Physicochemical, microbiological, and sensory characteristics of probiotic yogurt enhanced with Anethum graveolens essential oil

Abstract

In the present work, physicochemical, sensory characteristics and viability of Bifidobacterium bifidum and Lactobacillus casei of probiotic yogurt using dill (Anethum graveolens) essential oil (DEO) (50 and 100 ppm) were investigated at 4°C for 21 days. Alterations in amount of fat and protein of yogurt treatments during storage time were not significant. The viability of B. bifidum and L. casei increased up to the 2nd week of storage and then decreased by the end of the storage period. Generally, samples with incorporated 100 ppm DEO had the highest number of probiotic bacteria on the last day of storage, 7.81 and 7.92 CFU/g for L. casei and B. bifidum, respectively. pH and titratable acidity values were decreased and increased, respectively, over the time for all samples. Yogurt with incorporated 100 ppm DEO achieved higher sensory scores compared to other yogurt samples. Therefore, the current results confirmed that the addition of probiotic and DEO improved the physicochemical and sensory characteristics of yogurt. Practical Applications Yogurt undergoes sensory, chemical changes and microbial growth during refrigerated storage. Bifidobacterium bifidum and Lactobacillus casei are generally applied as probiotic species in milk products. Dill essential oil (DEO) is used in food industries to extend the shelf life of the foods with desired organoleptic properties. This work recommends that DEO can be successfully used as a safe and natural source in the production of probiotic yogurt.

Effect of Bunium persicum essential oil, NaCl, Bile Salts, and their combinations on the viability of Lactobacillus acidophilus in probiotic yogurt

“…Many ingredients have been added to yogurt in recent years, including Primula vulgaris (Lee et al, 2007), Mentha piperita, and Ziziphora clinopodioides (Sarabi-Jamab and Niazmand, 2009) to improve the nutritional, medicinal, and sensory properties and maintenance of yogurt. There are conflicting reports about the effecting of essential oils on the sensory properties so probiotic survival in yogurt, where some studies have shown a decrease in the sensory qualities of the yogurt (Moritz et al, 2015;Shahdadi et al, 2015), improved product properties sensory (Azizkhani and Parsaeimehr, 2018;Shahdadi et al, 2015), no adverse effect on probiotic activity (Azizkhani and Parsaeimehr, 2018;Sarabi-Jamab and Niazmand, 2009), and a negative impact on the activity and survival of probiotics (Azizkhani and Parsaeimehr, 2018). On the other side, the minimum inhibitory concentration (MIC) of plant essential oils against probiotics is high, while at the value of concentrations, the essential oils have inhibitory effects on pathogens.…”

Lactobacillus acidophilus and Anethum graveolens essential oil in Iranian cheese against Escherichia coli O157:H7

“…Results showed that carvone (48.73%) and α‐phellandrene (31.71%) were the main agents. As indicated previously, the main chemical compositions of DEO are carvone and limonene (54.2 and 15.6%, respectively) (Singh et al 2011) and Mehdizadeh et al (2019) concluded that α‐phellandrene and carvone are the major agents in DEO (40.22 and 37.65%, respectively) that have some antimicrobial characteristics 4,20 . The amount of these compositions is related to weather and soil type, plant age, herbal drying procedure and extraction procedure (Table 1).…”

“…Therefore, it is better to use probiotic products include 10 6 CFU/mL of these kinds of bacteria every day and should be used every day 3 . All products including probiotic bacteria are recognized as ‘functional products’, and some probiotic foods are achieving universality and appropriate all over the developed country 4 . In these days, functional foods are limited mostly to cheese, yogurt and fermented milk drinks incorporated with probiotic bacteria like bifidobacteria and lactobacilli 5 …”

“…Mehdizadeh et al (2018) concluded that L acidophilus reduced the E coli O157:H7 population 7 . The prevention of infection requires control measures at all stages of the food chain, from agricultural production on the farm to processing, manufacturing and preparation of foods in both commercial establishments and household kitchens 4 …”

“…Dunn et al (2016) reported the effect of plant‐derived volatile oils on viability and growth of some LABs 13 . Mehdizadeh et al (2019) concluded that the use of DEO causes a detectable diffusion of cytoplasmic ingredients, consists of permeation of potassium ions in the membrane, and leads to unalterable injury to E coli bacteria 4 . A graveolens generally recognized as dill is a yearly fragrant herb related to family Umbelliferae and is from West Asia and Mediterranean.…”