Extraction and process optimization of East Indian Red Wood (Caesalpinia sappan) in stirred yoghurt

Abstract

Yoghurt is a fermented dairy product, having several health benefits. Redwood sappan wood (Caesalpinia sappan) is a plant yielding bark and stem with water soluble red pigment. Two methods of colour extraction were carried out, namely, Heat Extraction (extraction by aqueous & alcohol) and Cold Extraction (Ambient temperature & Refrigerated temperature) using five different medium such as distilled water, potable water, sodium carbonate solution, sodium hydroxide solution and ethyl alcohol. Among the mediums tried, potable water was found to be the best medium for extraction. The bark was heated in potable water for 2.5 h. The heat extracts had a pleasing pink to red colour. The colour of the extract was pH dependent, it was yellowish to brown at below neutral and pink to dark red at above neutral pH. Stirred type of yoghurt was prepared by standard method using cow milk. Redwood extract level was optimized at three levels viz. 10 mL, 20 mL and 30 mL with skim milk powder @ 40 gm and sugar 20 gm per 100 mL of yoghurt. Redwood extract 20 mL optimized based on 9-point Hedonic scale, textural parameter and storage stability of colour extraction up to 7 days. Physico-chemical analysis of the redwood added stirred yoghurt product such as pH, acidity(%), Lactose (%),Sucrose (%), Protein (%), Ash (%), Fat (%) values are 4.6±0.01, 1.02±0.00, 5.76±0.01, 20.44±0.02, 3.89±0.01, 1.10±0.01 and 2.49±0.10. respectively. In today’s world, consumers become more health conscious, their demands for functional dairy products are increasing rapidly. Functional dairy products occupy a significant space in the functional food market (Du et al., 2021).

DOI

https://doi.org/10.29321/MAJ.10.500024

Pages

110 - 118

Creative Commons

Copyright

© The Author(s), 2025. Published by Madras Agricultural Students' Union in Madras Agricultural Journal (MAJ). This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited by the user.

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