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Tez Y ksek Lisans -- stanbul Teknik niversitesi Fen Bilimleri Enstit s 2014 Thesis M Sc -- stanbul Technical University Institute of Science and Technology 2014 Nar meyvesi i erdi i bile enlerle insan beslenmesinde nemli yeri olan fonksiyonel bir g dad r Fenolik bile enler ve polifenoller antioksidan aktiviteleri nedeniyle nemli antimutajenik ve antikanserojenik zelliklere sahip olup kalp ve damar hastal klar na kar da koruyucu etkilere sahiptir Nar n bu nemli bile enleri ve bile enlerinin y ksek antioksidan aktivitesi nar nar r nleri ve nardan elde edilen meyve sular na olan ilgiyi son y llarda artt rm t r Dondurarak muhafaza meyvelerin aroma ve besinsel de erinden uzun sureli yararlanmam z sa layan metotlardan biridir Dondurarak muhafazan n amac depolama s resince kimyasal biyokimyasal ve mikrobiyolojik reaksiyonlar ya t mden durdurulmakta ya da en azaindirmektir Dondurma i lemi s ras ndaki nar nfiziksel ve antioksidan zelliklerinin de i imi ile ilgili yap lan al malar olduk a s n rl ve yetersizdir Bu al man n temel amac h zl IQF ve yava ev tipi dondurulan nar tanelerinin depolanarak farkl z nd rme MW oda s cakl dolap s cakl ve s cak suya dald ma y ntemleri uygulamas ile r n n fiziksel ve antioksidan zelliklerinde g r len de i imlerin incelenmesidir Ayr ca r n n besinsel ve fiziksel zelliklerinde depolama s resinin etkisi de erlendirilmi tir Yap lan incelemeler sonucunda r n n g r n ve besinsel zelliklerinin en iyi korundu u dondurma ve z nd rme y ntemlerinin belirlenmesi ama lanm t r Su s zmas miktar i in elde edilen sonu lar ev tipi dondurulmu nar tanelerinde z nd rme i lemi sonras su s zmas miktar 10 6-24 3 aras nda IQF y ntemi ile dondurulmu rneklerde ise bu de erler 12 4-21 8 aras nda de i kenlik g stermektedir lk aydan sonra ev tipi dondurulmu nar tanelerinde daha y ksek su s zmas de erleri g r lm t r Her iki dondurma y nteminde de en y ksek su s zmas de eri s cak su ile z nd r lm rneklerde belirlenmi tir MW ile z nd rme y ntemi ise r n n dokusal zelliklerinin korunmas i in en uygun y ntem olarak belirlenmi tir 1 ve 8 ay sonu lar n dikkate alarak su s zmas miktar nda en fazla de i im oda s cakl nda z nen rneklerde belirlenmi tir Suda z nen kuru madde miktar brix de erleri ev tipi ve IQF y ntemi ile dondurulmu nar tanelerinde 1 ay y ksek belirlenmi iken depolama s resi boyunca bu de erlerde azalmalar g r lm t r Ev tipi dondurulmu rneklerde brix de erleri 16 2-18 7 IQF dondurulmu rnekler ise 15 0-17 3 aras nda de i im g sterdi i belirlenmi tir Yava dondurulan rneklerde h zl dondurulan rnekler g re daha y ksek sonu lar bulunmu tur Depolama s resi sonunda en y ksek brix de eri dolap s cakl nda z nm rneklerde g r lm t r Depolama s resince r n brix de erlerinde 5 aydan sonra azalmalar belirlenmi tir Titrasyon asitli i ve pH sonu lar na g re ev tipi ve IQF dondurulmu nar tanelerinde depolama s resi boyunca pH de erleri 2 2-3 3 de erleri aras nda de i kenlik g stermi tir Titrasyon asitli i ise ev tipi dondurma y nteminde 11 3-13 7 IQF dondurulmu r nde 10 2-12 7 de erleri aras nda belirlenmi tir Depolama s resince nar tanelerinin pH de erlerinde azalmalar g r lm ken titrasyon asitli inde art lar tespit edilmi tir Nar tanelerinden elde edilen pH ve titrasyon asitli i sonu lar na uygulanan farkl dondurma ve z nd rme y ntemlerinin etkisi olmad belirlenmi tir z nd rme i lemi uygulanmam nar tanelerinde belirlenen ortalama renk parlakl n n g stergesi olan L k rm z rengin g stergesi olan a ve sar renk g stergesi olan b de erleri ise IQF y ntemi uygulanan rneklerde s ras ile 21 4 16 7 ve -2 6 ev tipi dondurulmu rneklerde ise bu de erler 20 2 15 3 ve -2 9 bulunmu tur Dondurulmu nar tanelerinde belirlenen renk de erlerinin L de erleri 20 3-29 1 a de erleri 15 9-29 7 b de erleri ise -0 1 ile -7 9 aras nda de i ti i g r lm t r Dondurma metotlar incelendi inde 1 ay IQF dondurulan rneklerde y ksek de erler g r lm ken 8 ay ev tipi dondurulan rneklerin renk de erleri