Impact of dietary fiber and hydrocolloids on the quality of low fat cheddar cheese

Abstract

Low fat Cheddar cheese is the demand of present era, but lacks the quality and functionality of cheese. The quality defects can be overcome through various techniques including the addition of hydrocolloids and dietary fibers as fat replacers. The present study was aimed to produce low fat cheddar cheese using hydrocolloids (xanthan gum and guar gum) and dietary fibers (Inulin and resistant starch) in different combinations to improve its quality and functionality. Study was performed in three phases. In 1st phase, different levels of hydrocolloids and dietary fibers were evaluated to screen out the best levels on the basis of textural, functional and sensory parameters. In 2nd phase, the selected levels from 1st phase were evaluated in different combinations to select the best ones. In 3rd phase, the selected hydrocolloids and fibers and their combinations along with positive and negative controls were used to manufacture low fat Cheddar cheese. The cheese samples were ripened for 3 months and evaluated for physico-chemical, functional and textural profile, proteolysis, organic acids contents, scanning electron microscopy and descriptive sensory perception. Different levels of hydrocolloids and dietary fibers in phase-I showed significant effect (p<0.05) for all the parameters. Cheese hardness decreased on increasing the level of gums and increased on increasing the level of dietary fibers. Melt-ability and flow-ability showed the inverse relation to hardness. Maximum sensory scores were attained by xanthan gum @ 0.15%, guar gum @ 0.45%, inulin @ 0.5% and resistant starch @ 1% and were screened out for next phase. The combinations depicted significant impact on the parameters studied. Cheese having xanthan gum and Inulin were harder with least melt-ability and flow-ability as compared to others. On the basis of functional, textural and sensory parameters, samples XGS (xanthan gum, guar gum and resistant starch), GIS (guar Gum, inulin and resistant starch) and XGIS (xanthan gum, guar gum, inulin and resistant starch) were selected. In final phase, hydrocolloids and dietary fibers significantly (p<0.05) affected the physico-chemical and functional parameters of cheese. Maximum moisture (44.70%) was recorded in GC and the lowest (38.33%) in C+ve (full fat cheese). Maximum protein (29.24%) was recorded in C-ve and the lowest (26.81%) in C+ve due to more fat content. All the low fat cheeses have more pH and less acidity. pH decreased from 5.47-5.27 as a function of storage. GIS had maximum melt-ability (66.28 mm) and flow-ability (24.13) while negative control showed the least melt-ability (52.65 mm) and flow-ability (18.85) values. GC has hardness equal to full fat cheese and owing to more moisture to protein ratio, had more proteolysis, which was minimum in control samples. All the low fat cheese samples differed significantly (p<0.05) in organic acids content except formic acid and the concentrations of organic acids increased during ripening. Cheeses with different hydrocolloids and fibers showed different behavior in scanning. After 90 days of storage, less compact structure and more open spaces were visualized. On descriptive sensory evaluation, low fat cheese samples showed significant (p<0.05) differences for all the parameters. Scores for most of odor and flavor traits increased during ripening. However, for some texture attributes, declining trend was observed. Overall full fat cheese gained the maximum scores for all attributes. The principal components analysis and hierarchical cluster analysis also depicted the substantial discrepancy for sensory perception among the various low fat chees samples. Hence, from the study it concluded that low fat Cheddar cheese can effectively be manufactured by using guar gum alone and combination of guar gum, inulin and resistant starch with quality and functionality comparable to its full fat counterpart.