See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/23663540 Effect of the Temperature on the Spray Drying of Roselle Extracts (Hibiscus sabdariffa L.) Article in Plant Foods for Human Nutrition · December 2008 Impact Factor: 1.98 · DOI: 10.1007/s11130-008-0103-y · Source: PubMed CITATIONS READS 26 532 4 authors: Salvador González-Palomares Mirna Estarrón-Espinosa Consejo Nacional de Ciencia y Tecnología Centro de Investigación y Asistencia en Tec… 47 PUBLICATIONS 52 CITATIONS 42 PUBLICATIONS 287 CITATIONS SEE PROFILE SEE PROFILE Juan F. Gomez-Leyva Isaac Andrade-González Instituto Tecnológico de Tlajomulco Instituto Tecnológico de Tlajomulco 21 PUBLICATIONS 110 CITATIONS 19 PUBLICATIONS 106 CITATIONS SEE PROFILE All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately. SEE PROFILE Available from: Juan F. Gomez-Leyva Retrieved on: 27 May 2016 This classifies the spray drying method as the best alternative to obtain colorants and natural powder flavoring [14–16]. An acceptS. Gómez-Leyva e-mail: jfgleyva@hotmail. Gonzalez-Palomares e-mail: chava1142@yahoo. San Miguel Cuyutlán. Fourteen volatile compounds were identified in the powder sample.4 to 3. Gonzalez-Palomares : J. The Roselle extraction was carried out by maceration with 7 L of 30% ethanol (v/v). 180. Nevertheless. The obtaining of Roselle powder through spray drying is an important alternative method for the use of the calyces [11–13]. transportation and shelf-life. Sensory analysis . CP 45640 Tlajomulco de Zúñiga. ascorbic acid and anthocyanin color [1– 3].) Salvador Gonzalez-Palomares & Mirna Estarrón-Espinosa & Juan Florencio Gómez-Leyva & Isaac Andrade-González Published online: 10 December 2008 # Springer Science + Business Media. but only ten were present in the Roselle extract.. 160. 190. Colinas de la Normal. Estarrón-Espinosa Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco.C. Jal.com M. esters. México e-mail: isaacag2001@yahoo.. Spray dryer . Gómez-Leyva : I. giving different outlet values about yield and final moisture. 800. Keywords Roselle powder .9. LLC 2008 Abstract The effect of the drying temperature on the volatile components and sensory acceptance of the Roselle (Hibiscus sabdariffa) extract in powder was investigated.1007/s11130-008-0103-y ORIGINAL PAPER Effect of the Temperature on the Spray Drying of Roselle Extracts (Hibiscus sabdariffa L. Andrade-González (*) Graduate and Research Studies Department.mx J. 10 Carr. México e-mail: [email protected]. 170.net. 560 g of fresh Roselle calyces for 168 h. the Roselle calyces are utilized as a good source of natural food colorants by their high natural pigment content [4–6].05). The dehydrated products then can be added easily to other foods to improve their storage. This indicates that some compounds were lost and some others were generated due to a degradation process. antitumor and anticarcinogenic activity [7–9].Plant Foods Hum Nutr (2009) 64:62–67 DOI 10. Km. Instituto Tecnológico de Tlajomulco. Hibiscus sabdariffa anthocyanins are unstable during the heat treatments. Volatile components Introduction Roselle calyx (Hibiscus sabdariffa) is the plant part of greatest interest because the calyx is utilized in the processing of fruit preserves. The volatile compounds in Roselle extract and dried samples were performed using needles of solid phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS HP-5890). Hibiscus sabdariffa anthocyanins have been reported to possess antioxidative. Jal. Twenty volatile compounds were identified in the extracts among them terpenoids.mx S. A.mx ability sensory analysis showed that the best powder sample was the Roselle extract dehydrated using temperature between 190 °C and 200 °C (p<0.. F.com. The Roselle extracts were spray dried at different temperatures 150. Many studies on Roselle (Hibiscus sabdariffa) powder have been focused on the factors that are influencing the reconstitution characteristics . therefore studies on drying process conditions are requested in order to achieve the best stability of the final product [10]. Today. 