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1.
Cheddar-type cheeses were manufactured using fermentation-produced camel or calf chymosin. There were no significant differences in the composition and pH between the cheeses made with either coagulant. The extent of primary proteolysis was significantly lower in cheeses made with camel chymosin than in cheeses made with calf chymosin. There were large quantitative differences between the peptide profiles of cheeses; however, the levels of amino acids were similar except for isoleucine, histidine and lysine. The cheeses made with camel chymosin were characterized by lower intensities of sulphur and brothy flavours and showed less bitter taste; however, the cheeses made with calf chymosin had greater breakdown of texture, higher smoothness and mouthcoating and were more cohesive and adhesive. The results of this study suggest that camel chymosin appears to be suitable for making Cheddar cheese with lower levels of proteolysis but with good flavour.  相似文献   

2.
Beyaz peynir, a white brined cheese, was manufactured using different blends of camel chymosin (100, 75, 50, 25, and 0%) with calf chymosin and ripened for 90 d. The purpose of this study was to determine the best mixture of coagulant for Beyaz peynir, in terms of proteolysis, texture, and melting characteristics. The cheeses were evaluated in terms of chemical composition, levels of proteolysis, total free amino acids, texture, meltability, residual coagulant activity, microstructure, and sensory properties during 90 d of ripening. Differences in the gross chemical composition were statistically significant for all types of cheeses. Levels of proteolysis were highly dependent on the blends of the coagulants. Higher proteolysis was observed in cheeses that used a higher ratio of calf chymosin. Differences in urea-PAGE and peptide profiles of each cheese were observed as well. Meltability values proportionally increased with the higher increasing levels of calf chymosin in the blend formula. These coagulants had a slight effect on the microstructure of cheeses. The cheese made with camel chymosin had a harder texture than calf chymosin cheese, and hardness values of all cheese samples decreased during ripening. The cheeses with a high ratio of calf chymosin had higher residual enzyme activity than those made with camel chymosin. No significant difference in sensory properties was observed among the cheeses. In conclusion, cheeses made with a high level of calf chymosin had a higher level of proteolysis, residual coagulant activity, and meltability. The cheeses also had a softer texture than cheeses made with a high content of camel chymosin. Camel chymosin may be used as a coagulant alone if low or limited levels of proteolysis are desired in cheese.  相似文献   

3.
Solanum elaeagnifolium (trompillo or silverleaf nightshade) is an endemic plant from the northeast of Mexico and southwest of United States. This plant is considered as a weed with negative impact on agriculture and livestock production. Nevertheless, in some places of Chihuahua, Mexico, the berries of this plant have been used for decades in the manufacture of artisanal filata-type asadero cheese. The milk-clotting enzyme of S. elaeagnifolium has been scarcely studied; for this reason, the aim of this work was to explore some properties of this plant coagulant. Protein extracts (PEs) from ripe berries of S. elaeagnifolium were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and assessed for milk-clotting activity. In addition, milk gels and miniature fresh-type cheeses manufactured with the plant coagulant were analyzed for their texture properties. The PE from the berries of S. elaeagnifolium contained 8 proteins with molecular weights from 22 to 62 kDa. Some bands observed in the PE had similar molecular weights as reported for aspartic proteinases such as chymosin. The extracts from the berries of S. elaeagnifolium had lower milk-cloting activities than observed with rennin or chymosin, but this plant coagulant produced firm gels under acidic conditions. The mini-cheeses manufactured with this coagulant were softer than cheeses manufactured with rennin or chymosin. For this reason, the coagulant from the ripe berries of S. elaeagnifolium could be suitable not only for the manufacture of filata-type cheeses but also for the manufacture of soft cheeses such as cream cheese. PRACTICAL APPLICATION: Silverleaf nightshade (trompillo) is a plant that grows in northern Mexico and the southwestern United States. This plant is considered a weed with negative impact on agriculture and livestock production. However, the ripe berries of this plant have been used by ancient Pima Indians as a substitute of rennin in making cheese. In this work, it was observed that this plant coagulant had lower activity and produced softer cheeses than did rennin or chymosin. For this reason, the coagulant from berries of S. elaeagnifolium could be used for the manufacture of soft cheeses such as cream cheese.  相似文献   

