Estimation of betacyanin and betaxanthin content in blended beverage of Bottlegourd, beetroot and Aloevera

Introduction

Fruits and vegetables tend to have very limited shelf life due to its perishable nature. In order to preserve, they are processed to Ready to Serve (RTS) beverages. RTS beverage is a nonfermented beverage prepared from fruits and vegetables of different concentrations with addition of sugar, water and additives (Rathinasamy et al. 2021) [ 8] . The bottle gourd, also called the white-flowered gourd (Lagenaria siceraria (Mol) Standl.), is a member of the Cucurbitaceae family. Bottle gourd or Lauki juice is an excellent remedy for the excessive thirst caused by diabetes, diarrhoea and over consumption of fatty foods (Bhattacharya and Das, 2012) [1] . The brilliant crimson beetroot (Beta vulgaris L.), sometimes referred to as chard, spinach beet, sea beet, garden beet, white beet and chukander (in Hindi), is a member of the Chenopodiaceae family. It is well-known for both its therapeutic qualities and highly prized juice. Geosmin is the reason why fresh beetroot juice has a muddy flavor. It comes in a variety of forms, with the bulb hues varying from yellow to red. The most widely consumed beetroots for human consumption are those with a deep red color, either cooked or raw for salad or juice. Betalain present in beetroot serve as an osmolyte (protecting cells against dehydration), an antioxidant (protecting cells against free radicals), a methyl group donor (lowering potentially harmful levels of homocysteine) and a vascular protectant which effect human health and function (Bloomer et al., 2011) [2] . Aloevera gel is used in the food business, processing the plant's leaf pulp has grown to be a significant global industry. It has been used as a source for functional food, particularly in the production of Aloevera gel-based health drinks (Ramachandra and Srinivasa Rao, 2008) [7] . Vegetables are a major source of essential vitamins and minerals, such as vitamin A, vitamin C and potassium, needed for human wellbeing. They are, however, perishable living products that require coordinated activity by growers, storage operators, processors and retailers to maintain quality and reduce food loss and waste (Lipinski et al. 2013) [6] . Fruit beverages such as ready-to-serve (RTS) are becoming more and more popular in comparison to synthetic drinks, evidently because of their taste, flavor and nutritional value (Gaikwad et al., 2013) [4] . More than 20-25 per cent of fruits and vegetables in India perish before they are used. Even though India is the second-largest producer of fruits and vegetables in the world, just 1.5 per cent is processed. The advantage of RTS beverage is that there is no need to dilute it whereas squash, syrup, cordial, crush are diluted with water before use. Ready-to-serve beverages are made out of juice, sugar, water and consumed as such. Recently due to health consciousness among people there is shift of preference towards the consumption of vegetables and vegetables based products including beverages. Natural beverages could be substituted for those synthetic preparations, it would be desirable to the consumers as well as to the manufacturers.

Material and Methods

Extraction of juice from Bottle gourd, beetroot and Aloevera

Fresh and tender bottle gourd fruits were selected for the experiment. The fruits were then peeled, top 20 mm and bottom 15 mm of bottle gourd was cut and removed. The fruits were sliced (around 5mm thickness) using a stainlesssteel knife and were immediately blanched at 80 °C for 3-4 min in order to deactivate enzymes and avoid browning. After blanching fruit pieces were used to extract juice by using a mechanical juice extractor. The peeled beetroots were cut into small slices and blanched. Blanching inactivates the enzymes and retains the colour of beetroots. The water blanching method described by Karla, 1990 was adopted. The cubes to be blanched were loosely tied in a muslin cloth and were dipped in hot water at 80 °C for 3-5 minutes. Immediately after blanching the cubes in muslin cloth were held under running tap water to prevent further cooking. The blanched beetroot was passed through mixer. Obtained pulp was passed through muslin cloth to get clear beetroot juice. The Aloevera pulp was taken out by the traditional hand filleting method to avoid the contamination of internal fillet with the yellows sap. The fresh, succulent, undamaged, mature (3-4 years), rot free leaves were selected for preparing the juice. The lower 1 inch of the leaf base, the tapering point of 2-4 inches of leaf top and the short, sharp spines along the leaf margins were removed by using a sharp knife. The pulp was then heated at 60-65 °C for 10 minutes and grinded in mixer-grinder. The mashed pulp was then strained using clean muslin cloth to get pure Aloevera juice.

