Cheese Production Process Research Articles

Loads of Coliforms and Fecal Coliforms and Characterization of Thermotolerant Escherichia coli in Fresh Raw Milk Cheese.

The aim of this study was to assess the hygienic status of raw milk cheese and determine the trends of virulence and antimicrobial resistance in thermotolerant Escherichia coli. Two hundred samples of karish, a popular Egyptian fresh raw milk cheese, were analyzed for coliforms and fecal coliforms using a standard most probable number (MPN) technique. Overall, 85% of samples were unsuitable for consumption, as they exceeded Egyptian standards for coliforms (10 MPN/g), and 65% of samples exhibited coliforms at 44.5 °C. Of 150 recovered thermotolerant strains, 140 (93.3%) were identified as E. coli. Importantly, one Shiga toxin-producing E. coli (STEC) strain carrying a striking virulence pattern, stx1−, stx2+, eae−, was detected. Eleven strains (7.8%, 11/140) showed resistance to third-generation cephalosporins. Antibiotic resistance genes included blaSHV, blaCTX-M, qnrS, tet(A), and tet(B), which were present in 4.3%, 2.8%, 0.71%, 2.1%, and 0.71% of isolates, respectively. In conclusion, this study indicated that hygienic-sanitary failures occurred throughout the production process of most retail karish cheese. Furthermore, our findings emphasize the need for adopting third-generation cephalosporin-resistant E. coli as an indicator for monitoring antimicrobial resistance in raw milk cheese to identify the potential public health burden associated with its consumption.

The effect of using microencapsulated pro and prebiotics on the aromatic compounds and sensorial properties of synbiotic goat cheese

In this study, synbiotic goat cheese was obtained by adding free and microencapsulated probiotic bacteria and prebiotics to goat milk. Three types of microcapsules containing Lacticaseibacillus casei and Bifidobacterium longum, fructooligosaccharide and inulin were obtained and these microcapsules were added during the cheese production process. In synbiotic microcapsule added goat cheese, changes in volatile aroma substances and sensory properties during storage (180 days at +4 °C) and the effect of microencapsulation on these changes were determined. Most of the aroma compounds determined during storage in goat cheeses are alcohols and acids, and it is seen that the use of probiotic supplement culture increases the number of aroma compounds in cheese. It was determined that sensory properties of goat cheese are not affected by the use of probiotic supplements, prebiotics, and microencapsulation and was appreciated by the panelists.

Some properties of milk used in the production of Diyarbakır Örgü cheese and evaluation of the cheese production process

Amaç: Bu çalışma, geleneksel Diyarbakır Örgü peynirinin üretiminde kullanılan sütün bileşimi, asitliği ve toplam aerobik mezofilik bakteri yükünün araştırılmasının yanında, söz konusu peynirin geleneksel üretim prosesinin tespit edilmesi amacıyla yapılmıştır.Materyal ve Yöntem: Geleneksel Diyarbakır Örgü peynirinin üretildiği 8 adet küçük ölçekli süt işletmesinde Nisan-Mayıs aylarında, her bir işletmeden 4 defa çiğ süt örneği (8x400 mL) alınmıştır. Diğer taraftan, 4 işletmede peynirin üretim prosesi takip edilmiştir. Çiğ süt örneklerinin bileşim (yağ, protein, laktoz, KM, kül) analizleri Funke Gerber cihazı (Lactostar, 3510-070702, Almanya) ile, pH ölçümleri ise dijital pH metre (WTW 330i, Germany) ile yapılmıştır. Soğuk zincir muhafaza edilerek laboratuvara ulaştırılan süt örneklerinin 10-8’e kadar dilüsyonları hazırlanmıştır. Ardından dökme plak yöntemi ile PCA besiyerine ekim yapılmış, 30 °C’de 48 saat inkübasyon sonrası toplam aerobik mezofilik bakteri sayımı yapılmıştır. Peynirin tüm üretim aşamalarında sıcaklık, asitlik ve tuz değerleri ile uygulanan her bir işlemin süresi kayıt altına alınmış ve bu veriler doğrultusunda Diyarbakır Örgü peynirinin üretim prosesi oluşturulmuştur. Çalışmaya ait veriler tek yönlü ANOVA ile analiz edilmiş, önemli bulunan ortalamalar arasındaki farklılık Tukey çoklu karşılaştırma testi ile belirlenmiştir.Araştırma Bulguları: Peynir üretiminde kullanılan çiğ sütün ortalama kurumadde, yağ, protein, laktoz ve kül oranları ile titrasyon asitliği, pH değeri ve toplam aerobik mezofilik bakteri sayısı sırasıyla %14.28, %4.37, %4.41, %4.63, %0.87, 11.55 SH, pH 6.54 ve 7.51 log kob mL-1 olarak tespit edilmiştir.Sonuç: Yapılan ölçüm ve gözlemlerde, peynir üretiminin tamamen ustalık becerileri doğrultusunda gerçekleştirildiği anlaşılmıştır. Bu nedenle iyi üretim uygulamaları bağlamında, peynirin üretiminde kullanılan sütün standardize edilmesi, sütün mayalanması, telemenin fermantasyonu ile haşlanması ve tuzlama işlemleri gibi önemli proses aşamaları değerlendirilmeli ve gerekli iyileştirmeler yapılmalıdır.