200 and 210 °C. It was concluded that the spray drying temperature of the Roselle extracts has an effect on the volatile compounds losses. There was not statistically significant difference in the pH of Roselle extracts ranging from 3. hydrocarbons and aldehydes. jellies and jams for its rich content in pectin. Normalistas No. In addition. CP 44270 Guadalajara. F. Av. 180. Reconstitution of Roselle Powder The reconstituted samples were carried out by placing a portion of Roselle powder in 300 mL of distilled water. Six grams of each sample were placed in an aluminum dish and introduced in a vacuum stove with a temperature of 40 °C until the weight remained constant. 22]. Operating conditions for GC/ MS were: the oven temperature was programmed at 40 °C . The HP5890 chromatograph was equipped with HP-1 (50 m×0. A flexible plastic tube was inserted inside one container and connected to a variable flow peristaltic pump. 160. The characteristics of the roselle extracts were 22% of soluble solids and pH of 3. the macerated extracts were filtered through a 150 μm mesh. The standardization of the mixture was carried out in all the samples until reaching the same concentration of soluble solids of the liquid extract (22%) [12]. The vial was fitted with a PTFE-faced silicone septum and put in a thermostatted bath.2 mm ID×0. An ATAGO refractometer was used to determine the percentage of soluble solids. 190. 200 and 210 °C. The objective of this work was to evaluate the effect of the spray drying temperatures on the Roselle extracts (Hibiscus sabdariffa L. The outlet temperature was fixed in 80 °C and the atomization was kept at 37. In spite of the knowledge that the volatile compounds show low stability at the spray drying temperatures. Supelco. the extraction of volatile substances by micro extraction in a solid phase (SPME). Mexico during October and November 2006. After.788×g. all under constant conditions of static maceration. The content was left in maceration for 168 h with an occasional shaking to increase the extraction capacity at room temperature. A HewlettPackard 5890 Series II gas chromatograph with flame ionization detector (FID) coupled to 5972 MSD quadrupole mass spectrometer was used. only scare studies have been reported on this issue for volatiles in Roselle [6]. in addition of anthocyanin concentrates and the processing conditions. The roselle extracts were kept under refrigeration at 4 °C. and physicochemical characteristics of the powder produced [12].Plant Foods Hum Nutr (2009) 64:62–67 or the effects of some additives and processes on characteristics of agglomeration and granulation. An ORION potentiometer was used to measure the pH. 170. changes on the spray drying temperature can affect the concentration of volatile compounds which would generate the loss of some sensorial characteristics [17–20]. 150. The Roselle powder samples obtained by spray drying were weighed and packed in their respective amber-coloured glass flasks of 100 mL. the quantitative and qualitative analysis by gas chromatography and mass spectrometry (GC-MS) as well as sensorial assays are useful tools in the evaluation of the effect of certain process variables about the quality of the dehydrated products [23–26].33 μm film thickness) a capillary column. Spray Drying A NIRO spray dryer (with the capacity to evaporate 40 kg of water per hour) with a wheel rotating atomizer was used 63 for the spray drying process in all the experiments. For this reason.4. the retention of the volatile compounds and the sensorial acceptance of the reconstituted spray dried samples. A Büchi rotavapor was used to concentrate the samples and to separate all the ethanol at 40 °C.). A fiber coated with 50/30 mm of divinylbenzene/carboxen on polydimethylsiloxane (DVB/ Carboxen/PDMS. The flexible outlet tube from the pump was directly connected to the liquid fed inlet of the atomizer. The reconstituted samples were stored in amber-colored glass flasks and refrigerated until their analysis. Volatile Analysis of Roselle Extracts by SPME-GC-MS The extraction of volatile compounds from the matrix of the Roselle extracts was carried out by solid-phase microextraction (SPME). Twenty milliliters of Roselle extract were placed in a 40 mL amber headspace vial. Seven different spray drying temperatures were used. These were stored in containers with silica for future analysis. PA) exposed for 30 min at 60 °C in the headspace of the vial