Control Cheese Research Articles

Potential of histamine-degrading microorganisms and diamine oxidase (DAO) for the reduction of histamine accumulation along the cheese ripening process

Lentilactobacillus parabuchneri is the main bacteria responsible for the accumulation of histamine in cheese. The goal of this study was to assess the efficiency of potential histamine-degrading microbial strains or, alternatively, the action of the diamine oxidase (DAO) enzyme in the reduction of histamine accumulation along the ripening process in cheese. A total of 8 cheese variants of cow milk cheese were manufactured, all of them containing L. parabuchneri Deutsche Sammlung von Mikroorganismen 5987 (except for the negative control cheese variant) along with histamine–degrading strains (Lacticaseibacillus casei 4a and 18b; Lactobacillus delbrueckiisubsp. bulgaricus Colección Española de Cultivos Tipo (CECT) 4005 and Streptococcus salivariussubsp.thermophilus CECT 7207; two commercial yogurt starter cultures; or Debaryomyces hansenii), or DAO enzyme, tested in each cheese variant. Histamine was quantified along 100 days of cheese ripening. All the degrading measures tested significantly reduced the concentration of histamine. The highest degree of degradation was observed in the cheese variant containing D. hansenii, where the histamine content decreased up to 45.32 %. Cheese variants with L. casei, or L. bulgaricus and S. thermophilus strains, also decreased in terms of histamine content by 43.05 % and 42.31 %, respectively. No significant physicochemical changes (weight, pH, water activity, color, or texture) were observed as a consequence of the addition of potential histamine-degrading adjunct cultures or DAO in cheeses. However, the addition of histamine-degrading microorganisms was associated with a particular, not unpleasant aroma. Altogether, these results suggest that the use of certain histamine-degrading microorganisms could be proposed as a suitable measure in order to decrease the amount of histamine accumulated in cheeses.

The Antithrombotic Potential of Bioactive Peptides Induced by Buffalo Milk Probiotic Cheddar Cheese

Cheddar cheese undergoes significant changes resulting in numerous microbiological and biochemical processes called glycolysis, lipolysis, and proteolysis, accountable for a unique texture, aroma, appearance, and taste. Specific bioactive peptides developed during these biochemical reactions impart health benefits. Addition of probiotics boots the development of bioactive peptides in foods. Objective: The current research investigated the therapeutic potential of water-soluble peptides (WSPs) extracts from buffalo milk probiotic Cheddar cheese regarding anti-thrombic facets. Methods: The appropriateness of Buffalo milk for Cheddar manufacturing was assessed by analysing its pH, acidity, fat, protein, and total solids content. Two batches of Cheddar cheese were produced, one having a mixture of Probiotic microorganisms and commercially available mesophilic cheese starter and the second containing only commercially available cheese starters. Both of the cheese batches were analysed for their physicochemical properties. Water-soluble extract of Cheddar cheese samples was analysed for anti-thrombic effects after two-month intervals during ripening. Results: Three concentrations of WSE of buffalo milk cheddar cheese were used to assess the antithrombotic effect during 60, 120, and 180 days of ripening at 4°C. Antithrombotic activity increased with the ripening period for both control and probiotic cheddar cheese samples Conclusion: A significantly increased effect of antithrombotic activity was observed by Probiotic adjunct on control cheddar cheese.

Changes in lipid composition and oxidative status during ripening of Gouda-type cheese as influenced by addition of lavender flower powder

Lipid composition and oxidative stability of Gouda-type cheese, with and without lavender flower powder as a flavouring ingredient, was evaluated during 30 days of maturation at 14 °C. Triacylglycerols represented the main lipid fraction, followed by diacylglycerols, cholesterol, free fatty acids, and monoacylglycerols, and generally, there were no significant changes in their content with ripening time. Saturated fatty acids prevailed in cheese fats, followed by monounsaturated fatty acids and polyunsaturated fatty acids, with palmitic, oleic, myristic, and stearic acids as the main ones. The fatty acid profile was not significantly influenced by ageing, regardless of cheese. Thiobarbituric acid reactive substances increased with ripening time in control cheese and had a V-shape behaviour in lavender cheese, while peroxide value did not change substantially in both cheeses. Supplementation of milk used in Gouda-type cheese making with lavender flower powder (0.5 g L−1) did not significantly interfere with lipolytic and oxidative processes.