A Study on the Feasibility of Anaerobic Co-Digestion of Raw Cheese Whey with Coffee Pulp Residues

In this paper, a study on the feasibility of the treatment of raw cheese whey by anaerobic co-digestion using coffee pulp residues as a co-substrate is presented. It considers raw whey generated in artisanal cheese markers, which is generally not treated, thus causing environmental pollution problems. An experimental design was carried out evaluating the effect of pH and the substrate ratio on methane production at 35 °C (i.e., mesophilic conditions). The interaction of the parameters on the co-substrate degradation and the methane production was analyzed using a response surface analysis. Furthermore, two kinetic models were proposed (first order and modified Gompertz models) to determine the dynamic profiles of methane yield. The results show that co-digestion of the raw whey is favored at pH = 6, reaching a maximum yield of 71.54 mLCH4 gVSrem−1 (31.5% VS removed) for raw cheese whey and coffee pulp ratio of 1 gVSwhey gVSCoffe−1. The proposed kinetic models successfully fit the experimental methane production data, the Gompertz model being the one that showed the best fit. Then, the results show that anaerobic co-digestion can be used to reduce the environmental impact of raw whey. Likewise, the methane obtained can be integrated into the cheese production process, which could contribute to reducing the cost per energy consumption.

An Integrated Approach for the Valorization of Cheese Whey.

Taking into account the large amount of whey that is produced during the cheese production process and the constant demand by society for more sustainable processes, in accordance with Sustainable Development Goals (SDGs) and the circular economy concept, it is necessary to adapt two-unit operations into a single process, allowing us to not only valorize a part of the whey but the whole process, which is known as bioprocess integration. In this sense, the adaptation of different processes, for example, physicochemical (micro, ultra and nanofiltration) and fermentation, that are commonly used to obtain proteins, lactose and other compounds with different activities (antioxidant, antifungal, etc.) could be integrated to achieve a complete recovery of the cheese whey. Likewise, keeping in mind that one of the main drawbacks of cheese whey is the great microbial load, some innovative processing technologies, such as high hydrostatic pressures, electrotechnologies and ultrasound, can allow both the development of new foods from whey as well as the improvement of the nutritional and organoleptic properties of the final products prepared with cheese, and thus reducing the microbial load and obtaining a safe product could be incorporated in the cheese whey valorization process.

The physical characteristics of cheese made of milk, colostrum and both during the ripening

This study aimed to understand the physical characteristics of cheese made of cow milk, colostrum, and milk+colostrum ripened for 20 days. Two factors in this study were cheese made of three materials: A (100% cow milk), B (50% cow milk + 50% colostrum) and C (100% colostrum), and ripening time, i.e. 0, 10, and 20 days. The process of cheese production started by heating the raw material, followed by decreasing the temperature, incorporating kefir as the starter. The next step was and the rennet and re-incubate the mixture for one hour until the fluid became solid granules, then the granules were filtered and pressed. The cheese was stored at a low temperature (4-8oC) according to each treatment. Each combination was repeated three times. The physical properties of cheese examined in this study were color, texture, pH, and microstructure. The result showed that the raw materials of cheese would produce different cheese colours in terms of lightness (L*), yellowness (b*), and whiteness index (WI) as well as cheese texture (hardness and gumminess). Also, ripening time would affect the hardness, springiness gumminess, chewiness, L*, a*, and WI of cheese. Colostrum added in cheesemaking has increased both yellowness and cavities in the microstructure.

Contribution to the Process Development for Lactulose Production through Complete Valorization of Whey Permeate by Using Electro-Activation Technology Versus a Chemical Isomerization Process.

