Combined Effects of γ-Irradiation and Ascorbic Acid on the Physicochemical Properties, Microbial Stability and Aroma Profile of Onion Puree During Storage

Abstract

The onion was first pureed and then added with 0.5% ascorbic acid before it was γ-irradiated at 2 kGy. The puree was then stored at 4, 10 and 27C for up to 28 days. Changes monitored included pH, titratable acidity, total soluble solids, color, total bacteria and yeast counts, organic acids and sensory property of the puree. Results show that the combined treatments reduced the contamination levels of the total bacteria and yeasts, and it helped to stabilize the color, and other physicochemical properties, such as pH, acidity, organic acid composition and contents of cold-stored onion puree. This study has shown that onion puree kept the initial color of fresh onion puree after 2 kGy γ-irradiation if it contained 0.5% ascorbic acid and storage at 4C for 28 days. PRACTICAL APPLICATIONSThermal treatment is a common method to reduce microbiological contamination. However, thermal treatment can diminish nutrient value of food and reduce the foods flavor and aroma. Nonthermal processing, such as additives and irradiation, that reduce microbial content without effects on flavor, color and nutrient value of the foods is developing. The present study investigated the combined effect of γ-irradiation and added ascorbic acid on yellow onion (Allium cepa Linnaeus, Lilliaceae).

Moisture sorption isotherm and shelf‐life prediction of anticaking agent incorporated spray‐dried soursop (Annona muricata L.) powder

“…The panelists were required to taste and rate the aroma, color, mouthfeel, taste, and overall acceptability of the samples based on a nine‐point hedonic scale ranging from “dislike extremely, 1” to “like extremely, 9.” Mineral water was provided to the panelists to rinse their mouths in between samples. The mean score for all sensory attributes was then calculated (Sadoughi, Karim, Hashim, Zainuri, & Ghazali, ).…”