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Aloe Vera Jel İçeceği ile Zenginleştilmiş Probiyotik Yoğurt Üretimi

Year 2021, Volume: 12 Issue: 2, 287 - 296, 01.12.2021
https://doi.org/10.29048/makufebed.941230

Abstract

Aloe vera (AV) süt, dondurma, şekerleme, sağlık içecekler gibi fonksiyonel gıdalarda kullanılmaktadır. Yapılan bu araştırmada, yoğurt kültürüne probiyotik ve teknolojik özelliklere sahip olan Lactobacillus plantarum AB6-25 suşu, %1, 2,5 ve 5 oranlarında AV jel içeceği ilave edilerek yoğurt üretimi yapılmıştır. Depolamanın 1, 7, 14 ve 21. günlerinde üretilen yoğurtların fizikokimyasal, mikrobiyolojik analizleri ve duyusal değerlendirilmesi yapılmıştır. Analiz sonuçlarına göre; 1.ve 21. günlerde pH değerleri 4,54-4,61 ve 4,34-4,45, yağ değerleri %2,90-3,0 ve %2,85-30, laktik asit cinsinden titrasyon asitliği %0,51-0,58 ve %1,07-1,51, kuru madde %11,32-11,93 ve %10,97-11,47, serum ayrılması %24,67-39,70 ve %29,60-39,11 arasında belirlenmiştir. Araştırma sonucunda tüm gruplar için en yüksek laktik asit bakteri sayımları 21. günde tespit edilmiştir. Duyusal özellik puanlarına bağlı olarak, AV ile üretilen yoğurtlarda 14 gün depolamanın uygun olduğu belirlenmiştir. Fizikokimyasal analiz sonuçları genel olarak değerlendirildiğinde probiyotik yoğurda AV jeli suyu ilavesi ile yoğurdun probiyotik bakteriler için taşıyıcı olarak kullanılabileceği ve %1 ile 5 arasında AV jeli suyu ilavesinin probiyotik yoğurt üretiminde başarıyla kullanılabileceği ortaya konmuştur.

Supporting Institution

TÜBİTAK

Project Number

2019 yılı TÜBİTAK 2209-B Sanayi Odaklı Lisans Bitirme Tezi Programı

Thanks

TÜBİTAK’a ve Yörükoğlu Süt ve Ürünleri San. Tic. A.Ş.’ye teşekkür ederiz.

