Effect of different pasteurisation temperature on physicochemical properties, bioactive compounds, antioxidant activity and microbiological qualities of reconstituted pomegranate juice (RPJ)

Abstract

Reconstituted pomegranate juice (RPJ) was thermally treated with high-temperature pasteurisation (HTP) at 95°C and mild-temperature pasteurisation (MTP) at 80°C for 30 s respectively. As a comparison, the effect on physicochemical properties, including antioxidant activities and microbial inactivation was eavluated. Both MTP and HTP showed effective inactivation of microbial growth to negligible level with MTP taking almost half pasteurisation-time (-46.3%) as compared to HTP, indicating possible less energy usage. MTP and HTP treatment delivered insignificant difference in pH, titratable acidity, total soluble solids and colour changes (ΔE) based on Commission Internationale de l’Elcairage (CIE) colour system. A significantly higher CIE a values and reduction in L and b were obtained for MTP-juice indicating an increase in red tonalities due to increase in anthocyanin contents. As for antioxidant activity and extractability of bioactive compound, interestingly HTP delivered better results due to more phenols and anthocyanin were released during the heating, leading to further release of initially membrane‐bound phenols. These findings suggested that both HTP and MTP are able to meet the microbiological safety and comparable physicochemical qualities. Nonetheless, HTP has shown higher functional values due to higher extractability of antioxidant compounds.

Physicochemical Properties, Bioactive Compounds Degradation Kinetics, and Microbiological Counts of Fortified Pomegranate Gummy Candy (GC) during Ambient Storage

“…The mixture was heated to 95 °C for 30 seconds and subsequently cooled to 40 °C. The high temperature was used for heating since this enabled the release of membrane-bound phenolic content in the juice following the study by Kong et al (2020). Finally, vitamin C was fortified by adding vitamin C into the cooled mixture, reducing the pH from 4.11 to 3.20. pH below four was found to help slow down microbial growth, as evidenced by the study conducted by Kong et al (2020).…”

“…The high temperature was used for heating since this enabled the release of membrane-bound phenolic content in the juice following the study by Kong et al (2020). Finally, vitamin C was fortified by adding vitamin C into the cooled mixture, reducing the pH from 4.11 to 3.20. pH below four was found to help slow down microbial growth, as evidenced by the study conducted by Kong et al (2020). The mixture was then poured into molds, and as it cooled further, it began to set and take the shape of the molds.…”

“…Due to the chewy texture, GC was well-liked by children under seventeen (Periche et al, 2014). Recently, the use of pomegranate fruits as an ingredient for food products has gained interest because of its substantial antioxidant properties sourced from its phenolic compounds, including for confectionery production (Alyas et al, 2020;Kong et al, 2020). Besides having high antioxidant activity, pomegranate has a significant pectin content, making it an ideal ingredient for producing confectionery products such as GC and jellies (Garrido et al, 2015).…”

“…Nevertheless, there was limited understanding regarding the impact of using pomegranate juice as a source of phenol enrichment, coupled with vitamin C fortification, on gummies' key physicochemical and textural attributes. Conversely, studies on various food products revealed that the stability of vitamin C and phenolic compounds could be compromised during storage, which was not ideal for consumers seeking optimal bioactive compound content (Basha et al, 2020;Kong et al, 2020). Therefore, assessing these specially formulated gummies holds significant importance, as it may serve as a reference point for manufacturing gummies with desirable qualities and functional value derived from vitamin C and phenols, which act as antioxidants for potential health benefits.…”

Effect of pasteurization time and temperature on bioactive compounds, antioxidant ability and color value of beverage produced from herbal extract (Passiflora foetida and embryo nelumbinis)

“…At pasteurization temperature and time were 85 o C and 30 minutes, the color parameters of product had suitable values that the making to product was good color. According to Kong et al [32], the pasteurization changed color parameters of pomegranate juice, it increased a * value, decreased b * and L * values while E values did not change significantly. In addition, a study of Buniowska et al [33] showed that there were an increasing of L * and b * values, and decreasing of a * value after heating fruit beverages.…”