Acacia honey is one of the most popular honey varieties loved by people worldwide. While offering numerous medical and therapeutic benefits, it is the most common honey type sold in adulterated form by many commercial honey sellers due to rising demand. Romanian acacia honey is available in three forms: pure, directly adulterated, and indirectly adulterated. To get more insight about the characteristics of Romanian acacia honey, it was characterized and discriminated based on their physicochemical parameters. 

Honey composition and properties can be intensely affected by plant and topographical origin, environment, season, harvesting time, handling and storage conditions. Because of its high cost and restricted accessibility, honey is frequently subjected to adulteration. It can be made either directly, for the most part by blending in with various cheap sugar syrups (of sugar stick or beer, corn, rice, date, agave, inulin, reversed glucose,sugar, fructose), or indirectly, by feeding the honey bees with various sugars. The demand for pure, organic & raw honey has increased these days. In this specific circumstance, observing the most effective methods to detect honey adulteration is a vital issue.

Generally, honey adulteration is detected by measurement of applicable physicochemical parameters [e.g., dampness, debris, proline, 5-hydroxymethylfurfural (HMF), reducing sugar (RS) and non-reducing sugar (NRS) substance, electrical conductivity, diastase movement (DA), free acidity (FA), pH, rheological parameters. These targeted scientific strategies, which are usually performed by applying conventional science techniques, imply sample preparation to separate a compound/a group of compounds to decide its concentration. Progressed methods dependent on electrochemical examination, flow injection analysis, biosensors (e.g., e-tongue, e-nose), differential scanning calorimetry, gas and liquid chromatography (GC-FID, HPLC), mass spectrometry (GC–MS, LC–MS, IRMS), NMR and infrared (NIR, FT-IR, and Raman) spectroscopy have been developed during the last three decades for the detection of honey adulterants. Every technique used to detect adulteration enjoys its particular benefits and impediments. Conventional physicochemical analysis usually has high sensitivity and selectivity. They are habitually used in the honey trade, although some of them are relatively tedious and require complex gear.

Romania, an important honey producer and exporter in Europe, has an annual output of over 20,000 t in recent years, half of which is exported. Lime, acacia, sunflower, rape, and polyfloral honey varieties are liked by the Romanian people. Researchers have published a paper aiming to evaluate the ability of physicochemical analysis methods and chemometrics to differentiate between pure and adulterated Romanian acacia honey.

The research was carried out in a joint effort with a beekeeper from Vâlcea province of Romania, who consented to take an interest in the review with 12 hives (H1–H12), every one of them containing three colonies of Apis mellifera carpatica. As a result, three acacia honey types were prepared and investigated, i.e., pure or unadulterated (P), indirectly (I) adulterated by honey bee who were fed with sugar syrups, and directly (D) adulterated by blending Phoney with similar syrups.

Physiochemical Analysis – 

Physicochemical parameters as far as moisture content, FA, RS content, ash content, sucrose content, DA, and HMF content were determined dependent on Romanian standard SR 784-340. This standard was harmonized with Official strategies for the Association of Official Analytical Chemists (AOAC) investigation and Harmonized techniques for the European honey commission.

Statistical Analysis – 

Univariate (single direction ANOVA) and multivariate (PCA and LDA) examinations of physicochemical parameters were performed utilizing Statistica 10 (StatSoft, Inc) and XLSTAT 2019.1 (Excel). A normalized information matrix with 23 lines (number of tests) and eight segments (number of physicochemical boundaries) containing autoscaled variable qualities was utilized in PCA. To acquire the proper prescient characterization, in LDA, the examples were partitioned dependent on a determination calculation into a preparation set comprising of 16 examples and an approval set containing seven examples (one example of each honey kind, i.e., P, D1–D3, I1–I3).

Results – 

Moisture content is an applicable parameter as it influences the consistency, thickness, taste, flavour, colour, crystallization, and ageing of honey. High water content can speed up the crystallization as it produces ageing during storage. 

Ash or mineral substance is a marker influencing the colour and kind of honey. Usually, the honey with higher ash content is darker in colour and more robust in flavour.

FA is principal because of the presence of natural acids in harmony with lactones or interior esters and inorganic particles, e.g., chloride, sulfate, phosphate, and it can intensely impact the honey taste. An increment in FA can happen over the long haul as an impact of acid development (e.g., gluconic corrosive from glucose, formic and levulinic acids from HMF) just as on account of ageing. 

Adulteration prompted an expansion in water content (by around 10%), FA (7 times), sucrose content (2.6 and 1.7 times for I and D examples, individually), HMF content (around 25 and 18 times for I and D examples, separately), also a diminishing in RS content (by around 10%) and DA (2.8 and 2.1 times for I and D examples, individually) than the mean worth of P tests. For the kinds and measurements of sugar syrups utilized in this review, indirect adulteration had impacts like those produced by direct adulteration. The values of DA, HMF, sucrose, and RS substance for D and I honey examples were not inside the ranges imposed by the national standard.

Additionally, the assessment of physicochemical parameters utilizing PCA and LDA was exceptionally successful to separate between unadulterated, indirectly and directly adulterated honey. In light of the physicochemical parameters as far as DA, HMF, sucrose, and RS substance, any example of acacia honey could be classified as pure, directly or indirectly adulterated using classification functions obtained by applying LDA. According to Mr. Basem Barry, founder & CEO of Geohoney, the review has a few limitations, e.g., a few acacia honey examples, general comparability (all coming from the same producers and being delivered within a few months). The investigation could be broadened using various examples of different kinds of honey gathered from a few producers over a more drawn-out period.