Mozzarella Cheese Stretching: A Minireview

Characterization of Volatile Compounds in Mozzarella Cheeses Made from Bovine and Buffalo Milk by SPME-GC×GC-O-TOFMS, SPME-Arrow-GC-MS and GC-IMS

High moisture Mozzarella cheese is particularly popular because of its freshness and milky flavor, however the difference in aroma compound composition between high moisture Mozzarella cheese made from bovine (BOC) and buffalo milk (BUC) remains unclear. Herein, the volatile compounds of 2 kinds of Mozzarella cheese were qualitatively and quantitatively analyzed by SPME-GC × GC-O-TOFMS, SPME-Arrow-GC-MS and GC-IMS for the first time. A total of 139 volatile compounds were identified (69 aroma active compounds were sniffed), of which 106 were identified in BOC and 96 in BUC. About 70.5% of these compounds can be identified by GC × GC-O-TOFMS, exceeding 2.6 times that of GC-IMS. Particularly, 2-methyltetrahydrofuran-3-one (nutty flavor, odor intensity in 3) and methoxy-phenyl-oxime (burnt flavor, 689.47 ± 48.32 μg/kg, odor intensity in 5) were identified as aroma active compounds in BOC for the first time. The sensory evaluation confirmed that 2-methyltetrahydrofuran-3-one is one of the factors responsible for the differences in nutty flavor observed between BOC and BUC. Compared with the 3 aroma extract techniques (SPME, SPME-Arrow and headspace), SPME-Arrow can increase the adsorption capacity of volatile compounds in samples, but required the high separation and high sensitivity detection equipment for more efficient identification of volatile compounds. The combination of the GC × GC-O-TOFMS, GC-MS, and GC-IMS had obtained a comprehensive aroma profile of Mozzarella cheese, which laid a theoretical foundation for the construction of aroma fingerprints of Mozzarella cheeses from different milk sources, and provided a basis for the development and application of new dairy products.

Effect of saturated and unsaturated fat on the physical properties of plant-based cheese

In many plant-based meat and dairy alternatives, coconut oil is frequently used to replicate the textural and structural properties of animal fats due to its high saturated fat content. Concerns about the health implications of saturated fat and the sustainability of coconut oil call for an exploration into alternative fat combinations in plant-based foods. The effects of saturated fatty acid (SFA) content on plant-based cheese physical characteristics were evaluated through five different ratios of coconut oil (CO) to sunflower oil (SO): 100%, 90%, 75%, 60%, 50%, 40%, 25%, 10%, and 0%. As determined through texture profile analysis, the hardness of the cheeses after setting at 5°C for 24h increased with increasing amounts of coconut oil due to the increasing solid fat content providing additional firmness. The samples with 100% coconut oil displayed satisfactory melt and stretch; however, the melt and stretch values were matched by adding as little as 25% sunflower oil. The melt and stretch values did not continue to increase with increasing saturated fat content but instead remained constant with increasing coconut oil addition. Rheological analysis of the cheeses during a temperature ramp from 20 to 95°C was assessed where the tanδ value at 95°C was used as a measure of cheese melt, where values ≥ 1 indicated a better melt. The 0% coconut oil cheese had the lowest tanδ (G″/G') value of 0.3, whereas the addition of 25% coconut oil into the cheese resulted in the tanδ increasing to values greater than 0.5. The 25% CO cheese sample also achieved a more similar complex viscosity (η*) to that of dairy cheese than all samples but the 75% CO cheese. Therefore, there is an opportunity to decrease the amount of coconut oil in plant-based cheese systems while maintaining good functional properties and improving the sustainability and health benefits of the final product.

Methodology and development of a high-protein plant-based cheese alternative

Animal-based food products, such as meat and dairy, contribute the most to greenhouse gas emissions in the food sector. This, coupled with the demonstrably worsening climate crisis, means that there needs to be a shift to more sustainable alternatives in the form of plant-based foods. In particular, the plant-based cheese alternative industry is relevant, as the products lack critical functionalities and nutrition compared to their dairy-based counterparts. Waxy starch, plant-protein isolate, and coconut oil were combined to create a novel high-protein (18% w/w) plant-based cheese alternative. We determined that when using native waxy starch, we can enhance its existing viscoelastic properties by modulating gelatinization through adding plant protein and fat. Texture profile analysis indicated that the cheese analogues could reach hardness levels of 15-90N, which allowed samples to be tailored to a broader range of dairy products. We determined that plant proteins and fat can behave as particulate fillers, enhance network strength, and create strategic junction points during starch retrogradation. The degree of melt and stretch of the high-protein plant-based analogues were 2-3 times greater than those observed for commercial plant-based cheese alternatives and significantly more similar to dairy cheese. The rheological melting kinetics saw that the high-protein plant-based cheese alternative displayed more viscous properties with increasing temperature. Tan δ (G"/G') at 80 °C was used as an indicator for sample meltability where, values ≥ 1 indicate better melt and more viscous systems. The high-protein plant-based cheese alternative reached Tan δ values upwards to 0.7, whereas commercial plant-based cheese alternatives only reached tan δ values around 0.1. Ultimately, the novel high-protein plant-based cheese alternative demonstrates the use of simple ingredients to form complex food systems.

