Search Results

You are looking at 1 - 3 of 3 items for

  • Author or Editor: Hoa Xuan Mac x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract

In this work, the simulated adulteration of coconut drink by dilution with water was investigated using laser-light backscattering (LLB) imaging. The laser vision system consisted of six low power laser modules, emitting 1 mm diameter beams at wavelengths of 532, 635, 780, 808, 850 and 1,064 nm. The backscattering images were acquired by a grey scale camera with 12 bit resolution. Eight parameters were extracted to describe the backscattering profile. The methods of linear discriminant analysis (LDA) and partial least squares (PLS) regression were performed on LLB parameters for classifying and predicting dilution level of adulterated coconut drink samples. Based on the results, LLB signals responded sensitively to adulteration. LDA results showed that adulterated samples were correctly recognized with accuracies between 60 and 100%. PLS models were able to estimate the adulteration level of samples with coefficients of determination of 0.57–0.97 in validation. This result demonstrated the potential of laser-light backscattering imaging as a rapid and non-destructive optical technique for evaluation of coconut drink adulteration.

Open access
Progress in Agricultural Engineering Sciences
Authors:
Thi Thanh Nga Ha
,
Thanh Tung Pham
,
Sao Mai Dam
,
Xuan Hoa Mac
,
Le Phuong Lien Nguyen
,
Géza Hitka
, and
Tamás Zsom

Abstract

This study focuses on the contribution of maturity stages and 1-methylcyclopropene (1-MCP) treatment to the quality of ‘Zebra’ apricot. Samples were harvested at mature-green, yellow and orange maturity stages. Fruit were treated with gaseous 1-MCP (24 h at 1 °C), followed by cold storage at 1 °C for 6 weeks. Non-destructive measurements were used to evaluate the quality changes of apricot during storage. The results showed that the maturity stages significantly affected the weight loss. The loss of weight increased rapidly for orange ripeness stage fruit, more than others during storage. Both maturity and 1-MCP affected the stiffness of apricot. The 1-MCP could delay the softening of fruit. The green and yellow maturity stages retained higher values in stiffness compared to orange. No significant difference in hue angle values was observed between 1-MCP treated and control fruit, however hue angle value decreased strongly in mature-green harvested fruit. The maturity stages and 1-MCP treatment had the effect on quality changes of apricot over storage. The maturity stage was an important factor contributing to the effectiveness of 1-MCP application as it was observed in slower softening after harvest.

Open access
Progress in Agricultural Engineering Sciences
Authors:
Thanh Tung Pham
,
Zinabu Hailu Siyum
,
Thi Thanh Nga Ha
,
Hoa Xuan Mac
,
Sao Mai Dam
,
Trang Ha Dieu Nguyen
,
Lien Le Phuong Nguyen
, and
László Baranyai

Abstract

The presented study investigated the effects of edible coatings with concentration of 2%, 3% and 4% of starch (w/v) on the weight loss and firmness loss of green asparagus during 4 days of storage at room temperature (26 ± 2 °C, 65–70% RH). According to the results, the coated asparagus exhibited significantly slower deterioration rate than the uncoated control samples. This was indicated by the decrease in weight loss and increase in firmness (P < 0.05). After the storage period, the samples treated with 4% starch formula retained the highest quality. Furthermore, the assessment of asparagus quality throughout the storage period involved the use of the line laser scattering technique. Extracted parameters of laser scattering signal discriminated samples with linear discriminant analysis (LDA), in which the correct recognition rate of the treated groups was 75.26% and the storage time was 70.54%. This study showed the potential of laser scattering as a rapid, non-invasive, and practical optical method for assessing the quality of asparagus during storage.

Open access