Antioxidant Activity, Fiber, Acidity (pH), and Population of Lactic Acid Bacteria in Green Juice as Functional Beverages

Ni Wayan Nursini,Komang Lina Venti,I Gusti Ayu Wita

doi:10.29037/digitalpress.22331

Abstract

Bok choy (Brassica rapa L) is a vegetable group of Brassicaceae which still a family with Chinese vegetables. It contains phytochemical substances such as carotenoids, β-carotene, and glucosinolates which are a source of antioxidant. Bok choy can be processed into juice. The purpose of this research is to determine the content of the antioxidant activity, fiber, acidity (pH) and population of lactic acid bacteria in each formulation. The other ingredients added in making this green juice are yogurt and honey made into 5 formulations. The analysis of this research was the analysis of antioxidant activity content using DPPH method (2.2, -diphenyl-1- picrylhydrazyl), crude fiber contents analysis using gravimetric method, pH analysis using pH meter and analysis of lactic acid bacteria using spread plate method. The result obtained is the highest content of the antioxidant activity was found in formulation 5 consist of 30 g yogurt, 15 g honey and 50 g bok choy with 35,198 ± 0,057%. The content of crude fiber ranged from (0,447 ± 0,046) g to (0,507 ± 0,058) g. The highest of acidity (pH) is in formulation 1 which consists of 10 g of yogurt, 15 g of honey and 50 g of bok choy at 5,50 ± 0,040. The highest population content of lactic acid bacteria in formulation 5 consists of 30 g yogurt, 15 g honey and 50 g bok choy at 2,8 x 106cfu/mL. Therefore, green juice can be used as functional drinks.

Highlights

In Indonesia, consumption of vegetables and fruit and its processing is still low
The juice that has been blended based on a predetermined formulation as described in Table 1 was analyzed for its antioxidant activity, crude fiber content, acidity and lactic acid bacteria (LAB) population
The results of this study showed the antioxidant activity of green juice ranged from 22.395 ± 0.051% to 35.198 ± 0.057%

Summary

Introduction

In Indonesia, consumption of vegetables and fruit and its processing is still low. Consumption of fruits and vegetables that do not meet the recommendation gives effects on the supply of vitamins, minerals, and fiber needed by the body [1]. Bok choy vegetable is one of the vegetables that can be made in the form of juice as a functional drink. Probiotics in inhibiting pathogenic organisms by competing to obtain a number of food ingredients for fermentation. These foods are needed so that probiotics can develop properly. That research was conducted to find out how the antioxidant activity, fiber, acidity (pH) and lactic acid bacteria (LAB) population in green juice formulations as functional drinks

Preparation of Green Juice Samples

Antioxidant Activity of Green Juice Samples

Crude Fiber of Green Juice Samples

Total Lactic Acid Bacteria of Green Juice Samples

Fiber Crud of Green Juice Samples

Conclusions