Determination of Antioxidant Capacity, Total Phenolics and Antimicrobial Properties of Spray-Dried Guava Extract for Value-Added Processing

Abstract

To explore the potential use of Guava as a functional food ingredient, aqueous guava extract was filtered to remove insoluble material; the soluble extract was spray-dried with the addition of 7% maltodextrin. Spray dried Guava concentrate showed increased levels of antioxidant capacity (2, 2-diphenyl-1-picrylhydrazyl DPPH assay 3.2 fold) and total phenolics (2.0 fold) but low levels of flavinoids. The addition of maltodextrin during spray-drying resulted in the formation of certain unresolved peaks analyzed by HPLC due to dilution effect, the redistribution of molecular weight is likely beneficial for in vivo absorption and increase its bioavailability. Spray-drying concentration also increased the proportion of ascorbic acid content (118.6 mg/100g) of guava powder and showed effective antimicrobial activity against Shigella (MIC 11mg/ml), E coli (MIC 8 mg/ml) and Candida spp. (MIC<1 mg/ml). The proximate and physiochemical properties showed good quality and increased solubility of guava powder compared to plain guava extract. Overall the spray-dried Guava powder may be a good source of natural antioxidants and profoundly increase use of Guava in value added processing and dietary intake.

Effectiveness of cardamom (Elettaria cardamomum) or bay leaf (Laurus nobilis L.) powder in improving the quality of Labneh

“…The TPC and TFC have redox properties, which act as hydrogen donors and singlet oxygen quenchers. These results are confirmed by Chauhan et al (2014) and Balabanova et al (2020).…”

Effectiveness of cardamom (Elettaria cardamomum) or bay leaf (Laurus nobilis L.) powder in improving the quality of Labneh [pdf]

“…The TPC and TFC have redox properties, which act as hydrogen donors and singlet oxygen quenchers. These results are confirmed by Chauhan et al (2014) and Balabanova et al (2020).…”

Current Status of Guava (Psidium Guajava L) Production, Utilization, Processing and Preservation in Kenya: A Review

“…69 There are many products which can be obtained from processing guavas including guava pulp, jam, juice, jelly chocolates, wine and guava powder (which is mostly used in preparation of yogurt) 3 and spray dried soluble guava extracts containing high concentration of antioxidants. 3,70 Some of the Commercial Products from Guava Include; Guava Pulp Processing of guavas into pulp provides a convenient form of guava fruits preservation. [71][72][73] The guava pulp can best be preserved by addition of potassium metabisulphite at low concentrations (0.005 -0.2%) and storing at low temperatures (2-5 o C) to avoid nutrient breakdown.…”