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Belscak-Cvitanovic A.,University of Zagreb | Levic S.,University of Belgrade | Kalusevic A.,University of Belgrade | Spoljaric I.,Forensic Science Center Ivan Vucetic Zagreb | And 4 more authors.
Food and Bioprocess Technology | Year: 2015

In this study a bottom-up approach of designing functional ingredients from green tea extract is proposed by a systematic investigation of 12 different natural biopolymers and their efficiency as carrier materials of green tea bioactive compounds by spray drying at low temperature (130 °C). Screening of carriers revealed that inulin and whey proteins provide the highest product yields (67.04 and 65.18 %, respectively) and, accompanied with pectin, also the highest total polyphenols (67.5–82.2 %) and flavan-3-ols (93.7–75.9 %) loading capacity. Up to 162 mg/g of (−)−epigallocatechin gallate (EGCG) was achieved, while low-caffeine contents (<5 mg/g) indicated the potential of obtaining low-caffeine functional ingredients. Employing alginate, carageenan and gums (acacia gum and xanthan) enabled the best colour preservation and highest chlorophyll content. Reconstituted green tea microencapsulates comprising modified starch, inulin or carageenan exhibited the lowest bitterness and astringency and the highest green tea flavour intensity as the most favourable sensory properties. An artificial neural network (ANN) designed based on the experimentally obtained results revealed hydrocolloid gums as the best encapsulants for achieving good physical properties, high EGCG contents and prolonged dissolution/release profiles while pectin, inulin and modified starch as the optimal ones in terms of the product yields, loading capacities and sensory properties. This indicates that a formulation comprising a combination of all of those biopolymers would provide potentially functional ingredients with encapsulated green tea phytochemicals, retained colour and improved sensory properties. © 2015 Springer Science+Business Media New York

Belscak-Cvitanovic A.,University of Zagreb | Busic A.,University of Zagreb | Barisic L.,University of Zagreb | Vrsaljko D.,University of Zagreb | And 5 more authors.
Food Hydrocolloids | Year: 2016

This research underlines the potential of employing emulsion/internal gelation encapsulation in alginate and pectin hydrogels for the simultaneous delivery of hydrophilic (polyphenols from dandelion (Taraxacum officinalis L.) extract) and lypophilic (β-carotene) compounds. The approach of reinforcing alginate and pectin hydrogels by whey proteins and hydroxypropyl methylcellulose (HPMC) as the carriers for the design of microencapsulated delivery systems was also evaluated. Comprehensive characterization of the morphological properties, particle size, encapsulation efficiency, interactions and release in gastrointestinal conditions was achieved. A simple and effective procedure based on the ionic gelation of emulsions for microencapsulation of polyphenols and β-carotene was developed, allowing formulation of micro-sized particles ranging ≤800 μm, which retained their spherical morphological properties upon drying. Incorporation of whey proteins and HPMC in the alginate gel contributed to better encapsulation parameters i.e. the morphological properties and encapsulation efficiency in relation to plain alginate particles. The combination of alginate with whey proteins as the carrier matrix arised as the optimal delivery system, owing to its regular, spherical shape, high encapsulation efficiency of total polyphenols (77,35%) and very good retention of hydroxycinnamic acids (89,14%), while the binary mixture of alginate and HPMC as the carrier enabled the best (prolongued) release profile of these compounds from the formulated microparticles in simulated gastrointestinal fluids. © 2016 Elsevier Ltd.

Belscak-Cvitanovic A.,University of Zagreb | Komes D.,University of Zagreb | Karlovic S.,University of Zagreb | Djakovic S.,University of Zagreb | And 3 more authors.
Food Chemistry | Year: 2015

Alginate-based blends consisting of carrageenan, pectin, chitosan or psyllium husk powder were prepared for assessment of the best formulation aimed at encapsulation of caffeine. Alginate-pectin blend exhibited the lowest viscosity and provided the smallest beads. Alginate-psyllium husk blend was characterised with higher viscosity, yielding the largest bead size and the highest caffeine encapsulation efficiency (83.6%). The release kinetics of caffeine indicated that the porosity of alginate hydrogel was not reduced sufficiently to retard the diffusion of caffeine from the beads. Chitosan coated alginate beads provided the most retarded release of caffeine in water. Morphological characteristics of beads encapsulating caffeine were adversely affected by freeze drying. Bitterness intensity of caffeine-containing beads in water was the lowest for alginate-psyllium beads and chitosan coated alginate beads. Higher sodium alginate concentration (3%) for production of hydrogel beads in combination with psyllium or chitosan coating would present the most favourable carrier systems for immobilization of caffeine. © 2014 Elsevier Ltd. All rights reserved.

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