| Titles |
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English :
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EFFECT OF SKIM MILK POWDER SUBSTITUTION WITH BARLEY FLOUR ON THE PROPERTIES OF PROBIOTIC FRUIT FLAVORED STIRRED YOGHURT
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Arabic :
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تأثير استبدال اللبن الفرز بدقيق الشعير على خواص الزبادي المقلب و المنكهة بالفواكه
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| Abstract |
This study aimed to investigate the effect of skim milk powder substitution with barley flour on chemical, microbiological and sensory properties of probiotic fruit flavored stirred yoghurt.
Skimmed milk powder was replaced by 25%, 50%, 75% or100% with barley flour, fatted with 3% coconut oil, homogenized, cultured with 3% mixed culture (1:1)Lactobacillus acidophilus ATCC4495 and Bifidobacterium lactis Bb-12 and stirred. Strawberry or mango juice containing 50% sugar was added to all treatments at level of 15% and cold storage at 4-5?C for 15days.
The obtained results indicated that, The fruit flavored stirred yoghurt contained 17.24-20.75% total solids (TS), 2.28-3.75%. protein, 2.85-3.20% fat, 0.76-1.62% ash and 9.78-13.64% carbohydrate. Substitution of skim milk powder by barley flour decreased the total protein and increased the ash, carbohydrate and total solids contents, but didn’t have any effect on the 3% added fat. Increasing the replacement percentage or storage period gradually increased the titratible acidity (TA)% and decreased the pH values. The highest TA% and the lowest pH values were recorded at the end of storage period (ranged from 1.12 to 1.67% and 3.71 to 4.12, respectively). Microbiologically, the log10 cfu/ml of both L. acidophilus and Bif. lactis initially(after one day) ranged from 7.82 to 8.45, 7.93 to 8.45, respectively, and gradually increased to reach the maximum then decreased thereafter in all treatments. Barley – containing treatments showed higher counts of lactic acid bacteria than control. Total microbial count, yeasts and moulds increased gradually by increasing both of substitution percentage or storage period, so maximum counts were observed in those of 75% and 100% barley treatments. Coliform bacteria were not found in any sample along the storage period. Organoleptically, All barley treatments recorded higher organoleptic scores than control, but that of 50% barley flour gained the highest one. Gradually decrement in the panel score was noticed by increasing the storage period of all treatments till the end of cold storage period.
In conclusion, 50% barley treatment of fruit flavored (whether with strawberry or mango) stirred yoghurt have more acceptable organoleptic properties and higher numbers of probiotic bacteria with moderate amounts of nutrients and total acidity.
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| Publication year |
2009
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| Pages |
47:93
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| Organization Name |
Food Technology Research Institute (FTRI)
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| serial title |
ِAnnals of agric.sci,moshtor
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| Author(s) from ARC |
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| External authors (outside ARC) |
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| Publication Type |
Journal
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