بررسی ویژگی‌های فیزیکی دانه ماشک گل ‌خوشه‌ای (vicia villosa) و بررسی اثر چربی‌گیری و تغییرات ph بر ویژگی‌های فیزیکوشیمیایی و عملکردی آرد حاصل از آن

نظر به اهمیت روز افزون نیاز به منابع پروتئینی جدید و کمبود منابع پروتئینی حیوانی، استفاده از منابع گیاهی مورد توجه است. هدف از این مطالعه معرفی پتانسیل‌های دانه ماشک گل ‌خوشه‌ای به‌عنوان یک منبع بومی و جدید پروتئینی بود. در این راستا ویژگی‌های فیزیکی دانه و ترکیب شیمیایی و پارامترهای رنگ آرد ماشک گل‌خوشه ای قبل و بعد از چربی‌گیری تعیین شد و تاثیر تغییر ph و چربی‎گیری بر ویژگی‎های عملکردی آرد حاصل مورد بررسی قرار گرفت. متوسط طول، عرض و ارتفاع دانه‎ها به‎ترتیب 5.4، 5.37 و 5.38 میلی‎متر و میانگین حسابی و هندسی قطر، ضریب کرویت و سطح به‎ترتیب 5.383، 5.383 میلی‎متر، 0.997 و 90.987 میلی‎متر مربع به‎دست آمد. میانگین دانسیته حقیقی، دانسیته توده و درصد تخلخل به‎ترتیب 1286.3 کیلوگرم بر متر مکعب، 788.8 کیلوگرم بر متر مکعب و 38.67 درصد بود. آرد ماشک گل خوشه‎ای کامل و چربی‎گیری شده به‎ترتیب دارای 28.3و 31.2 درصد پروتئین و همچنین 8.2 و 1.92درصد چربی بود. آرد چربی‎گیری شده *l بیشتر، a*وb* کمتری نسبت به آرد کامل داشت. اندیس حلالیت، ظرفیت جذب آب و همچنین روغن آرد ماشک گل خوشه‌ای کامل و بدون چربی به‌ترتیب 5.91 و 7.24، 132.95و193.69 و همچنین 85.07 و119.51درصد به‌دست آمد. حداقل غلظت ژل‌دهندگی، آرد چربی‌گیری شده کمتر از آرد کامل گزارش شد. چربی‌گیری آرد ماشک گل خوشه‌ای نیز موجب افزایش معنی‌دار (p <0.05) ظرفیت امولسیون‌کنندگی و پایداری امولسیون و همچنین ظرفیت کف‌کنندگی و پایداری کف شد. نتایج نشان داد تغییرات ph بر میزان حلالیت، ظرفیت کف‌کنندگی و پایداری کف و ظرفیت امولسیون‌کنندگی و پایداری امولسیون آرد ماشک گل خوشه‌ای به‌طور معنی‌داری (p <0.05) بود و با تغییر ph می‌توان مقادیر متفاوتی برای این ویژگی‌های عملکردی به‌دست آورد. با دور شدن از ph ایزوالکتریک ویژگی‌های عملکردی بهبود یافتند.

Evaluation the physical properties of Vicia Villosa seed and Study the effect of defatting and pH on the physicochemical and functional properties of its flour

Introduction: Due to increasing the demand for new sources of protein and the lack of animal protein sources, using and replacing of plant proteins is widely considered. The purpose of this study was to identify the potential of Vicia villosa flour as a native and novel source of protein. In this research, the physical properties of vicia villosa seed and chemical composition (protein, fat, ash, and carbohydrate and moisture contents) and color parameters of its full fat flour were determined and compared with defatted flour as well as the effect of defatting and pH on the functional  properties of full fat and defatted vicia villosa  flour were investigated.   Materials and methods: Vicia Villosa seed was obtained from the local market in Chaharmahal and Bakhtiari province and was cleaned, skinned and, milled. Half of the full fat flour was defatted. The obtained flours were then refrigerated at 4°C for further analysis. Physical properties of the seed including size, dimension, mass, true and bulk density as well as porosity were measured using standard methods and calibrated equipments. Chemical composition of both the seed and skinned seed’s flour (moisture content, fat, protein and ash) were determined using standard methods (AACC, 2003). The carbohydrate content of the samples was determined by subtraction of the sum of other compositional substances from 100. Color properties, protein solubility, water soluble index, water and oil absorption capacity, least gelation concentration, foaming capacity and emulsifying capacity and emulsion stability and foaming stability were also measured for the full fat and defatted Vicia Villosa flours.   Results and discussion: The results obtained from the measurement of physical properties for the Vicia Villosa seed showed that length, width, and thickness of the seeds were 5.4 mm, 5.37 mm, and 5.38 mm respectively. The surface area of seeds was found to be 90.98 mm2. True density, bulk density, and porosity of samples were found to be 1286.3 mm3, 788.8 mm3, and 38.67%, respectively. The amount of protein for full fat and defatted Vicia Villosa flour was 28.3% and 31.02%, respectively. L* was measured for the obtained flours and the highest L* was  belonged to defatted Vicia Villosa flour, probably due to the removal of the seed shells in the solvent removal stage. Defatting of flour would result in brighter and increase in protein content of flour. The test on protein solubility showed the high dependency of this parameter to pH of the flour proving the U form dependency in the pH range of 212. At an isoelectric point of 4.5, the minimum solubility of existing proteins was shown. Water and oil absorption capacity of Full fat were 1.33± 0.4 and 0.85± 0.07 and Defatted Vicia Villosa flour,were 1.94± 0.2 and 1.19± 0.1 respectively (grams of water or oil per grams of the sample). Furthermore, at pH= 4.5, the emulsion and foaming capacity decrease due to its proximity to the isoelectric point. It is noteworthy that in isoelectric pH, the highest foaming stability and the lowest emulsion stability were observed. In addition, the results showed that pH and defatting conditions have a significant effect on functional properties that can be created by changing these parameters, flours, and products with various characteristics. The results showed that changes in pH and defatting process affected  the  solubility, water and fat absorption, least gelation concentration, foaming capacity and emulsion  capacity of flour, so that by defatting and changing pH, functional properties improved significantly.