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Diastase Number Changes During Thermal and Microwave Processing of Honey

DOI:10.17221/123/2010-CJFS
Authors:
Stanisław Kowalski at University of Agriculture in Krakow
Stanisław Kowalski
Marcin Lukasiewicz at University of Agriculture in Krakow
Marcin Lukasiewicz
Szczepan Bednarz at Cracow University of Technology
Szczepan Bednarz
Marzena Panuś
Marzena Panuś
Marzena Panuś
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Abstract and Figures

The presented paper covers the preliminary studies on microwave inactivation of honey enzymes described as diastase number (DN). All the investigations were done on commercially available honey from Polish local market. Microwave processes were compared to the conventional ones. In the case of conventional conditions, the constant rate of diastase enzyme inactivation was estimated using the first order kinetics. In the case of microwave heated samples, it was impossible to establish the rate constant; however, the investigation proved the suitability of such kind of processing for short-term thermal treatment of honey.
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... Therefore, the adulteration of honey with different sugar syrups has a significant effect on the HMF content and can be used to evaluate the quality of raw and processed honey. [45,46] It is worth noting that processing honey at 60°C for 20 min increased the production of HMF content in the honey, which was much greater in cane syrup adulteration than other syrup types. [32][33][34] Furthermore, the addition of sugar syrups significantly reduced the diastase number (DN) in both raw and processed honey. ...
... This can be due to the heat treatment, which increased the total phenol content present in malt syrup. [42][43][44][45][46][47] The therapeutic and antibiotic properties of honey are due to the present phytochemicals and antioxidant properties. [45,53] Due to the adulteration of honey along with thermal processing, these beneficial components were destroyed, by which the functional value of honey was reduced and a reduction in the quality of respective honey. ...
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... In order to get rid of the crystallization, they expose it to mild heat treatment to dissolve the crystals. Glucose oxidase, diastase, invertase and other protective enzymes that act as antioxidants and antibacterial agents or purported to possess healing power are also degraded because of the heat generated by this treatment [39][40][41][42][43][44]. Furthermore, excessive microwave treatment decreases bioactive components, including antioxidant and anti-inflammatory activities in honey, denaturation of proteins, decreases vitamin content and decreases the freshness of honey [45,46]. ...
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  • Jul 2022
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... Using a water bath, Tualang honey was heated at 50, 70, and 90±2.5oC (Kowalski et al., 2012) for 1, 15, 30, and 60 min. The Tualang honey was sealed properly into clear glass containers (5.6 x 8.9 cm). ...
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Full-text available
  • Jan 2023
Conventional heating is a common treatment applied to honey to preserve its quality and facilitate packaging. The treatment will reduce the viscosity and moisture level of honey, destroy yeasts, liquefy crystals, and delay crystallisation. However, conventional heating may increase the hydroxymethyfurfural (HMF) content in honey which is a potential carcinogen to human and lead to quality deterioration. Alternatively, the use of ultrasound to treat honey can minimize the heat exposure. This study was conducted to determine the suitable process conditions to be applied to Tualang honey and to compare the quality of Tualang honey treated using two different techniques. The quality of honey was determined from physicochemical analysis (turbidity, colour, pH, water activity, and moisture content), and HMF analysis using White method. Tualang honey samples were treated at different conditions; 50-90oC for 1-60 min using conventional heating and 50-90% amplitude for 10-30 min using ultrasound technique. The best condition for each treatment was determined at 70oC for 15 min using conventional heating and 70% amplitude for 10 min using ultrasound treatment. This study also points out that the use of ultrasound treatment slowed down the HMF formation compared to conventional heating. It can be concluded that Tualang honey treated with ultrasound can be used by honey producers to retain the quality of honey.
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... Indeed, GOX and its enzymatic activity seems to be a more suitable quality standard than diastase activity, expressed as diastase number (DN), due to its high sensitivity to the thermal processing of honey. Several studies found that conventional heating of honey at 90 • C for 20-30 min did not cause extreme changes in the DN value and thus did not significantly affect its quality (Kowalski et al., 2012;Tosi et al., 2008). Moreover, Tosi et al. (2008) documented that DN was unreliable to examine thermally-treated honey due to its variable behaviour and due to the fact that diastase activity in honey can be recovered if thermal treatments were carried out at moderate temperatures for longer time (60 • C, 30 min). ...
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... 71 Diastase, an enzyme found in honey, is responsible for the breakdown of starch to maltose and is sensitive to heat, with exposure to higher temperatures resulting in reduced quantities of this enzyme in honey. 72 The increased content of diastase in raw honey may contribute to better digestion of starch in individuals who consume significant amounts of honey, leading to the beneficial effects reported in this study. Similarly, hydroxymethyl furfural, an organic compound found in honey, is often also used as an indicator of honey quality. ...
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... This showed that comb and processed honey can essentially be differentiated based on enzyme patterns that projected towards the comb honey; and antioxidants associated with processed honey. According to Kowalsk et al. (2012), comb honey had a relatively higher amount of enzymes, and the processing of honey possibly reduced the level of enzymes. Contrarily, the processing of honey is used to increase the antioxidant activity of honey, which is generated from the Maillard and caramelization reactions (Turkmen et al., 2005). ...
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