Antioxidant Properties of Fruit and Vegetable Whey Beverages and Mousses -

Antioxidant Properties of Fruit and Vegetable Whey Beverages and Mousses

The study assesses the antioxidant activity, total phenolic content, total flavonoids content and lipophilic pigments (β-carotene, chlorophyll a, chlorophyll b) content in homemade, marketed fruit and vegetable whey beverages and fruit and vegetable mousses. The highest polyphenol content was found in the homemade green whey beverage W1G (541.95 mg/100 g) and the lowest in the market green whey beverage W2G (46.18 mg/100 g). In the fruit and vegetable mousses under study, the highest content of polyphenol compounds was determined in the red mousse R3 (76.41 mg/100 g). The highest content of flavonoids was observed in the homemade orange whey beverage W1O (63.06 mg/100 g) and in the green mousse G2 (69.80 mg/100 g). The highest content of β-carotene was identified in homemade orange whey beverage (4.36 mg/100 g) and in orange mousses (in range 1.10–2.24 mg/100 g), while chlorophylls a and b in homemade green whey beverage W1G (3.00 mg/100 g and 1.31 mg/100 g respectively) and in green mousses (chlorophyll a in range 0.54 to 1.42 mg/100 g and chlorophyll b in range 0.13 to 0.32 mg/100 g).

Materials and Methods

The acid whey was obtained during the traditional production of semi-skimmed curd from cow’s milk pasteurized at 83 ^◦C for 15 min. Whey was used to make homemade fruit and vegetable whey beverages. Three variants of this type of beverages were obtained, containing approx. 50% of acid whey and 50% of other ingredients (carrot puree, roseship puree, sea buckthorn jam in orange beverage; pear puree and concentrated cherry juice in red beverage; parsley and banana puree in green beverage). The beverages were obtained by thoroughly mixing the whey with the remaining components using blender. The analysis also covered market whey beverages from Piątnica and fruit and vegetable mousses of the following brands: Bobovita, Bobofrut, Gerber, Hortex, Dawtona, Freche Freunde. The abbreviations used in the experiment are: W1O, W1R and W1G for homemade fruit and vegetable whey beverages; W2O, W2R and W2G for the market fruit and vegetable whey beverages; O1, O2, O3; R1, R2, R3; G1, G2, G3 for orange, red and green fruit and vegetable mousses, respectively. For the analysis, 5 g of the research materials was diluted five times with distilled water and then centrifuged in an Eppendorf type centrifuge (4000 rpm/10 min). Prepared extracts were used to determine the antioxidant activity by DPPH and ORAC tests and total phenolic contents (TPC) and total flavonoid content (TFC). For the determination of lipophilic pigments (β-carotene and chlorophylls) the acetone-hexane extracts were prepared.

The determination of the antioxidant activity by the DPPH and ORAC method was carried out. Total Phenolic Content (TPC) was determined by Folin-Ciocalteu reagent method. Determination of Total Flavonoid Content (TFC) by standard method with catechin was a standard. Determine the content of lipophilic pigments, including carotenoids with a reagent acetone and hexane (1:1, v/v).

Results:

The polyphenol content in the homemade whey beverages was respectively over eight times, three and a half times and twelve times higher than in the market whey beverages in these colors. The content of phenolic compounds did not differ significantly in the case of the market orange (W2O) and green (W2G) whey beverage. The highest content of flavonoids was observed in the homemade orange whey beverage (W1O). It was more than one and a half times higher than in the homemade red (W1R) and green (W1G) whey beverages and about four and a half times higher than in the market whey beverages (W2O, W2R, W2G). The content of flavonoids did not differ significantly in the homemade red (W1R) and green (W1G) whey beverages and the market orange (W2O), red (W2R) and green (W2G) whey beverages. The lowest content of flavonoids was identified in market orange (W2O) and red (W2R) whey beverages.

Antioxidant activity (DPPH, ORAC) were used to determine the antioxidant activity in the analyzed homemade and market fruit and vegetable whey beverages. The antioxidant activity measured by the DPPH test was at the highest level in the homemade green whey beverage (W1G). This activity did not differ significantly from that of the homemade orange (W1O) and red (W1R) whey beverages. The antioxidant activity of the homemade whey beverages was seven, eleven and six times lower in the market orange, red and green whey beverages. Market red whey beverage (W2R) had the lowest antioxidant activity. The antioxidant activity measured by the ORAC test was the highest in homemade red whey beverage (W1R). Homemade orange, red and green whey beverages had respectively 39%, 38% and 13% higher levels of antioxidant activity than market whey beverages in these colors. The results of the antioxidant activity in the homemade orange, red and green whey beverages measured with the DPPH test were higher than in the ORAC test by 10%, 6% and 12%, respectively. The opposite tendency was observed in the case of market whey beverages higher values of antioxidant activity were determined in the ORAC test.

