Different Ultrasound Exposure Times Influence the Physicochemical and Microbial Quality Properties in Probiotic Goat Milk Yogurt

Abstract

Despite goat milk having health benefits over cow milk, goat milk yogurt (GY) presents low consistency and viscosity, which reduces its overall acceptability by the consumer. Thus, new innovative methods can be an alternative to improve the quality of GY. Hence, this study aimed to investigate the effect of ultrasound (US) treatment with different sonication times on quality parameters of probiotic GY during refrigerated storage. US treatment was conducted at 20 KHz for 3, 6, and 9 min in yogurt. Lactobacillus bulgaricus and Lactobacillus acidophilus LA-5 were sensitive to US treatment, presenting a decrease in the yogurts stocked. This loss of viability led to reduced post-acidification due to smaller lactose metabolization in yogurt samples submitted to the US. Among tested treatments, the application of 6 min enhanced the apparent viscosity and consistency index of GY yogurts. In addition, this time also reduced tyramine and total biogenic amine (BAs) content. These findings suggest that 6 min of sonication is a promising way to improve the rheological properties and reduce the acidity and BAs content in GY. Further studies should be performed to optimize the US setting conditions to preserve the probiotic culture viability in yogurts.

Effect of sonication conditions: Time, temperature and amplitude on physicochemical, textural and sensory properties of yoghurt

“…The syneresis was reduced at longer time and amplitude of ultrasound (Delgado et al . 2020) because sonication increased collision probability between proteins and fats and rearranged networks by forming new interactions (Jambrak et al . 2008).…”

“…Similar results have been reported by Delgado et al . (2020), where the cohesiveness of yoghurt generally decreased with an increase in goat milk sonication (Delgado et al . 2020).…”

“…(2020), where the cohesiveness of yoghurt generally decreased with an increase in goat milk sonication (Delgado et al . 2020). Gumminess is calculated by multiplying the hardness and cohesiveness values of samples.…”

Application of multi-frequency power ultrasound in selected food processing using large-scale reactors: A review

“… [123] Ultrasound (20 kHz) Effect of ultrasound on probiotic goat milk yogurt Sonication for 6 min enhanced the apparent viscosity and consistency, reducing tyramine and total biogenic amine. [124] Ultrasound-assisted matrix solid-phase dispersion pesticide extraction from fruits and vegetables An efficient, simple, cheap, robust, and environmentally friendly ultrasound-assisted method was developed for extracting different pesticides. [125] Ultrasound combined with carbon Effect of ultrasound with carbon dots coating on the microbial and physicochemical quality of fresh-cut cucumber.…”

Recent Insights Into Processing Approaches and Potential Health Benefits of Goat Milk and Its Products: A Review

“…As a result, ultrasonic technology might be used in the dairy industry to improve the quality of rennet coagulation during the manufacturing of goat milk cheese ( 83 ). In addition, after being exposed to ultrasound for 6 min, the apparent viscosity and consistency index of several yogurt samples obtained from goat milk was considerably improved ( 84 ).…”