با همکاری انجمن علوم و صنایع غذایی ایران

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه علوم و صنایع غذایی، دانشکده کشاورزی، دانشگاه صنعتی اصفهان، اصفهان، ایران.

چکیده

در این تحقیق برای اولین بار، عملکرد رس سپیولیت فعال‏شده با اسید در شفاف‏سازی آب‏سیب مورد بررسی قرار گرفت. از روش آماری سطح پاسخ جهت یافتن شرایط بهینه فرایند شفاف‏سازی استفاده شد و میزان کدورت آب‏سیب به‌عنوان پاسخ در نظر گرفته شد. سپس در شرایط بهینه، کارایی سپیولیت، بنتونیت و ترکیب این عوامل شفاف‏کننده با ژلاتین و کیزل‏ژل جهت شفاف‏سازی آب‏سیب مورد ارزیابی قرار گرفت. نتایج نشان داد که افزایش غلظت رس سپیولیت از 1/0 به 05/0 درصد وزنی/ حجمی، سبب افزایش کدورت آب‏سیب شد. در دو دمای 50 و 60 درجه سانتی‏گراد، بیشترین میزان کاهش کدورت مشاهده شد و با افزایش زمان فرایند تا 7 ساعت، میزان کدورت به‌صورت منحنی درجه دوم کاهش یافت. شرایط بهینه شفاف‏سازی، غلظت رس 05/0 درصد، دمای 50 درجه‏سانتی‏گراد و زمان 7 ساعت بدست آمد. نتایج نشان داد که دو تیمار ترکیب سپیولیت- ژلاتین-کیزل‎ژل و بنتونیت- ژلاتین- کیزل‎ژل فعال‏ترین عوامل شفاف‏کننده هستند و قادرند کدورت آب‏سیب را به میزان 7/99 درصد کاهش دهند. مطالعات کینتیکی نشان داد که سرعت تغییرات در کدورت، ویسکوزیته، میزان ترکیبات فنولیک کل و رنگ طی زمان شفاف‏سازی به ترتیب از مدل های کینتیکی درجه یک، صفر، یک و صفر تبعیت می‏کنند.

کلیدواژه‌ها

عنوان مقاله [English]

Application of Iranian Sepiolite in Clarification of Apple Juice: Changes on Quality Characteristics during Process

نویسندگان [English]

  • Marzieh Mirzaaghaei
  • Amir Hossein Goli
  • Milad Fathi

Department of Food Science and Technology, College of Agriculture, Isfahan University of Technology, Isfahan, Iran.

چکیده [English]

Introduction: Flavor, taste, odor and color of fresh apple juice is unstable during concentration process and storage. Pectic substances and phenolic compounds are responsible for these physicochemical changes. So, decreasing of these compounds is necessary to improve the appearance and marketability of apple juice. In fruit juice industry, clarification is one of the most important steps which removes pectin, polyphenols and other unfavorable components and prevents haze formation during storage. Enzymatic clarification (depectinization) can be applied for removal of pectic substances by using pectinase. This enzyme can hydrolyze pectin and produce pectin-protein complexes which would be settled easily. Also in depectinization step, some enzymes such as amylase and amyloglucosidase can be used to degrade starch. Fining agents such as gelatin, bentonite, activated carbon, silicasol or a combination of these compounds can be used in conventional clarification. Sepiolite is a natural fibrous phyllasillicate clay mineral with a formula Mg8Si12O30(OH)4(OH2)4. nH2O(n=6-8) which has specific physicochemical properties such as high porosity, surface area and adsorption capacity. This clay clay has been used in several important applications such as decolorization of sugar juice, removal of phosphorus from vegetable oil and enhancing decoloration of crude palm oil. In this research, efficiency of Sepiolite for apple juice clarification was evaluated. First, the response surface methodology (RSM) was used to optimize apple juice clarification conditions. Then, a comparison among Sepiolite and other commercial fining agents in respect to clarification efficiency was accomplished. Finally, three types of zero-, first- and second-order kinetic models were used for explanation of changes in turbidity, color, viscosity and total phenolic content (TPC) during clarification process of apple juice.

