer-review stage Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publicationCitation for published version (APA): Moelants, K. R. N., Cardinaels, R. M., Jolie, R. P., Verrijssen, T. A. J., Van Buggenhout, S., Zumalacarregui, L. M., ... Hendrickx, M. E. (2013). Relation between particle properties and rheological characteristics of carrotderived suspensions. Food and Bioprocess Technology, 6(5), 1127-1143. DOI: 10.1007/s11947-011-0718-0 General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. The effect of particle properties on the rheological behaviour of carrot-derived suspensions was 15 investigated systematically. Hereto, a range of relative monodisperse suspensions, with varying 16 average particle size (~73, 176, 262 and 369 µm) and pulp content (from 30 to 65 w%), was 17 prepared by the reconstitution of carrot tissue particles in water. Suspensions with average 18 particle size of ~73 µm consisted of cell fragments whereas suspensions with larger particle sizes 19 contained mainly cell clusters of which the cell number increased with increasing particle size. 20The rheological characteristics showed that the carrot-derived suspensions have a non-21Newtonian behaviour with a yield stress, depending on particle concentration, size and type). 22The network structure of all suspensions could be described as a weak gel. Increase in yield 23 stress and storage modulus with particle concentration could be fitted to a power law model. A 24 unique linear relation was found between the yield stress and the plateau modulus, independent 25 of the particle size and type. Particle concentration, size and type appeared to be key structural 26 pa...