A Welcome Message from The Editor

It is with profound pleasure that we write this editorial to welcome you to the new journal, “Pakistan Biomedical Journal” (PBMJ), an interdisciplinary international journal. PBMJ has successfully completed its first volume and now its the second volume. We greatly appreciate the response of scientists who have contributed previously and are still contributing to this new journal. The subject of the journal is interesting and we try to address the health related concerns of public and improve the understandingof scientific phenomenons by researchers. Research discoveries are happening at a fast pace, in all the fields and PBMJ provides an ideal forum for exchange of scientific knowledge in terms of full length papers, surveys, reviews, case studies, letters to editor and systematic analysis. PBMJ is committed to publishing all manuscripts receiving a high recommendation from reviewers. The intention of PBMJ is to create space for generation of new knowledge, debate, collaborations among national and international scientists. Our vision is to promote research that will be helpful for knowledge sharing, new discoveries, development of critical thinking among the upcoming scholars, guidance for policy makers, awareness among the concerned community and ultimately benefitting the general population in improving health and fitness at large. It is a matter of pride for us to haveexcellent editorial board members from renowned institutes. We aim to have the best standards of quality of the published manuscripts. With every issue, we are continuously trying to improve the standards. We look forward for more exciting researches and scientific studies from all over the world. We would like to extend a very warm welcome to the readers of PBMJ and hope you will join us as authors, reviewers and editors in future.

Impact of Dietary Fiber and Hydrocolloids on the Quality of Low Fat Cheddar Cheese

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.