بررسی تاثیر ساکارز با سطح مناسب شیرین بیان به عنوان شیرین کننده بومی ایران بر کیفیت بستنی

زمینه مطالعاتی: بستنی پرطرفدارترین محصول در رده دسرهای لبنی است و مصرف بالای ساکارز باعث بیماری‌های قلبی-عروقی، چاقی و دیابت می‌شود که با جایگزینی ساکارز با عصاره شیرین‌بیان می‌توان این مشکلات را کاهش داده و محصولی سالم و ایمن تولید کرد. هدف: استخراج عصاره شیرین بیان به روش فراصوت و یافتن غلظت مناسبی از پودر عصاره شیرین‌بیان برای استفاده در فرمولاسیون بستنی به منظور کاهش ساکارز، مورد بررسی قرار گرفت. روش کار: غلظت‌های مختلف عصاره شیرین‌بیان (0.5، 1، 1.25، 1.5، 1.75 و 2%) همراه با شکر به بستنی افزوده شد و ویژگی‌های فیزیکی شیمیایی بستنی شامل ph، وزن مخصوص، ویسکوزیته، ضریب افزایش حجم، ماده جامد کل، زمان اولین قطره ذوب، رنگ سنجی و ارزیابی حسی مورد بررسی قرار گرفت. نتایج: ویژگی‌های فیزیکی شیمیایی بستنی نشان داد با جایگزینی شیرین‌بیان در بستنی میزان ph بطور معنی‌داری کاهش یافت و کمترین میزان ph در نمونه حاوی 2% شیرین‌بیان (6.38) دیده شد و جایگزینی تا غلظت 1.5 درصد منجربه افزایش ویسکوزیته و کاهش مواد جامد کل شد. همچنین تیمار حاوی 2% شیرین‌بیان با دارا بودن بالاترین میزان ضریب افزایش حجم (42.60%) دارای طولانی‌ترین زمان اولین قطره ذوب (11 دقیقه) بود. با افزایش غلظت شیرین‌بیان، شاخص روشنایی کاهش یافت و مقادیر a، b نمونه‌ها افزایش یافت. همچنین بستنی حاوی 1% شیرین‌بیان از دید ارزیابان دارای پذیرش حسی بالاتری بود. نتیجه‌گیری نهایی: میتوان تا غلظت 1% عصاره شیرین‌بیان را برای جایگزینی ساکارز در بستنی مطلوب انتخاب کرد.

investigating the effect of sucrose with a suitable level of licorice as a native iranian sweetener on the quality of ice cream

introduction: ice cream is the most popular dessert in the category of dairy products. the definition of ice cream varies from country to country (goff et al., 2013). according to the definition of iranian national standard no. 2450, ice cream is a nutritious product that is prepared by freezing and aerating a homogeneous and pasteurized mixture of ingredients such as milk, fat, sugar, additives, and other optional ingredients in order to increase the quality and nutritional value of ice cream. the desired sweetness of ice cream is approximately equivalent to 13 to 16% of sucrose in the composition of 36 to 38% of total solids. different types of sugar do not have the same sweetness, sweetness cannot be precisely defined and measured (goff et al., 2013). high sucrose consumption causes cardiovascular diseases, obesity, and diabetes (ozdemir et al., 2015). therefore, much effort has been focused on using natural sweeteners in ice cream production (alizadeh et al., 2014). sugar plays many roles in food. its most obvious function is sweet sugar, but it also helps improve flavor performance and affects mouthfeel and textural properties. all sweeteners can be used only as partial replacements for sugar since complete replacement significantly changes the structural properties (goff et al., 2013). the genus glycyrrhiza is a well-known traditional medicinal plant that grows in several regions of the world. the stolons and roots of these plants have been used in traditional medicine for more than 4000 years. rhizomes and roots are the most important medicinal parts of licorice, which have been reported alone or in combination with other plants to treat many gastrointestinal disorders (such as peptic ulcer, hyperplasia, flatulence and colic), respiratory disorders such as cough, asthma, tonsillitis, and it is used for sore throat, epilepsy, fever, impotence, paralysis, rheumatism, leukorrhea, psoriasis, prostate cancer, malaria, bleeding diseases and (öztürk et al., 2018). licorice is mainly used as a sweetener because it is 50 times sweeter than sucrose and also has medicinal properties (bahmani et al., 2015). licorice is widely used in the food industry as a sweetener, flavor enhancer, and flavor modifier. therefore, licorice extract is usually used in sweet foods such as sweet snacks, ice cream and syrup to increase their sweetness (alfaumi et al., 2020). material and methods: the dried licorice root was cut into small pieces (1-0.5 cm in diameter and 1-0.5 cm in length). the dried roots were ground using a laboratory mill and after passing through a sieve (mesh 35) they were stored in polyethylene bags at -18°c (shabkhiz et al., 2016). for the preparation of extract, 25 grams of powdered licorice root mixed with 50% (v/v) ethanol-water solvent at a ratio of 1:5 and subjected to 37 khz ultrasound waves for 30 minutes at a temperature of 45°c and after filtering with whatman no. 1 paper, then the solution was evaporated at 45°c in an oven and after freeze drying, the resulting powder was homogenized and stored in a dark container at -18°c until the experiments were carried out and for the preparation of different licorice extracts (0.5, 1, 1.25, 1.5, 1.75, and 2%) was used as a substitute for sucrose in ice cream formulation. ice cream formulation based on 7% fat, sweetness equivalent to 15% sucrose (mixture of sucrose and licorice extract), 9% dry matter fat-free milk, 0.1% vanilla, and 0.3% salep, treatment, and control samples are prepared. for the preparation of ice cream first, the milk was heated to a temperature of 40-45 degrees celsius, then the milk and cream were homogenized for one minute, sucrose was added to the mixture along with other dry components including licorice, milk powder, salep and mixed for 5 minutes with a mechanical stirrer at 70 rpm. the resulting mixture was pasteurized for 30 minutes at 70°c in a bain-marie and finally cooled to 5°c with the help of antifreeze (ice and salt).