Whey permeate (WP) is a co-product of a cheese or casein production process that is regarded as an environmental pollutant because of its high organic load and is creating a major disposal problem for the dairy industry. However, it can be used as a suitable substrate to meet the increasing demand of producing a prebiotic lactulose through the isomerization of lactose present in the WP under adequate alkaline conditions. The goal of this study was to produce lactulose in situ of WP using electro-activation (EA) technology and compare the productivity of EA with conventional chemical isomerization at potassium hydroxide (KOH)-equivalent solution alkalinity in the feed medium. Electro-isomerization was conducted under different current intensities of 300, 600, and 900 mA for 60 min of EA with a 5 min sampling interval using 6, 12, and 18% (w/v) WP solutions. Chemical isomerization was carried out at the KOH-equivalent solution alkalinity to that measured in the EA solution at each 5 min interval using KOH powder as a catalyst. The outcomes of this study revealed that the production of lactulose using the EA approach was current intensity-, WP concentration-, and reaction time-dependent and produced the highest lactulose yield of 36.98% at 50 min of EA-time under 900 mA current intensity using 6% WP as a feed solution, whereas a maximum lactulose yield of 25.47% was achieved by the chemical isomerization at the solution alkalinity corresponding to that of the EA under 900 mA current intensity at 50 min in the 6% WP solution. Furthermore, a greater yield of lactulose was obtained using the EA technique for all reaction conditions compared to the chemical process at the equivalent solution alkalinity. Therefore, the results of this work suggest that the EA can be an emergent sustainable technology for achieving dual objectives of prebiotic lactulose production and concurrent valorization of WP using it as a feed medium.

Development of a functional whey cheese (ricotta) enriched in phytosterols: Evaluation of the suitability of whey cheese matrix and processing for phytosterols supplementation

This study aims to evaluate the suitability of whey cheese (ricotta) and whey cheese production process for phytosterols-enrichment. Therefore, the phytosterols stability of ricotta cheese was assessed during cheese processing (85 °C for 60 min) and storage (4 °C for 4 weeks). Given the novelty of the food matrix used, it was necessary to develop an innovative analytical method for sterols determination in enriched ricotta cheese. The developed HPLC-DAD method showed good linearity (R2 ≥ 0.9956) and reproducibility (0.4–7.6%), while extraction recoveries ranged between 83.7% and 84.6%. Phytosterols showed a good heat-stability in ricotta cheese matrix during cheese processing (87.0–89.7) %. Moreover, the functional cheese showed a homogeneous phytosterols distribution and maintained its potential bioactivity during its shelf-life since no significant variation of phytosterols levels was observed during storage (0.83 ± 0.03) g/100 g.

Virulence factors and antimicrobial resistance of Staphylococcus aureus isolated from the production process of Minas artisanal cheese from the region of Campo das Vertentes, Brazil

Staphylococcus aureus is one of the main pathogens found in cheeses produced with raw milk, including Minas artisanal cheese from Brazil. However, information about S. aureus isolated from artisanal cheeses and its sources of production in small-scale dairies is very limited. We aimed to characterize the virulence factors of S. aureus isolated from raw milk, endogenous starter culture, Minas artisanal cheese, and cheese handlers from the region of Campo das Vertentes, Minas Gerais, Brazil. We identified the staphylococcal isolates by MALDI-TOF mass spectrometry. We evaluated biofilm production on Congo red agar and polystyrene plates. We used PCR to detect icaA, icaB, icaC, sea, seb, sec, sed, see, tsst-1, agr, and mecA. We evaluated the expression of staphylococcal toxin genes in PCR-positive staphylococcal isolates using quantitative reverse-transcription PCR, and we evaluated the production of these toxins and their hemolytic activity in vitro. We also evaluated the antimicrobial resistance profile of the staphylococcal isolates. For statistical analysis, we used cluster analysis, χ2 tests, and correspondence tests. We analyzed 76 staphylococcal isolates. According to PCR, 18.42, 18.42, 2.63, and 77.63% were positive for sea, tsst-1, sec, and agr, respectively. We found low expression of staphylococcal toxin genes according to quantitative reverse-transcription PCR, and only 2 staphylococcal isolates produced toxic shock syndrome toxins. A total of 43 staphylococcal isolates (56.58%) had hemolytic activity; 53 were biofilm-forming on Congo red agar (69.73%), and 62 on polystyrene plates (81.58%). None of the staphylococcal isolates expressed the mecA gene, and none presented a multi-drug resistance pattern. The highest resistance was observed for penicillin G (67.11%) in 51 isolates and for tetracycline (27.63%) in 21 isolates. The staphylococcal isolates we evaluated had toxigenic potential, with a higher prevalence of sea and tsst-1. Biofilm production was the main virulence factor of the studied bacteria. Six clusters were formed whose distribution frequencies differed for hemolytic activity, biofilm formation (qualitative and quantitative analyses), and resistance to penicillin, tetracycline, and erythromycin. These findings emphasize the need for effective measures to prevent staphylococcal food poisoning by limiting S. aureus growth and enterotoxin formation throughout the food production chain and the final product.

