Development of preliminary rapid screening index for honey adulteration based on the physicochemical property analysis
Journal
Taiwanese Journal of Agricultural Chemistry and Food Science
Journal Volume
56
Journal Issue
5
Pages
121-127
Date Issued
2018
Author(s)
Chen R.L.-C.
Hou Y.-T.
Cheng T.-J.
Lai Y.-J.
Tsai S.-T.
Abstract
Honey adulteration is a topic issue in the field of food authenticity. Although stable carbon isotope ratio analysis is commonly recognized to be the international standard procedure for honey adulteration, it is still too costly, time consuming, and laborious which is inapplicable to routine screening purposes. In the present work, 26 commercial blended honeys, 48 pure Longan honeys, and 23 pure Litchi honeys were collected to analyze their physicochemical properties including sugar content, pH value, electrical conductivity, color intensity, turbidity, proline content, and gluconate content. The threshold of each physicochemical property for discriminating between pure honeys and blended honeys was then designated according to the experimental data obtained above. After calculating the discrimination ratio, the applicable rapid screening indexes were selected for honey adulteration. It was revealed that sugar content, pH, and color intensity were not applicable to screen honey adulteration due to false negative results were found. Contrarily, electrical conductivity, turbidity, proline content, and gluconate content were proven to be the potentially applicable preliminary rapid screening indexes for honey adulteration. The suggested thresholds of electrical conductivity, turbidity, proline content, and gluconate content were set to be 170 μS/cm, 0.058, 180 mg/L, and 93 nM, respectively. Once any of the four rapid screening indexes was determined less than the corresponding thresholds, the sample was screened out as suspicious sample. Therefore, the negative samples could be substantially screened out accordingly, the remained positive samples were then verified by the stable carbon isotope ratio analysis to realize an ideal rapid screening method with the features of cost-effectiveness, easy-to-use, and time-saving.
Type
journal article