پديد آورنده :
احمدي، شكوه
عنوان :
افزايش طول عمر نگهداري تخم مرغ كامل مايع پاستوريزه و پاستوريزه نشده با استفاده از نگهدارنده بيولوژيك
مقطع تحصيلي :
كارشناسي ارشد
گرايش تحصيلي :
علوم و صنايع غذايي
محل تحصيل :
اصفهان: دانشگاه صمعتي اصفهان، دانشكده كشاورزي
صفحه شمار :
سيزده،82ص.: مصور،جدول،نمودار
يادداشت :
ص.ع.به فارسي و انگليسي
استاد راهنما :
محمود شيخ زين الدين، صبيحه سليمانيان زاد
استاد مشاور :
علي نصيرپور
توصيفگر ها :
نايسين , EDTA
تاريخ نمايه سازي :
14/7/92
استاد داور :
اميرحسين گلي، رحمان جهانيان
چكيده فارسي :
به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي
چكيده انگليسي :
Shelf Life Extension of Pasteurized and Unpasteurized Liquid Whole Egg using Biopreservative Shokouh Ahmadi sh ahmadi@ag iut ac ir Submitted on January 21 2013 Department of Food Science and Technology Isfahan University of Technology Isfahan 84156 83111 Iran Language Farsi Degree M Sc Mahmoud sheikh zeinoddin zeinodin@cc iut ac ir Sabihe Soleimanian zad soleiman@cc iut ac ir Abstract Egg products are widely utilized by the food service industry and commercial food manufacturers Liquid whole egg is one of the important egg products which is made by homogenization and pasteurization of broken whole eggs The initial microflora of LWE is composed of a mixture of Gram positive and Gram negative bacteria similar to the indigenous microflora of shell eggs Low pasteurization temperature limited by the low thermostability of egg proteins and short shelf life of this product suggest that some heat resistant bacteria can survive the heat treatment In recent years the use of bacteriocin as biological preservatives has attracted much attention Nisin produced by lactococcus lactis can be obtained as a commercial product Nisin inhibits the growth of a wide range of Gram positive bacteria Although Gram negative bacteria can be sensitized to nisin by permeabilization of the outer membrane layer as caused by chelating agents like Ethylene diamine tetra acetate EDTA EDTA also has antifungal activity The aim of this study was to investigate the possibility of increasing the shelf life of pasteurized liquid whole egg using nisin and also unpasteurized liquid whole egg using nisin and EDTA in the refrigerator temperature For this study appropriate time and temperature of thermal pasteurization of liquid whole egg in a laboratory scale batch method was determined The shelf life of pasteurized LWE treated with concentrations of 0 3 4 and 5 ppm nisin in the refrigerator temperature were compared Treatments of 5 ppm nisin 5 ppm nisin with 0 5 EDTA and 5 ppm nisin with 1 EDTA were used for unpasteurized LWE Factors measured during storage were total count of bacteria mold and yeast counts and pH values Thermal condition selected for pasteurization of LWE was 63 C for 15 minutes Whereas pasteurized LWE had a shelf life of about 7 to 14 days the results showed a synergistic effect of pasteurization and nisin As to the last day of storage 21th day total bacteria count and molds yeasts were below the limit of detection 10 cfu mL pH values of these samples also showed no significant changes over time p 0 05 Maximum shelf life of unpasteurized LWE was 4 days in the refrigerator condition Adding 5 ppm nisin and 5 ppm nisin with 0 5 EDTA had no significant effect on the shelf life of unpasteurized LWE The treatment of 5 ppm with 1 EDTA had a strong antifungal and antibacterial effect and increased the shelf life of unpasteurized LWE for at least 21 days Using 3 ppm nisin for pasteurized LWE and using 5 ppm nisin with 1 EDTA for unpasteurized LWE in order to extend the shelf life of these products are recommended Key words Liquid whole egg Shelf life Pasteurization Nisin EDTA PDF created with pdfFactory trial version www pdffactory com
استاد راهنما :
محمود شيخ زين الدين، صبيحه سليمانيان زاد
استاد مشاور :
علي نصيرپور
استاد داور :
اميرحسين گلي، رحمان جهانيان