Materials and Methods: The pasteurized and unclarified apple juice, Bentonite, Gelatin (Bloom= 80-100), Amylase (Alphamyl MG) and Pectinase (Pectofruit XL) were gratefully obtained from Behnoosh Iran Co. (Shahrekord, Iran). Sepiolite (with specific surface area of 105 m2/g) was purchased from Farapooyan Isatis Yazd Co. (Yazd, Iran). The kieselgel and chemicals with analytical grade were purchased from Merck Co. (Germany). Sepiolite was activated with hydrochloric acid according to Balci’s method with slight modification. For evaluation of Sepiolite changes, some analysis like pH, acidity, density and the moisture content of Sepiolite clay were done before and after the activation by the method of Sabah and Çelik. Specific surface area was measured by using the BET method (Belsorp mini II, Japan). XRF method (PW148, Philips Co.) was used for determining of difference between Sepiolite elemental compositions before and after the activation. A pretreatment was conducted to improve the performance of fining agents according to Türkyilmaz et al.’s method with slight modification. The swelling capability of fining agents in water increases their clarification capacity. In the method of RSM, the independent factors at three levels were concentration of activated Sepiolite (0.05-0.1% w/v), temperature of clarification (50-60˚C) and process time (2-10 h). Juice turbidity was regarded as response. As the first step in clarification of apple juice, amylase and pectinase enzymes were applied (25 µl of each enzyme per 100 mL juice at 20˚C). The mixture was stirred and heated in an incubator at 55˚C for 1 h. Sepiolite was mixed with juice in certain concentrations, stirred and placed in definite temperature and time according to each run of RSM. Finally, the juice was centrifuged (12000 rpm for 5 min) to remove the clay from clarified juice. For kinetic studies, the above steps were done in the optimized conditions using 0.05% fining agents at 50˚C for 7 h. A portable turbidometer (MARTINI, Mi 415, Romania) and the capillary viscometer (Ubbelohde-Viscometer, Fisher, USA) were used for measuring the juice turbidity and viscosity at 20˚C and expressed as NTU (Nephelometeric Turbidity Unit) and centipoise (cp), respectively. Color was measured at 20˚C by using a color meter (ZE 6000, Nippon DENSHOKU). The parameters which used for color expression were L* and a* parameters based on CIE Lab system. The Folin-Ciocalteu reagent was used for measuring the total phenolic content of juice and expressed as mg gallic acid equivalent per 100 mL juice. To evaluate Sepiolite performance in juice clarification, following fining agents were applied at optimal conditions: sepiolite (S), commercial bentonite (B), and combination of these agents with gelatin (G) and kieselgel (K) (S+G, B+G, S+G+K, B+G+K). The used concentrations of bentonite, gelatin and kieselgel were 0.05%, 0.015% and 0.04% (w/v), respectively. Sampling was conducted at 1 h intervals to evaluate the changes in juice turbidity, viscosity, color and TPC during clarification process. The rates of changes were determined by three types of zero-, first- and second-order kinetic models.

Results and Discussion: Results showed that the activated Sepiolite had less amounts of weight loss, density and pH than the native sample. On the other hand, moisture content and acidity increased. Also, acid activated Sepiolite had higher amounts of SiO2 groups. The second-order polynomial (quadratic) model was suggested as the best for describing the optimum conditions of clarification with insignificant lack of fit and high R2 (0.9845). Based on the results, process time had a significant (p

کلیدواژه‌ها [English]