4.
Powdered plant coagulant (PPC) obtained from the cardoon (Cynara cardunculus) was compared with calf rennet (CR) for the manufacture of goats’ milk cheese, by determining difference in the proteolysis throughout ripening. There were no substantial differences between the compositions of cheeses made using the two types of coagulants. However, cheeses manufactured with PPC exhibited higher levels of pH 4.6-SN than cheese made using CR. The extent of breakdown of αs-casein, as measured by urea-PAGE, was greater in cheese made using PPC than cheese made using CR. The formation of hydrophobic peptides and the ratio of hydrophobic/hydrophilic peptides throughout the ripening were higher in cheeses made with PPC than in cheeses made with CR. Principal component analysis (PCA) of peak heights of RP-HPLC peptide profiles of the ethanol-soluble and ethanol-insoluble fractions distributed the samples according to the coagulant used in their manufacture. Quantitative differences in several peptides were evident between the two types of cheese.  相似文献   

5.
This article reports on a study of the sensorial characteristics of ewe milk cheese (Los Pedroches) made with animal rennet and two types of coagulant obtained from the cardoon Cynara cardunculus. The cheeses made with rennet displayed a less odor intensity: pungent odor and acid odor; a less acid taste; and a slightly lighter color. They were harder and firmer, but less creamy than those made with the vegetable coagulant (powdered vegetable coagulant [PVC] and crude aqueous extract [CAE] from C. cardunculus). However, the cheeses made with PVC showed organoleptic characteristics very similar to the cheeses made with CAE from C. cardunculus. After 90 days' ripening, the cheeses made with vegetable coagulant displayed a slightly more bitter taste than those made with rennet. In general terms, increased ripening time prompted the increased scores for most of the sensory attributes studied.  相似文献   

6.
Prato cheeses were manufactured using coagulant from Thermomucor indicae-seudaticae N31 or a commercial coagulant. Cheeses were characterised using the following analysis: yield; fat; acidity; moisture; ash; salt; pH; total nitrogen; total protein; NS-pH 4.6/NT*100; NS-TCA 12%/NT*100; casein electrophoresis; and RP-HPLC. The results were statistically analysed and revealed that the proteolytic indices were not significantly different throughout the 60 days of ripening of cheeses made with either coagulant. Even though there were some quantitative differences in the peptide profile of cheeses, the enzyme from T. indicae-seudaticae N31 was used in the production of good quality Prato cheese without having to change the established technological parameters of the process.  相似文献   

7.
Milkfat sucrose polyesters (SPE) were substituted for 10, 25, 50, or 75% (w/w) of mllkfat in reconstituted milk and made into Cheddar-type cheeses. Total fat, moisture, and salt contents of the cheeses averaged 27, 49, and 1.2% (w/w). respectively. A screened sensory panel (n=22) determined that cheeses containing SPE were significantly different from the control cheese. Colorlmetrlc measurements of the total difference (ΔE) of the cheeses containing SPE from the control cheese increased as % SPE in the cheese increased (r=0.90). Firmness of the cheeses did not differ (p<0.05). Cheddar-type cheeses made with mllkfat SPE substituted for milkfat may have potential marketability.  相似文献   

8.
The objectives were to reduce bitterness in reduced-fat Cheddar cheese made with an exopolysaccharide (EPS)-producing culture and study relationships among ultra-filtration (UF), residual chymosin activity (RCA), and cheese bitterness. In previous studies, EPS-producing cultures improved the textural, melting, and viscoelastic properties of reduced-fat Cheddar cheese. However, the EPS-positive cheese developed bitterness after 2 to 3 mo of ripening due to increased RCA. We hypothesized that the reduced amount of chymosin needed to coagulate UF milk might result in reduced RCA and bitterness in cheese. Reduced-fat Cheddar cheeses were manufactured with EPS-producing and nonproducing cultures using skim milk or UF milk (1.2×) adjusted to a casein:fat ratio of 1.35. The EPS-producing culture increased moisture and RCA in reduced-fat Cheddar cheese. Lower RCA was found in cheese made from UF milk compared with that in cheese made from control milk. Ultrafiltration at a low concentration rate (1.2×) produced EPS-positive, reduced-fat cheese with similar RCA to that in the EPS-negative cheese. Slower proteolysis was observed in UF cheeses compared with non-UF cheeses. Panelists reported that UF EPS-positive cheese was less bitter than EPS-positive cheese made from control milk. This study showed that UF at a low concentration factor (1.2×) could successfully reduce bitterness in cheese containing a high moisture level. Because this technology reduced the RCA level (per g of protein) to a level similar to that in the control cheeses, the contribution of chymosin to cheese proteolysis would be similar in both cheeses.  相似文献   