Possibility of Using Different Calcium Compounds for the Manufacture of Fresh Acid Rennet Cheese from Goat's Milk

Calcium can be added to cheese milk to influence the coagulation process and to increase cheese yield. Calcium compounds used in the dairy industry show substantial differences in their practical application. Therefore, this study aimed to evaluate the potential use of 0, 5, 10, 15, and 20 mg Ca 100 g-1 of milk in the form of calcium gluconate, lactate, and carbonate as alternatives to calcium chloride in manufacturing fresh acid rennet cheese from high-pasteurized (90 °C, 15 s) goat's milk. The pH value of the cheese was reduced most strongly by the addition of increasing doses of calcium lactate (r = -0.9521). Each cheese sample showed increased fat content with the addition of calcium. Only calcium chloride did not reduce protein retention from goat's milk to cheese. The addition of 20 mg Ca 100 g-1 of milk in the form of gluconate increased cheese yield by 4.04%, and lactate reduced cheese yield by 2.3%. Adding each calcium compound to goat's milk significantly increased Ca and P levels in the cheese (p ≤ 0.05). The highest Ca levels were found in cheese with the addition of 20 mg Ca 100 g-1 of milk in the form of lactate. In all groups, similar contents of Mn, Mo, and Se were found. Calcium addition significantly affected cheese hardness, while higher calcium concentrations increased hardness. Carbonate caused the greatest increase in the cohesiveness of cheese. The addition of calcium compounds increased the adhesiveness and springiness of cheese compared to controls. The cheese with calcium chloride had the highest overall acceptability compared to the other cheese samples. The addition of calcium carbonate resulted in a lower score for appearance and consistency, and influenced a slightly perceptible graininess, sandiness, and stickiness in its consistency, as well as provided a slightly perceptible chalky taste.

Investigation of the influence of xanthan on mozzarella cheese characteristics focusing on its antimicrobial effect

Objective

This study was designed to show the effect of adding different levels of microbial (lab-produced) and commercial xanthan (CX) for 30 days on the sensory, chemical, and microbiological parameters of mozzarella cheese (MC).

Materials and Methods

The production of xanthan was done in Garcia-Ochoa's medium. The sensory evaluation of the examined MC was achieved through a tabulated scorecard. The Gerber method was used for the determination of MC fat%. The mean counts of staphylococci [colony forming unit (CFU)/gm], coliforms (most probable number/gm), fungi (CFU/gm), and mesophilic bacteria (CFU/gm) were estimated in different fortified cheeses. Also, mean counts of Escherichia coli O157 and Staphylococcus aureus in artificially contaminated MC were determined.

Results

The microbial xanthan (MX) had a significant (p < 0.05) effect on the sensory parameters of the examined samples with its concentration (0.0007%) after 20 days of storage. The MX (0.0005%) and CX (0.0002%) had a significant effect on moisture, fat in dry matter, and protein percentage of MC throughout the storage period. The high meltability degree of MC was observed in samples with both types of xanthan (0.0002%) at the end of storage.

Conclusion

Both types of xanthan at all concentrations had a significant reducing effect on E. coli O157 and S. aureus in all samples from 10 to 30 days of storage. Xanthan has accepted attentiveness and offers beneficial and safe characteristics that improve its adaptability in MC. In the Middle East, this survival trial of E. coli O157 and S. aureus in the MC supplemented by xanthan is considered a scarce exploratory investigation.

Effect of a new sustainable cooling system used during firming and brining on the microbiological, chemical, and sensory characteristics of buffalo mozzarella cheese

The cooling applied during the firming and brining processes represents an important production step in mozzarella cheese-making. The temperature fluctuations of the cooling water can negatively affect the hygiene, composition, and quality of mozzarella. Some sustainable cooling systems can minimize this problem by using hot process fluids as heat sources to generate refrigerated energy. This study aimed to evaluate the effects of a new cooling system equipped with a water-ammonia absorption chiller (MA) on the characteristics of buffalo mozzarella through a comparative study with products cooled with a traditional ice water chiller (MT). The buffalo mozzarella cheese manufacture was monitored, and the samples were analyzed for chemical, nutritional, microbiological, and sensory characteristics. The MT samples showed an overall weight loss of 7.4% compared to an average of 2.8% for the MA samples. The MT samples were characterized by greater sapidity than the MA ones, which instead showed a higher moisture content that increased juiciness. The microbiological analysis showed a lower concentration of mesophilic bacterial load in the MA samples than in the MT ones [difference of 1 Log (CFU/g)], which is probably due to the low and constant temperatures that reduced the permanence time of the mozzarella in the vats (firming and brining). This study represents a preliminary positive evaluation of the use of this sustainable cooling system for mozzarella cheese, which is useful for dairy plants with an annual cheese production volume sufficient to justify the operating cost of the plant and the annual energy cost.

Thermal Inactivation of Salmonella enterica and Listeria monocytogenes in Quesillo Manufactured from Raw Milk

Quesillo is an artisanal Honduran cheese made from raw milk. During fabrication, curd melting is considered a killing step for pathogenic bacteria. This work was aimed at determining the survival of Salmonella enterica and Listeria monocytogenes on inoculated curd packaged in plastic bags and immersed in a water bath at 48, 54, 60, 65, and 70°C for predetermined times. Survival counts of each pathogen were used to estimate D values by linear regression, and z values were estimated by the linear regression of the D values. S. entericaD values ranged from 4.5 min at 60°C to 0.80 min at 70°C (z = 10.7°C). For L. monocytogenes, D values ranged from 6.08 min at 60°C to 0.90 min at 70°C (z = 11.3°C). Validation of 7-log reduction was performed on inoculated curd heated at 65°C for 34.7 min, and recovering enrichment procedures were used for each pathogen. Neither S. enterica nor L. monocytogenes cells were recovered after the enrichment of samples. The results obtained in this study could be applied by Honduran quesillo processors to improve the safety of their products.