was then immediately inserted into the injection port of the gas chromatograph for 5 min at 240 °C [28]. To diminish some degradation effects of compounds and lost of volatile products is very common to use encapsulation agents [21. A magnetic stirrer was used for mixture homogenization. Bellefonte. The fresh calyces were washed for quick dipping over water distilled. Determination of Moisture in the Spray Dried Samples of Roselle In the samples of spray dried Roselle the percentage of moisture was measured by the method of the vacuum stove according to the AOAC-934. After the calyces were crushed manually and deposited in a closed container with 7 L of 30% methanol (v/v).06 [27]. Although the spray drying is a fast process. Materials and Methods Roselle Extracts Samples Fresh Roselle calyces (with 79% humidity) were collected from an experimental field in Michoacan. Quantitation was based in area percent corresponding to the identified components in the Total Ion Chromatogram (TIC). Volatile Compounds Identified in the Roselle Extract by SPME and GC-MS In the Roselle extract. Volatile compounds were identified by comparison of their retention indices tentatively only by mass spectra library Wiley 275L. This implies that the degradation problem in the samples of powder Roselle extracts were not gendered by the SPME analysis method. The adherence of powder to walls of the drying chamber is a commonly recognized effect in spray drying of solutions containing sugars and solids easy to agglomerate [30].000 rpm). there were terpene components. The peak areas identified by GC-MS were used as variables. These panelists were randomly selected based on availability.05). analysis of significant minimum difference (DMS) was made. It is observed that the pH of the powder does not change with different temperature treatment. Also. the variety of the Roselle is different. All the reconstituted samples were evaluated for sensorial acceptability by pairing a preference test.0 3.0 3. In general.44 80 3. Results & Discussion Spray Drying of Roselle Extracts The processing conditions for all the spray drying experiments were kept at the outlet temperature (80 °C) and the atomizer rate (26.48 74 3.48 74 4. The panel participating in the acceptance evaluation included 50 volunteers (50% females 18–45 years). The paired preference data were analyzed by binomial distribution [23]. Jalisco Campus. 20 volatile compounds were identified. only required an appropriate material of the fiber (DVB/Carboxen/PDMS) and a temperature of 60 °C.1 3. Roselle powder showed a noticeable tendency to stick to internal stainless steel surfaces of the drying chamber especially at higher inlet temperature because this temperature increase the feed flow rate [12]. which were randomly coded. Volatile Compounds of the Roselle Powder The Roselle powder was rehydrated to the same soluble solid concentration than the liquid extract to determine the volatile compounds. linalool and alphaTerpineol. Each panelist received the reconstituted sample in a random order. helium with a flow rate of 0.44 75 3. and a glass of water for rinsing and crackers for consumption between samples were supplied.48 . interest and regular consumption of Roselle drinks. In all experiments. This has two significant reasons: first. Sensorial Analysis All the powder samples were reconstituted at 12% of soluble solids and slightly sweetened with sugar. the name of current Roselle variety and the cited one should be mentioned [1. However. esters. injector port and detector temperatures were 220 and 260 °C. aldehydes and phenolic derivatives.0 3.0 3. In these samples 14 volatile com- Table 1 Weight (grams). was performed with the data obtained from GCMS.8 mL/min. Each panelist was served with 10 mL of chilled reconstituted samples and control in 30 mL clear plastic containers.48 74 4. 29]. 4. this indicates that each variety can have different compositions. The weight.0 3. among the Roselle powders to determine differences based on the pick area of each volatile component. In this paired preference test. moisture and pH of seven Roselle powder samples obtained by spray drying at different temperature are shown in Table 1. The second is that the isolation method of volatile compounds used in this work did not require boiling temperatures. 