9.
Reduced NaCl in semi-hard cheeses greatly affects textural and sensory properties. The interaction between cheese NaCl concentration and texture was affected by brining time (0–28 h), dl-starter cultures (C1, C2, and C3), chymosin type (bovine or camel), and ripening time (1–12 weeks). Cheese NaCl levels ranged from <0.15 to 1.90% (w/w). NaCl distribution changed during ripening; migration from cheese edge to core led to a more homogeneous NaCl distribution after 12 weeks. As ripening time increased, cheese firmness decreased. Cheeses with reduced NaCl were less firm and more compressible. Cheeses produced with C2 were significantly firmer than those produced with C1; cheeses produced with C3 had higher firmness and compressibility. In NaCl reduced cheese, use of camel chymosin as coagulant resulted in significantly higher firmness than that given using bovine chymosin. Overall, cheese NaCl content is reducible without significant textural impact using well-defined starter cultures and camel chymosin.  相似文献   

10.
The combined use of chymosin and Cryphonectria parasitica protease was evaluated for manufacturing Cheddar cheese at different chymosin-to-C. parasitica protease ratios of 1:0, 0:1, 67:33, and 33:67. The degree of proteolysis over time was affected by the coagulant type. Proteolysis was thought to be the main cause of changes in functional properties of Cheddar cheeses. The meltability and hardness of cheese made with 100% C. parasitica enzyme was the highest, but it was high in bitterness. The chymosin-to-C. parasitica ratio between 0:1 to 67:33 was found suitable to independently control Cheddar cheese meltability and hardness without a significant level of bitterness.  相似文献   

11.
The impact of soy protein isolate on the proteolysis and organoleptic properties of Cheddar-type cheese during ripening was studied. Cheese was prepared from cow's milk (control) and cow's milk plus soy protein isolate by using a starter culture of Streptococcus thermophilus and Lactobacillus delbrueckii subsp . bulgaricus, and then ripened at 12  ±  1°C for 3 and 5 months. The molecular weight range and peptide fraction in the cheeses were determined by high-performance liquid chromatography (HPLC), and the microstructure was observed by scanning electron microscopy (SEM). Sensory evaluation was used to compare the flavour, body, texture and appearance of the cheeses. The results show that the molecular weight range (9924–9966  Da) in the control cheese was larger than that (6954–6957   Da) in the soy protein-treated cheese and the microstructure in the latter was less compact than in the control cheese. In the sensory evaluation, higher scores were given for some experimental cheese than the control cheese. After 5 months of ripening, the organoleptic properties of the cheese had markedly improved and no bitter off-flavour was detected in the treated cheeses. It was concluded that soy protein could be used to improve the quality of cheese and the addition of 5% soy protein isolate could be recommended for improving the flavour and texture of Cheddar-type soy supplemented cheese.  相似文献   