Use of ultra-high-temperature processing of raw milk to improve cheese quality

The increase in natural cheese production has brought issues related to ensuring the production of high-quality competitive products to the fore. The development of the cheese market requires constant improvement of the existing methods of production and the search for new technological solutions, which will allow us to counterbalance the low quality of raw materials, which is currently a serious problem for domestic cheese production. A promising method of realising the benefits of high-temperature (HT) and ultra-high-temperature (UHT) milk processing in cheese making is the development of new types of cheese with a high moisture content; however, there are very few publications that discuss these approaches. The development of advanced technologies for the production of low-temperature second-degree solid cheeses with the use of HT and UHT processing, related to the improvement of the technological process and the equipment and technological scheme of production of solid cheeses. The main direction of the development of cheese production at the present stage is the improvement of existing technological processes, the development of resource-saving technologies and the improvement of the natural solid rennet cheese quality. The results of our research, related to the study of the composition and safety of milk raw materials, the impact of various technological factors on the cheese production process and the quality of the products obtained, are the basis for our resource-saving technology for the production of solid rennet cheese.

CHARACTERIZATION AND QUANTIFICATION OF PROTEINS IN WHEY OBTAINED AS A BY-PRODUCT FROM WHITE CHEESE AND YELLOW CHEESE PRODUCTION

After the cheese production process, the whey, obtained as a by-product, is not valorised and remains in the waste water which is usually disposed of in natural watercourses. The aim of the study was to analyse the profile of whey proteins, as well as, to quantify the amount of those fractions. 12.5 % SDS-PAGE was used. The total amount of proteins in whey from cow white cheese was 0.73 % ± 0.15, while in cow kashkaval whey was 0.91 % ± 0.08. In whey from white cheese, the relative protein percentages were: lactoglobulin 67.29 % ± 4.99, lactalbumin 20.64 % ± 2.02 and other fractions related to bovine serum albumin with 12.07 % ± 3.05. In whey from yellow cheese, the proteins percent-ages were: lactoglobulin 52.62 % ± 1.21, lactalbumin 17.62 % ± 1.26 and other fractions related to bovine serum albu-min with 29.74 %, respectively. Predominantly, -lactoglobulin was present in the analysed samples. The valorisation of the waste whey obtained in the white cheese production, and development of new product also contributes in the en-vironment protection.

The use of microbiological methods to reduce aflatoxin M1 in cheese

Studies have shown evidence of human exposure to aflatoxin M1 due to the consumption of contaminated milk and dairy products (mainly cheeses). This poses a great risk to public health, since milk and milk products are frequently consumed by a portion of the population considered immunosuppressed, children and the elderly. Knowledge of the negative impacts of aflatoxins on health and economics has led to investigations of strategies to prevent their formation in food, as well as to eliminate, inactivate or reduce the bioavailability of these toxins in contaminated products This study evaluated the effect of microbiological methods using lactic acid bacteria on aflatoxin M1 (AFM1) reduction in Minas Frescal cheese (typical Brazilian product, being among the most consumed cheeses in Brazil) spiked with 1 µg l−1 AFM1. Inactivated lactic acid bacteria (0, 5%, v/v de L. rhamnosus e L. lactis) were added during the cheese production process. Nine cheeses were produced, divided into three treatments: negative controls (without AFM1 or lactic acid bacteria), positive controls (AFM1 only), and lactic acid bacteria+AFM1. Samples of cheese were collected on days 2, 10, 20 and 30 after the date of production and submitted to composition analyses and determination of AFM1 by high performance liquid chromatography. The reductions of AFM1 in cheese by lactic acid bacteria at the end of the trial indicate a potential application of inactivated lactic acid bacteria in reducing the bioavailability of AFM1 in Minas frescal cheese without physical-chemical and microbiological modifications during the 30 day experimental period.

