Impact of sea buckthorn seed oil microcapsules on the overrun, thickness and firmness of the ice cream
The specifications of the ice cream that we made are presented in Table 1. The overrun of the ice cream varied from 77%, with the SBSOM ice cream showing a slightly higher overrun (76.55±0.02%) compared to the control (69.06±0.02%) and SBSO ice cream (75.03±0.02%). The viscosity of the ice cream varied between 45% and 85%. SBSOM ice cream had a superior viscosity in comparison to the control, but the viscosity difference between SBSOM and SBSO ice creams was minimal (84.18±0.02 cP). The hardness of the ice cream samples varied from 41.70 to 52.63 grams. SBSOM ice cream was the softest (41.70± 0.02 g), followed by SBSO ice cream (44.52±0.02 g), while the control ice cream had the highest hardness (52.63± 0.02 g). Overrun indicates the volume of air assimilated into ice cream, which creates bubbles that need to be generated and stabilized. This factor is crucial in determining the texture and sensory qualities of the ice cream (
Kurt and Atalar, 2018). When sea buckthorn seed oil (SBSO) and encapsulated sea buckthorn seed oil (SBSOM) were added, they both enhanced the overrun of the ice cream. The overrun of SBSOM ice cream (T2, T3) was slightly higher than that of SBSO ice cream (T4, T5), which aligns with findings by
(Velotto et al., 2021). This increase in overrun suggests that the ice cream mixture became more stable. However, the overrun of all samples was still lower than the 129-144% range seen by
(Borrin et al., 2018), who added curcumin-nano emulsion to their ice cream. The higher overrun in SBSO ice cream might be due to the larger amount of fat, which increases the apparent viscosity of the ice cream mix and allows for more air to be incorporated during freezing
(Makouie et al., 2021). The viscosity of SBSOM ice cream (T2 and T3) was marginally elevated than SBSO ice cream (T4 and T5), as shown in Table 1. This difference is because carbohydrates (such as maltodextrin and sodium caseinate) were used to encapsulate the SBSO and carbohydrates are known to increase viscosity in foods
(Lima et al., 2016). Higher viscosity helps break down air cells more efficiently. Consequently, SBSOM ice cream exhibited enhanced thickness in comparison with the control sample. Hardness in ice cream is influenced by several factors, including viscosity, solid content and air
(Yan et al., 2021). Overrun, defined as the capacity of the ice cream matrix to retain air bubbles, was evaluated by measuring the percentage increase in volume resulting from the incorporation of air during the whipping of the ice cream mix throughout the freezing process (
Muse and Hartel, 2004). Air bubbles are formed during the production process as a result of stirring the ice cream mixture (
Sung and Goff, 2010).The air bubbles in ice cream distribution result in smooth texture and affect the physical properties of melting and hardness of ice cream (
Sofjan and Hartel, 2004).Overrun and hardness are inversely related; as overrun raises, the ice cream becomes softer. For example,
(Kulkarni et al., 2017) found that adding pumpkin powder to ice cream increased viscosity, which in turn reduced the ice cream’s hardness.