12]. panelists were asked to make a forced choice between the drinks [2. This test was used as a measurement of relative preference of one Roselle drink over another.44 78 4. moisture percentage and pH of the Roselle powder dried at different temperatures Treatment Spray drying temperature (°C) T1 150 T2 160 T3 170 T4 180 T5 190 T6 200 T7 210 Weight (g) Humidity (%) pH 73 5.0 3. This is probably due to the nature of the soluble solids. who were students and staff members of the Technological Institute of the West Mexico. All the samples were run at least in triplicates. The control was the original extract.64 Plant Foods Hum Nutr (2009) 64:62–67 for 5 min then ramped at 5 °C/min to 240 °C. Statistical Analysis An Analysis of Variance (ANOVA) using the Statistical Analysis System Software (SAS) and Duncan test at (p>0. The reconstituted samples were chilled at 5 °C for 24 h prior to sensory evaluation. These compounds were limonene. only the terpene compounds were similar to another works [6]. 87 b 0.50 0.33 0. cislinalool oxide.05).06 b 0. Only the compounds the alphaterpinolene. The eugenol is a compound resulting from degradation of the phenolic compounds as a consequence of the spray drying temperature of the Roselle samples.09 0.69 a 0.13 1.13 c 1.70 a Ethyl linoleate 0.18 a 0.20 b 0.00 ab 4. According to the analysis of the least significant difference (LSD) carried out among the Roselle powder samples. it is important to acknowledge that significant differences exist among the compounds identified in the liquid extract as the compounds identified in the Roselle powder. and decanal compounds were present in all experiments without significant difference. 2 is shown the upward behavior of the furfural.09 0.10 c 0.Plant Foods Hum Nutr (2009) 64:62–67 65 pounds were identified.44 a 0.19 b 1.30 d Phenolic derivatives Eugenol 0.06 b Volatile compounds generated by chemical degradation Sugar derivatives Furfural 0. and the eugenol.76 b Furanic linalool oxide Z and E 0.09 c 0.02 c 2.50 ab Different letters mean statistically significant difference using Duncan (p<0.80 0. the Roselle extract dehydrated at 190 °C presented the biggest concentration of volatile compounds and the least concentrations of degraded compounds that the other samples obtained from different spray drying temperatures. The Duncan’s test was based on the percentage area of the volatile compounds.69 c 3.13 a 0.67 a 0.10 c 0.51 ab 1. although there was a decrease in their concentration.07 b 0.31 b 0. The compounds generated by chemical degradation of the samples during the spray drying were the furfural.00 ab 0.10 ab ab a b ab ab a b ab ab a b a a a a ab b a ab b b a b 1.70 a 0.04 0.05 0.30 a 0.07 0.71 ab 0.16 a 0.35 a 0.85 b 0.10 0.40 b 1.18 a 0.15 b 0.50 b 0.69 a 1.35 b 0.13 c 1.45 b 0.29 b 0.05 0. derived of the degradation of sugar and fatty acids that were present in the liquid Roselle extract [6].28 a 4. In Fig. Duncan’s test (p<0.07 c Decanal 0.40 ab 0.10 c Aldehydes Benzaldehyde 0.20 4. Four different compounds were also generated. cis-linalool oxide. as shown in Table 2.68 a 0.40 a 0.80 b 4.08 0.20 c T160 160 °C T170 170 °C T180 180 °C T190 190 °C T200 200 °C T210 210 °C 0.25 0.06 b 0.05) determined that exist significant difference among the seven treatments realized to obtain Roselle powder at different spray drying temperatures. furanic linalool oxide Z and E and eugenol compounds due to the obtained the changes by the spray drying temperature.07 0. ethyl hexadecanoate.00 0.16 a 0. It was observed that the concentration of the furfural increased because the drying temperature propitiated its formation by degradation of sugars.87 a 0.10 ab Limonene 1. 