INVESTIGATION OF THE CHANGES IN THE REOLOGICAL PROPERTIES OF POMEGRANATE JUICE WITH OHMIC ASSISTED VACUUM EVAPORATION SYSTEM

Öz

In this study, the change in rheological properties of the pomegranate juice during evaporation process up to 40% TSS content by the ohmic assisted vacuum evaporation (OAVE) method applied at different voltage gradients (7.5, 10 and 12.5V/cm) was examined and compared by vacuum evaporation (VAE) method. It was determined that the best model characterizing the rheological behavior of pomegranate juice concentrates for all TSS contents investigated during the evaporation process was the Power Law Model. It was determined that µapparent and n values predicted with this model tend to increase as TSS content increased. It has been determined that pomegranate juice concentrates having high consistency coefficient can be obtained with OAVE process applied in high voltage gradients (10 and 12.5 V/cm). In addition, it was concluded that the OAVE process in low voltage gradient could be applied as alternative method for concentrate production with a consistency similar to VAE process.

Anahtar Kelimeler

• electrical
• consistency
• vacuum
• fruit juice
• dry matter

OHMİK DESTEKLİ VAKUM ALTINDA EVAPORASYON SİSTEMİ İLE KONSANTRE EDİLEN NAR SUYUNUN REOLOJİK ÖZELLİKLERİNDEKİ DEĞİŞİMİN İNCELENMESİ

Öz

Bu çalışmada, nar suyunun ohmik destekli vakum altında evaporasyon (OAVE) yöntemi ile farklı voltaj gradyanları (7.5, 10 ve 12.5 V/cm) uygulanarak %40 suda çözünür kuru madde (SÇKM) içeriğine kadar konsantre edilmesi sırasında reolojik özelliklerindeki değişim incelenmiş ve vakum altında evaporasyon (VAE) yöntemi ile karşılaştırılmıştır. Evaporasyon işlemi sırasında incelenen tüm SÇKM içeriklerinde nar suyu konsantrelerinin reolojik davranışını en iyi ifade eden modelin Üssel Model olduğu tespit edilmiştir. Bu model ile öngörülen görünür viskozite (µgörünür) ve akış davranış indeksleri (n) değerlerinin SÇKM içeriği arttıkça artma eğilimi gösterdiği belirlenmiştir. Yüksek voltaj gradyanlarında (10 ve 12.5 V/cm) uygulanan OAVE işlemi ile yüksek kıvam katsayısına sahip nar suyu konsantrelerinin elde edilebileceği tespit edilmiştir. Ek olarak, VAE işlemine benzer karakterde kıvama sahip konsantre eldesi için ise düşük voltaj gradyanında uygulanan OAVE işleminin alternatif olarak uygulanabilir olacağı sonucuna ulaşılmıştır.

Anahtar Kelimeler

• elektriksel
• kıvam
• vakum
• meyve suyu
• kuru madde

Kaynakça

1. Al-Maiman, S.A., Ahmad, S. (2002). Changes in physical and chemical properties during pomegranate (Punicagranatum L.) fruit maturation. Food Chemistry, 76(4), 437-441.
2. Altan, A., Maskan, M. (2005). Rheological behavior of pomegranate (Punicagranatum L.) juice and concentrate. Journal of Texture Studies, 36(1), 68-77.
3. Al-Said, F.A., Opara, L.U., Al-Yahyahi, R.A. (2009). Physico-chemical and textural quality attributes of pomegranate cultivars (Punicagranatum L.) grown in the Sultanate of Oman. Journal of Food Engineering, 90(1), 129-134.
4. Bozkir, H., Baysal, T. (2017). Concentration of apple juice using a vacuum microwave evaporator as a novel technique: Determination of quality characteristics. Journal of Food Process Engineering, 40(5), 1-9.
5. Bozkurt, H., Icier, F. (2009). Rheological characteristics of quince nectar during ohmic heating. International Journal of Food Properties, 12(4), 844-859.
6. Bozkurt, H., Icier, F. (2010a). Electrical conductivity changes of minced beef–fat blends during ohmic cooking. Journal of Food Engineering, 96(1), 86-92.
7. Bozkurt, H., Icier, F. (2010b). Ohmic cooking of ground beef: Effects on quality. Journal of Food Engineering, 96(4), 481-490.
8. Bozkurt, H., Icier, F. (2012). The change of apparent viscosity of liquid whole egg during ohmic and conventional heating. Journal of Food Process Engineering, 35(1), 120-133.

