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Modulating Yogurt Fermentation Through Pulsed Electric Fields and Influence of Milk Fat Content
Graciela A Miranda-Mejía1, Anaberta Cardador-Martínez2, Viridiana Tejada-Ortigoza1
1Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Ave. Eugenio Garza Sada 2501, Monterrey 64849, NL, Mexico.
Foods (Basel, Switzerland)
|June 13, 2025
Summary
Pulsed electric fields (PEFs) can speed up yogurt fermentation by stimulating lactic acid bacteria. This technology enhances nutrient uptake and acidification, reducing fermentation time without affecting final product quality.
Area of Science:
- Food Science and Technology
- Microbiology
- Biotechnology
Background:
- Yogurt production relies on lactic acid bacteria for fermentation, impacting nutritional and probiotic qualities.
- Optimizing yogurt fermentation time is crucial for efficient processing and maintaining product quality.
- Pulsed electric fields (PEFs) show potential for stimulating microbial activity in food processing.
Purpose of the Study:
- To investigate the effect of low-intensity PEF treatments on yogurt starter cultures in milk.
- To evaluate the impact of PEF-treated inoculum on fermentation kinetics and key quality parameters of yogurt.
- To determine the optimal PEF parameters for enhancing yogurt fermentation efficiency.
Main Methods:
- Yogurt starter inoculum suspended in milk (IM) with varying fat content (0.5-2.8%) was treated with PEFs (1 kV/cm, 800-1600 µs).
- Fermentation kinetics were monitored by measuring pH, soluble solids, lactose, lactic acid, and riboflavin concentrations over 6 hours.
- PEF-treated IM (PEF-IM) was compared against untreated IM (C-IM) in inoculated milk.
Main Results:
- PEF treatments reduced fermentation time by 4.3-20.4 minutes compared to controls.
- The shortest fermentation time (5.1 h) was achieved with PEF-IM (2.8% fat) treated at 1 kV/cm for 1600 µs.
- PEF-IM enhanced lactose consumption (1.6-3.1%) and increased lactic acid production (7.2%) compared to C-IM.
Conclusions:
- PEFs promote reversible electroporation in microbial cells, enhancing nutrient uptake and acidification.
- PEF treatment of yogurt inoculum is a promising assisted-fermentation approach for improving yogurt production efficiency.
- This technology offers a method to reduce fermentation time without compromising yogurt quality.
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