12.
This study compared the chemical composition and fatty acid (FA) profile of Manchego type cheese and Panela cheese made from hair sheep milk and compared these with both types of cheese manufactured with cow milk as a reference. In addition, this study aimed to determine differences in sensory characteristics between Manchego type cheeses manufactured with either hair sheep milk or cow milk. A total of 25 and 14 Manchego type cheeses from hair sheep milk and cow milk were manufactured, respectively. In addition, 30 and 15 Panela cheeses from hair sheep milk and cow milk were manufactured, respectively. The chemical composition and FA profile were determined in all cheeses. In addition, a sensory analysis was performed in Manchego type cheeses manufactured from either hair sheep milk or cow milk. Moisture content was lower in Manchego type cheeses (37.5 ± 1.26 and 37.5 ± 1.26 g/100 g in cheeses manufactured from hair sheep milk and cow milk, respectively) than in Panela cheeses (54.0 ± 1.26 and 56.1 ± 1.26 g/100 g in cheeses manufactured from hair sheep milk and cow milk, respectively). Ash, protein, and sodium contents were higher in Manchego type cheeses than in Panela cheeses. Manchego type cheese manufactured from hair sheep milk contained more C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C18:2 cis-9,cis-12, total saturated FA, total short-chain FA, total medium-chain FA, total polyunsaturated FA, and de novo FA than Manchego type cheeses from cow milk. Total content of short-chain FA was higher in hair sheep cheeses (24.4 ± 1.30 and 19.6 ± 1.30 g/100 g in Manchego type and Panela cheeses, respectively) than in cow cheeses (8.89 ± 1.30 and 8.26 ± 1.30 g/100 g in Manchego type and Panela cheeses, respectively). Manchego type cheeses from hair sheep milk obtained higher scores for odor (7.05), texture (6.82), flavor (7.16), and overall acceptance (7.16) compared with those made from cow milk (6.37, 6.12, 6.17, and 6.83, respectively). In conclusion, both Manchego type cheese and Panela cheese manufactured with hair sheep milk had a similar chemical composition and contained higher levels of short-chain FA, total polyunsaturated FA, and de novo FA than those manufactured with cow milk.  相似文献   

13.
The objective of this study was to compare the effect of coagulant (bovine calf chymosin, BCC, or camel chymosin, CC), on the functional and sensory properties and performance shelf-life of low-moisture, part-skim (LMPS) Mozzarella. Both chymosins were used at 2 levels [0.05 and 0.037 international milk clotting units (IMCU)/mL], and clotting temperature was varied to achieve similar gelation times for each treatment (as this also affects cheese properties). Functionality was assessed at various cheese ages using dynamic low-amplitude oscillatory rheology and performance of baked cheese on pizza. Cheese composition was not significantly different between treatments. The level of total calcium or insoluble (INSOL) calcium did not differ significantly among the cheeses initially or during ripening. Proteolysis in cheese made with BCC was higher than in cheeses made with CC. At 84 d of ripening, maximum loss tangent values were not significantly different in the cheeses, suggesting that these cheeses had similar melt characteristics. After 14 d of cheese ripening, the crossover temperature (loss tangent = 1 or melting temperature) was higher when CC was used as coagulant. This was due to lower proteolysis in the CC cheeses compared with those made with BCC because the pH and INSOL calcium levels were similar in all cheeses. Cheeses made with CC maintained higher hardness values over 84 d of ripening compared with BCC and maintained higher sensory firmness values and adhesiveness of mass scores during ripening. When melted on pizzas, cheese made with CC had lower blister quantity and the cheeses were firmer and chewier. Because the 2 types of cheeses had similar moisture contents, pH values, and INSOL Ca levels, differences in proteolysis were responsible for the firmer and chewier texture of CC cheeses. When cheese performance on baked pizza was analyzed, properties such as blister quantity, strand thickness, hardness, and chewiness were maintained for a longer ripening time than cheeses made with BCC, indicating that use of CC could help to extend the performance shelf-life of LMPS Mozzarella.  相似文献   