9. Cassano, A., Drioli, E., Galaverna, G., Marchelli, R., Di Silvestro, G., Cagnasso, P. (2003). Clarification and concentration of citrus and carrot juices by integrated membrane processes. Journal of Food Engineering, 57(2), 153-163.
10. Cemeroğlu, B. (2010). Gıda analizleri (2nd ed.). Gıda Teknolojisi Dernegi Yayınları. Ankara.
11. Cevik, M., Sabancı, S., İcier, F., Yıldız H. (2014). Changes on rheological properties of pomegranate (punicagranatum l. hicaznar) juices during concentration process. Bulgarian Chemical Communications, 46 (Special issue B), 87-91.
12. Cevik, M., Tezcan, D., Sabancı, S., İcier, F. (2016). Changes in rheological properties of koruk (unripe grape) juice concentrates during vacuum evaporation. Akademik Gıda, 14(4), 322-332.
13. Cevik, M., Icier, F. (2018). Effects of voltage gradient and fat content on changes of electrical conductivity of frozen minced beef meat during ohmic thawing. Journal of Food Process Engineering, 41(4), e12675.
14. Chin, N.L., Chan, S.M., Yusof, Y.A., Chuah, T.G., Talib, R.A. (2009). Modelling of rheological behaviour of pummelo juice concentrates using master-curve. Journal of Food Engineering, 93(2), 134-140.
15. Cho, W.Il., Yi, J.Y., Chung, M.S. (2016). Pasteurization of fermented red pepper paste by ohmic heating. Innovative Food Science and Emerging Technologies, 34, 180-186.
16. Cokgezme, O.F., Sabanci, S., Cevik, M., Yildiz, H., Icier, F. (2017). Performance analyses for evaporation of pomegranate juice in ohmic heating assisted vacuum system. Journal of Food Engineering, 207(4), 1–9.
17. Constenla, D.T., Lozano, J.E., Crapıste, G.H. (1989). Thermophysical properties of clarified apple juice as a function of concentration and temperature. Journal of Food Science, 54(3), 663–668.
18. Dak, M., Verma, R.C., Jaaffrey, S.N.A. (2007). Effect of temperature and concentration on rheological properties of ‘‘Kesar’’ mango juice. Journal of Food Engineering, 80(4), 1011-1015.
19. Darvishi, H., Mohammadia, P., Fadavi, A., Koushesh Saba, M., Behroozi-Khazaei, N. (2019). Quality preservation of orange concentrate by using hybrid ohmik-Vacuum Heating. Food Chemistry, 289, 292-298.
20. Fadavia, A., Yousefi, S., Darvishi, H., Mirsaeedghazi, H. (2018). Comparative study of ohmic vacuum, ohmic, and conventional-vacuum heating methods on the quality of tomato concentrate. Innovative Food Science and Emerging Technologies, 47, 225-230.
21. Gabsi, K, Trigui, M, Barrington, S, Helal, N.A., Taherian, A.R. (2013). Evaluation of rheological properties of date syrup. Journal of Food Engineering, 117, 165-172.
22. İçier, F. (2003). Gıdaların ohmik ısıtılmasının deneysel ve kuramsal olarak incelenmesi. Ege Üniversitesi Fen Bilimleri Enstitüsü Gıda Mühendisliği Anabilim Dalı Doktora Tezi, İzmir, Türkiye, 245s.
23. Icier, F., Tavman, S. (2007). Ohmic heating behaviour and rheological properties of ice cream mixes. International Journal of Food Properties, 9(4), 679-689.
24. Icier, F., Bozkurt, H. (2011). Ohmic heating of liquid whole egg: rheological behavior and fluid dynamics. Food and Bioprocess Technology, 4(7), 1253-1263.
25. Icier, F., Yildiz, H., Sabanci, S., Cevik, M., Cokgezme, O.F. (2017a). Ohmic heating assisted vacuum evaporation of pomegranate juice: Electrical conductivity changes. Innovative Food Science and Emerging Technologies, 39, 241-246.