1.72 a 0.53 b Ethyl linoleolate 0.12 1.17 a 0.05 c 0. In Table 2 the compounds of the Roselle powder are shown and the chromatograms are illustrated in Fig. The cis-linalool oxide and the furanic linalool oxide Z and E were the product of the chemical degradation of the fatty acids.06 0.60 0.07 ab 0.12 1.10 c 0.55 a 0. as shown in Table 2.14 1.68 a 0. In addition.16 a 0. This also was reported in drying Roselle calyces [6].28 a 1.09 c Fatty acid derivatives cis-Linalool oxide 0. furanic linalool oxide Z and E.10 b Esters Ethyl hexadecanoate 1. Ten of the 14 compounds identified are the same as the ones identified in the liquid extract.51 c 2. This result proved the hypothesis that the drying temperature had an effect on the retention of volatiles compounds.07 b 0.18 a Divers 4-Ethylguaiacol 0.70 ab Alpha-Terpinolene 0.55 a 0.11 c 1.00 0. This Table 2 Volatiles identified in the Roselle powder Spray drying temperature (°C) Area (%) T150 150 °C Volatile compounds retained in the powder Terpenoids p-Cymene 0.35 b 1.83 a 0.10 a Linalool 0. Multiple range tests with base in their retention .06 0.47 b 0. Figure 3 shows the percentage over the flavor preference among all the samples analyzed. Sensorial Analysis According to the sensorial analysis. The major components detected by chromatographic analysis played an important role. 1 Chromatogram of volatile constituents in Roselle powder dried at 190 °C. In comparison to the other treatments (different temperatures).5 3 2. where the highest acceptability was for the liquid extract followed by the T190 sample with statistically significant differences (p<0. T200=12%. more than 76% of the panelists showed that preference for the sample T190 than corresponded to 190 °C drying outlet temperature. and T210=12%. T170=52%. T160=40%.05). T180= 52%.5 0 150 160 170 180 190 200 210 Spray Drying Inlet Temperature (˚C) Furfural Cis-linalool oxide Furanic linalool oxide Z and E Eugenol Fig. since it contained the highest concentration of ten volatile com- 4 Area (%) 3. although the liquid extract has 92% of preference in the same conditions (T0). The time is in minutes indicates that it is difficult to obtain a powder exactly similar to the liquid extract of Roselle. this had the lowest percentage of 5 preference: T150=16%. Therefore. 3 Results of the paired preference tests of the Roselle reconstituted powder.5 90 0.5 2 100 1. Conclusions 4. 2 Effect of spray drying temperature on the concentration of degradation compounds present in Roselle powder Acceptance (%) 80 1 70 60 50 40 30 20 10 0 T0 T150 T160 T170 T180 T190 T200 T210 Treatments at different temperatures (ºC) Fig. it is clear than there is significant difference on acceptance among the Roselle powders and the original liquid extract according to the preference tests.5 The inlet air temperature of 190 °C used in the spray the drying of Roselle extract resulted in the best powder in terms of composition regarding the other treatments. T0 is Roselle liquid original extract .66 Plant Foods Hum Nutr (2009) 64:62–67 Fig. 1745-4506. Waliszewski SM.V. pp 1–22 26. F.1007/s11130-005-9023-x 8. Food Prod Develop 9:37–40 5. Chen SH. Talmon Y.) wines with varying calyx puree and total soluble solids: sensory acceptance. Hassan BH (1990) Spray drying of roselle (Hibiscus sabdariffa) extract. Jowitt R (1971) A study of some factors affecting the spray drying of concentrated orange juice.x 4. analysis. Mora R. Series 528. Brazil. techniques of analysis and sensory evaluation. Orta Z.Plant Foods Hum Nutr (2009) 64:62–67 pounds also showed in the original liquid extract.1016/ S0963-9969(01)00129-6 10. Brenner J (1983) The essence of spray-dried flavors. Badrie N (2006) Roselle/sorrel (Hibiscus sabdariffa L. Vennat B.2004. Soukup RJ (1993) Key flavors from heat reactions of food ingredients.). Chem Eng Prog 54:33–39 19. Food Technol 23:101–102 3. Remberg G. Re M. Angulo O. Woidich A. Kumar K. Flores H (2004) Optimization of spray drying of roselle extracts (Hibiscus sabdariffa L. quantitative descriptive and physicochemical analysis. Vernon-Carter EJ (1995) Studies on the interaction of arabic (Acacia senegal) and mesquite (Prosopis juliflora) gum as emulsion stabilizing agent. Jirovetz L. Kopelman IJ (1988) The microstructure of spray-dried microcapsules. References 1. Akindahunsi AA. Al-Kahtani AA. Messias LS. Zeng DD. Galíndez J. Nikiforov A (1992) Analysis of the volatiles in the seed oil of Hibiscus sabdariffa (Malvaceae) by means of GC-MS and GC-FTIR. USA 28. Spanier AM. Herrera J. Chen HH. Barradas DM.) sauces from enzymatic extracted calyces. Drying. Proceedings of the 14th International Drying Symposium. Miller JA (1993) Roles of proteins and peptides in meat flavor. 