بررسي تاثير غلظت هاي مختلف ژل آلوئه ورا و نوع روش توليد بر خصوصيات فيزيكي، حسي و ميكروبي خمير خرما

The Effect of Different Concentrations of Aloe vera Gel and Production Method on the Physical, Sensory and Microbial Properties of Date Paste

ﺧﻤﯿﺮ ﺧﺮﻣﺎ ﯾﮑﯽ از ﻓﺮآورده ﻫﺎي ﻣﻬﻢ ﺧﺮﻣﺎﺳﺖ ﮐﻪ در ﺳﺎلﻫﺎي اﺧﯿﺮ ﮐﺎرﺑﺮدﻫﺎي ﺑﺴﯿﺎري در ﺻﻨﻌﺖ ﻏﺬا ﭘﯿﺪاﮐﺮدهاﺳﺖ. در اﯾﻦ ﭘﮋوﻫﺶ، ﺗﺎﺛﯿﺮ ﻏﻠﻈﺖﻫﺎي ﻣﺨﺘﻠﻒ ژل آﻟﻮﺋﻪورا )0، 10، 25 و 50 درﺻﺪ( ﺑﺮ ﺧﺼﻮﺻﯿﺎت ﻓﯿﺰﯾﮑﯽ، ﺣﺴﯽ و ﻣﯿﮑﺮوﺑﯽ ﺧﻤﯿﺮ ﺧﺮﻣﺎ ﺗﻮﻟﯿﺪ ﺷﺪه ﺑﻪ دو روش اﺳﺘﻔﺎده از ﺑﺨﺎر آب و آب ﺟﻮش ﻣﻮرد ارزﯾﺎﺑﯽ ﻗﺮار ﮔﺮﻓﺖ. ﺧﺼﻮﺻﯿﺎت ﺧﻤﯽ ﺧﺮﻣﺎ ﻣﺎﻧﻨﺪ ﻣﺪت زﻣﺎن ﻣﺎﻧﺪﮔﺎري، درﺻﺪ رﻃﻮﺑﺖ، وﯾﮋﮔﯽﻫﺎي ﺣﺴﯽ، ﺧﻮاص رﺋﻮﻟﻮژﯾﮑﯽ وﮐﯿﻔﯿﺖ ﻣﯿﮑﺮوﺑﯽ)ﺷﻤﺎرش ﮐﻠﯽ ﺑﺎﮐﺘﺮﯾﺎﯾﯽ و ﮐﭙﮏ وﻣﺨﻤﺮ( در ﻃﯽ ﻣﺪت ﻧﮕﻬﺪاري در دﻣﺎي 5 درﺟﻪ ﺳﺎﻧﺘﯽﮔﺮاد )ﯾﺨﭽﺎل( ﺗﻌﯿﯿﻦ ﺷﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ ﺑﯿﺸﺘﺮﯾﻦ ﻋﻤﺮ ﻧﮕﻬﺪاري در ﺗﯿﻤﺎر ژل آﻟﻮﺋﻪوراي10 و 25 درﺻﺪ ﺗﻬﯿﻪ ﺷﺪه ﺑﺎ روش ﺑﺨﺎردﻫﯽ)ﺑﻪﺗﺮﺗﯿﺐ 10 و 9 روز( و ﮐﻤﺘﺮﯾﻦ ﻋﻤﺮ ﻧﮕﻬﺪاري در ﺗﯿﻤﺎرآﻟﻮﺋﻪ وراي 50 درﺻﺪ ﺗﻬﯿﻪ ﺷﺪه ﺑﺎ آب ﺟﻮش وﺷﺎﻫﺪ )2 روز( ﻣﺸﺎﻫﺪه ﺷﺪ. اﻓﺰاﯾﺶ ﻣﺪت زﻣﺎن ﻧﮕﻬﺪاري ﺗﺎﺛﯿﺮ ﻣﻌﻨﯽداري ﺑﺮ ﻣﯿﺰان رﻃﻮﺑﺖ ﻧﻤﻮﻧﻪﻫﺎي ﺧﻤﯿﺮ ﺧﺮﻣﺎ ﻧﺸﺎن ﻧﺪاد وﻟﯽ ﺑﺎ اﻓﺰاﯾﺶ درﺻﺪ آﻟﻮﺋﻪ ورا ﻣﯿﺰان رﻃﻮﺑﺖ ﺧﻤﯿﺮ ﺧﺮﻣﺎ در ﻫﺮ دو روش ﺗﻮﻟﯿﺪي اﻓﺰاﯾﺶ ﯾﺎﻓﺖ. وﯾﮋﮔﯽﻫﺎي ﺣﺴﯽ ﺗﺤﺖ ﺗﺎﺛﯿﺮ ﺗﯿﻤﺎرﻫﺎ ﻗﺮار ﮔﺮﻓﺘﻨﺪ و ﺑﯿﺸﺘﺮﯾﻦ اﻣﺘﯿﺎزات ﻣﺮﺑﻮط ﺑﻪ ﺗﯿﻤﺎر آﻟﻮﺋﻪ ورا 10 درﺻﺪ ﺗﻬﯿﻪ ﺷﺪه ﺑﺎ روش ﺑﺨﺎردﻫﯽ ﺑﻮد. ﻧﻤﻮﻧﻪﻫﺎي ﺗﻬﯿﻪ ﺷﺪه ﺑﺎ ﻏﻠﻈﺖﻫﺎي ﺑﯿﺸﺘﺮ آﻟﻮﺋﻪ ورا اﻣﺘﯿﺎزات ﺣﺴﯽ ﮐﻤﺘﺮي ﻧﺴﺒﺖ ﺑﻪ ﺳﺎﯾﺮ ﺗﯿﻤﺎرﻫﺎ درﯾﺎﻓﺖ ﮐﺮدﻧﺪ. ﻧﺘﺎﯾﺞ ﻣﺸﺨﺺ ﮐﺮد ﮐﻪ ﺑﺎ اﺳﺘﻔﺎده از ژل آﻟﻮﺋﻪ ورا ﺷﻤﺎرش ﮐﻠﯽ ﺑﺎﮐﺘﺮيﻫﺎ ، ﮐﭙﮏﻫﺎ و ﻣﺨﻤﺮﻫﺎ ﮐﺎﻫﺶ ﯾﺎﻓﺖ. ﺑﺎ اﻓﺰاﯾﺶ ژل آﻟﻮﺋﻪ ورا وﯾﺴﮑﻮزﯾﺘﻪ ﻧﻤﻮﻧﻪﻫﺎ ﮐﺎﻫﺶ ﯾﺎﻓﺖ. وﯾﺴﮑﻮزﯾﺘﻪ ﻧﻤﻮﻧﻪﻫﺎي ﺗﻬﯿﻪ ﺷﺪه ﺑﺎ ﺑﺨﺎر ﺑﯿﺸﺘﺮ از ﻧﻤﻮﻧﻪﻫﺎي ﺗﻬﯿﻪ ﺷﺪه ﺑﺎ آب ﺟﻮش ﺑﻮد. ﮐﻢ ﺗﺮﯾﻦ وﯾﺴﮑﻮزﯾﺘﻪ ﺑﻪ ﺗﯿﻤﺎر 50 درﺻﺪ آﻟﻮﺋﻪ ورا و آب ﺟﻮش اﺧﺘﺼﺎص داﺷﺖ. ﺑﻪ ﻃﻮر ﮐﻠﯽ ﻧﺘﺎﯾﺞ اﯾﻦ ﭘﮋوﻫﺶ ﻧﺸﺎن داد ﮐﻪ اﺳﺘﻔﺎده از ژل آﻟﻮﺋﻪورا در ﻏﻠﻈﺖﻫﺎي ﮐﻤﺘﺮ )ﺣﺪود 10 و 25 درﺻﺪ( ﺧﻮاص ﻓﯿﺰﯾﮑﯽ و ﺣﺴﯽ ﺧﻤﯿﺮ ﺧﺮﻣﺎ را ﺑﻬﺒﻮد ﻣﯽﺑﺨﺸﺪ و ﻣﯽﺗﻮاﻧﺪ ﻋﻤﺮ ﻧﮕﻬﺪاري ﺧﻤﯿﺮ ﺧﺮﻣﺎ را اﻓﺰاﯾﺶ دﻫﺪ.

