Abstract
The effect of hot air convective drying (HACD), microwave-vacuum drying (MWVD) and combined drying (HACD + MWVD) on the drying kinetics, bioactive compounds and color of blueberry pomace was evaluated. Drying time of blueberry pomace ranged from 0.6 to 6.7 h and moisture diffusion coefficients ranged from 7.94 × 10–8 to 1.83 × 10–7 m2/s. Drying caused degradation of total polyphenolics (TP) (39–76%), monomeric anthocyanins (21–77%) and antioxidant capacity values (24–76%). Drying time was shortened even by 91%, when MWVD was used instead of HACD. MWVD of blueberry pomace resulted in the smallest, while HACD at 60°C in the greatest loss of bioactive compounds and antioxidant capacity. HACD at 60°C + MWVD allowed to obtain a product with a higher content of TP, monomeric anthocyanins and a stronger antioxidant capacity than HACD at 90°C + MWVD. Combination of HACD at 60°C with MWVD allowed for the shortening of HACD time by 75% as well as for hapering the chemical changes as compared to HACD at 60°C. Even when the combination of HACD at 90°C with MWVD shortened the drying time by 68%, it did not improve the retention of TP, monomeric anthocyanins and antioxidant capacity when compared to HACD at 90°C.
Funding statement: The study was supported by National Science Centre (Poland) [2016/23/D/NZ9/02671]. This study was partially supported by the University of Warmia and Mazury in Olsztyn.
Conflict of interest: The authors declare that they have no conflict of interest.
References
[1] Brazelton C. World blueberry acreage and production report. Folsom: United States Highbush Blueberry Council - Industry Relations Committee, 2009.Search in Google Scholar
[2] Retamales JB, Hancock JF. Blueberries. Oxfordshire: CABI, 2012: 336. (Crop Production Science in Horticulture Series).10.1079/9781845939045.0000Search in Google Scholar
[3] FAO. Statistics Division, Food and Agriculture Organization of the United Nations. Production. Available at: http://faostat3.fao.org/home/E. Accessed: 10 Mar 2017.Search in Google Scholar
[4] Institution of Mechanical Engineers Global food. Waste not, Want not. Available at: http://www.imeche.org/docs/default-source/reports/Global_Food_Report.pdf?sfvrsn=0. Accessed: 10 Dec 2017Search in Google Scholar
[5] Michalska A, Łysiak G. Bioactive compounds of blueberries: post-harvest factors influencing the nutritional value of products. Int J Mol Sci. 2015;16(8):18642–63.10.3390/ijms160818642Search in Google Scholar PubMed
[6] Struck S, Plaza M, Turner C, Rohm H. Berry pomace – a review of processing and chemical analysis of its polyphenols. Int J Food Sci Technol. 2016;51:1305–18.10.1111/ijfs.13112Search in Google Scholar
[7] Rohm H, Brennan C, Turner C, Gunther E, Campbell G, Hernando I, et al. Adding value to fruit processing waste: innovative ways to incorporate fibers from berry pomace in baked and extruded cereal-based foods – a SUSFOOD project. Foods. 2015;4:690–97.10.3390/foods4040690Search in Google Scholar
[8] Kim H, Bartley GE, Rimando AM, Yokoyama W. Hepatic gene expression related to lower plasma cholesterol in hamsters fed high-fat diets supplemented with blueberry peels and peel extract. J Agric Food Chem. 2010;58:3984–91.10.1021/jf903230sSearch in Google Scholar PubMed
[9] You Q, Wang B, Chen F, Hunag Z, Wang X, Luo PG. Comparison of anthocyanins and phenolics in organically and conventionally grown blueberries in selected cultivars. Food Chem. 2011;125:201–08.10.1016/j.foodchem.2010.08.063Search in Google Scholar