daha y ksektir Dondurulan nar tanelerinin z nd rmesinden sonra L ve a de erlerinde art belirlenmi tir Ev tipi ve IQF dondurulan rneklerde z nd rme i lemi sonras nda elde edilen 5 ve 8 aylar aras nda L ve a de erlerinde art belirlenmi tir Depolama s resi boyunca nar tanelerinin toplam fenolik madde miktar IQF dondurulmu rneklerde 258 5-136 1 mg GAE 100 g meyve ev tipi dondurulmu rneklerde ise 300 6-152 6 mg GAE 100 g meyve de erleri aras nda de i kenlik g sterdi i belirlenmi tir Dondurulmu rneklerin 1 ve 8 ay sonu lar n inceledi imizde de toplam fenolik madde miktar s cak suda z nen rneklerde g r lm t r Depolama s resi sonunda toplam fenolik miktarlar nda elde edilen de i imler ev tipi ve IQF y ntemi ile dondurulmu rneklerin z nd rme i lemi uygulanmam kontrol gruplar nda art g r lm ken z nd rme i lemi uygulanm nar tanelerinde ise azalma belirlenmi tir IQF dondurulan nar tanelerinin toplam fenolik madde miktarlar nda kontrol grubunda 44 oran nda art MW z nenlerde 12 oda s cakl nda 24 dolap s cakl nda 24 ve s cak su ile z nen rneklerde 8 5 oran nda azalma g r lm t r Ev tipi dondurulmu nar rneklerinin 8 ay sonunda toplam fenolik madde miktarlar nda belirlenen de i imler incelendi inde ise z nd rme i lemi uygulanmayan kontrol grubunda 30 oran nda art MW z nenlerde 6 oda s cakl nda 24 dolap s cakl nda 5 ve s cak su ile z nen rneklerde 23 oran nda azalma belirlenmi tir Her iki dondurma y nteminde uygulanan z nd rme y ntemleri inceleni inde depolama s resi boyunca en fazla de i im oda s cakl nda z nm rneklerde g r lm t r Depolama s resi boyunca nar tanelerinin toplam flavonoid madde miktar IQF dondurulmu rneklerde 74 8-19 0 mg KE 100 g nar ev tipi dondurulmu rneklerde ise 62 5-33 9 mg KE 100 g nar de erleri aras nda de i kenlik g sterdi i belirlenmi tir MW uygulamas ile z nd r lm rneklerde toplam flavonoid miktar daha y ksek belirlenmi tir Depolama s resince elde edilen sonu lardaki de i imler 1 ve 8 ay rneklerinde belirlenen toplam flavonoid madde miktarlar ndan yaralan larak hesaplanm t r IQF dondurulan nar tanelerinde toplam flavonoid madde miktarlar incelendi inde kontrol grubunda 35 MW de 33 oda s cakl nda 44 dolap s cakl nda 26 ve s cak su ile z nen rneklerde 33 oran nda azalma g r lm t r Ev tipi dondurulmu nar tanelerinde belirlenen toplam flavonoid miktarlar ndaki de i imler ise kontrol grubunda 16 MW z nenlerde 12 oda s cakl nda 25 dolap s cakl nda 8 5 ve s cak su ile z nen rneklerde 27 oran nda azalma olarak tespit edilmi tir Toplam antioksidan kapasiteleri CUPRAC DPPH ve ABTS metotlar ile z nd rme i lemi uygulanmam nar tanelerinde IQF dondurulmu rnekler i in s ras ile 1047 3 mg TE 100 g nar tanesi 426 2 mg TE 100 g nar tanesi ve 471 8 mg TE 100 g nar tanesi ev tipi dondurulmu rnekler i in ise 1107 4 mg TE 100 g nar tanesi 629 4 mg TE 100 g nar tanesi ve 805 6 mg TE 100 g nar tanesi olarak bulunmu tur Uygulanan farkl antioksidan kapasitesi belirleme y ntemleri aras nda CUPRAC analizinde en y ksek de erler g r lm t r Depolama s resi boyunca ev tipi dondurulmu nar tanelerinde daha y ksek antioksidan kapasitesi sonu lar bulunmu tur Depolma s resince rneklerin toplam antioksidan kapasitesi de erlerinde azal g zlemlenmi tir Dondurulmu ve z nd r lm nar tanelerinde depolaman n 5 ve 6 aylar nda antioksidan kapasitesi ve fenolik bile en miktarlar nda ani de i imler g zlenmi tir HPLC ile belirlenen fenolik bile en profilleri gallik asit siyanin 3 5-glukozit siyanidin 3-O glukozit delfin 3 5-O diglukozit pelargonidin 3 5-O diglukozit ve pelargonidin 3-glukozit IQF ve ev tipi dondurulumu t m nar tanelerinde bulunmu tur Siyanin 3 5-glukozit ev tipi ve IQF dondurulan rneklerde en fazla belirlenen antosiyanindir Pomegranate with its components is a functional food having an important role in human nutrition Phenolic compounds and polyphenols have important antimutagenic and anticarcinogenic properties due to their antioxidant activity Moreover they have protective effects against cardiovascular diseases High levels of