الفهرس 
ACKNOWLEDGMENT
Incidence of mycotoxins in milk and dairy productsOnly 14 pages are availabe for public view
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Abstract
The present investigation was done to study the mycological evaluation of some dairy products, in the form of 300 random samples of Domiati cheese, Ras cheese and cooking butter (100 each), that were collected from different supermarkets, groceries, dairy shops, farmer’s markets and farmer’s houses in Assiut city, Egypt; during the period from November 2017 to May 2018.
The obtained results revealed that the average count of mesophilic molds in the positive samples of the examined Domiati cheese, Ras cheese and cooking butter samples were 13.33, 97.2 and 2.61×102 cfu/g, respectively; and for psychotrophic molds were <10, 94.62 and 1.33×102 cfu/g, respectively; where for mesophilic yeasts were 1.08×103, 1×103 and 6.15×102 cfu/g, respectively; and for psychotrophic yeasts were <10, 8.74×102 and 5.74×102 cfu/g, respectively; and for mesophilic molds & yeasts (fungi) were 5.9×102, 6.75×102 and 6.98×102 cfu/g, respectively; and for psychotrophic fungi were <10, 8.59×102 and 5.46×102 cfu/g, respectively.
The incidence of the isolated mesophilic fungi species from the examined Domiati cheese samples was represented as Cladosporium sphaerospermum (1%), Penicillium chrysoginum (6%), budding yeasts (6%) and Geotrichum candidum (1%); While, none of the psychotrophic fungi was isolated.
The incidence of the isolated mesophilic fungi species from the examined Ras cheese samples was Aspergillus fumigatus (5%), A. nidulans (1%), A. niger (2%), A. ochraceous (1%), A. terreus (4%), Cladosporium sphaerospermum (4%), Mucor hiemalis (6%), M. racemosus (12%), Penicillium chrysoginum (27%), Pseudozyma rugulosa (3%), Scopulariopsis candida (9%), budding yeasts (37%) and Geotrichum candidum (4%). While, for the isolated psychotrophic fungi species was Cladosporium sphaerospermum (4%), M. hiemalis (2%), M. racemosus (2%), P. chrysoginum (21%), budding yeasts (63%) and Geotrichum candidum (2%).
The incidence of the isolated mesophilic fungi species from the examined cooking butter was A. flavus (1%), A. niger (2%), M. circinelloides (4%), M. hiemalis (16%), M. racemosus (3%), P. chrysoginum (3%), P. crustosum (1%), budding yeasts (38%) and Geotrichum candidum (38%). While, for the isolated psychotrophic fungi was Cladosporium sphaerospermum (1%), P. chrysoginum (28%), Syncephalastrum racemosum (1%), budding yeasts (50%) and Geotrichum candidum (10%).
The percentages of the examined Domiati cheese, Ras cheese and cooking butter samples that agreed with the permissible limits established by Egyptian Standards for molds counts were 99, 68 and 72%, respectively. While, those agreed for yeasts counts were 99, 79 and 37%, respectively.
Part II
Effect of some antifungal treatments on fungal load of cooking butter
A bulk of a purchased cooking butter sample incorporated in the experimental study was soften in a water bath (40º C), then few grams were taken for determination of NaCl% & acidity%, after that the rest of the bulk was taken and immediately divided into 4 equal groups according to the types of added antifungal as followings:
1st group as control (without antifungal)
2nd group with added 32 mg/g bacteriocin, and thoroughly mixed.
3rd group with added 0.3% potassium sorbate, and thoroughly mixed.
4th group with both of 32 mg/g bacteriocin and 0.3% potassium sorbate, and thoroughly mixed.
Each group was subsequently divided into 3 equal portions and stored at different temperature as the followings:
1st portion of the 4 groups was kept at ambient temperature (30±1º C)
2nd portion of the 4 groups was stored at refrigerator temperature (6±1º C)
3rd portion of the 4 groups was stored at freezing temperature (-5±1º C)
The effect of the added antifungal on the molds & yeasts growth at the different temperatures was determined by enumeration of the molds & yeasts at the zero time and then weekly thereafter.
The reduction % of fungi count as a result of the different 4 treatments at the different 3 temperature conditions (ambient, refrigeration & freezing) was measured and showed that the highest reduction % was obtained by the treatment of both bacteriocin & potassium sorbate, followed by potassium sorbate, then by bacteriocin, and lastly by control.
Although the reduction effect of the different antifungal treatments at different temperatures, the preserving effect of refrigeration and freezing was the potent as the different treatments with antifungal plus control were spoiled at 6th week at ambient temperature, while at the same time their corresponding still valid in refrigeration and freezing.