The effect of microwave power levels, frying time, and temperature on mass transfer and acrylamide formation during deep-fat frying of carrot slices was determined.Maximum and minimum moisture loss were measured, respectively, in control samples fried at 170°C for 4 min and samples pretreated with microwave at 7 W/g power and fried at 150°C for 2 min. The highest (0.69 g/g) and lowest (0.42 g/g) oil uptake were observed in control samples fried at 150°C for 4 min and samples pretreated with microwave at 7 W/g power and fried at 150°C for 2 min, respectively. The effective moisture diffusion and activation energy ranged from 4.84 × 10 −10 to 15.41 × 10 −10 m 2 /s and from 6.47 to 11.75 kJ/mol, respectively. The highest (19.83 µg/kg) and the lowest (<4.67 µg/kg) amount of acrylamide formation were, respectively, measured in control and in microwave pretreated samples (with 7 W/g power for 3 min and fried at 150°C for 2 min).Novelty impact statement: Using microwaves as a pretreatment could significantly reduce oil uptake and acrylamide formation in carrot samples. A reduction in acrylamide was observed in this study after increasing the microwave thermal power from 3 to 7 W/g. Some studies have shown that the acrylamide content increases by increasing the thermal power of the microwave. This study reports that the acrylamide content is a function of the processing time, and the increasing thermal power of the microwave reduces the acrylamide content in short processes.

In cheese, the reduction of salt is still a challenging task, as sodium chloride exerts multiple and fundamental functions. Salt favors the drainage of the residual whey; enhances the taste and the aroma profile; regulates the texture, the final pH, and the water activity; and affects the microbial growth. Hence the impact of partial replacement of NaCl by KCl on the ripening characteristics of Iranian UF (ultrafiltration) cheese during storage was monitored. To produce low-salt cheese, different mixtures of UF white cheese were treated with NaCl : KCl ratios of (a) 3% NaCl (control), (b) 1.50% NaCl+1.50% KCl, (c) 1.00% NaCl+2.00% KCl, and (d) 0.75% NaCl+2.25% KCl by dry salting. ADV (acid degree value) results showed significant differences ( P < 0.05 ) in all treatments after 15, 30, 40, and 50 days of ripening. No significant differences were observed in the GC (gas chromatography) results in the samples’ free fatty acid (FFA) profile except for C18 : 0 in all treatments. KCl did not affect the moisture, dry matter, fat, TN (total nitrogen)/dry matter, and WSN (water-soluble nitrogen) contents of cheeses considerably. The evaluation of force to fracture showed that there were significant differences ( P < 0.05 ) between treatment (d) as a control cheese and treatments (b) and (c). Sensory evaluations showed as the concentration of KCl increased, the cheese gradually became less acceptable and treatments with higher potassium chloride content were crumblier and less firm. Results of the aroma evaluation of cheese samples showed that unlike acetaldehyde, ethanol, acetoin, and diacetyl amounts decreased significantly ( P < 0.05 ) during the storage period. Results also indicated that a reduction of sodium by up to 50% did not significantly affect the quality and composition of Iranian low-salt UF-white cheese except for sensory evaluation, texture analysis, and aroma characteristics.

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The present work determined the effect of Bifidobacterium bifidum and Enterococcus faecium incorporation on the qualitative attributes of ultra-filtrated (UF) Feta cheese. The alterations in pH, titratable acidity, proteolysis, and lipolysis were evaluated during 60 days of refrigerated storage. Viable count, optical analysis, and sensory evaluation were also performed on the freshly made cheeses throughout the storage period. Results showed that incorporating B. bifidum and E. faecium, either individually or in combination, significantly decreased the pH values as compared to control. Cheeses incorporated with E. faecium had significantly higher titratable acidity, proteolysis, and lipolysis than the other treatments. Probiotics counts were higher than 106 CFU/g at the end of the storage period. Co-inoculation of both probiotics did not enhance the viability of either. Moreover, the colour of UF Feta cheeses was not influenced by the incorporation of B. bifidum and E. faecium. The other sensory features remained unchanged on the first day of refrigerated storage. Overall, B. bifidum and E. faecium could be promising species for industrial production of probiotic UF Feta cheeses.

