Developing Radio-Frequency Roasting Protocols for Almonds Based on Quality Evaluations.

Foods

Department of Food Science, National Ilan University, Number 1, Section 1, Shen-Lung Road, Yilan 26041, Taiwan.

Published: June 2022


Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

Hot air roasting is a popular method for preparing almonds, but it takes a long time. We roasted almonds via dielectric heating using 5 kW, 40.68 MHz batch radio-frequency (RF) equipment and analyzed their quality and aroma using a gas chromatography/ion mobility spectrometer and sensory evaluation. Almonds with an initial moisture content of 8.47% (w.b.) were heated at an RF electrode gap of 10 cm; the target roasting temperature of 120 °C was achieved at weights of 0.5, 1, 1.5, and 2 kg for 4, 3.5, 7.5, and 11 min, respectively; and the moisture content was reduced to less than 2% (w.b.). For comparison, 1 kg of almonds was roasted in a 105 °C conventional oven for 120 min. The darker color and lower moisture content, water activity, and acid value of the RF-roasted almonds were favorable for preservation. The aroma analysis using gas chromatography/ion mobility spectroscopy (GC-IMS) revealed that the aroma signal after roasting was richer than that of raw almonds, and principal component analysis (PCA) demonstrated that the aromas of roasted and commercial almonds were similar. The RF-roasted almonds presented a better flavor, texture, and overall preferability compared to commercial almonds. RF heating could be used in the food industry to roast nuts.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9265784PMC
http://dx.doi.org/10.3390/foods11131885DOI Listing

Publication Analysis

Top Keywords

moisture content
12
almonds
10
gas chromatography/ion
8
chromatography/ion mobility
8
rf-roasted almonds
8
commercial almonds
8
developing radio-frequency
4
roasting
4
radio-frequency roasting
4
roasting protocols
4

Similar Publications

Physicochemical, microbiological, and microstructural changes in germinated wheat grain.

PLoS One

September 2025

Department of Science, LLP "Research and Production Enterprise "Innovator", Astana, Kazakhstan.

This study investigates the physicochemical, microbiological, and microstructural changes in soft wheat grain during germination under varying moisture conditions: moderately dry, moist, and wet. Pre-harvest sprouting can severely compromise grain quality and usability; however, understanding germination-induced changes offers insights into potential utilization strategies. Physical parameters-including thousand-kernel weight, test weight, and falling number-showed strong correlation with germination time, decreasing by 8.

View Article and Find Full Text PDF

The water activity of milk powders is a critical parameter for predicting quality and safety, but some retailers in the supply chain may be limited to measuring moisture content, which can be easier and more affordable. Moisture sorption isotherms relate moisture content to the corresponding water activity. In this study, moisture adsorption and desorption isotherms were determined for nonfat dry milk (NFDM) and milk protein concentrate (MPC-85) powder samples at ambient and elevated temperatures via the modernized dynamic dewpoint isotherm (DDI) method.

View Article and Find Full Text PDF

This study presents a biopreservation method using sourdough co-fermented with Fructilactobacillus sanfranciscensis and Propionibacterium freudenreichii, optimizing conditions to 220 hydration and 24 h fermentation. The composite sourdough bread quality was evaluated through physicochemical, storage, sensory, and microbial tests, with mechanisms analyzed based on microstructure, rheology, and dough structure. Results showed that: first, the composite sourdough enhanced bread physicochemical properties, increasing volume, height-to-diameter ratio, elasticity, and resilience, while reducing baking loss, hardness, chewiness, and adhesiveness.

View Article and Find Full Text PDF

Domiati cheese, one of the most popular soft white cheeses, is particularly susceptible to microbial deterioration due to its high moisture content and low salt concentration. This study assesses the effectiveness of a new edible coating made from carboxymethyl chitosan nanoparticles loaded with pomegranate peel extract (CCS LP) in increasing the shelf life of Domiati cheese. The study compares CCS LP's performance to pomegranate peel extract (PPE) and carboxymethyl chitosan nanoparticles (CCS NPs) alone.

View Article and Find Full Text PDF

The spoilage of bulgur, characterized by a distinctive off-odor, poses a significant challenge to the bulgur industry, resulting in an annual production loss of 10 %. The tempering process plays a critical role to prevent this problem. This study investigated spoilage under high-moisture tempering conditions (15-27 % moisture, 25, 35 and 45 °C, 0-12 h), focusing on off-odor formation, volatile compounds and microbial activity.

View Article and Find Full Text PDF