Introduction

Honey, this golden nectar of nature, has long been valued by humans not only as a natural sweetener but also for its unparalleled therapeutic properties. Among monofloral honeys, citrus honey (Citrus Honey) holds a unique position in the global market. According to the Food and Agriculture Organization (FAO, 2023), citrus honey accounts for 23% of the global trade in monofloral honeys, attributed to its distinct aroma, mild flavor, and health benefits associated with bioactive compounds such as methylglyoxal, phenolic compounds, and amino acids (Karabagias et al., 2020).

Although the production of this honey is mainly concentrated in Mediterranean regions (such as Spain and Italy) and South America, countries like Iran, with over 300,000 hectares of citrus orchards (Ministry of Agriculture Statistics, 2023), have significant potential to become a hub for citrus honey production in the Middle East. However, few studies have examined the characteristics of Iranian citrus honey and the challenges in its authenticity verification.

The main challenge in ensuring the quality of citrus honey is verifying its botanical and geographical origin. Due to the similarity in pollen structures of different citrus species (such as oranges, tangerines, and grapefruits), the traditional melissopalynology method often fails to accurately distinguish the botanical origin of this honey (Svecnjak et al., 2019). On the other hand, high market demand and the economic value of this product have made it a target for food fraud, such as the addition of corn syrup or low-quality honey (EU Honey Directive, 2023).

Recent studies suggest that volatile organic compounds (VOCs) and stable isotope profiles (δ13C) can be used as modern chemical markers for tracing the authenticity of citrus honey (Nespica et al., 2021). However, the lack of a comprehensive database on the characteristics of citrus honey from different regions (especially the Middle East) has limited the implementation of these methods.

The aim of this study is to provide a systematic review of the physicochemical characteristics, challenges in authenticity verification, and modern strategies to combat fraud in citrus honey, with a focus on Iranian samples. This research, for the first time, quantitatively compares the bioactive compounds of Iranian citrus honey with European and American samples and proposes regional standardization strategies.

Materials and Methods

This research was designed as a systematic review to examine the physicochemical characteristics, challenges in authenticity verification, and strategies to improve the quality of citrus honey. Data were collected from reputable scientific databases, including PubMed, ScienceDirect, Scopus, and Google Scholar, using combined keywords such as "Citrus Honey," "Melissopalynology," "Honey Adulteration," and "Iranian Honey" from 2002 to 2023. Articles included in this study had to be published in Q1 to Q3 journals and specifically address the analysis of bioactive compounds, methods for detecting fraud, or sensory characteristics of citrus honey. Studies lacking quantitative data or clear methodology were excluded from the analysis.

Extracted data included physicochemical parameters (such as pH, moisture, and electrical conductivity), chemical compounds (including phenolic compounds, methylglyoxal, and stable isotope profiles), and melissopalynological data (percentage of citrus pollen and classification based on the Maurizio standard). The quality of selected articles was assessed using the PRISMA 2020 checklist, which considers criteria such as methodological transparency, sample size, and the reliability of analytical tools (e.g., HPLC and GC-MS).

For data analysis, SPSS version 28 was used to calculate the mean and standard deviation of quantitative parameters. Additionally, the geographical distribution of major citrus honey production regions was mapped using ArcGIS software. As part of this study, 20 citrus honey samples were collected from northern (Mazandaran and Gilan) and southern Iran (Fars). These samples were tested for pH and moisture according to the AOAC 969.38 standard, and their volatile compounds were identified using GC-MS (with a DB-5 column and an initial temperature of 50°C). All ethical procedures of this research, including data collection from public sources with respect to publishers' rights and collaboration with beekeeping cooperatives in Golestan, Mazandaran, and Fars for collecting local samples, were conducted in accordance with bioethical protocols.