Effect of the Addition of Donkey Milk on the Acceptability of Caciotta Cow Cheese.

Simple SummaryCaciotta is a very popular cheese in Italy that can be made with cow, sheep, goat or buffalo milk. In this study, we investigated the effects of donkeys’ milk addition in the production of this cheese, considering a short- and a medium-ripening period. Two batches were considered for cheesemaking: cows’ milk only and cows’ milk with the addition of 5% donkey’s milk. With the longest ripening period, the cheese with donkey milk received the highest ratings for color, aroma, flavor, and overall liking.This study investigated the effects of adding donkey milk in cheesemaking on the acceptability of a Caciotta cow cheese after 10 and 45 days of ripening. The cheeses produced were: a control cheese with cow’s milk only and experimental cheese with the addition of 5% donkey’s milk. The acceptability of Caciotta was determined by the judgement of 80 habitual cheese consumers. The acceptability of the Caciotta cheese was significantly influenced by the addition of donkey milk, with the exception of the texture parameter. At a ripening time of 10 days, the control cheese scored significantly higher than the experimental cheese for aroma, flavor and overall liking; conversely, at the longest time, the experimental cheese had significantly higher scores for color, aroma, flavor, and overall liking. Our results confirm that the use of donkey milk in cheesemaking can improve cheese acceptability. In addition, the known benefits of using donkey milk in cheesemaking, such as the reduction of blowing defects and the probiotic properties, could increase interest in innovative products among both processors and consumers. Processors could reduce, if not eliminate, the use of additives in cheesemaking, while cheese could also appeal to consumers of probiotic and fermented products.

The technology of manufacturing cheese from cow's milk using a starter culture Enteroplan

The article presents data on the use in the cheese-making technology starter culture “Enteroplan”, which includes strains of lactic acid bacteria isolated from traditional Carpathian cheese, particularly L. lactis, Lb. plantarum, E. durans in the ratio 50 : 40 : 10. The microflora of traditional dairy products, particularly cheese, has evolved through time and is unique. It is essential to reproduce and preserve such a microbiome in cheese making. A change in the technology was the use of cow's milk by introducing our starter culture, “Enteroplan”. For the manufacturing of bryndza, cow's milk was chosen, which satisfied regulatory documentation criteria in terms of organoleptic characteristics, physicochemical properties, and cheese suitability. According to organoleptic parameters, the manufactured prototype of cheese with starter culture “Enteroplan” had a pronounced, rich creamy-cheese taste and smell; its consistency was homogeneous, plastic, moderately dense, whereas the control cheese made with RSF had a less pronounced taste and smell, and its consistency was homogeneous, plastic, and moderately fragile. No significant discrepancies were found in other organoleptic indicators. According to the results of the scoring of the cheese, the prototype received 3 points more. The taste, odor, and consistency of the test sample were examined above compared to the control sample. During the 20-day maturation period of the cheese, the number of lactic acid bacteria was relatively high, ranging in the control sample from (6.6 ± 0.28)×105 to (2.5 ± 0.23)×105 CFU/g and in the experimental sample from (8.1 ± 0.30)×105 to (6.1 ± 0.18)×105 CFU/g. Pathogenic microflora, mold, and yeast-like fungi were not detected during the storage of the manufactured cheese samples.

COMPARISON OF ANTIFUNGAL PROPERTIES OF LACTOBACILLUS RHAMNOSUS AND LACTOBACILLUS REUTERI WITH POTASSIUM SORBATE IN THE IRANIAN UF-FETA CHEESE

This study was aimed to compare antifungal properties of two lactobacilli strains with potassium sorbate in cheese. In this regard, the effect of 10-fold cell-free extract of Lactobacillus rhamnosus РТСС 1637 and Lactobacillus reuteri РТСС 1655 was studied on the growth of mold and yeast in the Iranian UF-Feta Cheese during a 60-day ripening period at 4 ℃. Additionally, the antifungal effect of potassium sorbate (300 and 500 ppm) and mixture of potassium sorbate and cell-free extract of tested bacteria were evaluated. The results showed that yeast and mold growth was occurred in both control and treated chesses, however, after 30 days storage, mold and yeast count was significantly lower in the cell free supernatant-treated UF-Feta cheese in comparison to the control cheese. Addition of potassium sorbate, as expected, significantly reduced mold and yeast growth in UF-Feta cheese during ripening period than control. On the other hand the result showed that mixture of probiotic extract and potassium sorbate had more efficiency in mold and yeast growth reduction than when the sorbate potassium was used alone. The highest fungal growth inhibition was achieved by application of 2 mL cell-free extract of L. reuteri CCTP 1655 along with 500 ppm potassium sorbate. Generally, it could be concluded that cell-free supernatant of tested bacteria has potential for use as bio preservatives in cheese and although studied probiotic extracts are not as effective as sorbate potassium in preventing fungi and yeast growth, they can be useful in reduction of yeast and mold growth.

