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A single column cation exchanger resin was used to eliminate cations from renet cheese whey, with particular reference to the improvement of taste and flavor. Ten panelists were convened to assess the contribution of the mineral components to the salty taste of whey, judging on the basis of taste, flavor and color. The organoleptic characteristics of untreated whey were arbitrarily assigned a score of zero and the best treated whey in terms of quality, a score of 20. The use of a strong-acid cation exchange resin resulted in the removal of 28% of the calcium and 45% of the magnesium from treated whey with a concomitant increase in the concentration of sodium. The average score of treated whey increased from zero, for untreated whey, to 19.7 for the first element of whey passed through cation exchange resin.

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In this study, the optimum combination of major factors affecting the acceptability of whey-based Ricotta cheese i.e. fat at three levels (0, 5, 10%), salt at three levels (0, 1, 2%), and starter culture at two levels (0, 3%) was determined in a complete randomized design method with a factorial experiment. Ricotta cheese trials made by mixing whey and milk in a ratio of 5:1 were then organoleptically judged on the basis of the main attributes such as color, flavor, texture, and overall acceptability. The collected data were then statistically analyzed using a seven point hedonic method. The results show that the addition of fat had a significant effect on all sensory attributes (p< 0.05). The incorporation of salt in the formulation also had a significant effect on flavor, color, and overall acceptability (p< 0.05) as well as on texture (p< 0.01), whereas the addition of starter culture had a significant effect only on texture (p< 0.01) and overall acceptability (p< 0.05). It was concluded that a combination of 5% fat, 2% salt, and 3% starter culture gains a higher score and could be recommended as the preferred formulation for Iranian consumers.

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Little would be gained by discussing the nutritive value of bread in human diet. Fortification of bread with protein especially whey powder has been the center of attention in many countries. In this study Hamburger dough's containing 0.5, 1, 1.5, 2, 2.5, 3, 4.5 and 7.5 percent whey powder were Prepared. Chemical composition of whey powder and wheat flour was measured and also dough rheological properties were evaluated by ICC and AACC methods. Regarding rheological results, treatments contained 3 and 7.5% whey powder were prepared. Crust color, crumb texture, flavor and volume of breads were evaluated by ten expert and trained panelists using a 0-9 point scale. Overall acceptability of breads was ranked by Phisher and Yaths method. The effect of whey powder on the staling rate of bread was evaluated by scoring test. Development time and resistant of doughs containing 1.5% and 7.5% whey powder was increased. Valorimetric value of dough with 7.5% whey powder was higher than other treatments. Addition of whey powder increased the elasticity of dough's and improved the volume and quality of breads. The result of sensory analysis indicated that crust color, crumb texture, flavor and volume of Hamburger bread containing 3% whey powder achieved highest score and the rank of this treatment concerning the overall acceptability was highest. From staling rate point of view mean scores of samples contained 3% and 7.5% whey powder were greater than control. Regarding the chemical, rheological and sensory characteristics, Hamburger bread contained 3% whey powder was considered the best.

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The aim of this research was to study the effects of whey protein concentrate (WPC) and casein hydrolysate (CH) on chemical (pH and titratable acidity), physical (consistency and syneresis) and sensory properties of yogurt containing probiotic bacteria. Reconstituted skim milk at 10% total solids was fortified with 1 and 2% of WPC, CH and blend of them (WPC to CH ratios of 1:1). Reconstituted skim milks were made with 11 and 12% total solids as control. Bioyogurts were prepared with commercial probiotic starter culture (Lactobacillus acidophilus, Bifidobacterium sp., Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus). Fermentation was stopped at pH=4.6 and samples stored at 4°C for 21 days. Addition of WPC resulted in the highest pH value and the lowest titratable acidity. Acidity values of supplemented bioyogurt samples increased between 0.12 - 0.19% during 21 days of storage. Mَoreovere syneresis of these yogurts was lower and their consistency was higher than control. Bioyogurts containing WPC had the lowest syneresis and samples containing CH or WPC had the highest consistency. With regards to total acceptability, the best samples were bioyogurts supplemented with WPC and blend of WPC and CH.