Energy demand and carbon footprint of cheddar cheese with energy recovery from cheese whey

This study evaluates the life cycle environmental sustainability of cheddar cheese with energy recovery from cheese whey via anaerobic digestion. Environmental hotspots and improvement opportunities along the supply chain are also identified. The cheddar cheese production process has been simulated by using Aspen Plus. The environmental impacts have been estimated through life cycle assessment (LCA) using the outputs from process simulation. The LCA data for the rest of the life cycle have been sourced from databases and literature. The results reveal that the total primary energy consumed in the whole life cycle of cheddar cheese is 347 MJ, with the carbon footprint equal to 14 kg CO2 eq. per kg of cheddar. Energy recovered from anaerobic digestion of whey reduces the total life cycle primary energy demand and the carbon footprint by only 2%. Much greater reductions could be achieved by targeting milk production and storage of cheese. However, anaerobic digestion of whey makes the cheese production process energy self-sufficient and reduces the production costs. It also makes the production process carbon negative, reducing its carbon footprint from 0.12 to -0.12 kg CO2 eq./kg due to the credits for electricity and heat produced from biogas.

Production of whey protein as nutritional valuable foods

Whey is a low calorie milk serum remaining after casein removal in cheese manufacturing. Composition and properties of whey depend on the type of cheese production process, type and the quality of the used milk. Whey mostly consists of lactose, proteins, vitamins, minerals, enzymes, hormones and growth factors. Functional and nutritional roles of whey components meet the requirements for dietary food. Whey proteins are liquid fractions of 20% milk proteins, which remain in whey after casein removal. The increase in the temperature of milk processing leads to denaturation of proteins and a decrease in their content. The most common whey proteins are albumin and globulin. Separation and fractionation of whey proteins may be carried out as precipitation, combined with acid treatment, high temperature treatment or centrifugation (centry-whey process), and as a membrane process (usually ultra- or microfiltration followed by a diafiltration and spray drying). Whey proteins can also be separated based on their molecular mass, charge and hydrophobicity. It is a well-known fact that whey proteins possess admirable nutritional and functional components, such as essential amino acids, bioactive peptides, antioxidants and immunopotentiators. Research of bioactive compounds and nutrients pushed whey protein to the forefront of the functional food sector, therefore, the implementation of these proteins in the diet and supplements has the potential to address many metabolic imbalance-caused diseases, and it seems imperative to harness their potential.

Effect of the addition of liquid whey from cheese making factory on the physicochemical properties of whey protein isolate gels made by high hydrostatic pressure.

The objective of the present work was to study the effect of liquid whey from the cheese production process on the gels developed by high hydrostatic pressure from whey protein isolate powder (WPI). Changes in pH, color, textural parameters, and water retention capacity of the gels obtained were analyzed during storage for 28days at refrigeration temperature (4°C). Mixtures of liquid whey from cheese making processes and different WPI percentages gave gels with different characteristics after being processed by high hydrostatic pressures. The pH values and color parameters (L*, a*, b*) varied slightly, depending directly on WPI concentration and storage time. The values of hardness, elasticity, and cohesiveness were dependent on the liquid medium used to dissolve the WPI (liquid cheese whey or distilled water), WPI concentration, and storage time. The use of liquid cheese whey for gel formation favored water retention, reducing the appearance of syneresis (exudation). The results obtained in the present study indicated a possible use and revalorization of cheese whey obtained in cheese production to obtain WPI gels with improved physicochemical properties, using high hydrostatic pressure as technology for their production.

Effective dose analysis of extremely low frequency (ELF) magnetic field exposure to growth of S. termophilus, L. lactis, L. acidophilus bacteria

The Extremely Low Frequency (ELF) magnetic field, which is a component of a non-ionizing radiation, at low intensity has been shown to increase cell proliferation. This fact is expected to lead to a technological breakthrough in S. thermophilus, L. lactis, and L. acidhopilus bacteria activation which is needed in the production process of cream cheese. The main issue considered here in the production process of cream cheese is the growth of bacteria which often cannot be optimal, causing it to taste bad. This study is an initial step to determine the effective dose of exposure to ELF magnetic fields on the S. thermophilus, L. lactis, and L. acidhopilus bacteria growth. This research used the exposure of ELF magnetic field with intensity of 100 µT and 300 µT to those three types of bacteria with exposure durations of 5, 15, 25, 35, and 45 minutes. Measurements of the amount of bacteria were performed 1 hour, 2 hours, and 16 hours after exposure to ELF magnetic field. The results of this study indicated that the growth of three types of bacteria exposed to ELF magnetic field with an intensity of 100 µT was significantly faster than the control one, but the other one which were exposed to 300 µT ELF magnetic field was not different from the control one. The analysis results provided evidence that the rate of optimal growth occurred in three types of bacteria after being exposed to 100 µT ELF magnetic fields for 5 minutes. Therefore, it could be concluded that exposure to ELF magnetic field with an intensity of 100 µT for 5 minutes is an effective dose for the activation of S. thermophilus, L. lactis, and L. acidhopilus bacteria growth.