Among the lipophilic pigments found in the analyzed homemade and marketed fruit and vegetable whey beverages, compounds belonging to the group of carotenoids (β-carotene) and chlorophylls (chlorophyll a and chlorophyll b). The highest content of β-carotene was determined in the homemade orange whey beverage (W1O). Its content was over five, twenty and two hundred and eighteen times lower in the homemade green whey beverage (W1G) and market orange (W2O) and green (W2G) whey beverages. The higher level of chlorophyll a was in the homemade green whey beverage (W1G). The homemade and market red whey beverages contained over 33 times lower amounts of this compound, and the homemade orange whey beverage and market green and orange whey beverages contained 150, 150 and 300 times less, respectively. A similar tendency was observed in the content of chlorophyll b the highest content was observed in the homemade green whey beverage. The content of chlorophyll b was ten times lower in the homemade and market whey beverages and several dozen times lower in the market green, homemade orange and market orange whey beverages compared to the homemade green whey beverage.

In the fruit and vegetable mousses under study, the highest content of polyphenolic compounds was determined in the red mousse R3. It was by 44%, 36% and 36% higher than in orange mousses O1, O2 and O3; 34% and 7% higher than in red mousses R1 and R2 and 26%, 9% and 19% higher than in green mousses G1, G2 and G3. The lowest content of phenolic compounds was found in orange mousse O1. Similar values of phenolic compounds were observed in orange mousses O1, O2 and O3, red R1 and green G1. The content of flavonoids was at the highest level in the green mousse G2. The amount of flavonoids in green mousse G2 was 27%, 52% and 9% higher than in orange mousses O1, O2 and O3; 62%, 29 and 85% higher than in red mousses R1, R2 and R3.

Antioxidant Activity Two tests (DPPH, ORAC) were used to determine the antioxidant activity in the analyzed fruit and vegetable mousses. The significantly highest antioxidant activity measured with the DPPH test was determined in the red mousse R2. It was by 39%, 55% and 112% higher than in orange mousses O1, O2 and O3; 59% and 8% higher than in red mousses R1 and R3 and by 118%, 17% and 128% higher than in green mousses G1, G2 and G3. There were no statistical differences in the amount of antioxidant activity in red R3 and green G2 and in orange O1, O2 and red R1 mousses. Green mousse G3 had the lowest antioxidant activity. The value of its antioxidant activity was similar to the activity value of orange mousse O3 and green mousse G1. O3 orange mousse was characterized by the highest antioxidant activity as measured by the ORAC test. This activity was higher by over 20% than in the orange mousses O1 and O2; 16%, 77% and 21% higher than in R1, R2 and R3 red mousses and 36%, 24% and 164% higher than in G1, G2 and G3 green mousses.

The content of individual lipophilic pigments in the analyzed fruit and vegetable mousses varied depending on the raw material composition. The orange mousses contained the most β-carotene. O2 mousse was determined with the highest amounts of β-carotene—about twice as much as O1 and O3 mousses. Among green mousses, the greatest amount of β-carotene was found in G1 mousse, which contained almost twice as much of this compound as G3 mousse and over 3 times more than G2 mousse. Red mousses were the most deficient in β-carotene. The β-carotene content in the R1 and R2 mousse was 28 times lower than in the O2 mousse.

The highest levels of chlorophyll a were accumulated by green mousses (0.54–1.42 mg/100 g). Chlorophyll b content was also dominant in green mousses (0.13–0.32 mg/100 g). The relatively high content of chlorophyll b was found in O2 mousse (0.11 ± 0.06 mg/100 g) and R1 (0.10 ± 0.01 mg/100 g). The lowest level of chlorophyll b was identified in the mousse O1, O3 and R2.

Conclusions

The antioxidant activity and the content of selected antioxidants in analyzed fruit and vegetable products (whey beverages, mousses) were determined by the composition and percentage share of individual plant raw materials. Homemade whey beverages, due to the higher addition of fruit and vegetable components (up to 50%), were characterized by significantly higher antioxidant activity and content of phenolic compounds, flavonoids and lipophilic pigments. The addition of whey in fruit and vegetable beverages highly contributes to the enhancing of their nutritional value. Whey is a rich source of minerals, among others calcium, phosphorus, sodium and potassium. Taking into account the results of the obtained research, it is worth using a higher addition of fruit and vegetable components in dairy products available on the market. It is a valuable indication for food producers to enrich dairy products with higher amounts of fruit and vegetable components to increase their health-promoting properties. Enrichment of dairy products with antioxidant compounds, including polyphenols, carotenoids and chlorophylls, significantly increases their antioxidant potential and improves taste.

Reference:

Purkiewicz, A. and Pietrzak-Fiećko, R., 2021. Antioxidant properties of fruit and vegetable whey beverages and fruit and vegetable mousses. Molecules, 26(11), p.3126.