References

  • Anonim. (2002). Çiğ süt Standardı, Türk Standartları Enstitüsü, Ankara.
  • Anonim. (2006). Yoğurt Standardı. TS 1330. Türk Standartlar Enstitüsü, Ankara.
  • Başyiğit, G., Kuleaşan, H., Karahan, A.G. (2006). Viability of human derived probiotic lactobacilli in ice-cream produced with sucrose and aspartame. Journal of Industrial Microbiology and Biotechnology, 33: 796-800.
  • Başyiğit, G., 2004. Bazı Laktik Asit Bakterilerinin Probiyotik Olarak Kullanılma Özellikleri. Yüksek Lisans Tezi, Süleyman Demirel Üniversitesi Fen Bilimleri Enstitüsü, 96 s, Isparta
  • Başyiğit Kılıç, G., Kuleaşan, H., Eralp, I., Karahan, A.G. (2009). Manufacture of Turkish Beyaz cheese added with probiotic strains. LWT - Food Science and Technology, 42: 1003-1008.
  • Başyiğit Kılıç, G., Karahan, A.G. (2010). Identification of lactic acid bacteria isolated from the fecal samples of healthy humans and patients with dyspepsia and determination of their pH, bile and antibiotic tolerance properties. Journal of Molecular Microbiology and Biotechnology, 18: 220-229.
  • Başyiğit Kılıç, G., Kuleaşan, H., Sömer, V.F., Akpınar, D. (2013). Determination of potential probiotic properties of human originated Lactobacillus plantarum strains. Biotechnology and Bioprocess Engineering, 18: 479-485.
  • Başyiğit Kılıç, G., Akpınar, D. (2013). The effects of different levels of β-glucan on yoghurt manufactured with Lactobacillus plantarum strains as adjunct culture. Journal of Food, Agriculture & Environment, 11(1): 281-287.
  • Başyiğit Kılıç, G., Akpınar, D. (2016). Assessment of technological characteristics of non-fat yoghurt manufactured with prebiotics and probiotic strains. Journal of Food Science and Technology, 53(1): 864-871.
  • Başyiğit Kılıç, G., Bilecen Şen, D., Alnakdalı, D., Gülşen, M. (2020). Aloe vera’nın gıda endüstrisinde kullanımı. Mühendislik Bilimleri ve Tasarım Dergisi/Journal of Engineering Sciences and Design, 8(1): 326-332.
  • Çelikel, A., Göncü, B., Akın, M.B., Akın, M.S. (2018). Süt ürünlerinde probiyotik bakterilerin canlılığını etkileyen faktörler. Batman Üniversitesi Yaşam Bilimleri Dergisi, 8(1/2): 59-68.
  • Çete, S., Arslan, F., Yaşar, A. (2005). Investigation of antimicrobial effects against some microorganisms of Aloe vera and Nerium oleander also examination of the effects on the xanthine oxidase activity in liver tissue treated with cyclosporin. Gazi University Journal of Science, 18(3): 375-380.
  • Deveci, H.A., Nur, G., Kırpık, M., Harmankaya, A., Yıldız, Y. (2016). Fenolik bileşik içeren bitkisel antioksidanlar. Kafkas Üniversitesi, Fen Bilimleri Enstitüsü Dergisi, 9(1): 26-32.
  • El-Sayed, S.M., El-Sayed, H.S. (2020). Production of UF-soft cheese using probiotic bacteria and Aloe vera pulp as a good source of nutrients. Annals of Agricultural Sciences, 65(1): 13-20.
  • Halkman, A.K. (2005). Gıda Mikrobiyolojisi Uygulamaları, Merck, Ankara.
  • Hamman, J.H. (2008). Composition and applications of Aloe vera leaf gel. Molecules, 13(8): 1599-1616.
  • Hussain, S.A., Patil, G.R., Yadav, V., Singh, R.R.B. (2015). Effect of storage on sensory quality, pH, wheying-off and probiotic count of lassi supplemented with Aloe barbadensis Miller juice. Indian Journal of Dairy Science, 68(2): 105.
  • Ikram, A., Qasim Raza, S., Saeed, F., Afzaal, M., Munir, H., Ahmed, A.,Zahid, M., Muhammad Anjum, F. (2021). Effect of adding Aloe vera jell on the quality and sensory properties of yogurt. Food Science & Nutrition, 9(1): 480-488.
  • Işıdan, H. (2009). Probiyotikler. Aquaculture Studies, 9(1): 009-010.
  • Javed, S. (2014). Aloe vera gel in food, health products, and cosmetics industry. In Studies in Natural Products Chemistry, 41: 261-285.
  • Karami, M. (2018). The effect of zinc and vitamin B12 together with thyme and Aloe vera extracts on the viability of Lactobacillus acidophilus LA‐5® and physicochemical properties of Iranian yoghurt drink (Doogh). International Journal of Dairy Technology, 71: 149-156.
  • Karami, M.,Khodakarami, M. (2019). Evaluation of the effects of Aloe vera extract on chemical and microbial properties of low fat stirred probiotic yoghurt. Food Science and Technology, 16(94): 127-138.
