Kuru fasülye ve nohut diyet liflerinin kimyasal ve fizikokimyasal yapılarının incelenmesi
Evaluation of chemical and physicochemical properties of dietary fibers extracted from dry bean and chickpea
Yazar: DAMLA KAVASSAN
Danışman: PROF. DR. DİLEK BOYACIOĞLU
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / Gıda Mühendisliği Ana Bilim Dalı
Derece: Yüksek Lisans, 2017
Konu: Gıda Mühendisliği = Food Engineering

Özet:
Bakliyat ürünleri, yüksek oranda diyet lifi içeren gıdalardır. Dünyada ve Türkiyede yüksek miktarda üretimi olmasına rağmen diyet lifi içeriği açısından tüketiminin arttırılması ve insan sağlığı üzerine olumlu etkilerinden daha fazla yararlanılabilmesi için çalışmalar yapılmaktadır. Diyet lifinin insan sağlığı üzerine birçok olumlu etkisi olduğu kanıtlanmıştır. Ayrıca gıda endüstrisinde, fırıncılık üzünlerinde, içeceklerde, et ve et ürünlerinde gıda üretim prosesine katkı sağlayan, su bağlama kapasitesi, yağ bağlama kapasitesi ve şişme kapasitesi gibi fizikokimyasal özelliklerinden yararlanılmaktadır.
Bu çalışmada Türkiyede ve Dünyada en çok üretilen, aynı zamanda diyet lifi içeriğinin yüksek olduğu bilinen kuru fasülye ve nohuttan endüstriyel ölçekte üretim yapılabilecek bir metotla diyet lifi elde edilmesi ve bu diyet liflerinin kimyasal ve fizikokimyasal yapılarının incelenmesi amaçlanmıştır.
Diyet lifi ekstraksiyonu için yapılan önceki çalışmalarda kabuk ve kotiledonun biribirinden verimli bir şekilde ayrılamadığı tespit edilmiş ve kabuk ayırma için yapılan diğer çalışmalarda modifikasyon uygulanarak, verimli bir ayırım sağlanmıştır. Nohuttan %90,8 kotiledon, %9,2 kabuk; kuru fasülyeden ise %91,5 kotiledon, %8,5 kabuk elde edilmiştir.
Nohut ve fasülye kotiledon unlarından çözünür diyet lifi (ÇDL) ve çözünür olmayan diyet lifi (ÇODL) ekstraksiyonu yapılmıştır. Nohut ve kuru fasülyeden elde edilen kabuklar yüksek diyet lifi içeriklerinden dolayı ÇODL bileşeni olarak hesaplanmıştır. Nohuttan %16,6, kuru fasülyeden %13,7 toplam diyet lifi (TDL) bileşeni elde edilmiştir.
Elde edilen diyet liflerine, kotiledon unlarına ve kabuklara kompozisyon analizi olarak diyet lifi, protein, yağ, kül ve nem tayinleri uygulanmıştır. Bu analizler sonucunda fasülye ÇODL bileşeninin kompozisyonu; %6,5 nem, %3,4 yağ, %2,8 kül, %16,4 protein ve %70,9 karbonhidrat olarak, fasülye ÇDL bileşeninin kompozisyonu; %4,4 nem, %0,6 yağ, %4,9 kül, %22,7 protein ve % 67,4 karbonhidrat olarak, nohut ÇODL bileşeninin kompozisyonu; %6,2 nem, %2,6 yağ, %2,1 kül, %17,4 protein ve % 71,8 karbonhidrat olarak, nohut ÇDL bileşeninin kompozisyonu %7,3 nem, %0,4 yağ, %7,4 kül, %19,8 protein ve % 65,1 karbonhidrat olarak, nohut kotiledon ununun kompozisyonu; %19,2 nem, %4,1 yağ, %2,87 kül, %21 protein ve %52,8 karbonhidrat olarak, fasülye kotiledon ununun kompozisyonu; %21,3 nem, %2,5 yağ, %3,9 kül, %22,2 protein ve % 50,2 karbonhidrat olarak, nohut kabuk kompozisyonu; %10,6 nem, % 1,9 yağ, %3,2 kül, %7,5 protein ve %76,8 karbonhidrat olarak, fasülye kabuk kompozisyonu; %15,5 nem, %1,4 yağ, %2,9 kül, %2,9 protein ve % 77,3 karbonhidrat olarak, nohut kompozisyonu; %10,1 nem, %4,1 yağ, %2,9 kül, %21 protein ve %61,9 karbonhidrat olarak, kuru fasülyenin kompozisyonu; %11,1 nem, %2,5 yağ, %3,9 kül, %20,3 protein ve % 62,2 karbonhidrat olarak belirlenmiştir.