Gas production by Paucilactobacillus wasatchensis WDCO4 is increased in Cheddar cheese containing sodium gluconate

Paucilactobacillus wasatchensis can use gluconate (GLCN) as well as galactose as an energy source and because sodium GLCN can be added during salting of Cheddar cheese to reduce calcium lactate crystal formation, our primary objective was to determine if the presence of GLCN in cheese is another risk factor for unwanted gas production leading to slits in cheese. A secondary objective was to calculate the amount of CO2 produced during storage and to relate this to the amount of gas-forming substrate that was utilized. Ribose was added to promote growth of Pa. wasatchensis WDC04 (P.waWDC04) to high numbers during storage. Cheddar cheese was made with lactococcal starter culture with addition of P.waWDC04 on 3 separate occasions. After milling, the curd was divided into six 10-kg portions. To the curd was added (A) salt, or salt plus (B) 0.5% galactose + 0.5% ribose (similar to previous studies), (C) 1% sodium GLCN, (D) 1% sodium GLCN + 0.5% ribose, (E) 2% sodium GLCN, (F) 2% sodium GLCN + 0.5% ribose. A vat of cheese without added P.waWDC04 was made using the same milk and a block of cheese used as an additional control. Cheeses were cut into 900-g pieces, vacuum packaged and stored at 12°C for 16 wk. Each month the bags were examined for gas production and cheese sampled and tested for lactose, galactose and GLCN content, and microbial numbers. In the control cheese, P.waWDC04 remained undetected (i.e., <104 cfu/g), whereas in cheeses A, C, and E it increased to 107 cfu/g, and when ribose was included with salting (cheeses B, D, and F) increased to 108 cfu/g. The amount of gas (measured as headspace height or calculated as mmoles of CO2) during 16 wk storage was increased by adding P.waWDC04 into the milk, and by adding galactose or GLCN to the curd. Galactose levels in cheese B were depleted by 12 wk while no other cheeses had residual galactose. Except for cheese D, the other cheeses with GLCN added (C, E and F) showed little decline in GLCN levels until wk 12, even though gas was being produced starting at wk 4. Based on calculations of CO2 in headspace plus CO2 dissolved in cheese, galactose and GLCN added to cheese curd only accounted for about half of total gas production. It is proposed that CO2 was also produced by decarboxylation of amino acids. Although P.waWDC04 does not have all the genes for complete conversion and decarboxylation of the amino acids in cheese, this can be achieved in conjunction with starter culture lactococcal. Adding GLCN to curd can now be considered another confirmed risk factor for unwanted gas production during storage of Cheddar cheese that can lead to slits and cracks in cheese. Putative risk factors now include having a community of bacteria in cheese leading to decarboxylation of amino acids and release of CO2 as well autolysis of the starter culture that would provide a supply of ribose that can promote growth of Pa. wasatchensis.

Evaluation of Physicochemical Properties and Sensory Attributes of Galactooligosaccharides (GOS) Enriched Cottage Cheese

Galactooligosaccharides (GOS) mimic the role of dietary fibres and are known to offer several health benefits, especially those relating to heart and gastrointestinal health. Glycosidation of lactose in milk can be utilized to produce GOS in cottage cheese. The current study was conducted to evaluate the sensory as well as physicochemical properties of GOS containing cottage cheese. For this purpose, transgalactosylated milk was used to obtain casein after it was curdled using citric acid. Subsequently, the sensory evaluation of organoleptic properties was done by ten panellists on the 0, 4th, 8th, and 12th day of storage. The sensory characteristics during the shelf-life study did not show a significant difference. The prebiotic cheese was sweeter and softer as compared to the control cheese. Additionally, the prebiotic cheese was ranked higher in the overall sensory characteristics score than the control cheese. Based on the findings, we suggest that GOS containing cheese as well as other food products should be commercially produced since they would be a valuable healthy addition to the diet.