  • Kaur, S., Kaur, H.P., Gupta, P. (2015). Physico-chemical analysis of Aloe vera fortified probiotic yoghurt. Internatıonal Journal of Advances ın Pharmacy, Biology and Chemistry, 4(2): 501-508.
  • Karahan, A.G., Arıdoğan-Cicioğlu, B., Çakmakçı, M.L. (2002). Genel Mikrobiyoloji Uygulama Kılavuzu. SDÜ Yayın No. 24: 171s.
  • Kaya, H.İ. (2013). Tarhana izolatı bazı laktik asit bakterilerinin bakteriyosinleri ve fermantasyonda patojen bakteriler üzerine etkisi. Master Tezi, Pamukkale Üniversitesi, Fen Bilimleri Enstitüsü, Denizli, Türkiye.
  • Keogh, M.K., O’Kennedy, B.T. (199)8. Rheology of stirred yogurt as affected by added milk fat, protein and hydrocolloids. Journal of Food Science, 63(1): 108-112.
  • Mahmoudi, R., Bajalanlou, F., Ghajarbeygi, P., Pakbin, B. (2016). Chemical properties and sensory evaluation of probiotic yoghurt manufactured with aqueous extract of Aloe vera. Journal of Biology and Today's World, 5(11): 197-202.
  • Mendoza Mencia, J.M. (2018). Functional Plain Yogurt Enhanced with Inulin and Aloe Vera. Master of Science, School of Animal Sciences, Louisiana State University and Agricultural and Mechanical College.
  • Mokoena, M.P. (2017). Lactic acid bacteria and their bacteriocins: Classification, biosynthesis and applications against uropathogens: A mini-review. Molecules, 22(8): 1255.
  • Muhtekar, A., Desale, R.J., Bhosale, S. (2018). Effect of sensory and microbial properties of yogurt fortified with Aloe vera. The Pharma Innovation Journal, 7(10):146-14.
  • Niko, N., Ghajarbeygi, P., Mahmoudi, R., Mousavi, S., Mardani, K. (2016). Inhibitory effects of Aloe vera gel aqueous extract and L. casei against E. coli in yoghurt. Journal of Biology and Today's World, 5(9): 157-162.
  • Oğan, Y., Sezgin Ceyhun, E. (2019). Katkı maddesi antioksidanların gastronomi açısından değerlendirilmesi. Artvin International Congress on Social Sciences (AICOSS 19), 17-19.
  • Omak, G., Özcan, T., & Ersan, L. Y. (2016). Biyolojik Detoksifikasyon ve Probiyotikler. Uludağ Üniversitesi Ziraat Fakültesi Dergisi, 30(1): 157-168.
  • Özçelik, S., 1998. Gıda Mikrobiyolojisi Uygulama Kılavuzu. Süleyman Demirel Üniversitesi Ziraat Fakültesi Yayın No:7, Ders Kitapları No:7, Isparta.
  • Panesar,P.S., Shinde , C. (2012). Effect of storage on syneresis, pH, Lactobacillus acidophilus count, Bifidobacterium bifidum count of Aloe vera fortified probiotic yoghurt. Current Research in Dairy Sciences, 4(1): 17-23.
  • Surjushe, A., Vasani, R., Saple, D.G. (2008). Aloe vera: a short review. Indian Journal of Dermatology, 53(4): 163.
  • Tekin, F., Şahin, O.Z., Karasu, Z., Nart, D., Özütemiz, Ö., Ersöz, G., Batur,Y., İlter, T. (2006). Aloe veraya bağlı ciddi toksik hepatit: Olgu sunumu. Akademik Gastroenteroloji Dergisi, 5(2): 134-136. Todorov, S.D., Stojanovski, S., Iliev, I., Moncheva, P., Nero, L.A., Ivanova, I.V. (2017). Technology and safety assessment for lactic acid bacteria isolated from traditional bulgarian fermented meat product “lukanka”. Brazilian Journal of Microbiology, 48(3): 576-586.
  • Uymaz, B. (2010). Probiyotikler ve kullanım alanları. Pamukkale Üniversitesi Mühendislik Bilimleri Dergisi, 16(1): 95-104.
  • Üçüncü, M. (2005). Süt ve Mamülleri Teknolojisi. Meta Basım, İzmir. 434-435.
  • Xiong, T., Guan, Q., Song, S., Hao, M., Xie, M. (2012). Dynamic changes of lactic acid bacteria flora during chinese sauerkraut fermentation. Food Control, 26(1): 178-181.
  • Yadav, A.K., Singh, A., Yadav, K.C. (2018). Efficacy of flavored Aloe vera cubes in probiotic yoğurt. Journal of Pharmacognosy and Phytochemistry, 7(4): 1609-1614.
  • Yeganehzad, S., Mzaheri-Tehrani, M., Shahidi, F. (2007). Studying microbial, physiochemical and sensory properties of directly concentrated probiotic yoghurt. African Journal of Agricultural Research, 2(8), 366-369.
  • Yılmaz, L. (2006). Yoğurt benzeri fermente süt ürünleri üretiminde farklı probiyotik kültür kombinasyonlarının kullanımı, Doktora Tezi, Uludağ Üniversitesi, Fen Bilimleri Enstitüsü, Bursa, Türkiye.