[10] Lee J, Wrolstad RE. Extraction of anthocyanins and polyphenolics from blueberry processing waste. J Food Sci. 2004;69(7):564–73.10.1111/j.1365-2621.2004.tb13651.xSearch in Google Scholar
[11] Ratti C. Hot air and freeze-drying of high-valuable foods: a review. J Food Eng. 1999;49:311–19.10.1016/S0260-8774(00)00228-4Search in Google Scholar
[12] Zielinska M, Sadowski P, Błaszczak W. Freezing/thawing and microwave assisted drying of blueberries (Vaccinium corymbosum L.). LWT - Food Sci Technol. 2015;62(1,2):555–63.10.1016/j.lwt.2014.08.002Search in Google Scholar
[13] Zielinska M, Sadowski P, Błaszczak W. Combined hot air convective drying and microwave-vacuum drying of blueberries (Vaccinium corymbosum L.): drying kinetics and quality characteristics. Dry Technol. 2016;34(6):665–84.10.1080/07373937.2015.1070358Search in Google Scholar
[14] Zielinska M, Michalska A. Microwave-assisted drying of blueberry (Vaccinium corymbosum L.) fruits: drying kinetics, polyphenols, anthocyanins, antioxidant capacity, color and texture. Food Chem. 2016;221:671–80.10.1016/j.foodchem.2016.06.003Search in Google Scholar PubMed
[15] Kalt W, McDonald JE, Donner H. Anthocyanins, phenolics, and antioxidant capacity of processed low bush blueberry products. J Food Sci. 2000;65:390–93.10.1111/j.1365-2621.2000.tb16013.xSearch in Google Scholar
[16] Lohachoompol V, Srzednicki G, Craske J. The change of total anthocyanins in blueberries and their antioxidant effect after drying and freezing. J Biomed Biotechnol. 2004;5:248–52.10.1155/S1110724304406123Search in Google Scholar PubMed PubMed Central
[17] Mejia-Meza E, Yanez JA, Remsberg CM, Davies NM, Rasco B, Younce F, et al. Improving nutritional value of dried blueberries (Vaccinium corymbosum L.) combining microwave-vacuum, hot-air drying and freeze drying technologies. Int J Food Eng. 2008;4(5):10.10.1142/9789812771957_0117Search in Google Scholar
[18] Wojdyło A, Figiel A, Lech K, Nowicka P, Oszmiański J. Effect of convective and vacuum-microwave drying on the bioactive compounds, color, and antioxidant capacity of sour cherries. Food Bioprocess Technol. 2014;7(3):829–41.10.1007/s11947-013-1130-8Search in Google Scholar
[19] Woodroof JG, Luh BS, editors. Commercial Fruit Processing. Westport, CT: AVI Publishing Company, 1986.10.1007/978-94-011-7385-8Search in Google Scholar
[20] Cui ZW, Li CY, Song CF, Song Y. Combined microwave-vacuum and freeze drying of carrot and apple chips. Dry Technol. 2008;26(12):1517–23.10.1080/07373930802463960Search in Google Scholar
[21] Huang L, Zhang M, Wang L, Mujumdar AS, Sun D. Influence of combination drying methods on nutritional quality, texture, aroma and microstructure of apple slices. LWT - Food Sci Technol. 2012;47:183–88.10.1016/j.lwt.2011.12.009Search in Google Scholar
[22] Zielinska M, Zapotoczny P, Alves-Filho O, Eikevik TM, Błaszczak W. Microwave vacuum-assisted drying of green peas using heat pump and fluidized bed: a comparative study between atmospheric freeze drying and hot air convective drying. Dry Technol. 2013;31(6):633–42.10.1080/07373937.2012.751921Search in Google Scholar
[23] Crank J. The mathematics of diffusion. Oxford: Oxford University Press, 1975.Search in Google Scholar
[24] AOAC. Official methods of analysis. 12th ed. Washington, DC: AOAC, 1975.Search in Google Scholar
[25] Zheng W, Wang S. Oxygen radical absorbing capacity of phenolics in blueberries, cranberries, chokeberries, and lingonberries. J Agric Food Chem. 2003;51:502–09.10.1021/jf020728uSearch in Google Scholar PubMed