  • Activation
  • bentonite
  • Kinetic
  • Sepiolite
  • Specific area
Alan, N. and İşçi, S., 2014, Surface modification of sepiolite particles with polyurethane and polyvinyl alcohol. Progress in Organic Coatings, 77 (2), 444-448.
Arslanoğlu, F. N., Kar, F. and Arslan, N., 2005, Adsorption of dark coloured compounds from peach pulp by using granular activated carbon. Journal of food engineering, 68 (4), 409-417.
Bagci, P. O., 2014, Effective clarification of pomegranate juice: A comparative study of pretreatment methods and their influence on ultrafiltration flux. Journal of Food Engineering, 141, 58-64.
Balci, S., 1999, Effect of heating and acid pre-treatment on pore size distribution of sepiolite. Clay Minerals, 34 (4), 647-647.
Ceci, L. and Lozano, J., 1998, Determination of enzymatic activities of commercial pectinases for the clarification of apple juice. Food Chemistry, 61 (1), 237-241.
Chatterjee, S., Chatterjee, S., Chatterjee, B. P. and Guha, A. K., 2004, Clarification of fruit juice with chitosan. Process Biochemistry, 39 (12), 2229-2232.
Deshmukh, P. S., Manjunatha, S. and Raju, P., 2015, Rheological behaviour of enzyme clarified sapota (Achras sapota L) juice at different concentration and temperatures. Journal of food science and technology, 52 (4), 1896-1910.
Farmani, B., Haddade khodaparast, M.H., Hesari, J. and Rezaii Iraqi, E., 2006, Refining of raw sugarcane juice using bentonite: 2 - detemination of optimum quantity of gelatin, time and temperature of process with bentonite. Journal of food science and technology research, 2, 63-75.
Gao, L., Beveridge, T. and Reid, C., 1997, Effects of processing and packaging conditions on haze formation in apple juices. LWT-Food Science and Technology, 30 (1), 23-29.
Gökmen, V., Artık, N., Acar, J., Kahraman, N. and Poyrazoğlu, E., 2001, Effects of various clarification treatments on patulin, phenolic compound and organic acid compositions of apple juice. European Food Research and Technology, 213 (3), 194-199.
Gökmen, V. and Çetinkaya, Ö., 2007, Effect of pretreatment with gelatin and bentonite on permeate flux and fouling layer resistance during apple juice ultrafiltration. Journal of food engineering, 80 (1), 300-305.
Gökmen, V. and Serpen, A., 2002, Equilibrium and kinetic studies on the adsorption of dark colored compounds from apple juice using adsorbent resin. Journal of Food Engineering, 53 (3), 221-227.
Hernandez, E., Chen, C., Johnson, J. and Carter, R., 1995, Viscosity changes in orange juice after ultrafiltration and evaporation. Journal of Food Engineering, 25 (3), 387-396.
Jahed, E.; Khodaparast, M. H. H. and Khaneghah, A. M., 2014, Bentonite, temperature and pH effects on purification indexes of raw sugar beet juice to production of inverted liquid sugar. Applied Clay Science, 102, 155-163.
Kim, D. W., Kim, T. S., Jeong, Y. K. and Lee, J. K., 1992, Adsorption kinetics and behaviors of cellulase components on microcrystalline cellulose. Journal of Fermentation and Bioengineering, 73 (6), 461-466.
Koyuncu, H., Kul, A. R., Çalımlı, A., Yıldız, N. and Ceylan, H., 2007, Adsorption of dark compounds with bentonites in apple juice. LWT-Food Science and Technology, 40 (3), 489-497.
Lee, W., Yusof, S., Hamid, N. and Baharin, B. S., 2007, Effects of fining treatment and storage temperature on the quality of clarified banana juice. LWT-Food Science and Technology, 40 (10), 1755-1764.
Lee, W., Yusof, S., Hamid, N. S. A. and Baharin, B. S., 2006, Optimizing conditions for enzymatic clarification of banana juice using response surface methodology (RSM). Journal of food Engineering, 73 (1), 55-63.