14.
Pepstatin A, an inhibitor of acid proteases, was added (7.5, 15 or 30 μmol L-1) to the curds/whey mixture at the start of cooking to inhibit residual coagulant in miniature (20 g) Cheddar-type cheeses. No degradation of s1-casein was observed by urea–polyacryl amide gel electrophoresis (PAGE) in the pepstatin-treated cheeses, indicating that all the concentrations of pepstatin used in this study effectively inhibited residual coagulant throughout ripening. The level of water-soluble N (WSN) as % of total N increased very slowly in the pepstatin-treated cheeses, while there was a steady increase in WSN in the control cheeses; after 4 months of ripening, the level of WSN in the control cheese was nearly three times as high as in the cheese treated with 30 μmol L-1 pepstatin. Urea–PAGE of water-soluble fractions (WSF) showed marked differences between pepstatin-treated cheeses and their respective controls throughout ripening. Reverse-phase HPLC of the WSF of the cheeses showed that the peptides s1-CN f1-9/13, which are formed from the chymosin-produced peptide, s1-CN f1-23, by the action of the cell envelope-associated proteinase of Lactococcus, were not present in pepstatin-treated cheeses. Levels of total free amino acids (as determined by the Cd–ninhydrin method) were higher in controls than in pepstatin-treated cheeses throughout ripening. The results of this study demonstrated that pepstatin is a very effective inhibitor of residual coagulant in cheese.  相似文献   

15.
The aims of the present study were to determine compositional characteristics of Murcia al Vino goat's cheese and to evaluate the effect of different types of coagulants (animal rennet and powdered vegetable coagulant obtained from the cardoon Cynara cardunculus ) on the improvement of the technological quality of Murcia al Vino goat's cheese. Only the pH, TA and ash and Ca contents were affected in a significant way by the type of coagulant used. There was a decrease in the moisture and an increase in the sodium chloride during ripening, while other parameters were unchanged. The pH and titratable acidity (TA) values of the cheeses were affected significantly by the time of ripening. There was an increase of the Na as well as a significant decrease of the Ca, P, Zn, Cu and Fe components, as a consequence of the increase of the acidity of the cheese during ripening. The esterified fatty acids were not modified significantly by the type of coagulant or by the time of ripening. Those most abundant in this type of cheese were C16 and the C18 : 1.  相似文献   

16.
BACKGROUND: Enzymes present in the flowers of Cynara cardunculus (cyprosins) are used in the production of some traditional Spanish and Portuguese cheeses, replacing animal rennet. The aim of this work was to study the changes that take place in free amino acids during the ripening of a goat's milk cheese (Murcia al Vino) manufactured with plant coagulant (PC) or animal rennet (AR). RESULTS: The total free amino acid (TFAA) concentration increased during ripening, with Ile, Val, Ala, Phe, Gaba, Arg and Lys representing more than 50% of the TFAA content at 60 days in both types of cheese. The TFAA concentration was significantly higher in cheeses made with PC (854 mg 100 g?1 total solids (TS)) than those made with AR (735 mg 100 g?1 TS). The concentration of most free amino acids, especially His, Ser, Gln, Thr, Ala, Met and Ile, was higher in the PC cheese. CONCLUSION: Cheese made using PC as coagulant presented higher contents of free amino acid throughout the ripening period than cheese made using AR. Therefore we can conclude that the use of PC to produce Murcia al Vino goat's cheese would accelerate the ripening process as a result of increased cyprosin proteolytic activity. Copyright © 2011 Society of Chemical Industry  相似文献   

17.
Powdered plant coagulant obtained from the cardoon flowers ( Cynara cardunculus ) was compared with calf rennet for the manufacture of traditional raw goats' milk cheese, by determining differences in the profiles of the amino acids throughout the ripening period. Derivatisation with o -phtaldialdehyde and a C18 column were used for chromatographic separations. In order to establish the relationships between the different variables and to detect the most important causes of variability, principal component analysis was applied to the free amino acids data, which reduced to two dimensions where cheese samples from 2 to 60 days and cheeses from 90 to 120 days were distributed dependently of ripening time and coagulant used. Leu, Val, Lys, Gly, Tyr and Asp were correlated with PC1, which separated the samples according to their ripening time. Arg, His, Trp, Ser and Thr were correlated with PC2, which separated the samples according to the coagulant used.  相似文献   

