Improving Texture and Flavor of Reduced-Fat Cheddar Cheese Using an Exopolysaccharide-Producing Culture and Ultrafiltration

<p>The texture of reduced-fat Cheddar cheese is typically rubbery, dry and grainy. In previous studies (Awad et al., 2005a; b; Hassan et al., 2005), an exopolysaccharide-(EPS) producing culture improved textural, melting and viscoelastic properties of reduced-fat Cheddar cheese. However, this EPS-positive cheese developed bitterness after 2 to 3 months of ripening due to increased residual chymosin activity. We hypothesized that the reduced amount of chymosin needed to coagulate ultrafiltered (UF) milk might result in reduced residual chymosin activity and bitterness in cheese. The objectives of this study were to improve the texture and flavor of reduced-fat Cheddar cheese using a combination of EPS-producing culture and UF. Reduced-fat Cheddar cheeses were manufactured with EPS-producing and non-producing cultures using skim milk or UF skim milk (1.2x) adjusted to a casein: fat ratio of 1.35. The EPS-producing culture increased yield, moisture in nonfat substance, and residual chymosin activity in reduced-fat Cheddar cheese. In addition, EPS-positive cheese was softer, and less gummy and rubbery than the EPS-negative cheese. The viscoelastic moduli were higher in 1 day old EPS-negative reduced-fat cheese than in the EPS-positive cheese. During ripening, whereas the viscoelastic moduli increased in the EPS-positive cheese, they decreased in the EPS-negative one. At day 1, the creep/recovery test showed that EPS-positive cheese was less rigid and more deformable than EPS-negative cheese. Lower (P≤0.05) residual chymosin activity was found in cheese made from UF milk than that in cheese made from control milk. The low UF concentration level (1.2x) did not affect the textural characteristics of cheese. Panelists reported that UF-EPS-positive cheese was less (P≤ 0.05) bitter than EPS-positive cheese made from control milk. Using an EPS-producing culture improved the texture and UF milk (1.2x) reduced bitterness in reduced-fat Cheddar cheese, which has beneficial commercial implications in the manufacture of this type of cheese.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Thesis - University Access Only

Discipline thesis:degree_discipline

Dairy Science

Year dc:date.available

2006

Author dc:creator

• Agrawal, Panna

Contributors dc:contributor

• Ashraf N. Hassan

• Dairy Science

Statement dc:rights

• <p>In Copyright - Non-Commercial Use Permitted<br /><a href="http://rightsstatements.org/vocab/InC-NC/1.0/">http://rightsstatements.org/vocab/InC-NC/1.0/</a></p>

Language dc:language

en

Repository record dc:identifier

https://openprairie.sdstate.edu/etd/1526

OAI identifier oai:identifier

oai:openprairie.sdstate.edu:etd-2530