18th edn.1990.1111/j. Pouget MP. J Ethnopharmacol 89:161–164 doi:10.. Acknowledgement We thank their support in this investigation to the ITA-JAL. Camden B. Olaleye MT (2003) Toxicological investigation of aqueous-methanolic extract of the calyces of Hibiscus sabdariffa L. Molecular analysis and design. Perf Flav 40:886–888 15. Mouning P.) extract. Futura T (2000) Estimating retention of emulsified flavor in a single droplet during drying. Teranishi R (eds) Flavour science. D. Pedrero FDL. D’Heureux C. Sensible principles and techniques. volatile compounds. de C. J Food Process Preserv 29:228–245 11. This result was rehearsed for panelists in the preference test.1021/jf0207934 29. Souza L (1986) Meat flavor volatiles: a review of the composition. King CJ (1990) Spray drying food liquids and the retention of volatiles. American Chemical Society. Plant Foods Hum Nutr 60:153–159 doi:10. Food Serv Technol 4:141–148 doi:10. Greenwald CG (1984) Food quality factors in spray drying.1111/j. J Agric Food Chem 40:1186–1187 doi:10. Schettini H (2004) The influence of the liquid properties and the atomizing conditions on the physical characteristics of the spray-dried ferrous sulfate microparticles. Adv Dry 3:322–327 18. Dorantes L. Tsai P. In: Food flavor and safety. A: 597–604 14. Washington. J Sci Food Agric 88:116–124 25. choosing the T190 sample as the best after the original extract.1471-5740. Washington. Rubin L. American Chemical Society. Mujumdar AS (2004) A threedimensional simulation of a spray dryer with a rotary atomizer. J Foodserv 17:102–110 doi:10.x 13. Scarpellino R.). Andrade I. Tsai PJ (1998) Extraction.1111/ j.tb01601. Dry Technol 16:1195–1236 doi:10. and the peak area of the degraded compounds is smaller than other samples treated at higher temperature. Badrie N (2004) Consumer acceptance and physicochemical quality of processed red sorrel/roselle (Hibiscus sabdariffa L. King CJ. Food Res Int 35:351–356 doi:10. Trujillo PRL (2005) The consumption of Hibiscus sabdariffa dried calyx ethanolic extract reduced lipid profile in rats.00100. Carvajal O. DC 27. Huang TC. Huang L. Hayward PM. Kieckbush TG. Brazil. McIntosh J. Sammy GM (1975) Applications for roselle as red color food colorant. AOAC (1996) Official methods of analysis. Passos ML.) oil. J Agric Food Chem 51:2216–2221 doi:10.1016/S03788741(03)00276-9 9. Association of Official Analytical Chemists. Huang TCh (2005) Grey relational analysis of dried roselle (Hibiscus sabdariffa L. CoSNET and CIATEJ. Zhang ZM. Dry Technol 2(3):1125–1130 20.1080/ 07373939508916965 22. ACS Symp. Sao Paulo. Dry Technol 13:455–461 doi:10. Food Sci Nutr 24:141–243 30. Acree TE (1993) Bioassay in flavor research. Sanchez R. with an acceptability of 76%. Brennan JG. Tsai PJ. Beristain CI. Espinosa-González J. and study on the volatiles in roselle tea. DGETA. Proceedings of the 14th International Drying Symposium. Washington.x 2.1021/ jf00019a021 6. Pourrat A (1990) Identification of anthocyanins of Hibiscus sabdariffa. Su YM. México. Teranishi R (eds) Flavor science: sensible principles and techniques. This work suggests that the inlet air temperature of spray drying has a significant effect on the volatile compounds concentration of the Roselle liquid extract and therefore in its acceptance. Sao Paulo. In: Acree TE. and physical and chemical properties of avocado (Persea americana Mill. Ortiz MA. J Agric Food Chem 46:1101–1105 doi:10. Chen SH.A. Ré M (1998) Microencapsulation by spray drying. Jäger W. Chung Ch. 24. Pangborn RM (1989) Evaluación sensorial de los alimentos—Métodos analíticos.1365-2621. Pearce P. Li GK (2008) Study of the violatile composition of tomato during storage by a combination sampling method coupled with gas chromatography/mass spectrometry. A: 319–325 16. In: Acree TE. Nolasco C. DC 21.1021/jf970720y 7. DC. Ho CT. Drying Proceedings of the 14th International Drying Symposium. Infanzon RM. Guzmán RI (2003) Effect of different extraction methods on fatty acids.2006. J Food Technol 6:295 . 00028. J Food Sci 55:1073–1078 doi:10.1080/07373939808917460 23. B: 1174–1181 17. Sao Paulo. Esselen WB. Rosenberg M. Food Microstruct 7:15–23 67 12. on a laboratory scale. Brazil. Alhambra mexicana S. Drying. Jordan B (2004) Anthocyanin and antioxidant capacity in roselle (Hibiscus sabdariffa L. Shahidi F.