Enumeration of phenolic and antioxidant attributes of ice cream
Table 2 presents the total phenolic content and antioxidant properties of SBSOM and SBSO ice cream. The TPC for SBSOM ice cream was measured as (21.82±0.02 μg GAE/ml) for T2 and (23.11±0.02 μg GAE/ml) for T3, while SBSO ice cream had values of (22.52±0.01 μg GAE/ml) for T4 and (24.52±0.02 μg GAE/ml) for T5. In terms of antioxidant activity, the DPPH inhibition percentage for SBSOM ice cream was (86.24 ± 0.02%) for T2 and (87.39±0.02%) for T3, while for SBSO ice cream, it was (87.25±0.02%) for T4 and (88.73±0.02%) for T5. The DPPH scavenging activity in the ice cream with SBSO was in line with the findings from (
Mishra et al., 2020). SBSO ice cream showed enhanced antioxidant and phenolic levels in contrast to the ice cream made accompanied by encapsulated SBSO. This could be due to the elevated temperatures used in the spray drying process for making SBSO powder, as temperatures above 60
oC can reduce the activity of bioactive compounds in the oil. These results are similar to those of (
Nguyen and Hwang, 2016), who found that increasing the amount of Aronia juice led to higher polyphenol and flavonoid content compared to a control group. Antioxidants are molecules that prevent or slow the oxidation of other substances by inhibiting the initiation or propagation of oxidative chain reactions (
Halliwell, B. and Gutteridge, J. M., 2015). The antioxidant effect encompasses the enhancement of antioxidant enzyme activity and the suppression of oxidase activity. Free radicals can be generated through redox reactions and the peroxidation of transition metal ions, such as iron and copper. Consequently, promoting the synthesis of antioxidant enzymes, alongside reducing the activity of oxidases and the formation of metal ions, can effectively exert a strong antioxidant effect
(Ji et al., 2020). In this study, the TPC of the ice cream increased with SBSOM (T2 and T3) contrasted with SBSO (T4 and T5). The less phenolic content found in SBSO ice cream could be due to the deprivation of volatile compounds during the production procedure. The results regarding the TPC of SBSOM ice cream are consistent with the findings by
(Deme et al., 2021). The antioxidant potential of plant-based foods is primarily influenced by their polyphenolic content. Phenolic compounds are the predominant bioactive constituents responsible for the antioxidant activity observed in plants. This activity is largely attributed to their redox properties, which facilitate the scavenging of free radicals and the neutralization or decomposition of peroxides
(Ursache et al., 2017). Higher phenolic content in foods can help prevent diseases caused by oxidative stress
(Durmaz et al., 2020).
Sensory evaluation
Table 3 presents the sensory evaluations for different characteristics, including body and texture, color and appearance, mouthfeel, flavor and overall preference, of the five ice cream samples. Small differences in sensory properties were observed between the control and SBSOM ice cream. For color and appearance, SBSOM ice cream scored (7.94±0.02) for T2 and (7.82±0.02) for T3, while SBSO ice cream scored (7.72±0.02) for T4 and (7.32±0.02) for T5. Treatments T1 and T3 exhibited superior body and texture in comparison to treatment T2, likely due to the added viscosity from the microcapsules. The flavor scores for the control and SBSOM ice creams (T2) were (8.12± 0.02) and (8.12±0.02), respectively, while SBSO ice cream (T5) had a lower flavor score of (5.12±0.02). The incorporation of microcapsules has led to a marked intensification in the flavor profile, particularly when compared to non-encapsulated counterparts. This enhancement is likely associated with the prominent aftertaste of sea buckthorn seed oil, which is characterized by a pronounced fresh note. For mouthfeel, both the control and SBSOM ice creams (T2) scored (7.52±0.02). In contrast, SBSO ice cream (T4 and T5) had a mildly sour aftertaste, with normal ratings of (5.72±0.02) and (5.02±0.02), respectively. In terms of overall acceptability, treatments T1 and T2 received the highest scores of (7.72 ±0.02), which were higher than the other treatments. There was a small difference in color and appearance between SBSOM and SBSO ice creams. SBSO ice cream had a creamy-yellowish color and adding SBSOM didn’t affect the ice cream’s visual appearance. This finding is similar to the study by (
Mishra et al., 2020), which noted that yogurt with encapsulated seed extract had a higher color score compared to yogurt with just seed extract.SBSO ice cream also had a flavor profile similar to that of oil-enriched ice cream described by (
Ramadan, 2012), which had a flavor score of (6.56±0.88). The texture and body of SBSO ice cream (T4 and T5) were rated higher than SBSOM ice cream (T2 and T3), likely due to the increased viscosity from adding microcapsules.
(Agrawal et al., 2016) observed only minor differences in texture and body when ginger juice was added to ice cream. In the case of basil oil ice cream, a bitter aftertaste was noted. The overall acceptance scores in this study align with the findings of
(Zanjani et al., 2018), which showed no off-flavors after adding encapsulated probiotic strains.These findings indicate that encapsulation aids in minimizing the adverse effects (such as undesirable tastes, color and texture) of SBSO in food items.