## 5 Authenticity, Processing and Adulteration for Apitherapy Use  
Because of its importance in terms of nutritional value and therapeutic effects, honey can be submitted to various fraud modalities in order to increase its production at lower price [53,220]. Therefore, there is a need for an increased European quality control approach, using safety protocols and standards that can guarantee its quality so as to be available for the purpose of apitherapy. The authenticity of honey can be assured by taking into consideration physicochemical properties and the obtaining, processing and storage conditions [32]. Moreover, other parameters can also affect the quality of honey, including the geographical origin of plants, harvesting period, correct labelling and the contaminant remnants [53,221]. Currently, there have been several recognised quality standards, as listed in both the European Council Directive 2001/110/EC [104] and the Codex Alimentarius Standard for Honey (2001) [222]. These quality standards refer to the maximum content of various parameters (water content, pH, electrical conductivity, 5-hydroxymethylfurfurral (5-HMF) content, diastase activity, colour, reducing and non-reducing sugars) [33,124] suggested for consumption and market purposes [168], as described in previous sections. These parameters can reveal useful information regarding the raw material origin and thus finding discriminating marker compounds for various uniforal honey varieties [52] or chemical parameters for distinguishing Blossom honey from Honeydew honey [33,41,43,58,100,223] as has been previously reported. Moreover, it is well-known that honey undertakes important composition changes during storage, due to the chemical reactions that occur in the presence of high temperature or long preservation conditions [9]. Among these reactions, 5-HMF and diastase [224] are considered key elements for the indication of honey freshness [88,225,226] or possible adulteration with inverted sugars [9]. Furthermore, the 5-HMF content in honey is established by the Codex Alimentarius Standard Commission (5-HMF in honey at 40 mg/kg and 80 mg/kg for tropical origin honeys). Different methods are used for analysing the composition of honey and identifying its authenticity, including physicochemical parameters assay [51], using linear discriminant analysis (LDA) [227] or carbon isotope ratios and trace elements [228] and pollen analysis (melisospalynological analysis) [100,229]. Other modern assets available for honey authentication are the chemometric procedure [224,230], mass spectrometry [231,232], high-performance liquid chromatography (HPLC) [233,234], spectroscopy (UV visible), near-infrared (NIR) [114,225], gas chromatography coupled with mass spectrometry (GC-MS) [235,236] or nuclear magnetic resonance (NMR) [237,238]. However, in the majority of cases, when evaluating the authenticity and traceability of honey samples, combined analytical methods are employed by using various clustering and classification algorithms [22,220]. Regarding processing beekeepers perform several activities that include extraction by pressing and centrifugation, filtration or storage [239] in order to produce commercial honey. During these procedures, the production and characteristics of honey can be modified. Based on this, beekeepers should follow some rules of good apicultural practices during all honey processing phases, as suggested by [PERSON] et al. (2005) [240] or more recently by [PERSON] (2017) [241]: personal hygiene and cleanness in the extraction room,equipment, instruments used, containers or surfaces that come into direct contact with honey; compatible materials for containers and processing equipment in order to avoid contamination (Cu, Fr, Zn or steel should be avoided as materials). An important aspect to consider regarding the beekeeper's management for assuring a high quality in honey is the avoidance to use drugs or chemicals that are banned or have restricted use at European level [242; 243].