Application of ultrasound to extend the shelf life of shalgam juice: Changes in various physicochemical, nutritional, and microbiological properties

Abstract

Shalgam juice is a traditional lactic acid fermented beverage, which has intense red color and sourish taste. This study aimed to determine various physicochemical and microbiological changes in shalgam juice after ultrasound application to extend the shelf life of the juice. Ultrasound was applied to the samples at different amplitudes, temperatures, and times in combination. Analyses were performed on the samples at five different stages throughout the storage. The lactic acid amount, lactic acid bacteria count, color values, except a*, were higher in the samples that were treated with ultrasound, whereas the amounts of ethyl alcohol, acetic acid, propionic acid, and the pH values were lower compared to the control at the end of the storage. Ultrasound application had no significant changes in anthocyanins, antioxidant activity, and color of the samples. It can be said that ultrasound application to shalgam juice can be an alternative method to improve its shelf life. Novelty impact statement Shelf life of shalgam juice is limited to 3 months and it can be extended to 1–2 years by adding preservatives or pasteurization. However, pasteurization has negative effects on the sensory properties of the product and chemical preservatives are being replaced by alternative methods in recent years due to consumer sensitivity. In this study, ultrasound was applied to shalgam juice to extend the shelf life of the product.

Pulsed electric field for shalgam juice: effects on fermentation, shelf‐life, and sensory quality

“…1(C)). Admittedly, our b* values were lower than that of some shalgam juice studies 44,45 . However, the b* values determined in the study of Tanguler et al ., 34 who used similar production methods to this study, were compatible with our outcome.…”

“…Admittedly, our b* values were lower than that of some shalgam juice studies. 44,45 However, the b* values determined in the study of Tanguler et al, 34 who used similar production methods to this study, were compatible with our outcome. Therefore, the differences detected in the b* values were probably due to differences in production methods.…”

“…In other words, PEF treatment caused an increase in the number of yeasts both after fermentation and throughout storage. Similarly, Ulucan et al 45 determined that the number of yeasts increased in the ultrasound-treated shalgam juice samples. This may be due to the stress response of yeast cells to PEF or ultrasound conditions.…”

“…Ates et al 50 also reported that the content of anthocyanins and dominant phenolic acids, caffeic acid and vanillic acid, in shalgam juice decreased at the end of the 60th day. On the contrary, Ulucan et al 45 observed no changes in TPC values of shalgam juice treated with ultrasound during 6 months of storage.…”

Effects on quality characteristics of ultrasound-treated gilaburu juice using RSM and ANFIS modeling with machine learning algorithm

“…4 ). Ulucan et al (2022) documented a notable rise in TAC and shelf life following 50 °C and 15-minute ultrasound treatment of turnip juice [49] . Bayati et al (2021) showed a 5.45 % decrease in TAC in their ultrasound treatment of pomegranate juice compared to the control [50] .…”