بررسي تاثير استفاده از صمغ كنجاك به عنوان جايگزين چربي بر ويژگي هاي فيزيكوشيميايي، رئولوژيكي و حسي خامه كم چرب

Study the Effect of Konjac Gum as a Fat Substitute on the Physico- Chemical, Rheological and Sensory Properties of Low-fat Cream

اﯾﻦ ﻣﻄﺎﻟﻌﻪ ﺑﻪ ﻣﻨﻈﻮر ﺑﺮرﺳﯽ ﺗﺎﺛﯿﺮ اﺳﺘﻔﺎده از ﺻﻤﻎ ﮐﻨﺠﺎك ﺑﻪ ﻋﻨﻮان ﺟﺎﯾﮕﺰﯾﻦ ﭼﺮﺑﯽ ﺑﺮ وﯾﮋﮔﯽﻫﺎي ﻓﯿﺰﯾﮑﻮﺷﯿﻤﯿﺎﯾﯽ، رﺋﻮﻟﻮژﯾﮑﯽ و ﺣﺴﯽ ﺧﺎﻣﻪ ﮐﻢ ﭼﺮب اﻧﺠﺎم ﮔﺮدﯾﺪ. ﺑﺪﯾﻦ ﻣﻨﻈﻮر ﻣﻘﺎدﯾﺮ ﻣﺨﺘﻠﻒ ﺻﻤﻎ ﮐﻨﺠﺎك در ﻏﻠﻈﺖﻫﺎي 0/25، 0/5 و 0/75 درﺻﺪ ﺑﻪ ﺧﺎﻣﻪ اﻓﺰوده ﮔﺮدﯾﺪ و ﻣﯿﺰان ﭼﺮﺑﯽ ﺧﺎﻣﻪ از 30% ﺑﻪ 20% ﮐﺎﻫﺶ ﯾﺎﻓﺖ. در اﯾﻦ ﭘﮋوﻫﺶ آزﻣﻮنﻫﺎي رﻃﻮﺑﺖ، pH، اﺳﯿﺪﯾﺘﻪ، ﺑﺎﻓﺖ، وﯾﺴﮑﻮزﯾﺘﻪ ﻇﺎﻫﺮي، ﭘﺎﯾﺪاري اﻣﻮﻟﺴﯿﻮن، ارزﯾﺎﺑﯽ رﻧﮓ و ارزﯾﺎﺑﯽ ﺣﺴﯽ ﺻﻮرت ﭘﺬﯾﺮﻓﺖ و ﺑﺎ دو ﻧﻤﻮﻧﻪ ﺧﺎﻣﻪ ﺷﺎﻫﺪ ﮐﻢ ﭼﺮب )20% ﭼﺮﺑﯽ و ﺑﺪون ﺻﻤﻎ( و ﺷﺎﻫﺪ ﭘﺮ ﭼﺮب )30% ﭼﺮﺑﯽ( ﻣﻘﺎﯾﺴﻪ ﮔﺮدﯾﺪ. ﻧﺘﺎﯾﺞ اﯾﻦ ﺗﺤﻘﯿﻖ ﻧﺸﺎن داد ﮐﻪ ﺟﺎﯾﮕﺰﯾﻨﯽ ﺻﻤﻎ ﮐﻨﺠﺎك ﺑﺎﻋﺚ ﮐﺎﻫﺶ ﻣﻌﻨﯽدار ﻣﯿﺰان رﻃﻮﺑﺖ، اﺳﯿﺪﯾﺘﻪ و ﻣﯿﺰان آب اﻧﺪاﺧﺘﮕﯽ ﻧﻤﻮﻧﻪﻫﺎي ﺧﺎﻣﻪ ﻧﺴﺒﺖ ﺑﻪ ﻧﻤﻮﻧﻪ ﺷﺎﻫﺪ ﮐﻢﭼﺮب ﺷﺪه اﺳﺖ. ﺳﻔﺘﯽ ﺑﺎﻓﺖ و وﯾﺴﮑﻮزﯾﺘﻪ ﻇﺎﻫﺮي ﺑﺎ اﻓﺰاﯾﺶ ﺻﻤﻎ، ﺑﻪ ﻃﻮر ﻣﻌﻨﯽداري اﻓﺰاﯾﺶ ﭘﯿﺪا ﮐﺮده ﮐﻪ در اﯾﻦ ﻣﯿﺎن، ﻧﻤﻮﻧﻪ ﺣﺎوي 0/5 درﺻﺪ ﮐﻨﺠﺎك ﻣﺸﺎﺑﻪ ﻧﻤﻮﻧﻪ ﺷﺎﻫﺪ ﭘﺮﭼﺮب ﺑﻮد. ﻫﻤﭽﻨﯿﻦ ﻧﺘﺎﯾﺞ ارزﯾﺎﺑﯽ ﺣﺴﯽ ﻧﺸﺎن داد ﮐﻪ ارزﯾﺎﺑﺎن ﺣﺴﯽ ﺗﻔﺎوﺗﯽ ﺑﯿﻦ ﻧﻤﻮﻧﻪﻫﺎي ﺣﺎوي ﮐﻨﺠﺎك و ﺷﺎﻫﺪ ﭘﺮﭼﺮب ﻗﺎﺋﻞ ﻧﺸﺪﻧﺪ. ﺑﻨﺎﺑﺮاﯾﻦ ﻣﯽﺗﻮان ﻧﺘﯿﺠﻪ ﮔﺮﻓﺖ ﮐﻪ ﺻﻤﻎ ﮐﻨﺠﺎك در ﺳﻄﺢ 0/5 درﺻﺪ ﺑﻪ دﻟﯿﻞ دارا ﺑﻮدن ﺧﺼﻮﺻﯿﺎت ﻓﯿﺰﯾﮑﻮﺷﯿﻤﯿﺎﯾﯽ ﻣﻄﻠﻮب و اﯾﺠﺎد ﺑﺎﻓﺖ و ﻃﻌﻤﯽ ﻗﺎﺑﻞ ﻗﺒﻮل ﻣﯽﺗﻮاﻧﺪ ﺑﻪ ﻋﻨﻮان ﺟﺎﯾﮕﺰﯾﻦ ﭼﺮﺑﯽ ﺑﺮاي ﺗﻬﯿﻪ ﺧﺎﻣﻪ ﮐﻢﭼﺮب ﻣﻮرد اﺳﺘﻔﺎده ﻗﺮار ﮔﯿﺮد..

This study was carried out to determine the effect of using konjac gum as a fat substitute on the physico-chemical, rheological and sensory properties of low-fat cream. For this purpose, different concentrations (0.25, 0.5 and 0.75%) of konjac gum were added to the cream, and the amount of cream fat decreased from 30% to 20%. In this study, moisture, pH, acidity, texture, apparent viscosity, emulsion stability, color evaluation and sensory evaluation were investigated and compared with low fat (with 20% fat and without gum) and high fat (with 30% fat) cream as control samples. The results showed that the replacement of konjac gum significantly caused a decrease in the moisture content, acidity and syneresis amount compared to the low-fat control sample. Texture and apparent viscosity significantly increased with increasing gum, while the sample containing 0.5% konjac was similar to high fat control sample. Also, the results of sensory evaluation showed that panelists did not differentiate between samples containing konjac and high fat control sample. Therefore, it can be concluded that konjac gum at 0.5% can be used as a fat substitute for the preparation of lowfat cream due to its favorable physicochemical properties and acceptable texture and flavor.