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The aim of this research was to study the effects of whey protein concentrate (WPC) and casein hydrolysate (CH) on chemical (pH and titratable acidity), physical (consistency and syneresis) and sensory properties of yogurt. Reconstituted skim milk at 10% total solids was fortified with 1 and 2% of WPC, CH and blend of them (WPC to CH ratios of 1:1). For comparison, reconstituted skim milks were made with 11 and 12% total solids as control. Yogurts were prepared with commercial starter culture (Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus) and their fermentation proccess were stopped at pH=4.6 and samples stored at 4°C up to 21 days. The lowest pH value was obtained when milk base was supplemented with WPC. pH values of all yogurt samples did not change significantly during 21 days of storage and ~0.18% increase in titratable acidity was observed during storage period. The lowest syneresis was observed in yogurts containing blend of WPC and CH. Moreover, the syneresis values of these yogurts increased slower than other samples during storage. Consistency of fortified yogurts was higher than control yogurt and the consistency values of these samples reduced slower than control sample during 21 days of storage. With regards to total acceptability, the best samples were yogurts supplemented with blend of WPC and CH.

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  Addition of 8%, 12% and 16% skim milk to fresh whey was studied to prepare indigenous fermented milk by industrial method. G3mix mesophil starter culture and Y709, V2 thermo Phil starter cultures were used and fermentation was performed with 2% starter cultures. The effect of the essence, the amount of skim milk added to whey, the percentage of salt added to fermented milk beverage and the presence or absence of gas was studied in the samples. Results show that carbonated samples containing spearmint or pennyroyal essence with 1% salt and 16% skim milk is the best desirable among others. The desirability of the samples containing Y709 starter culture at the above levels is comparable to the extent of the market samples and samples containing V2 and G3mix starter cultures were lower desirability respectively. The amount of total solid content of samples containing G3mix, V2 and Y709 starter cultures are 6.98%, 6.37%, 6.06% respectively as compare with the market sample of 5.02% is obviously higher. The fermented milk beverage produced form whey being cheep, desirable quality, easily competitive with market samples and can be produced industrial.

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Nowadays the lack of food specially protein is the most important problem. Because of the increasing of  the world population the need for food is increasing day by day for this reason researches are searching for cheap resources of  protein for people. Whey is by- product of  cheese factory. whey provides ecological problems because of  having high COD. According to these problems many researches have been done on whey and different products were achieved such as single cell protein. In this research, the production of  single cell protein from whey and trichosporon yeast are studied in external loop airlift reactor. Effective factors on gas hold up Such as air giving, ratio of  down comer diameter to riser diameter and height of  liquid in gas separator were studied and optimized. In this optimized situation the rate of  single cell protein was achieved. The results of  experiments showed that optimimum value for air giving intensity was 2.27 cm/s , ratio of  down comer diameter to riser diameter was 0/5 cm and height of liquid in gas separator was 3 cm. In this optimum condition, the amount of  single cell protein was 18.9 g/l. The rate of  single cell protein in stirred reactors and bubble column was 10.38 and 17.3 g/l respectively in other^'s researches. In comparison, external loop air lift reactor showed an increase about 8.5 percent to bubble column and 45 percent to stirred reactor in producing single cell protein. So external loop air lift seems suitable in producing single cell protein. producing single cell protein can be studied in Other air lift reactors such as internal loop airlift reactors and obtained results can be campared with the results of  this research.

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  The goal of this study was to determine the changes of diacetyl content and sensory charactristics  of  yoghurt fortified with whey protein concentrate instead of skim milk powder at storage condition. Our finding showed that with increasing in amount of whey protein concentrate in yoghurt samples, diacetyl level was always higher than control sample. Diacetyl amounts also in yoghurt samples increased during two weeks. The results of sensory evalution also showes  that there was no difference in flavour between control sample and sample C but quality characteristics (flavour, general acceptance) other samples were different from control sample. Results indicated that during storage period quality characteristics, especially improving consistency , creamy texture and more flavouring compounds produced acceptance sample C were close to control sample.  