Traditional Cottage Cheese production in Kosovo

The study was conducted to identify the technological process of cottage cheese production as well as its diversity produced in traditional way in Kosovo. The data were collected by survey realized during the period October 2015 – April 2016. The sample size was calculated as 450 small-scale households and was randomly selected, representing all regions of Kosovo. The data were collected by face to face survey in rural settlements. The study was focused on the mode of cottage cheese production, as a way of coagulation, pasteurization, storage and use of cottage cheese produced. According to study result, it was found that Kosovo is characterized by a very small diversity of cottage cheese produced in the traditional form and the technological process of curd production differ slightly between the regions of Kosovo (mainly in the way of coagulation of curd).

Amplicon and shotgun metagenomic sequencing indicates that microbial ecosystems present in cheese brines reflect environmental inoculation during the cheese production process

The taxonomic diversity of the microbial communities associated with stable 30-y old cheese brines from an artisan and large-scale cheese producer located in Flanders, Belgium, was investigated culture-independently. High-throughput amplicon and shotgun metagenomic sequencing revealed species of Tetragenococcus, Chromohalobacter, and Halanaerobium as the most abundant ones in both brines. Debaryomyces was the only yeast genus detected. All these halophiles might originate from the salt used and might survive and even grow in the brines. The occurrence of different and/or additional species in the two brines could be due to differences in salt concentrations. A second group of microorganisms, possibly incapable of growth in the brines, could be mainly associated with the cheese production ingredients, such as the rennet (Lactobacillus rennini), starter culture (Lactococcus lactis) or raw milk used (Lc. lactis and Staphylococcus equorum). This specific brine microbiota might have an impact on the ultimate quality of the cheeses produced.

Carrageenan as a functional additive in the production of cheese and cheese-like products.

Carrageenan is a well-known gelling agent used in the food industry. The present review of patent and scien- tific literature shows that carrageenan is a useful additive in the cheese production process. The gel-strength- ening properties of carrageenan are as a result of the fairly strong bonds it forms with casein macromolecules. However, carrageenan-casein interaction is dependent on pH. Different carrageenan types have different charge levels (the most charged is the helix form of lambda-carrageenan), which affects the carrageenan- casein aggregates. The correct concentration of carrageenan and temperature treatment can improve cheese yield and whey protein recovery, which is desirable for cheese producers. Even small amounts of this hydro- colloid can increase cheese firmness and maintain cheese structure after cheese curd heating. Carrageenan improves cheese structure and other properties, such as ease of grating or slicing, which are very important for customers. Some modifications to cheese composition can destroy the natural cheese structure, but the addition of carrageenan can be useful for creating modified cheese-like products with desirable attributes. Carrageenan can be a good replacement for emulsifying salts, to stabilize cheese fat without disturbing the Ca:P ratio. The replacement of emulsifying salts with carrageenan (as little as 1%) results in a homogenous cheese product. For that reason, carrageenan is a useful additive for maintaining the organoleptic and struc- tural values of fat-free cheese. Carrageenan can also stabilize the structure in cheese-like products and replace casein in cheese imitations.

Potential use of ricotta cheese whey for the production of lactobionic acid by Pseudomonas taetrolens strains

Lactobionic acid (LBA) is a fine chemical largely applied in the food, chemical, cosmetics and pharmaceutical industries. Here, its production from ricotta cheese whey (RCW), or scotta, the main by-product obtained from ricotta cheese production process and currently employed mainly for cattle feed, was evaluated. Among seven bacterial species tested, only two Pseudomonas taetrolens strains were selected after preliminary screening in shake-flasks. When autoclaved RCW was used, a lactobionic acid titer of 34.25 ± 2.86 g/l, with a conversion yield (defined as mol LBA/mol of consumed lactose%) of up to 85 ± 7.0%, was obtained after 48 h of batch fermentation in 3 L stirred tank bioreactor. This study is a preliminary investigation on the potential industrial use of scotta as a substrate for bacterial growth and lactobionic acid production that details the possible biotechnological valorization pathways and feasibility of the process.