Aims: This study was conducted to determine the effect of starter culture addition on the physicochemical, microbiological and sensory characteristics of white cheese (Gibna Bayda) during the storage period (5°C/ 45 days). Methodology: Two treatments were prepared: Treatment 1 (T1): cheese manufactured with pasteurized milk with Lactobacillus bulgaricus and Streptococcus thermophilus (1:1) at the level of 2% (w/v); Treatment 2 (T2): the control; cheese manufactured with pasteurized milk without starter cultures. After cheese manufacture, physicochemical, microbiological and sensory characteristics were determined at 1, 15, 30 and 45-day intervals. Results: Results showed that the starter culture addition did not significantly (P>.05) affect all physiochemical characteristics of cheese, except for the ash content which was high in cheese manufactured with the addition of starter culture. The addition of the starter influenced the microbiological quality of the cheese, with total viable bacteria, Staphylococcus aureus and yeasts and moulds counts being significantly (P<.05) low. Furthermore, the cheese made with an added starter culture showed high scores of colour, taste and flavour. The storage period significantly affected all characteristics of the cheese, except for the fat content of the control, which remained unchanged during all storage periods. Conclusion: The results of this study show that starter culture (Lactobacillus bulgaricus and Streptococcus thermophilus) (1:1) is likely to be a suitable culture for Sudanese white cheese.

This study was conducted to determine the effect of heat treatment of milk on the physicochemical, microbiological, and sensory characteristics of white cheese (Gibna bayda). The cheese was made from raw warmed (45 °C) milk (T1) and heat-treated (72 °C/1 min) milk (T2) to which the starter culture (2% w/w), sodium chloride (2% w/w) and CaCl2 (0.02% w/w) were added. After manufacture, cheese was preserved at 5 °C for 45 days and subjected to physicochemical, microbiological, and sensory analysis. The results revealed that T2 had longer coagulation time (75.5 min) and higher cheese yield (17.1 kg/100 L) compared to T1. Fat (25.28%), moisture (55.70%), and ash (6.40%) contents were higher in T1, while protein (18.51%), total solids (47.49%) contents, and acidity (0.56%) were high in T2. Total viable bacteria [TVB] (log10 6.64 cfu/gm), Staphylococcus aureus (log10 1.88 cfu/gm) and yeasts and moulds (log10 5.53 cfu/gm) counts were high in T1, while Escherichia coli count was log10 <1.0 cfu/gm in both treatments. T1 scored better in taste (2.43), body (2.26), and overall acceptability (2.79), while T2 scored better in colour (3.44), flavour (2.79), and T2 cheese was slightly salty (1.45) than T1 cheese. The study concluded that heat treatment of milk improved some physicochemical and sensory characteristics of cheese, and heat-treated milk cheese was safer for human consumption than raw milk cheese.

This study was conducted to investigate the effect of starter culture addition on the characteristics of raw milk white cheese (Gibna bayda).The cheese was made from raw warmed (45°C) milk, and the starter culture (2% w/v) was added to the first treatment (T1), while no starter culture was added to the second treatment (T2). After the manufacture, cheese was cut into cubes and kept in the brine solution (2% w/v) for 24 hours, followed by storing without whey at 5°C for 45 days. Microbiological, physicochemical, and sensory characteristics were evaluated at 1, 15, 30, and 45-day intervals. Results showed that total viable bacteria [TVB] (log10 6.73 cfu/gm), Staphylococcus aureus (log10 2.15 cfu/gm), Escherichia coli (log10 1.11 cfu/gm) and yeasts and moulds (log10 6.21 cfu/gm) counts were high in T2 cheese. TVB significantly decreased during the ripening period, while the other microorganisms increased. Fat (25.28%) and total solids (44.27%) were high in T1, while protein (18.44%), moisture (55.77), ash (6.51%), and acidity (0.59%) were high in T2. All physicochemical characteristics except fat were significantly influenced by the ripening period. Taste and body scored best in T1, while the rest of the sensory attributes scored best in T2. All sensory properties were significantly affected by the ripening period except the colour. The study concluded that the use of the starter culture improved the microbiological quality and sensory properties of traditional Sudanese white cheese, which might make this starter culture suitable for this type of cheese.

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Sudanese White cheese (Gibna Bayda) was produced by using different starter culture combinations to find the most suitable starter culture. Four cheeses were prepared with pasteurized milk inoculated with different starter culture combinations at the rate of 1% (v/v), while control cheese (T5) was made without the addition of starter culture. Cheeses were stored in vacuum bags at 4 °C and 15 °C for 90 days, and the properties of cheeses were determined at intervals of 1, 15, 30, 45, 60, and 90 days. The yield of control (T5) cheese was higher than T4 and T1 cheeses and lower than T2 and T3 cheeses. Total solids, protein, fat, and acidity values and lipolysis degree of control (T5) cheese were lower than T4 and T1 cheeses, and higher than T2 and T3 cheeses. The proteolysis degree of control (T5) cheese was the lowest when the cheeses were stored at 15 °C, and the highest among all cheeses except T1 and T4 cheeses when stored at 4 °C. The acidity value, protein, salt, and the degree of lipolysis and proteolysis were higher in cheese samples stored at 15 °C. All sensory properties scored best in T1, T4, and T3 cheeses compared to control (T5) cheese. Cheeses stored at 4 °C scored better for odor and overall acceptability. The use of starter culture in the production of white cheese positively affected the properties of the cheeses, especially T4 cheeses containing Lactobacillus helveticus, and T1 cheeses made with mesophilic culture were better than other cheeses in terms of physicochemical and sensory properties.