Cheese is an excellent source of nutrition (particularly protein, calcium, phosphorus, and vitamins including A and D) and possesses high bioavailability and palatability (Uliescu et al., 2007). Grade milk and dairy products are an important and readily accessible source of animal-origin protein in the human diet. Lighvan, a traditional, semihard cheese, is produced mainly in northwestern Iran from raw sheep's milk or mixtures of sheep's and goat's milk, without a starter culture. The breeds of sheep and goats used for production of Lighvan have a lactation period of about 6 months; thus, Lighvan cheese production cannot be veritably extended throughout the year. As a result, pasteurized milk is commonly used in making Lighvan. Despite the safety concerns associated with the use of raw milk, there is still a large demand in Iran and elsewhere for raw milk cheeses (Cakir et al., 2016) because they possess strong and unique flavors. At the industrial level, the ripening period for the industrial production of cheese is 45 to 90 days, but raw milk cheeses made by

Deep frying is one of the most common operations used in food processing. But it is necessary to use methods to reduce the oil uptake and prevent the formation of toxic substances such as acrylamide, while maintaining the desired features. Accordingly, in the present study, the effect of microwave pre-treatment with the power of 2 and 5W / g and in 15 and 10 minutes respectively, on the amount of oil uptake and the amount of acrylamide formation in fried carrot pieces was investigated at two temperatures of 150˚C and 170˚C and in 2 and 4 minutes duration. According to the results, at all temperatures, with increasing of the frying time, the amount of oil and the acrylamide formation increased in all samples, but at the same frying times, control samples had higher oil uptake and acrylamide formation compared to the pre-treated samples. According to the investigations, the highest oil uptake and the highest amount of acrylamide formation were respectively measured in the samples fried at 150˚C in 4 min (6.12%), and the fried samples at 170˚C and in 4 min (18.49 ppb). However, the lowest amount of oil uptake and acrylamide formation in microwave pre-treated samples (with 5W/g power in 10 minutes) and samples fried at 170˚C in 2 minutes were respectively (3.78%) and (<4.67 ppb).

Cheese is a potential food carrier of probiotic microorganisms to the human gastrointestinal tract due to its dry matter, fat and higher pH. Due to the emphasis of health organizations on promoting the consumption of healthy dairy products and consumers' desire to eat healthier foods, in this study, the feasibility of producing probiotic UF cheese containing probiotic strains of Bifidobacter bifidum, Enterococcus fascium was studied singly or in combination. Survival characteristics of probiotic strains log cfu / g; Effective compounds in aroma including (acetaldehyde, diacetyl) and sensory evaluation including scores (odour and flavor) were evaluated during the 60-day ripening period.The treatments used in this study included treatments A: ordinary UF cheese as a control treatment, B: probiotic UF cheese containing Bifidobacterium bifidum, C: probiotic UF cheese containing Enterococcus faecium and D: Probiotic UF cheese containing a combination of Bifidobacterium bifidum and Enterococcus faecium.The results of this study showed that the rate of survival of probiotic bacterial population decreased during the 60-day storage period. However, at the end of the storage period, all treatments had more than 10 6 cfu/ g with probiotic bacteria. The amount of acetaldehyde in the whole treatment increased during 60 days of storage period. The amount of diacetyl increased only in treatment A (control) during the 60-days of storage period and a decreasing trend was observed in other treatments. The sensory score for odour of all treatments increased during the 60days of storage period. Sensory score for flavor increased during 60-days of storage period. In general, according to the survival, aroma and sensory evaluation characteristics, treatment D had relatively better characteristics compared to other treatments.

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