Effect of Fortification with Mushroom Polysaccharide β-Glucan on the Quality of Ovine Soft Spreadable Cheese.

In the present work, a fresh spreadable cheese from ovine milk with or without (control) fortification with β-glucan was manufactured. β-Glucan was extracted from the mushroom Pleurotus ostreatus and its concentration in the cheese was 0.4% (w/w). The composition, biochemical, and sensory properties of the cheeses during 21 days of storage were determined. At the end of storage, cheese fortified with beta-glucan had 75.26% moisture content, 10.30% fat, 1.71% salt, and 8.50% protein. Generally, the addition of β-glucan at this concentration did not significantly affect the composition, color, and viscosity measurements or the level of proteolysis and lipolysis and the antioxidant activity of the cheeses. However, cheese fortified with β-glucan showed a higher moisture content than control cheese on the 1st and 21st day of storage while the levels of proteolysis and the sensory properties of the cheeses were unaffected. During the sensory evaluation, panelists evaluated cheese with β-glucan with higher scores regarding the flavor characteristic compared to control cheese. The major free fatty acid was acetic acid in both cheeses and its concentration was higher in cheese with β-glucan. The results of the present study could be used by the dairy industry for manufacturing new products with improved health benefits.

Innovative vegetables-processed cheese: II. high nutritional and functional attributes

Background: Foods not only aim to satisfy hunger and provide for essential nutritional needs, but they also improve the consumers' general health and prevent diseases related to nutrition. Nowadays, functional foods have seen rapid growth in the market driven by technological innovation and new product development. Our recent study produced a novel processed cheese using vegetables mixture that had a highly physicochemical composition and rheological and sensory characteristics.Methods: This study was conducted to improve the nutritional and functional qualities of processed cheese using several vegetables (flavored-processed cheese, FPC) (mushrooms, dill, leeks, parsley, celery, green peas, green beans, squash, potatoes, and carrots) with ratios of 2.5, 5, 7.5, and 10%.Results: Our data on nutritional values for FPC samples contain extra micro and macro-nutrient components, such as vitamins, minerals, antioxidants, amino acids, and unsaturated fatty acids, compared to the control cheese. Adding the vegetable mixture was accepted by the consumers and can contribute to the production and development of a new and safe type of processed cheese that has an excellent nutritional value, functional properties, and overall acceptability. Ratios of 5% and 7.5% were observed as the best samples.Conclusion: We recommend that vegetables should be used as a natural food additive for technological purposes. These are necessary sources of human health-promotion by nutritional and functional food properties of various dairy products.Keywords: Processed cheese, vegetables, nutritional values, amino acids, fatty acids, minerals, vitamins, and antioxidants

Microbial and chemical composition of Cheddar cheese supplemented with prebiotics from pasteurized milk to aging

Microbial and chemical properties of cheese is crucial in the dairy industry to understand their effects on cheese quality. Microorganisms within this fat, protein, and water matrix are largely responsible for physiochemical characteristics and associated quality. Prebiotics can be used as an energy source for lactic acid bacteria in cheese by altering the microbial community and provide the potential for value-added foods, with a more stable probiotic population. This research focuses on the addition of fructooligosaccharides (FOS) or inulin to the Cheddar cheese-making process to evaluate the effects on microbial and physicochemical composition changes. Laboratory-scale Cheddar cheese produced in 2 replicates was supplemented with 0 (control), 0.5, 1.0, and 2.0% (wt/wt) of FOS or inulin using 18 L of commercially pasteurized milk. A total of 210 samples (15 samples per replicate of each treatment) were collected from cheese-making procedure and aging period. Analysis for each sample were performed for quantitative analysis of chemical and microbial composition. The prevalence of lactic acid bacteria (log cfu/g) in Cheddar cheese supplemented with FOS (6.34 ± 0.11 and 8.99 ± 0.46; ± standard deviation) or inulin (6.02 ± 0.79 and 9.08 ± 1.00) was significantly higher than the control (5.84 ± 0.27 and 8.48 ± 0.06) in whey and curd, respectively. Fructooligosaccharides supplemented cheeses showed similar chemical properties to the control cheese, whereas inulin-supplemented cheeses exhibited a significantly higher moisture content than FOS and the control groups. Streptococcus and Lactococcus were predominant in all cheeses and 2% inulin and 2% FOS-supplemented cheeses possessed significant amounts of nonstarter lactic acid bacteria found to be an unidentified group of Lactobacillaceae, which emerged after 90 d of aging. In conclusion, this study demonstrates that prebiotic supplementation of Cheddar cheese results in differing microbial and chemical characteristics.