Preparation of RTS

After obtaining pure Bottle gourd, Beetroot and Aloevera juice the RTS was prepared by blending all three juices in different concentrations as per the treatments and homogenization was done for all the treatments of RTS. After that, the prepared strained syrup solution (sugar + water + acid) was added into the mixture of juice and processed upto 85-90 °C for 20 minutes and filled into the pre-sterilized colourless glass bottles of 200 ml capacity and sealed air tight using crown caps with the help of a crown corking machine. The products were pasteurized in boiling water (90 °C) for 30 min. The recipe for preparation of RTS was sugar, according to TSS (10%), water 900 ml, citric acid @ 3gm/lt of RTS and sodium benzoate @ 0.1g/lt of RTS were added as a preservative.

Determination of Betacyanin and Betaxanthin content

The betalain content (Betacyanin and Betaxanthin) was quantified by a method described by Mobhamed et al. ( 2013). The beetroot juice was diluted (30 times) with distilled water and the absorbance of the diluted juice was read at 538 nm and 480 nm using a spectrophotometer. The betalain content were determined spectrophotometrically (UV visible single beam spectrophotometer) using an equation proposed by Cai and Corke (2000) [3] .

The Betacyanin content was calculated as

Wherein, A is the absorption value at betanin λ max (538 nm) DF is a dilution factor, MW is the betanin molecular weight (550 g mol-l), ε is the betanin molar extinction coefficient (60,000 L mol-l cm-1) and L is the path length (1.0 cm) of the cuvette.

Betaxanthin content was calculated as

Wherein, A is the absorption value at indicaxanthin λ max (480 nm) DF is a dilution factor, MW is the indicaxanthin molecular weight (308 g mol-l), ε is the indicaxanthin molar extinction coefficient (48,000 L mol-l cm-1) and L is the path length (1.0 cm) of the cuvette decreased from 6.05 mg/100 gm at 0 days to 3.94 mg/100 gm at 90 days of storage period. and Betaxanthin content in T 6 decreased from 2.44 mg/100 gm at 0 days to 1.17 mg/100 gm at 90 days of storage period. The Significant reduction in betalain (betacyanin and betaxanthin) content of RTS was observed during storage. This decrease in betalain content might be due to their high susceptibility to auto-oxidative degradation and poor stability during storage.

References

1. Bhattacharya S, Das B. Antidiabetic activity of Lagenaria siceraria pulp and seed extract in normal and alloxan-induced diabetic rats. International Journal of Pharmaceutical Sciences and Research. 2012;3(9):3362-3369.
2. Bloomer RJ, Famey TM, Trepanowski JF, McCarthy CG, Canale RE. Nitrate/nitrite in exercise-trained men. Journal of the International Society of Sports Nutrition. 2011;8(5):1-7.
3. Cai YZ, Corke H. Production and properties of spraydried amaranthus betacyanin pigments. Journal of Food Science. 2000;65(6):1248-12452.
4. Gaikwad K, Suman S, Shakya BR. Studies on the development and shelf life of low-calorie herbal aonlaginger RTS beverage using artificial sweeteners. Journal of Food Process Technology. 2013;4(200):1-4.
5. Karla CL. Effects of blanching in vegetable processing. Indian Food Packer. 1990;44(5):3-16.
6. Ramachandra C, Rao PS. Processing of Aloe Vera Gel: A review. American Journal of Agricultural and Biological Sciences. 2008;3(2):502-510.
7. Rathinasamy M, Ayyasamy S, Velusamy S, Suresh A. Natural fruits-based ready-to-serve (RTS) beverages. Journal of Food Science and Technology. 2021;59(4):17.