phenolic compounds available in pomegranate and their high antioxidant activity have increased the interest to pomegranate and its products especially juices obtained from pomegranate in the last years Freezing is one of the most important methods for retaining fruits quality during long-term storage Its main objective is the inactivation of the enzymes chemical and biochemical reactions responsible for the deterioration reactions during frozen storage The intensity of this treatment has to assure the enzymatic inactivation while minimasing the possible negative effects of heat on product quality such as degradation of texture and vitamins and colour changes There is limited research related to change of the physical and antioxidant properties of pomegranate during freezing Firstly the present study aimed at investigating the effects of different freezingand thawing conditions on physical drip loss acidity pH colour total soluble solid and antioxidative total phenolic content total flavovoid content and total antioxidant capacity properties of pomegranate arils For this purpose pomegranate arils were frozen at -20 C slow freezing and using the IQF quick freezing and thawing at room temperature refrigerator temperature in a microwave oven and at ambient temperature of 55 C Secondly the effect of long-term storage was investigated on nutritional and physical properties of pomegranate arils and as the result of this study and as the result of this thesis the best freezing and thawing method was determined The results obtained for drip loss analysis showed that drip loss of the conventionally frozen pomegranate arils varied between 10 6-24 3 and IQF frozen pomegranate arils varied between 12 4-21 8 Conventionally frozen pomegranate arils had higher drip loss content after thawing than IQF frozen samples after the first month In both freezing methods the highestdrip loss value was determined in samples was dissolved in hot water and MW was the best method to preserve the textural properties of the pomegranate arils Maximum change in drip loss value was determined the sample dissolved at room temperature during long-term storage The results obtained for total soluble solid brix analysis showed that brix for slow frozen pomegranate arils varied between 16 2-18 7 and quick frozen pomegranate arils varied between 15 0-17 3 Slow frozen pomegranate arils had higher brix value than quick frozen samples In both freezing methods the highest brix values were determined in samples were dissolved at refrigerator temperature Brix values in slow and quick frozen pomegranate arils were high in the first month even though a decrease was seen after the fifth month of storage time pH values ranged between 2 2-3 3 for slow and quick frozen pomegranate arils during long-term storage Titrable acidity values of slow frozen pomegranate arils were measured to range between 11 3-13 7 and quick frozen samples were measured to range between 10 2-12 7 Quick frozen samples had lower titratable acidity value than slow frozen samples While pH values were decreased titratable acidity values were increased during storage time of pomegranate arils The amount of titrable acidity values for slow freezing and quick freezing were approximately similar Lightness L redness a and yellowness b were determined for unsolved slow and quick frozen pomegranate arils The values for slow frozen samples were 20 2 15 3 -2 9 and 21 4 16 7 -2 6 for quick frozen samples Thawed samples exhibited L values ranging from 20 3 to 29 1 a values ranging from15 9 to 29 7 and b values ranging from -0 1 to -7 9 units First month of storage the colour analysis results obtained from quick frozen were higher than slow frozen but at the end of long-term storage slow freezing results were higher L and a values were increased after thawing The L and a values for the samples frozen by two methods increased between 5 and 8 months of storage According to changes during long-term storage