γ-Aminobutyric acid production and antioxidant activities in fresh cheese by Lactobacillus plantarum L10-11

This study aimed to evaluate the γ-aminobutyric acid (GABA) production and antioxidant activity during fresh cheese processing with single and co-fermentation processes of the high-GABA producing strain, Lactobacillus plantarum L10-11. For a mini-batch of fresh cheese, milk with 0.1% monosodium glutamate was fermented for 18 h and GABA production was monitored by thin layer chromatography and ion chromatography. GABA could be detected in co-L10-11 at 12 h of fermentation and at greater amounts after 18 h. The 18 h fermented milk of co-L10-11 and single-L10-11 contained GABA at 11.30 and 1.21 mg/100 mL, respectively, while GABA was not detected in the control. After whey separation, GABA remained in the cheese curd portion, resulting in 14.91 mg/100 g being found in the co-L10-11 cheese curd. ABTS antioxidant and metal chelating activities significantly increased during 18 h of fermentation and were retained in the cheese curd in the range of 783.11-922.00 μmol TE/kg and 216.71-266.98 μmol EDTA equivalents/kg cheese, respectively. Moreover, there were no significant difference in the textural characteristic between co-L10-11 and the control cheese curd. These results suggested that Lb plantarum L10-11 could be exploited as adjunct to improve health-promoting effects of the GABA in fresh cheese.

Impact of different starter cultures and Lactobacillus helveticus on volatile components, chemical and sensory properties of pasta filata cheese

L.helveticus is known to follow mainly similar metabolic pathways to contribute to cheese flavor with S. thermophilus and L. delbrueckii subsp. bulgaricus. In this study, the flavor contributions of commercial S. thermophilus starter cultures of different brands and L. helveticus adjunct culture to pasta filata type fresh Kashar cheese were investigated. L. helveticus affected the buttery aroma components of fresh Kashar cheese and resulted in low diacetyl content. In addition, acetaldehyde and other aroma components of L. helveticus added cheese was found to be higher than control and modified control cheeses. On the other hand, the modified control sample containing S. thermophilus from Danisco instead of Chr-Hansen in the control was closer to the control sample in terms of volatile profile. As the shelf-life progressed, the contribution of alcohols and hydrocarbons to volatile components decreased, while the contribution of ketones, which was the dominant group, increased in all products. When the proteolysis and lipolysis levels were examined, the control sample differed from the other two cheese samples with its high proteolysis and lipolysis rate. In summary, the rates of increase in water-soluble nitrogen and free fatty acid contents in 8 weeks of storage (from 18 to 72 days) were determined as 61% and 47%, respectively, in the control Kashar cheese, while it was 39% and 27% in the L. helveticus added sample, and 37% and 28% in the modified control sample. Finally, the sensory scores revealed that cheese flavor and texture preferences could be increased with the addition of L. helveticus.

The Effect of the Liposomal Encapsulated Saffron Extract on the Physicochemical Properties of a Functional Ricotta Cheese.

In this study, the encapsulation of saffron extract (SE) was examined at four various concentrations of soy lecithin (0.5%–4% w/v) and constant concentration of SE (0.25% w/v). Particle size and zeta potential of liposomes were in the range of 155.9–208.1 nm and −34.6–43.4 mV, respectively. Encapsulation efficiency was in the range of 50.73%–67.02%, with the stability of nanoliposomes in all treatments being >90%. Encapsulated SE (2% lecithin) was added to ricotta cheese at different concentrations (0%, 0.125%, 1%, and 2% w/v), and physicochemical and textural properties of the cheese were examined. Lecithin concentration significantly (p ≤ 0.05) affected the particle size, zeta potential, stability, and encapsulation efficiency of the manufactured liposomes. In terms of chemical composition and color of the functional cheese, the highest difference was observed between the control cheese and the cheese enriched with 2% liposomal encapsulated SE. Hardness and chewiness increased significantly (p ≤ 0.05) in the cheeses containing encapsulated SE compared to the control cheese. However, there was no significant difference in the case of adhesiveness, cohesiveness, and gumminess among different cheeses. Overall, based on the findings of this research, liposomal encapsulation was an efficient method for the delivery of SE in ricotta cheese as a novel functional food.