[26] Singleton VL, Rossi JA. Colorimetry of total phenolics with phosphomolybdic-phosphotungstic acid reagents. J Enol Vitic. 1965;16:144–58.10.5344/ajev.1965.16.3.144Search in Google Scholar
[27] Giusti MM, Wrolstad RE. Characterization and measurement of anthocyanins by UV–visible spectroscopy. In: Wrolstad RE, editor. Current protocols in food analytical chemistry. New York: Wiley, 2001.10.1002/0471142913.faf0102s00Search in Google Scholar
[28] Horszwald A, Andlauer W. Characterisation of bioactive compounds in berry juices by traditional photometric and modern microplate methods. J Berry Res. 2011;1:189–99.10.3233/JBR-2011-020Search in Google Scholar
[29] Hager TJ, Howard LR, Prior RL. Processing and storage effects on monomeric anthocyanins, percent polymeric color, and antioxidant capacity of processed blackberry products. J Agric Food Chem. 2008;56(3):689–95.10.1021/jf071994gSearch in Google Scholar PubMed
[30] Nsonzi F, Ramaswamy HS. Quality evaluation of osmo-convective dried blueberries. Dry Technol. 1998;16:705–23.10.1080/07373939808917431Search in Google Scholar
[31] Kumar N, Sarkar BC, Sharma HK. Mathematical modelling of thin layer hot air drying of carrot pomace. J Food Sci Technol. 2012;49(1):33–41.10.1007/s13197-011-0266-7Search in Google Scholar PubMed PubMed Central
[32] Sun J, Hu X, Zhao G, Wu J, Wang Z, Chen F. Characteristics of thin-layer infrared drying of apple pomace with and without hot air pre-drying. Food Sci Technol Int. 2007;13(2):91–97.10.1177/1082013207078525Search in Google Scholar
[33] Göğüş F, Maskan M. Air drying characteristics of solid waste (pomace) of olive oil processing. J Food Eng. 2006;72(4):378–82.10.1016/j.jfoodeng.2004.12.018Search in Google Scholar
[34] Castrejón ADR, Eichholz I, Rohn S, Kroh LW, Huyskenskeil S. Phenolic profile and antioxidant activity of highbush blueberry (Vaccinium corymbosum L.) during fruit maturation and ripening. Food Chem. 2008;109:564–72.10.1016/j.foodchem.2008.01.007Search in Google Scholar
[35] Dragovic-Uzelac V, Savic Z, Brala A, Levaj B, Bursac Kovacevic D, Bisko A. Evaluation of phenolic content and antioxidant capacity of blueberry cultivars (Vaccinium corymbosum L.) grown in the northwest Croatia. Food Technol and Biotech. 2010;48:214–21.Search in Google Scholar
[36] Casquete R, Castro SM, Villalobos MC, Serradilla MJ, Queiros RP, Saraiva JA, et al. High pressure extraction of polyphenolic compounds from citrus peels. High Press Res. 2014;34:447–51.10.1080/08957959.2014.986474Search in Google Scholar
[37] Michalska A, Wojdyło A, Lech K, Łysiak GP, Figiel A. Physicochemical properties of whole fruit plum powders obtained using different drying technologies. Food Chem. 2016;207:223–32.10.1016/j.foodchem.2016.03.075Search in Google Scholar PubMed
[38] Vaghri Z, Scaman CH, Kitts DD, Durance T, McArthur DA. Quality of the vacuum microwave dried blueberries in terms of color, composition, and antioxidant activity. 12th International Drying Symposium, paper 318 ed. Elsevier Science, Amsterdam, 2000: 1–10.Search in Google Scholar
[39] Samoticha J, Wojdyło A, Lech K. The influence of different the drying methods on chemical composition and antioxidant activity in chokeberries. LWT - Food Sci Technol. 2016;66:484–89.10.1016/j.lwt.2015.10.073Search in Google Scholar
[40] Borowska J, Zadernowski R, Markowski M, Białobrzewski I. The usage of less known fruit-bearing shrub in dried fruits production. (In Polish). Zesz Probl Post Nauk Roln. 1999;46:301–09.Search in Google Scholar
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