total phenolic content for slow frozen and unsolved samples were measured to range between 300 6-152 6 mg GAE 100 g pomegranate arils and quick frozen samples were measured to range between 258 5-136 1 mg GAE 100 g pomegranate arils Slow frozen pomegranate arils had higher total phenolic content than quick frozen samples In both freezing methods the highest total phenolic content was determined in samples were dissolved in hot water Depending on the time of storage analyzed for conventionaly frozen samples total phenolic content suffered a increase of 30 in control group compared with total phenolic content of the first day sample a decrease of 6 in sample thawed with MW a decrease of 24 in sample thawed at room temperature a decrease of 5 in sample thawed at refrigerator temperature a decrease of 23 in sample thawed in hot water compared with control group Total phenolic content of IQF frozen samples suffered a increase of 44 in control group compared with total phenolic content of the first day sample a decrease of 12 in sample thawed with MW a decrease of 24 in sample thawed at room temperature a decrease of 24 in sample thawed at refrigerator temperature a decrease of 8 5 in sample thawed in hot water compared with control group Maximum change in total phenolic content was determined the sample dissolved at room temperature during long-term storage The results obtained for total flavonoid content showed that total flavonoid content of the conventionally frozen pomegranate arils varied between 10 6-24 3 and IQF frozen pomegranate arils varied between 12 4-21 8 during long-term storage In both freezing methods the highest total flavonoid content was determined in samples were thawed with MW Depending on the time of storage analyzed for conventionaly frozen samples total phenolic content suffered a decrease of 16 in control group compared with total phenolic content of the first day sample a decrease of 12 in sample thawed with MW a decrease of 25 in sample thawed at room temperature a decrease of 8 5 in sample thawed at refrigerator temperature a decrease of 27 in sample thawed in hot water compared with control group Total flavonoid content of IQF frozen samples suffered a decrease of 35 in control group compared with total flavonoid content of the first day sample a decrease of 33 in sample thawed with MW a decrease of 44 in sample thawed at room temperature a decrease of 26 in sample thawed at refrigerator temperature a decrease of 33 in sample thawed in hot water compared with control group Among all three different antioxidant capacity methods performed in this study ABTS DPPH and CUPRAC CUPRAC assay provided the highest values for all frozen samples Total antioxidant capacity in slow frozen and unsolved first day pomegranate aril was 1107 4 mgTE 100 g fresh fruit for CUPRAC 629 4 mgTE 100 g fresh fruit for DPPH 805 6 mgTE 100 g fresh fruit for ABTS and for quick frozen sample total antioxidant capacity was 1047 3 mgTE 100 g fresh fruit for CUPRAC 426 2 mgTE 100 g fresh fruit for DPPH 471 8 mgTE 100 g fresh fruit for ABTS Slow frozen pomegranate arils had higher total phenolic content than quick frozen samples for three antioxidant capacity methods Depending on the time of storaged for all frozen samples total antioxidant capacity suffered a decrease of compared with total antioxidant capacity of control group The antioxidant capacity total phenolic content and total flavonoid content for the all frozen and thawing samples changed between 5 and 6 months of storage As a result of phenolic profiling by HPLC analysis gallic acid cyanin 3 5-glucoside cynidin 3-O glucoside dolphin 3 5 glucoside pelargonidin 3 5-O diglucoside and pelargonidin 3-glucoside were found for all samples including slow and quick frozen products Cyanin 3 5-glucoside was found the highest anthocyanin components for all frozen and thawing pomegranate arils Y ksek Lisans M Sc

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