Spirulina platensis Extract Nanoliposomes: Preparation, Characterization, and Application to White Cheese.

Ultrafiltration cheese is produced in large scale from treated pasteurized milk with mesophilic starter, and to expand its shelf life, preservatives addition is needed. The purpose of the present study was preparation of encapsulate Spirulina platensis algae nanoliposomes to evaluate the characteristics of the nanoliposomes loaded with Spirulina extract (SE-NLs). In addition, the chemical and microbiological properties of white cheese produced with SE-NLs were studied. Nanoliposomes are composed of lecithin and cholesterol, used for the encapsulation of SE. The SE-NLs were prepared using the thin-layer hydration method. The characteristics of produced SE-NLs including particle size, zeta potential, morphology, and the encapsulation efficiency were studied during 4 weeks in different storage conditions (4°C and 25°C). In addition, the effect of SE and SE-NLs on the chemical and microbiological properties of white cheese was evaluated during 60 days of ripening. The results showed that the nanoliposomes loaded with 3 mg/g of SE had the optimum formulation due to the higher EE, smaller particle size, and higher negatively charged zeta potential. The quality of the produced nanoliposomes decreased by increasing the time of storage, but the SE-NLs stored at 4°C were more stable and possessed higher EE and smaller particle sizes. While the chemical composition of the cheeses manufactured by the nanoliposome loaded with 3 mg/g SE-NLs were comparable to that of control cheese at 60 days of ripening, it showed a significant inhibitory effect on Staphylococcus aureus and Listeria monocytogenes after 30 days. The utilization of SE-NLs can be considered a natural antimicrobial and an alternative to the use of synthetic preservatives in the production of white cheese. Nanoliposomes of Spirulina platensis extracts were prepared. Ultrafiltration white cheese prepared by nanoliposomes then was evaluated.

Conversion of milk lactose to galacto-oligosaccharides by enzymes to produce prebiotic enriched cheese

In this study, lactose in milk is converted to galacto-oligosaccharides (GOS) using β-gal from Kluveromyces lactis. Trans-galactosylation was done by adding 1 mL of β-gal in 1L milk at 42°C for 2 hours with continuous agitation. Subsequently, the cheese prepared from the GOS enriched milk and control milk were compared for the physico-chemical and organoleptic properties. The chemical composition of prebiotic cheese exhibited non-significant differences for the fat, protein, moisture and ash, whereas a significantly lower level of lactose (56.25%) was observed as compared to control cheese. Organoleptic evaluation showed that the prebiotic cheese has a similar appearance and overall acceptability as does the control cheese except for taste and texture which were improved by trans-glycosylation.

Influence of GABA-producing yeasts on cheese quality, GABA content, and the volatilome

To explore the influence of γ-Aminobutyric acid (GABA)-producing yeast on the quality of cheese, Pichia kudriavzevii 1–21, Kluyveromyces marxianus B13-5, Saccharomyces cerevisiae DL6-20, Kluyveromyces lactis DY1-10, and a commercial starter were used to make cheese, with only the commercial starter used as a control. The results showed that K. marxianus B13-5 produced cheese had the highest GABA content (up to 489 mg/kg) and a relatively good texture, and K. lactis DY1-10 increased the production of amino acids. Principal component analysis and orthogonal partial least squares discrimination analysis were performed to distinguish the different substances in the yeast-produced cheeses from those of the control cheese. Headspace solid phase microextraction-gas chromatography-mass spectrometry of aroma compounds demonstrated that the four cheeses had strong fruity, apple, and pineapple aromas, and the yeasts all produced butanoic acid, ethyl ester, acetic acid ethyl ester, hexanoic acid, ethyl ester, and octanoic acid, ethyl ester. Compared with the control group, the different substances in the yeast-produced cheeses were 2-heptanol, 1-propanol, 2-methyl-, benzene ethanol, isoamyl alcohol; propanoic acid, 2-methyl-, acetic acid; 2-butanone; 3-hydroxy-, octanoic acid ethyl ester, and acetic acid ethyl ester. Cheese made by GABA-producing yeast could have potential probiotic effects and improved flavor.

