Microbiological and biochemical aspects of Kishk fermentation : 1-whey Kishk

Abstract EN

Nowadays, there is a great interest of functional foods; however, Kishk is one of the oldest forms of bio preservation.

It represented a native food in Egypt and Middle East.

It formulated mainly from fermented milk and burghul (cracked parboiled wheat).

In the present study an acceptable whey-based kishk was prepared by utilizing burghul with the addition of whey by pure or mixed culture of Streptococcus thermophilus and/or Lactobacillus delbrueckii subsp.

bulgaricus in substitution of fermented milk depending on its high biovalaibility, biological value and its role as buzz healthful product.

Water-based kishk play as control.

Six treatments of both of whey and water kishk were analyzed chemically for titratable acidity%, pH value, total solids%, ash content, fiber content, total carbohydrate, free amino nitrogen.

Microbiological examination including total and actidione resistant yeast, lactic acid bacteria, sporeforms, total plate count, staph.

aureus and coliforms.

Treatments were analyzed every 6 hrs during dehydration at 45?C (fermentation period), and during storage for 60 days at both of 22 and 37?C as ambient temperature in summer and winter seasons.

Results indicated that S.

thermophilus and L.

bulgaricus were dominant during dehydration in both of whey and water Kishk in around of 8 log cfu/ml.

Also, total acidic and actedione resistant yeast, spores, fungi were presented during fermentation.

However, storage at all temperature caused a decrease in S.

thermophilus and L.

delbrueckii subsp.

bulgaricus counts which was proportional to the storage period and the temperature of storage used.

Water kishk had little content of titratable acidity which affect on its acceptances whilst whey kishk was in visa versa.