Maskan, M., 2006, Production of pomegranate (Punica granatum L.) juice concentrate by various heating methods: colour degradation and kinetics. Journal of Food Engineering, 72 (3), 218-224.
Mirsaeedghazi, H., Emam-Djomeh, Z., Mousavi, S. M., Aroujalian, A. and Navidbakhsh, M., 2010, Clarification of pomegranate juice by microfiltration with PVDF membranes. Desalination, 264 (3), 243-248.
Miura, A., Nakazawa, K., Takei, T., Kumada, N., Kinomura, N., Ohki, R. and Koshiyama, H., 2012, Acid-, base-, and heat-induced degradation behavior of Chinese sepiolite. Ceramics International, 38 (6), 4677-4684.
Onsekizoglu, P., 2013, Production of high quality clarified pomegranate juice concentrate by membrane processes. Journal of Membrane Science, 442, 264-271.
Oszmiański, J. and Wojdyło, A., 2007, Effects of various clarification treatments on phenolic compounds and color of apple juice. European Food Research and Technology, 224 (6), 755-762.
Pinelo, M., Zeuner, B. and Meyer, A. S., 2010, Juice clarification by protease and pectinase treatments indicates new roles of pectin and protein in cherry juice turbidity. Food and bioproducts processing, 88 (2), 259-265.
Qiu, N., Guo, S. and Chang, Y., 2007, Study upon kinetic process of apple juice adsorption de-coloration by using adsorbent resin. Journal of food engineering, 81 (1), 243-249.
Rai, P., Majumdar, G., DasGupta, S. and De, S., 2005, Prediction of the viscosity of clarified fruit juice using artificial neural network: a combined effect of concentration and temperature. Journal of Food Engineering, 68 (4), 527-533.
Rinaldi, M., Caligiani, A., Borgese, R., Palla, G., Barbanti, D. and Massini, R., 2013, The effect of fruit processing and enzymatic treatments on pomegranate juice composition, antioxidant activity and polyphenols content. LWT-Food Science and Technology, 53 (1), 355-359.
Sabah, E. and Çelik, M. S., 2005, Sepiolite: An effective bleaching adsorbent for the physical refining of degummed rapeseed oil. Journal of the American Oil Chemists' Society, 82 (91), 911-916.
Sabah, E. and Majdan, M., 2009, Removal of phosphorus from vegetable oil by acid-activated sepiolite. Journal of Food Engineering, 91 (3), 423-427.
Sabah, E., Turan, M. and Celik, M., 2002, Adsorption mechanism of cationic surfactants onto acid-and heat-activated sepiolites. Water research, 36 (16), 3957-3964.
Suarez, M. and Garcia-Romero, E., 2012, Variability of the surface properties of sepiolite. Applied Clay Science, 67, 72-82.
Tajchakavit, S., Boye, J. and Couture, R., 2001, Effect of processing on post-bottling haze formation in apple juice. Food research international, 34 (5), 415-424.
Tastan, O. and Baysal, T., 2015, Clarification of pomegranate juice with chitosan: Changes on quality characteristics during storage. Food chemistry, 180, 211-218.
Tian, G., Wang, W., Kang, Y. and Wang, A., 2014, Study on thermal activated sepiolite for enhancing decoloration of crude palm oil. Journal of Thermal Analysis and Calorimetry, 117 (3), 1211-1219.
Turfan, Ö., Türkyilmaz, M., Yemİş, O. and Özkan, M., 2012, Effects of clarification and storage on anthocyanins and color of pomegranate juice concentrates. Journal of Food Quality, 35 (4), 272-282.
Türkyilmaz, M., Yemiş, O. and Özkan, M., 2012, Clarification and pasteurisation effects on monomeric anthocyanins and percent polymeric colour of black carrot (Daucus carota L.) juice. Food chemistry, 134 (2), 1052-1058.
Ünal, H. İ. and Erdoğan, B., 1998, The use of sepiolite for decolorization of sugar juice. Applied clay science, 12 (5), 419-429.
Vardin, H. and Fenercioǧlu, H., 2003, Study on the development of pomegranate juice processing technology: clarification of pomegranate juice. Food/Nahrung, 47 (5), 300-303.
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