Date paste is one of the important date by-products that has found many applications in the food industry in recent years.In this study, the effect of different concentrations of Aloe vera gel (0, 10, 25 and 50%) on the physical, sensory and microbial properties of date paste produced by two methods of using steam and boiling water were evaluated.Characteristics of date paste such as shelf life, moisture content, sensory properties, rheological properties and microbial quality (total bacterial count and mold and yeast) were determined during storage at 5 °C.The results showed that the maximum shelf life in 10 and 25% Aloe vera gel treatments prepared by steaming method (10 and 9 days, respectively) and the lowest shelf life in 50% Aloe vera treatment beyond prepared with boiling water and control (2 days) were observed. Increasing the storage time did not show a significant effect on the moisture content of date paste samples, but with increasing the percentage of Aloe vera, the moisture content increased in both methods. Sensory characteristics were affected by the treatments and the highest scores related to 10% Aloe vera treatment prepared by steaming method. Samples produced with higher concentrations of Aloe vera received lower sensory scores than other treatments. The results showed that using Aloe vera gel reduced the total counts of bacteria, molds and yeasts. By increasing Aloe vera gel, the viscosity of the samples decreased. The viscosity of samples prepared by steam was higher than the samples prepared by boiling water. The lowest viscosity was related to 50% Aloe veratreatment and boiling water.In general, the results of this study showed that the use of Aloe vera gel in lower concentrations (about 10 and 25%) improves the physical and sensory properties of date paste and can increase the shelf life of date paste.