Elde edilen diyet lifi fraksiyonlarının %63-71,2 oranlarında diyet lifi, %17,4-22,7 oranları arasında protein içerdiği tespit edilmiştir. Elde edilen diyet lifi fraksiyonlarında proteinin tam olarak elimine edilememesinin sebebinin metot sırasında proteaz enziminin kullanılmaması olabileceği düşünülmektedir. Bu durumun isen gıda işleme prosesleri için bazı durumlarda protein içeriğini yükseltebilecek bir avantaj olarak kullanılabileceği düşünülmektedir.
Elde edilen diyet liflerinin fizikokimyasal yapılarının belirlenmesi için, su bağlama kapasitesi, yağ bağlama kapasitesi, emülsiyon oluşturma kapasitesi, şişme kapasitesi, yoğunluk ve birim yoğunluk analizleri yapılmıştır.
Bu analizler sonucunda en yüksek yağ bağlama kapasitesine, nohut kotiledondan elde edilen ÇODL'nin (8,4 g/g numune) sahip olduğu, fasülye kotiledondan elde edilen ÇODL'nin 8 g/g numune, nohuttan kotiledondan elde edilen ÇDL'nin 1,4 g/g numune, fasülye kotiledondan elde edilen ÇDL'nin ise 2,6 g/g numune yağ bağlama kapasitesine sahip olduğu belirlenmiştir.
Şişme kapasiteleri karşılaştırıldığında, nohut kotiledondan elde edilen ÇODL'nin 10 ml/g numune ile en yüksek kapasiteye sahip olduğu, fasülye kotiledondan elde edilen ÇODL'nin 4,3 ml/g numune, fasülye kotiledondan elde edilen ÇDL'nin 3,7 ml/g numune, nohut kotiledondan elde edilen ÇDL'nin 1,8 ml/g numune şişirme kapasitesine sahip olduğu belirlenmiştir.
Su tutma kapasitelerine bakıldığında ise sırasıyla nohut kotiledondan elde edilen ÇODL'nin 10,2 g/g numune, fasülye kotiledondan elde edilen ÇODL'nin 7 g/g numune, kuru fasülye kotiledondan elde edilen ÇDL'nin 1,1 g/g numune, nohut kotiledondan elde edilen ÇDL'nin 0,9 g/g numune su tutma kapasitesine sahip olduğu belirlenmiştir.
Emülsiyon oluşturma kapasiteleri fasülye ÇDL, nohut ÇDL, fasülye ÇODL ve nohut ÇODL için sırasıyla %39, %29, %17 ve %15 şekinde tespit edilmiştir. ÇDL bileşenlerinin emülsiyon oluşturma kapasitelerinin ÇODL bileşenlerinden daha yüksek olduğu belirlenmiştir.
İzole edilen diyet lifi bileşenlerinin yoğunlukları yapıln analiz sonucunda fasülye ÇDL için 0,52 g/ml, nohut ÇDL için 0,61 g/ml, fasülye ÇODL için 0,15 g/ml ve nohut ÇODL için 0,19 g/ml olarak belirlenmişitir. ÇDL bileşenlerinin yoğunluklarının ÇODL bileşenlerinden oldukça yüksek olduğu tespit edilmiştir.

Abstract:
Legume products such as dry bean, chickpea, peas and lentil have high level of dietary fibre and their dietary fibre fractions are potential functional food ingredients. Altough legume production level is very high in Turkey and the world, dietary fibre intake is not at adequate amount. Dietary fibre is one of the most valuable nutrient for human health because of the positive effects on gastrointestinal system, decreasing glisemic index, cardiovascular disease. There are a lot of studies which are proven the positive health effects of dietary fibre on human health.
Legumes contain high amount of dietary fibre in their structures. Dietary fibre is a healthy food additives which has positive effects on especially digestive system, cholesterol and blood sugar. Also, dry bean and chickpea are the most common legumes in Turkey and the most of other countries in the world.