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The effect of edible whey protein coating and dill (Anethum graveolens) essential oil on the quality and shelf-life of silver carp’s fillets, Hypophthalmichthys molitrix,during refrigeration storage was evaluated. Fillets were immersed in whey protein solution (10%), dill essential oil (5%) and a mixture of whey protein (10%) and dill essential oil (5%), then packed and stored in refrigerator (4˚C). Chemical (PV, TBA and TVB-N) and microbial (TVC and PTC) parameters were measured at 0, 3, 6, 9, 12, 15 and 18 days. The amount of peroxide value and thiobarbitoric acid significantly increased (P < 0.05) in all treatments, but this increace was lower in whey protein coating with dill essential oil fillets. Total volatile basic nitrogen of dill essential oil, whey protein and whey protein with dill essential oil treatments in the first and last phase of storage were 7.55, 7.60, and 7.51- 24.11, 25.84 and 15.55 mgN₂/100 g fillet, respectively. The TVC and PTC amount for whey protein with dill essential oil was lower in comparsion with other treatments. Thus, whey protein coating with dill essential oil increased the shelf-life ofsilver carp’s fillets during refrigerated storage. 

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Recently, many studies have been conducted to produce lactic acid. At present study, lactic acid production conditions from whey, in batch fermentation, by Lactobacillus casei were studied to optimize culture medium, using Taguchi method. Four different concentrations for nitrogen sources; yeast extract, peptone and ammonium sulfate; and 3 levels for temperature and shaker rate were selected. At predicted optimum conditions by Taguchi analysis, in batch fermentation and without pH control, after 24 hrs incubation, 12.5 g/lit lactic acid was obtained.  

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  The aim of this work was to study the effect of adding gellan gum and glycerol to film-forming solution on physical and mechanical properties of whey protein/gellan gum emulsion films and to produce edible coatings from whey and gellan gum and determine its effect on storage life of apricot. Whey protein coatings were prepared by dispersing 10% protein in distilled water; and plasticized with glycerol(Gly). Also gellan gum was added at different levels(0, 0/2, 0/4 and 0/6gr). Therefore apricots were dipped in this coatings solution for 1 minute at 20˚C and air dried. Coated fruits together with the uncoated fruits(control) were placed in open dishes and stored at 4˚C and 85% RH for 1 months. Weight loss, total soluble solid(TSS), titrable acidity, pH, skin color, flesh firmness and overall acceptability of coated apricots and control were measured weekly.  The result revealed that the weight loss and changes in the quality parameters were much lower in coated apricots as compared with those. Color changes were also studied using a Hunter lab colorimeter. Finally results showed that the applications of whey coating increased overall acceptability, quality and storage life of apricot, while decreased its weight loss during storage. The emulsion films were evaluated for physical and mechanical properties. Increasing the level of gellan gum in the films led to increase in Modulus(EM) and Tensile Strength(TS) but increasing gum to 0/6gr made less increase in Modulus(EM) and Tensile Strength(TS). About Elongation(EL), was observed increase too but in films that produced with 0/4gr gum, there was a slight decrease.

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In this study, physicochemical properties, sensory characteristics and shelf life of muffin prepared by substitution of egg white with different levels of whey protein concentrate (WPC) were evaluated. WPC at three levels – 25, 50 and 75 %– was considered as variable treatment. Physicochemical properties including butter pH, butter consistency, cake pH, weight loss, density, moisture, shelf life properties including water activity () and hardness after 1, 2 and 10 days storage and sensory properties including crust color, taste, texture and total acceptance were measured and the result were analyzed. Data analysis showed that WPC substitution levels affected all of properties.  In comparison with control butter pH, cake pH, moisture, density,   and hardness after 1, 2 and 10 days storage decreased whereas consistency and weight loss increased with increase of substitution level. Also WPC substitution levels affected all of sensory properties. Color score increased with 25 and 50 % WPC but decreased with 75% WPC. Texture, taste and total acceptance scores decreased with increase of substitution. No significant difference of taste and total acceptance scores with control up to 50 % replacement level was noticed; however it became significant at 75% replacement level.  