18.
This study was undertaken to evaluate the effect of lamb rennet paste containing probiotic strains on proteolysis, lipolysis, and glycolysis of ovine cheese manufactured with starter cultures. Cheeses included control cheese made with rennet paste, cheese made with rennet paste containing Lactobacillus acidophilus culture (LA-5), and cheese made with rennet paste containing a mix of Bifidobacterium lactis (BB-12) and Bifidobacterium longum (BB-46). Cheeses were sampled at 1, 7, 15, and 30 d of ripening. Starter cultures coupled with probiotics strains contained in rennet paste affected the acidification and coagulation phases leading to the lowest pH in curd and cheese containing probiotics during ripening. As consequence, maturing cheese profiles were different among cheese treatments. Cheeses produced using rennet paste containing probiotics displayed higher percentages of αS1-I-casein fraction than traditional cheese up to 15 d of ripening. This result could be an outcome of the greater hydrolysis of α-casein fraction, attributed to higher activity of the residual chymosin. Further evidence for this trend is available in chromatograms of water-soluble nitrogen fractions, which indicated a more complex profile in cheeses made using lamb paste containing probiotics versus traditional cheese. Differences can be observed for the peaks eluted in the highly hydrophobic zone being higher in cheeses containing probiotics. The proteolytic activity of probiotic bacteria led to increased accumulation of free amino acids. Their concentrations in cheese made with rennet paste containing Lb. acidophilus culture and cheese made with rennet paste containing a mix of B. lactis and B. longum were approximately 2.5 and 3.0 times higher, respectively, than in traditional cheese. Principal component analysis showed a more intense lipolysis in terms of both free fatty acids and conjugated linoleic acid content in probiotic cheeses; in particular, the lipolytic pattern of cheeses containing Lb. acidophilus is distinguished from the other cheeses on the basis of highest content of health-promoting molecules. The metabolic activity of the cheese microflora was also monitored by measuring acetic, lactic, and citric acids during cheese ripening. Cheese acceptability was expressed for color, smell, taste, and texture perceived during cheese consumption. Use of probiotics in trial cheeses did not adversely affect preference or acceptability; in fact, panelists scored probiotic cheeses higher in preference over traditional cheese, albeit not significantly.  相似文献   

19.
To determine the influence of milk preacidification with CO(2) on Cheddar cheese aging and proteolysis, cheese was manufactured from milk with and without added CO(2). The experiment was replicated 3 times. Carbon dioxide (approximately 1600 ppm) was added to the cold milk, resulting in a milk pH of 5.9 at 31 degrees C in the cheese vat. The starter and coagulant usage rates were equal for the control and CO(2) treatment cheeses. The calcium content of the CO(2) treatment cheese was lower, but no difference in moisture content was detected. The higher CO(2) content of the treatment cheeses (337 vs. 124 ppm) was maintained throughout 6 mo of aging. In spite of having almost one and a half times the salt-in-moisture, proteolysis as measured by pH 4.6 and 12% trichloroacetic acid soluble nitrogen expressed as percentages of total nitrogen, was higher in the CO(2) treatment cheeses throughout aging. The ratio of alpha(s)-casein (CN) to para-kappa-CN decreased faster in the CO(2) treatment cheeses than in the control cheeses, especially before refrigerated storage. No difference was detected in the ratio of beta-CN to para-kappa-CN between the control and CO(2) treatment cheeses. Intact alpha(s)- and beta-CN were found in the expressible serum (ES) from the CO(2) treatment cheese as well as alpha(s1)-I-CN, but they were not detected in the ES from the control cheese. No CN was detected in the ES from the curd before the salting of either the control or CO(2) treatment cheese. Higher proteolysis in the cheese made from milk preacidified with CO(2) may have been due to increased substrate availability in the water phase or increased chymosin activity or retention in the cheese.  相似文献   

20.
In this work, we assessed the influence of coagulant residual activity and primary proteolysis on Cremoso Argentino cheese melting properties. For that purpose, we made Cremoso soft cheeses using different amounts of coagulant, and also obtained samples in which milk-clotting enzyme was inactivated. Primary proteolysis correlated with residual activity of coagulant in early stages of cheese ripening; however, it was similar in all cheeses after 30 days. The hydrolysis of caseins did not significantly affect the melting ability of the cheeses, expressed as the area increase after heating samples under standardized conditions. Samples with similar proximate composition showed some changes in meltability; those seemed related to pH evolution during ripening.  相似文献   

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