مقایسه اثر اسانس پونه‌سای انبوه (nepeta glomerulosa) و نانوامولسیون آن بر ویژگی‌های کیفی سس مایونز

هدف از این پژوهش بررسی اثر اسانس و نانوامولسیون پونه‌سای انبوه (nepeta glomerulus) به‌عنوان یک نگهدارنده طبیعی در حفظ کیفیت سس مایونز پرچرب طی 6 هفته نگهداری در دمای ºc 35 بود. نانوامولسیون این اسانس به کمک انرژی فراصوت آماده و مشخصات فیزیکی آن اندازه‌گیری شد. سپس 0.5 درصد وزنی وزنی از اسانس و نانوامولسیون جایگزین روغن سس مایونز شد و عملکرد آن بر کیفیت شیمیایی (شاخص پراکسید، مواد واکنش‌دهنده با تیوباربیتوریک اسید، ph و اسیدیته)، میکروبی (باکتری‌های مقاوم به اسید، کپک و مخمر) و حسی سس مایونز با نگهدارنده‌های شیمیایی (bht و ترکیب بنزوات سدیم سوربات پتاسیم) مقایسه شد.1,8-cineole (26.9 %)، α pinene (7.3 %) و limonene (6.8 %) ترکیبات غالب اسانس پونه‌سای انبوه بودند. میانگین اندازه ذرات، شاخص چندپراکندگی و ویسکوزیته این نانوامولسیون به ترتیب nm 191.95، 0.225 و cp 1.03 بود. افزودن نانوامولسیون و اسانس پونه‌سای انبوه به طور معنی‌داری پایداری اکسایشی سس مایونز را نسبت به نمونه‌ی شاهد افزایش داد و تفاوت معنی‌داری بین عملکرد bht و اسانس پونه‌سای انبوه (خالص و امولسیون‌شده) دیده نشد (0.05

comparing the effect of nepeta glomerulosa essential-oil and its nanoemulsion on quality properties of mayonnaise

introduction: mayonnaise is known as a popular sauce around the world. however due to the high-fat content, it is susceptible to oxidative degradation. although the use of synthetic antioxidants is common to delay the oxidation process in food products, there is a general desire to replace chemical food additives and preservatives with natural ones nepeta glomerulosa is a species found in iran, especially in fars province. nepeta l. genus shows good bioactivity, related to terpenoid compounds, phenols, and flavonoids. plant essential oils are volatile oily liquids obtained from various aromatic plants, most of which are generally recognized as safe (gras). in recent years, essential oils have received much attention as suitable additives with antimicrobial and antioxidant potential. however, they are volatile, have a strong smell and taste as well as their water solubility is poor. moreover, they are also sensitive to environmental stress. therefore, the use of these compounds as natural preservatives has faced serious challenges in the food industry. encapsulation is a suitable way to overcome this challenge. one of the ways of encapsulation which is the preparation of nanodispersions and nanoemulsions can be considered one of the simplest and the most cost-effective techniques for encapsulating bioactive compounds. oil-in-water nanoemulsions consist of small oil droplets (20-200 nm) dispersed in a continuous aqueous phase, and each oil droplet is covered by a thin layer of emulsifier molecules. nanoemulsions have a higher surface area due to smaller particle size as compared to conventional emulsions was exerted their bioactivity at lower essential oil concentrations. thus, the current work aims to compare the effect of nepeta glomerulosa essential oil (pure and nanoemulsified) and chemical preservatives on the chemical, microbial and sensory properties of the high-fat mayonnaise during 6 weeks of storage at 35 ºc.materials and methods: the aerial parts of nepeta glomerulosa were collected from abadeh (fars, iran) and dried in shade room temperature (25 ± 5 ºc), ground, and passed through a sieve with a mesh of 400 micrometers. the essential oil of nepeta glomerulosa was extracted based on hydro-distillation using clevenger. a gas chromatography-mass spectroscopy (gc/ms) method was applied to identify the volatile compound of the essential oil. the nanoemulsion of nepeta glomerulosa essential oil was prepared by the ultrasound cavitation method. this nanoemulsion consisted of essential oil (10% w/w), tween 80 (2% w/w), and distilled water (88% w/w). the mean particle size and polydispersity index (pdi) were determined by dynamic light scattering. the formulation of mayonnaise samples was as follows: soybean oil without antioxidants (70%), egg yolk (10%), vinegar (12%), salt (1%), sugar (2%), mustard (0.25%), xanthan and guar (0.75%), lemon juice (4%). to investigate the preservative effect of the natural compounds, soy oil of the mayonnaise was substituted by 0.5 %w/w of the nepeta glomerulosa essential oil or its nanoemulsion. oxidative stability of mayonnaise samples was measured based on peroxide value (pv) and reactive substances with thiobarbituric acid (tbars). the acidity and ph of samples were also determined. according to the iranian national standard for mayonnaise, acid-resistant bacteria, heterofermentative lactic acid bacteria, escherichia coli mold, yeast content, and salmonella were evaluated. a sensory evaluation test was conducted based on a five-point hedonic scale (flavor, texture, and color). the weighted average scores of color, texture, and flavor were considered as the overall acceptance score. all experiments were conducted in triplicate and the data were analyzed by a general linear model anova (p < 0.05). the difference between the significant mean was tested using the tukey multiple comparison test. statistical analysis was performed using spss software.