Pomegranate Byproduct Extracts as Ingredients for Producing Experimental Cheese with Enhanced Microbiological, Functional, and Physical Characteristics

Pomegranate peel and mesocarp, considered as wastes of fruit processing, are rich sources of beneficial phytochemicals, including hydrolyzable tannins and flavonoids, with proven antimicrobial and antioxidant activity, which can be employed for improving the overall quality of food products. In the present study, extracts from pomegranate peel (PPW) and mesocarp (PMW) were obtained through a water extraction method and evaluated for in vitro antimicrobial activity and polyphenol content. The two extracts were then added during the cheese-making process in order to create a new functional cheese with improved microbiological and physico-chemical characteristics. Antimicrobial in vitro assays evidenced a substantial efficacy of both extracts against Staphylococcus aureus, which often causes staphylococcal food poisoning outbreaks linked to the consumption of raw milk cheeses and artisanal cheeses. For this reason, a simulated cheese contamination was carried out in order to assess if pomegranate extracts can exert antimicrobial activity towards this pathogen even when incorporated into the cheese matrix. Milk enriched with pomegranate extracts (PPW and PMW) was used to produce two different experimental cheeses, which were then evaluated for yield, polyphenol content, and microbiological as well as physico-chemical traits throughout the refrigerated storage. Despite the low concentration of the extracts, the treated cheeses showed an increase in firmness and a slight decrease in S. aureus counts, of more than one log unit in comparison to the control cheese, for up to 12 d of cold storage. Such results support the reuse of agro-food byproducts, in substitution to chemical food preservatives, as the key to a circular economy.

Improving Low-Fat Soft Cheese Quality Properties Made From Reconstituted Skim Milk By Using Whey Protein Concentrate as A fat Replacer

This study was conducted to determine the effect of using whey protein concentrate (WPC) as a fat replacer and its role in improving the physicochemical, rheological, and sensory properties of low-fat soft cheese by adding four different ratios of (WPC) as (1.0,1.5,2.0,2.5) % to reconstituted bovine skim milk in four treatments (W2, W3, W4, W5)respectively, besides control cheese treatment (W1)which was made of whole bovine milk. The chemical tests included the percentage of moisture, protein, fat, lactose, and ash. The physical tests included the percentage of total acidity, pH, springiness, and compression ability besides cheese yield percentage, total energy, and sensory evaluation after cheese making and throughout the 14 days of storage time at (5±1)°C. Results showed that all (WPC) treatments have high moisture percentage compared to the control treatment, though all the treatments had a decrease in moisture values with storage. Results also showed a decrease in fat content for all the skim milk treatments with (WPC) addition. Lactose percentages were converged in all treatments. The results also showed an increase in total acidity and a decrease in pH for the (WPC) addition treatments. Microbiological results showed increased total count for the (WPC) addition treatments compared with the control. Furthermore, the results showed that adding (WPC) led to improving the springiness and compression ability and increased the cheese yield. On the other hand, it decreased the cheese energy compared to control. Sensory properties were improved by added WPC.

Increasing the proportion of homogenised fat in cheese milk: Effect on cheese-making properties

Adjusting the proportion of homogenised fat in cheese milk is proposed as a means to better control cheese yield and composition. Homogenised milk or cream was used to standardise cheese milk with variable proportions of homogenised fat. Fat globules in homogenised milk and cream were analysed for size, protein load and zeta potential. The coagulation properties of cheese milks were measured, and the composition and rheological properties of model curds were determined. Fat globules in homogenised milk were significantly smaller with a higher protein load than those in homogenised cream (P < 0.05). Curd moisture content, fat retention, actual and moisture-adjusted yields increased with the proportion of homogenised fat in cheese milk, while curd storage modulus decreased. The intensity of these effects was higher in milk than in cream when homogenisation was applied. Adjusting the proportion of homogenised fat in cheese milk is a convenient approach to increase yield and control cheese composition.