Production of Probiotic Yogurt Enriched with Aloe Vera Gel Drink

Year 2021, Volume: 12 Issue: 2, 287 - 296, 01.12.2021
https://doi.org/10.29048/makufebed.941230

Abstract

Aloe vera (AV) is used in functional food products including milk, ice cream, confectionery and health drinks. In this study, yogurt was produced by addition of Lactobacillus plantarum AB6-25 strain which has probiotic and technological properties, and AV gel drink at the rates of 1, 2.5 and 5%. Physicochemical, microbiological analysis and sensory evaluation of yoghurts were performed produced on the 1st, 7th, 14th and 21st days of storage. Results indicated that pH, fat, titratable acidity, dry matter and syneresis were determined as 4.54-4.61 and, 2.90-3.0% and 0.51-0.58% and 11.32-11.93% and, 24.67-39.70% and 29.60-39.11% on day 1 and 4.34-4.45, 2.85-3.0%, 1.07-1.51%, 10.97-11.47, 24.67-39.70 and 29.60-39.11 on day 21, respectively. As a result of the research, the highest lactic acid bacteria counts for all groups were detected after 21 days of storage. Sensory analysis results revealed that 14 days of storage was the most appropriate storage period for yoghurts produced with AV. Results of the physicochemical analysis, revealed that the addition of AV gel water in probiotic yoghurt could be used as a carrier for probiotic bacteria and the addition of AV gel water between 1 and 5% could be used successfully in the production of probiotic yoghurt.