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Antimicrobial packaging is a form of active packaging that could extend the shelf-life of foods and provides microbial safety for consumers. In order to control undesirable microorganisms on food surfaces, volatile and non-volatile antimicrobial agents can be incorporated into polymers. Incorporation of essential oils and other antifungal agents in edible films composition is an antimicrobial packaging that able to inhibit fungal growth on the pistachio and aflatoxins production. The antifungal activity of Sage (Salvia officinalis) extracts against Aspergillus flavus in whey protein concentrate-based coating on pistachio kernels was investigated. The antifungal effect of Sage extracts was investigated in culture media by direct method (well method) and application of whey protein concentrate (WPC) films as discs (disc method) incorporated with different concentrations of extracts. In order to evaluate the antifungal effect of extract in pistachio, kernels coated with different concentrations of extract inoculated with a culture media discs contain 9-day-old growing A. flavus colony and the growth rate of inoculated discs were measured during 1 week. In experimental condition, minimal inhibition concentration was achieved by 155 ppm of ahcoholic extract (30 percent concentration). The results also showed that WPC coating incorporated with 4000 ppm of Salvia officinalis extracts on pistachio kernels inhibited A. flavus growth totally. Paying regard to economical aspects of importance of contamination with toxigenic fungi in pistachio kernel suggest the application of Sage extract incorporated in edible coatings for toxigenic fungi growth and toxin production in foods.   

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Supplying fresh fish and sea products is accompanied with the problem of their rapid spoilage and short shelf life. Therefore, solutions which help increase this shelf life have always been valued. Accordingly, the aim of this study was to evaluate the effect of whey protein coatings containing four different concentrations (100,200,400 and 800 IU/gr) of nisin in perch fillet for storage in refrigerator temperature. Humidity tests, Peroxide Value, Thiobarbituric acid Index, microbial load, water activity and pH were performed over coated and uncoated samples. The results indicated that increasing the shelf life in all treatments led to an increase in peroxide value, Thiobarbituric acid Index, the load of bacteria, pH and water activity, this increase was less in coated samples than the uncoated ones. On the other hand, the findings showed that whey protein and nisin coating with the of concentration 400 IU/gr of perch fillet can add 16 days to increase the shelf life in refrigerator temperature in comparison with the uncoated samples. Based on our findings, it can be concluded that using whey protein coating containing nisin with the concentration of 400 IU/gr of perch fillet as edible coating  can increase the shelf life in the refrigerator temperature.

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Yog-ice cream (frozen yogurt), is a kind of frozen desserts which has similar features with ice cream in physical and apparent characteristics. In this study, frozen yogurt was produced as a synbiotic product containing both probiotics and prebiotics. Lactobacillus Casei(LAFTI-L26)as a probiotic bacteria was added to low fat frozen yogurt in two types;free and encapsulated,and its survivability was evaluated during 30 days storage at -18^oc.Prebiotic compound that was used in this study,was Inulin that added to frozen yogurt in different levels(0,2.5 and 5% w/w). The viable cell number of L.casei in the free state in prepared low fat frozen yogurt mixture, was between 9.801-9.779 log cfu/ml at the first day, and after 30 days storage at -18^oc,its viable number redused to 7.451-7.866 log cfu/ml. In samples of frozen yogurt containing L.casei that was encapsulated by sodium alginate-whey protein concentration(wpc),the viable cell number of L.casei was 8.150-8.661 log cfu/ml  at the first day that reduced to 6.650-7.477 log cfu/ml at the end of 30 days storage at -18^oc.Totally ,obtained results showed that encapsulation of lactobacillus casei in Alginate-Whey protein capsules, could significantly improve survivability of L.casei.(p<0.05) that the viable number of this bacteria in frozen yogurt containing encapsulated probiotic,was in the range of investigated levels by the International Dairy Federation(10⁶-10⁷ cfu/g).

