TITLE:
The Antioxidant Activity of Barley Malt Rootlet Extracts in Heated Corn Oil at Frying Temperature
AUTHORS:
Sravanthi Budaraju, P. Kumar Mallikarjunan, A. Saari Csallany
KEYWORDS:
Antioxidant Activity, Autoclave Treatment, Barley Malt Rootlets, BHT, Bound and Free Phenolics, Corn Oil, Lipid Peroxidation, Microwave Assisted Extraction, Secondary Oxidation Products, Solvent Extraction
JOURNAL NAME:
Food and Nutrition Sciences,
Vol.12 No.9,
September
18,
2021
ABSTRACT: In this study the antioxidant activity of barley malt rootlet (BMR)
extracts was evaluated in heat treated corn oil up to 5 hours at 185°C
frying temperature. The antioxidant activity of BMR extracts was measured at 25, 50, 100 and 150 ppm
concentrations. The free and bound antioxidant phenolics were extracted from
BMR using three different extraction methods. Conventional solvent extraction
(CSE), microwave assisted extraction (MAE) and autoclave assisted pretreated
solvent extraction (APSE). In the present experiment, the total phenolic
content and antioxidant activity of the various extracts were measured. Thiobarbituric
acid reactive substances (TBARS) assay was used to evaluate the ability of the
BMR to protect lipid peroxidation in corn oil at 185°C frying temperature. The
formation of TBARS at 5 hours of heat treated corn oil has shown similar antioxidant
levels in 150 ppm butylated hydroxytoluene (BHT) or MAE free phenolic extract
added to corn oil. TBARS value for BHT was 1.896 ± 0.013 μg/mL of corn oil and
for MAE was 1.896 ± 0.034 μg/mL of corn oil. The highest level of antioxidant
activity was found for the free phenolic extracts. The order of inhibition of
oxidation was found to be for free phenolics as follows: BHT (100 ppm) >
APSE (50 ppm) > MAE (100 ppm) > CSE (100 ppm).