Physical, chemical, microbiological and sensory characteristics of some fruit-flovored yoghurt

Kızılcık, kuş burnu, vişne marmelatları, üzüm pekmezi, hurma pulpu içeren yoğurtlarla kontrol grubu (meyve ilavesiz) yoğurt hazırlandı ve 10 gün süreyle 5°C'de depolandı. Meyve aramaları ağırlık oranına göre % 7 oranında yoğurtlara katıldı. Yoğurt örneklerinde bazı fiziksel, kimyasal, mikrobiyolojik ve duyusal özellikleri belirlendi. Örneklerde 1. 6. ve 10. günlerde aerobik mezofilik-bakteri sayısı, koliform bakteri ve maya ve küf sayıları tespit edildi. Örnekler arasında depolamanın 1. günde yağ, kül, protein, toplam kuru madde ve titrasyon asitliğinde önemli farklar bulundu. Farklı aramalardan dolayı yoğurtlarda protein ve kuru madde içeriğinde iz bırakacak farklılıklar gözlemlendi. Depolama periyodunda serum ve titrasyon asilliği arttı. Vişne ve üzüm pekmezli örneklerin, diğerlerine göre, daha fazla tat ve aroma puanı almıştır. Aerobik mezofilik bakteri üzüm pekmezli yoğurtlarda önemli bir şekilde daha yüksek bulundu. Maya ve küf sayısı 5°C'de depolama süresince önemli olarak artış gösterdi.

Anahtar Kelimeler:

duyusal değerlendirme, yoğurt, fiziksel özellikler, mikrobiyolojik kalite, kimyasal özellikler, gıda katkı maddeleri

Bazı meyve aromalı yoğurtların fiziksel, kimyasal, mikrobiyolojik ve duyusal özellikleri

Yoghurt with different jfruit-flavors(Cornelian, Morello Chery and Rose hip marmalade, grape molasses, date pulp, and control (without additive)) was prepared and stored up to 10 days at 5°C. The fruit flavors were added at the rate of 7 % w/w. Yoghurt samples were analyzed for some physical, chemical, microbiological and sensory some characteristics. The total aerobic mesophilic bacterial count, coliform count, and yeast and mold counts �were determined in yoghurt samples at 1, 6 and 10 days interval. There were significantly differences in the fat, ash, protein, total solids (TS) content and titratable acidity (TA)for samples amonts Id of storage. There were marked differences in the protein and dry matter due to different flavor additives. Syneresis and TA increased over the storage period. The yoghurt containing Grape molasses and Morello had higher flavor scores than using other flavoring. The total mesopilic bacterial count was significantly higher in the yoghurt sample contained grape molasses. Yeast and mould count increased significantly during storage at 5° C .

Keywords:

sensory evaluation, yoghurt, physical properties, microbiological quality, chemical properties, food additives,

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