26. Icier, F., Cokgezme, O.F., Sabanci, S. (2017b). Alternative thawing methods for the blanched/non‐blanched potato cubes: microwave, ohmic, and carbon fiber plate assisted cabin thawing. Journal of Food Process Engineering, 40(2), e12403.
27. Juszczak, L., Fortuna, T. (2004). Effect of temperature and soluble solids content on the viscosity of cherry juice concentrate. International Agrophysics, 18, 17-21.
28. Kaur, N., Singh, A.K. (2016). Ohmic Heating: Concept and Applications-A Review. Critical Reviews in Food Science and Nutrition, 56(14), 2338-2351.
29. Krokida, M.K., Maroulis, Z.B., Saravacos, G.D. (2001). Rheological properties of fluid fruit and vegetable puree products: Compilation of literature data. International Journal of Food Properties, 4(2), 179-200.
30. Maskan, M. (2006). Production of pomegranate (Punicagranatum L.) juice concentrates by various heating methods: colour degradation and kinetics. Journal of Food Engineering, 72(3), 218-224.
31. Morell, P., Fiszman, S.M., Varela, P., Hernando, I. (2014). Hydrocolloids for enhancing satiety: Relating oral digestion to rheology, structure and sensory perception. Food Hydrocolloids, 41, 343-353.
32. Onsekizoglu Bagci, P. (2015). Potential of membrane distillation for production of high quality fruit juice concentrate. Critical Reviews in Food Science and Nutrition, 55(8), 1098-1113.
33. Ozgen, M., Durgac, C., Serce, S., Kaya, C. (2008). Chemical and antioxidant properties of pomegranate cultivars grown in mediterranean region of Turkey. Food Chemistry, 111(3), 703-706.
34. Ozkan, N., Ho, I., Farid, M. (2004). Combined ohmic and plate heating of hamburger patties: quality of cooked patties. Journal of Food Engineering, 63(2), 141-145.
35. Quek, M.C., Chin, N.L., Yusof, Y.A. (2013). Modelling of rheological behaviour of soursop juice concentrates using shear rate–temperature–concentration superposition. Journal of Food Engineering, 118, 380-386.
36. Reznick, D. (1996). Ohmic heating of fluid foods. Food Technology, 250–251.
37. Sabanci, S., Icier, F. (2017). Applicability of ohmic heating assisted vacuum evaporation for concentration of sour cherry juice. Journal of Food Engineering, 212, 262-270.
38. Sabanci, S., Icier, F. (2019). Effects of Vacuum Ohmic Evaporation on Some Quality Properties of Sour Cherry Juice Concentrates. International Journal of Food Engineering, 15 (9), 20190055.
39. Sabanci, S., Cevik, M., Cokgezme, O.F., Yildiz, H., Icier, F. (2019). Quality characteristics of pomegranate juice concentrates produced by ohmic heating assisted vacuum evaporation. Journal of the Science of Food and Agriculture, 99 (5), 2589-2595.
40. Sastry, S.K., Salengke, S. (1998). Ohmic heating of solid–liquid mixtures: A comparison of mathematical models under worst-case heating conditions. Journal of Food Process Engineering, 21, 441-458.
41. Sensoy, I., Sastry, S.K. (2004). Ohmic blanching of mushrooms. Journal of Food Process Engineering, 27, 1-15.
42. Steffe, J.F. (1996). Rheological Methods in Food Process Engineering. 2nd Edition, Freeman Press, East Lansing.
43. Vardin, H., Fenercioğlu, H. (2003). Study on the development of pomegranate juice processing technology, Clarification of pomegranate juice. Nahrung/Food, 47(5), 300-303.
44. Yildiz, H., Bozkurt, H., Icier, F. (2009). Ohmic and conventional heating of pomegranate juice: effects on rheology, color, and total phenolics. Food Science and Technology International, 15(5), 503-512.