Project Number

2019 yılı TÜBİTAK 2209-B Sanayi Odaklı Lisans Bitirme Tezi Programı

References

  • Anonim. (2002). Çiğ süt Standardı, Türk Standartları Enstitüsü, Ankara.
  • Anonim. (2006). Yoğurt Standardı. TS 1330. Türk Standartlar Enstitüsü, Ankara.
  • Başyiğit, G., Kuleaşan, H., Karahan, A.G. (2006). Viability of human derived probiotic lactobacilli in ice-cream produced with sucrose and aspartame. Journal of Industrial Microbiology and Biotechnology, 33: 796-800.
  • Başyiğit, G., 2004. Bazı Laktik Asit Bakterilerinin Probiyotik Olarak Kullanılma Özellikleri. Yüksek Lisans Tezi, Süleyman Demirel Üniversitesi Fen Bilimleri Enstitüsü, 96 s, Isparta
  • Başyiğit Kılıç, G., Kuleaşan, H., Eralp, I., Karahan, A.G. (2009). Manufacture of Turkish Beyaz cheese added with probiotic strains. LWT - Food Science and Technology, 42: 1003-1008.
  • Başyiğit Kılıç, G., Karahan, A.G. (2010). Identification of lactic acid bacteria isolated from the fecal samples of healthy humans and patients with dyspepsia and determination of their pH, bile and antibiotic tolerance properties. Journal of Molecular Microbiology and Biotechnology, 18: 220-229.
  • Başyiğit Kılıç, G., Kuleaşan, H., Sömer, V.F., Akpınar, D. (2013). Determination of potential probiotic properties of human originated Lactobacillus plantarum strains. Biotechnology and Bioprocess Engineering, 18: 479-485.
  • Başyiğit Kılıç, G., Akpınar, D. (2013). The effects of different levels of β-glucan on yoghurt manufactured with Lactobacillus plantarum strains as adjunct culture. Journal of Food, Agriculture & Environment, 11(1): 281-287.
  • Başyiğit Kılıç, G., Akpınar, D. (2016). Assessment of technological characteristics of non-fat yoghurt manufactured with prebiotics and probiotic strains. Journal of Food Science and Technology, 53(1): 864-871.
  • Başyiğit Kılıç, G., Bilecen Şen, D., Alnakdalı, D., Gülşen, M. (2020). Aloe vera’nın gıda endüstrisinde kullanımı. Mühendislik Bilimleri ve Tasarım Dergisi/Journal of Engineering Sciences and Design, 8(1): 326-332.
  • Çelikel, A., Göncü, B., Akın, M.B., Akın, M.S. (2018). Süt ürünlerinde probiyotik bakterilerin canlılığını etkileyen faktörler. Batman Üniversitesi Yaşam Bilimleri Dergisi, 8(1/2): 59-68.
  • Çete, S., Arslan, F., Yaşar, A. (2005). Investigation of antimicrobial effects against some microorganisms of Aloe vera and Nerium oleander also examination of the effects on the xanthine oxidase activity in liver tissue treated with cyclosporin. Gazi University Journal of Science, 18(3): 375-380.
  • Deveci, H.A., Nur, G., Kırpık, M., Harmankaya, A., Yıldız, Y. (2016). Fenolik bileşik içeren bitkisel antioksidanlar. Kafkas Üniversitesi, Fen Bilimleri Enstitüsü Dergisi, 9(1): 26-32.
  • El-Sayed, S.M., El-Sayed, H.S. (2020). Production of UF-soft cheese using probiotic bacteria and Aloe vera pulp as a good source of nutrients. Annals of Agricultural Sciences, 65(1): 13-20.
  • Halkman, A.K. (2005). Gıda Mikrobiyolojisi Uygulamaları, Merck, Ankara.
  • Hamman, J.H. (2008). Composition and applications of Aloe vera leaf gel. Molecules, 13(8): 1599-1616.
  • Hussain, S.A., Patil, G.R., Yadav, V., Singh, R.R.B. (2015). Effect of storage on sensory quality, pH, wheying-off and probiotic count of lassi supplemented with Aloe barbadensis Miller juice. Indian Journal of Dairy Science, 68(2): 105.
  • Ikram, A., Qasim Raza, S., Saeed, F., Afzaal, M., Munir, H., Ahmed, A.,Zahid, M., Muhammad Anjum, F. (2021). Effect of adding Aloe vera jell on the quality and sensory properties of yogurt. Food Science & Nutrition, 9(1): 480-488.
  • Işıdan, H. (2009). Probiyotikler. Aquaculture Studies, 9(1): 009-010.
  • Javed, S. (2014). Aloe vera gel in food, health products, and cosmetics industry. In Studies in Natural Products Chemistry, 41: 261-285.
  • Karami, M. (2018). The effect of zinc and vitamin B12 together with thyme and Aloe vera extracts on the viability of Lactobacillus acidophilus LA‐5® and physicochemical properties of Iranian yoghurt drink (Doogh). International Journal of Dairy Technology, 71: 149-156.
  • Karami, M.,Khodakarami, M. (2019). Evaluation of the effects of Aloe vera extract on chemical and microbial properties of low fat stirred probiotic yoghurt. Food Science and Technology, 16(94): 127-138.
  • Kaur, S., Kaur, H.P., Gupta, P. (2015). Physico-chemical analysis of Aloe vera fortified probiotic yoghurt. Internatıonal Journal of Advances ın Pharmacy, Biology and Chemistry, 4(2): 501-508.