Dietary fibres extracted from food legumes are used to improve viscosity, sensory analysis and shelf life of food products. There are a lot of studies about the addition of dietary fibre isolates to bakery products, beverages, chocolates, milk and milk products, meat and meat products, pastas and soups. Generally they add to bakery products because of the high water holding capacities. Thus, shelf life is extended and the economic product loss is reduced. They also used for increasing the viscosity and improve the stability in beverage products. To provide the homogenity, soluble dietary fibres such as pectin and inulin are used in beverage products.
Consequently, for all their positive effects on health, there is an increasing trend in product development to integrate legume's dietary fibres into foods such as baking products, dairy products, beverages and meat and meat products.
Moreover, physicochemical properties of legume's dietary fibres that are swelling capacity (SC), oil holding capacity (OHC), water holding capacity (WHC), density and emulsion capacity are very important properties for the food production processes. In the food industry, physicochemical properties are the advantages and very important parameters for the processes.
The aim of this study is extraction of the dietary fibre from dry bean and chickpea which are the most abundant varieties of legumes by a suitable methods for the usage in food industry and evaluation of that fibres according to chemical and physicochemical properties. Also investigate their purity, chamical composition and some physochemical properties.
Dry beans and chickpeas were obtained by Assocation of Agricultural Products, Grains Processing and Packaging Industries (PAKDER) in the scope of the project. Dietary fibre content was extracted and then chemical composition anlysis and some physicochemical analysis were applied to dietary fibre isolates and raw legumes. 
In the previous studies, hull and cotyledon could not seperated efficiently each other. Because of that, some modifications applied to existing methods and efficiency was increased. Seperated cotyledon and hull amounts are 90,8% cotyledon and 9,2% hull from chickpea and 91,5% cotyledon and 8,5% hull from dry bean.
Soluble dietary fiber and insoluble dietary fiber extraction is made from milled cotyledon flours of dry bean and chickpea. Hulls separated from cotyledon are estimated as insoluble dietary fiber because of their high amount of insoluble fibre content. Consequently, total dietary fiber isolate amount that includes soluble dietary fiber isolate of cotyledon, insoluble dietary fiber isolate of cotyledon and hull was calculated as 16,6% from chickpea and 13,7% from dry bean.
Chemical composition analysis such as protein, fat, ash and moisture are applied to extracted dietary fibre isolates, cotyledon flours, hulls and raw dry beans and chickpeas. According to that compositional analysis; composition of dry bean insoluble dietary fibre isolate is 6,5% moisture, 3,4% fat, 2,8% ash, 16,4% protein and 70,9 %carbonhydrate; composition of dry bean soluble dietary fiber isolate is 4,4% moisture, 0,6% fat, 4,9% ash, 22,7% protein and 67,4% carbonhydrate; composition of chickpea insoluble dietary fibre isolate is 6,2% moisture, 2,6% fat, 2,1% ash, 17,4% protein, 71,8% carbonhydrate; composition of chickpea soluble dietary fibre is 7,3% moisture, 0,4% fat, 7,4% ash, 19,8% protein and 65,1% carbonhydrate; composition of chickpea cotyledon flour is 19,2% moisture, 4,1% fat, 2,9% ash, 21% protein and 52,8% carbonhydrate, composition of dry bean cotyledon flour is 21,3% moisture, 2,5% fat, 3,9% ash, 22,2% protein and 50,2% carbonhydrate, composition of chickpea hull is 10,6% moisture, 1,9% fat, 3,2% ash, 7,5% protein and 76,8% carbonhydrate; composition of dry bean hull is 15,5% moisture, 1,4% fat, 2,9% ash, 2,9% protein and 77,3% carbonhydrate, composition of raw chickpea is 10,1% moisture, 4,1% fat, 2,9% ash, 21% protein and 61,9% carbonhydrate; composition of dry bean is 11,1% moisture, 2,5% fat, 3,9% ash, 20,3% protein and 62,2%carbonhydrate.
Additionally, sugar profile analysis was applied to dietary fibre isolates. According to results, glucose and sucrose are found to be predominant in soluble dietary fibres for both dry bean and chickpea isolate. Also, glucose was the predominant monomer for insoluble dietary fibre isolates extracted dry bean and chickpea.
