بررسي توليد و پايداري نكتار و شربت آلبالو و پرتقال كم كالري با استفاده از شيرين كننده استويوزيد

چكيده انگليسي :

Evaluation of production and stability of low Calorie sour cherry and orange drinks and nectars using stevioside sweetener Samane Hosseini Samane hosseini@ag iut ac ir Submitted on January 1 2013 Department of Food Science and Technology Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Seyed Amir Hossein Goli amirgoli@cc iut ac ir Javad Keramat keramat@cc iut ac ir Abstract Nowadays low calorie products are very much popular One of the way to produce low calorie food is replacement of sugar with low calorie sweeteners Sweeteners are divided in two main group caloric nutritive and noncaloric non nutritive compounds A lot of these artificial compounds have harmful effects on the health so a number of highly sweet plant derived sweetener are used recently that one of them is stevioside This compound isolated from the leaves of the Paraguayan plant Stevia rebaudiana Bertoni Stevia is a small shrub and the eight diterpene glycosides are responsible for sweetness taste of stevia leaves Stevioside is the most important of these diterpene glycosides It is a white and crystalline powder and approximately 300 times sweeter than sucrose Fruit juice consumption is necessary because fruit juices are considered to be rich sources of vitamins minerals and phenolic compounds Orange and sour cherry juices are popular beverages with an important role in human nutrition Production of low calorie orange and sour cherry nectars containing 60 natural juice and juice drinks containing 30 natural juice by response surface methodology RSM was the purpose of this study Three different levels of independent variables sugar stevioside and pectin were used to optimize formulations and two responses of brix and viscosity were determined After the determination of the best formula they were produced and pasteurized for 2 minutes at 80 These products were stored at refrigerated 4 and ambient 25 temperatures for 60 days and some of physicochemical properties were measured each 20 days The results showed that after 60 days storage at 4 sucrose was significantly decreased at the significance level of 99 while glucose and fructose contents increased Stevioside content was reduced after two month storage at 4 Total monomeric anthocyanins were decreased from 65 95 to 56 27 and 30 9 to 26 4 mg cyanidin 3 glucoside per liter after 60 days storage at this temperature in sour cherry nectar and juice drink respectively Amount of carotenoids in orange nectars and juice drinks were decreased almost 50 Vitamin C turbidity viscosity and L a and b values were also reduced during storage These changes were greater at higher storage temperature 25 Browning index and acidity were increased after 60 days but brix didn t change over the study At the end of the storage at 4 there was no significant difference between blank samples without stevioside and optimal treatments for pH acidity L a and b values Optimal treatments had higher turbidity total phenolic contents and vitamin C and lower browning index than blank samples Finally results showed that it is possible to produce sour cherry and orange nectars and orange juice drink by sugar content reduction up to 70 in their formulation by using stevioside and pectin with maximum levels of 0 06 and 0 04 respectively Keywords Stevioside Nectar Juice drink Orange Sour cherry Response surface methodology

حسيني، سمانه

بررسي توليد و پايداري نكتار و شربت آلبالو و پرتقال كم كالري با استفاده از شيرين كننده استويوزيد

شربت ميوه , روش آماري سطح پاسخ