  • Karahan, A.G., Arıdoğan-Cicioğlu, B., Çakmakçı, M.L. (2002). Genel Mikrobiyoloji Uygulama Kılavuzu. SDÜ Yayın No. 24: 171s.
  • Kaya, H.İ. (2013). Tarhana izolatı bazı laktik asit bakterilerinin bakteriyosinleri ve fermantasyonda patojen bakteriler üzerine etkisi. Master Tezi, Pamukkale Üniversitesi, Fen Bilimleri Enstitüsü, Denizli, Türkiye.
  • Keogh, M.K., O’Kennedy, B.T. (199)8. Rheology of stirred yogurt as affected by added milk fat, protein and hydrocolloids. Journal of Food Science, 63(1): 108-112.
  • Mahmoudi, R., Bajalanlou, F., Ghajarbeygi, P., Pakbin, B. (2016). Chemical properties and sensory evaluation of probiotic yoghurt manufactured with aqueous extract of Aloe vera. Journal of Biology and Today's World, 5(11): 197-202.
  • Mendoza Mencia, J.M. (2018). Functional Plain Yogurt Enhanced with Inulin and Aloe Vera. Master of Science, School of Animal Sciences, Louisiana State University and Agricultural and Mechanical College.
  • Mokoena, M.P. (2017). Lactic acid bacteria and their bacteriocins: Classification, biosynthesis and applications against uropathogens: A mini-review. Molecules, 22(8): 1255.
  • Muhtekar, A., Desale, R.J., Bhosale, S. (2018). Effect of sensory and microbial properties of yogurt fortified with Aloe vera. The Pharma Innovation Journal, 7(10):146-14.
  • Niko, N., Ghajarbeygi, P., Mahmoudi, R., Mousavi, S., Mardani, K. (2016). Inhibitory effects of Aloe vera gel aqueous extract and L. casei against E. coli in yoghurt. Journal of Biology and Today's World, 5(9): 157-162.
  • Oğan, Y., Sezgin Ceyhun, E. (2019). Katkı maddesi antioksidanların gastronomi açısından değerlendirilmesi. Artvin International Congress on Social Sciences (AICOSS 19), 17-19.
  • Omak, G., Özcan, T., & Ersan, L. Y. (2016). Biyolojik Detoksifikasyon ve Probiyotikler. Uludağ Üniversitesi Ziraat Fakültesi Dergisi, 30(1): 157-168.
  • Özçelik, S., 1998. Gıda Mikrobiyolojisi Uygulama Kılavuzu. Süleyman Demirel Üniversitesi Ziraat Fakültesi Yayın No:7, Ders Kitapları No:7, Isparta.
  • Panesar,P.S., Shinde , C. (2012). Effect of storage on syneresis, pH, Lactobacillus acidophilus count, Bifidobacterium bifidum count of Aloe vera fortified probiotic yoghurt. Current Research in Dairy Sciences, 4(1): 17-23.
  • Surjushe, A., Vasani, R., Saple, D.G. (2008). Aloe vera: a short review. Indian Journal of Dermatology, 53(4): 163.
  • Tekin, F., Şahin, O.Z., Karasu, Z., Nart, D., Özütemiz, Ö., Ersöz, G., Batur,Y., İlter, T. (2006). Aloe veraya bağlı ciddi toksik hepatit: Olgu sunumu. Akademik Gastroenteroloji Dergisi, 5(2): 134-136. Todorov, S.D., Stojanovski, S., Iliev, I., Moncheva, P., Nero, L.A., Ivanova, I.V. (2017). Technology and safety assessment for lactic acid bacteria isolated from traditional bulgarian fermented meat product “lukanka”. Brazilian Journal of Microbiology, 48(3): 576-586.
  • Uymaz, B. (2010). Probiyotikler ve kullanım alanları. Pamukkale Üniversitesi Mühendislik Bilimleri Dergisi, 16(1): 95-104.
  • Üçüncü, M. (2005). Süt ve Mamülleri Teknolojisi. Meta Basım, İzmir. 434-435.
  • Xiong, T., Guan, Q., Song, S., Hao, M., Xie, M. (2012). Dynamic changes of lactic acid bacteria flora during chinese sauerkraut fermentation. Food Control, 26(1): 178-181.
  • Yadav, A.K., Singh, A., Yadav, K.C. (2018). Efficacy of flavored Aloe vera cubes in probiotic yoğurt. Journal of Pharmacognosy and Phytochemistry, 7(4): 1609-1614.
  • Yeganehzad, S., Mzaheri-Tehrani, M., Shahidi, F. (2007). Studying microbial, physiochemical and sensory properties of directly concentrated probiotic yoghurt. African Journal of Agricultural Research, 2(8), 366-369.
  • Yılmaz, L. (2006). Yoğurt benzeri fermente süt ürünleri üretiminde farklı probiyotik kültür kombinasyonlarının kullanımı, Doktora Tezi, Uludağ Üniversitesi, Fen Bilimleri Enstitüsü, Bursa, Türkiye.
There are 43 citations in total.

Details

Primary Language Turkish
Subjects Engineering
Journal Section Research Paper
Authors

Cansu Söküt 0000-0003-4483-9097

Gülden Başyiğit Kılıç 0000-0003-1211-0568

Sultan Barın 0000-0001-8715-2397

Aslı Albayrak This is me 0000-0002-1636-148X

Project Number 2019 yılı TÜBİTAK 2209-B Sanayi Odaklı Lisans Bitirme Tezi Programı
Publication Date December 1, 2021
Acceptance Date June 28, 2021
Published in Issue Year 2021 Volume: 12 Issue: 2

Cite

APA Söküt, C., Başyiğit Kılıç, G., Barın, S., Albayrak, A. (2021). Aloe Vera Jel İçeceği ile Zenginleştilmiş Probiyotik Yoğurt Üretimi. Mehmet Akif Ersoy Üniversitesi Fen Bilimleri Enstitüsü Dergisi, 12(2), 287-296. https://doi.org/10.29048/makufebed.941230