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Proper conditions for producing crude beta-galactosidase from waste materials were de-termined. This enzyme is to be used in the production of lactose-hydrolyzed milk. Whey permeate was used as a basic medium. Twenty seven treatments were developed by 3 vary-ing factors of: yeast extract (1, 2, and 3 %), wheat steep liquor (1, 2, and 3 %), and whey powder (0.5, 1, and 1.5 %). Crude enzyme extract was obtained by sonication of the cells collected from cultivation of Lactobacillus delbrueckii ssp. bulgaricus in various media at 43oC. The beta-galactosidase activity was assessed using Ortho-Nitro-Phenyl-beta-D-galactopyranoside (ONPG). Yeast extract and whey powder had both significant effects (P< 0.01), while wheat steep liquor proved to be ineffective. Yeast extract had the most pro-nounced effect on the production of beta-galactosidase. The effect of the interactions of yeast extract-whey powder and wheat steep liquor-whey powder were significant at 5 % level (P< 0.05), while the effect of the interaction of yeast extract-wheat steep liquor was sig-nificant at 1% level (P< 0.01). Interaction effect of the 3 factors on the production of beta-galactosidae was significant (P< 0.01). The best combination for production of beta-galactosidase (4.924 U ml-1) was 3% yeast extract, 1.5% whey powder and 2% wheat steep liquor.

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  One of the most important researches areas in food industry is setting parameters in an optimal level to improve process functions. A literature research in food science and technology databases reveals that in recent years many optimization methods have been developed to improve food processing. However, most of these methods have only dealt with a single objective problem. In many situations the quality of a manufactured product is often evaluated by several quality characteristics and multiple objectives must be optimized simultaneously. In this article we propose a method that integrates design of experiments, response surface technique and Signal-to-Noise (SN) ratio concept for optimization of a kind of yoghurt, called Whey Less, with three objectives: TS, Acidity and cost per unit. The proposed method considers both the mean and the variation of quality losses associated with several objectives, and ensures a small variation in quality losses among the objective functions, along with a small overall average loss. Moreover, this method can be used for both kinds of decision variables (discrete and continuous) and its implementation is easy.  

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Background: Carotenoids are biological antioxidants and play important roles in protecting the body from diseases and aging. Canthaxanthin is one of the most widely used carotenoids in the industry and medicine. This study aimed to investigate the biological properties of canthaxanthin pigment as well as its production optimization in a low-cost medium using a radioresistant microbial strain named Dietzia maris.
Materials and methods: Bacterial carotenoids were extracted and its antibacterial, anti-tumor, and cytotoxicity properties were investigated. Then, the effect of Krebs intermediates and pH on the production of pigment and microbial biomass in the whey medium was investigated using the response surface methodology.
Results: Maximum pigment production was found to be 92/54 mg/l in whey culture medium at pH 8 and in the presence of 12.5 mM of each of citrate, glutamate, malate, and succinate by the response surface method. The pigment did not show any cytotoxic effect on Hela, HFB, and MCF-7 cell lines. Besides, the pigment did not have any antibacterial properties.
Conclusion: Radioresistant microbial strains are better candidates for microbial pigment production due to their stability and high antioxidant activity. In this study, a whey culture medium was used to reduce the production cost of canthaxanthin. The addition of Krebs intermediaries in the fermentation medium increased the pigment production by Dietzia maris significantly.

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Studies on the production of protein supplements for phenylketonuria (PKU) patients indicate that whey protein is one of the most important protein sources for production of these compounds, owning to its specific combination of amino acids.Whey is considered as one of the most polluting by-product in environment, otherwise, it is an excellent source of functional proteins that can be used in medicine and special diet products. In this study, three different concentrations of whey protein concentrate (WPC) were used as a substrate for three enzymes Flavourzyme^®, Neutrase^®and Protamex^®. Effect of substrate concentration and hydrolysis time were studied on the separation efficiency of phenylalanine using response surface methodology (RSM) design. Phenylalanine was removed from hydrolyzed samples using ultra filtration (UF) and its concentration was measured using HPLC technique. Results of this study showed that samples hydrolyzed by Flavourzyme^® contain the lowest level of phenylalanine. Also, process optimization was done in order to predict the best conditions of hydrolyzing .The best condition in order to remove the maximum phenylalanine from whey proteins was found for the minimum hydrolyzing time and the lowest substrate concentration for all three enzymes.