Dietary fibre and protein analysis were made to both of extracted soluble dietary fibre isolates and insoluble dietary fibre isolates, cotyledon flours and separated hulls to determine the composition. According to results of the dietary fibre and protein analysis, dry bean insoluble dietary fibre isolates contain 69,6% dietary fibre and 16,4% protein; dry bean soluble dietary fibre isolates contain 67% dietary fibre and 22,7% protein; chickpea insoluble dietary fibre isolates include 71,2% dietary fibre and 17,4% protein and the chickpea soluble dietary fibres include 63% dietary fibre and 19,8% protein. Additionally, chickpea hulls have 76,6% dietary fibre and 7,5% protein contents, dry bean hulls have 73,9% dietary fibre and 2,9% protein content. This results indicate that protein could not eliminated entirely with this method because for the protein elimination, isoelectric protein precipitation method is applied and protease enzym is not used. Low amount of protein content in the extracted dietary fibre isolates might be an advantage for usage of the fibers in food industry as an alternative ingredient for food processes. Also the final product cost of the fibre isolates might be decreased with this method because only one enzyme is used at a little amount.
Moreover, physicochemical analysis which are swelling capacity, oil holding capacity, water holding capacity, density and emlsion forming capacity were applied to both soluble and insoluble dietary fibres.
According to results of the oil holding capacity analysis, insoluble dietary fibre extracted from chickpea cotyledon have the highest amount of oil holdinf capacity (8,4 g/g sample). It is determined that, insoluble dietary fiber extracted from dry bean cotyledon has 8 g/g sample and soluble fibre extracted from cotyledon of chickpea has 2,6 g/g sample oil holding capacity.
Legumes fibres are used in meat and meat products. According to the results of the oil holding capacity analysis, the insoluble dietary fibre isolates from both dry bean and chickpea can be used in meat products because of the high oil holding capacity
If the swelling capacities are compared, insoluble dietary fibre extracted from chickpea cotyledon is have the highest value as 10 ml/g sample. The swelling capacities of the insoluble dietary fibre extracted from dry bean cotyledon, the soluble dietary fibre extracted from dry bean cotyledon and the soluble fibre extracted from cihckpea cotyledon are 4,3 ml/g sample, 3,7 ml/g sample and 1,8 ml/g sample.
The water holding capacity of insoluble dietary fibre extracted from chickpea cotyledon have the highest value as 10,2 g/g sample, if it is compared to other dietary fibres. Insoluble dietary fibre extracted from dry bean cotyledon has 7 g/g sample, soluble dietary fibre extracted from dry bean cotyledon has 1,1 g/g sample and soluble dietary fibre extracted from chickpea has 0,9 g/g sample water holding capacity.
The water holding capacity is the indicator that is shown the usage of dietary fibre isolates as a functional ingredient. High water holding capacity results in increasing the viscosity and providing the modification of textural structure.
The swelling and water holding capacities of dietary fibre isolates are indications of their physiological role for gut function and controlling the glucose levels of blood.
Emulsion forming capacities of dry bean soluble dietary fibre isolate, chickpea soluble dietary fibre isolate, dry bean insoluble dietary fibre isolate, chickpea insoluble dietary fiber isolate were determined as 39%, 29%, 17%, 15%. This results show that emulsion capacities of soluble dietary fibre isolates are higher than insoluble dietary fibres isolates.
The densities of dietary fibre isolates are determined by direct density and bulk density analysis. According to results, the direct densities of dry bean soluble dietary fibre isolate and chickpea soluble isolate were found as 0,52 g/ml and 0,61 g/ml. 0,15 g/ml and 0,19 g/ml are the densities determined for dry bean insoluble dietary fibre isolate and chickpea dietary fibre isolate. The physiological structure is an indicator for the densities. Soluble dietary fibre isolates have an heavy and powder structure while the insoluble fibre isolates have piece by piece and light structure because of the density differences.
Within the scope of the extraction of the dietary fibres with high purity, applied isolation method for insoluble and soluble dietary fibres from dry bean and chickpea was achieved with highly purity. Howewer there are protein, ash, moisture and fat content at low amounts compared to dietary fibre contents in the isolates. Also isolation method has at least amount of enzyme usage because it is desired for the usage as food ingredients in the food industry with low cost.