Verification test of sensory analyses of comb and strained honeys produced as pure and feeding intensively with sucrose (Saccharum officinarum L.) syrup

The aims of the study were to discriminate comb and strained honeys produced by the standard beekeeping method (control), shaking method (pure blossom honey), and feeding intensively (100 kg/colony) with sucrose (adulterated honey) syrup by using sensory analysis and to develop a method to be used in identification of unknown or suspicion honey samples. In the study, twenty trained panelists assessed honey samples in relation to their properties including taste, odor, color, aroma, viscosity, dissolution in mouth, inflammation in throat, attractiveness, flavor and general impression during four months. There were no differences in odor, viscosity, and dissolution in mouth between comb and strained honey samples which produced by different methods (P > 0.05). Discrimination of strained honey by sensory analysis was more reliable when compared to comb honey. The ratio of correctly classified sample was 78.3% for comb and 86.7% for strained honey. The more honey was pure the more discrimination of honey sample by sensory analysis was reliable. In verification test five unknown honey samples were classified 100% in their real groups by using canonical discriminant function Coefficients of each properties evaluated and the projections of the sample points on the plane of the canonical function-1 and function-2.     

Dielectric properties of honey adulterated with sucrose syrup

Sucrose syrup is a common additive in honey adulteration. To provide information for developing a cheap, simple, convenient and rapid sucrose-adulterated honey detector or sucrose content sensor, the permittivities of pure jujube, yellow-locust and milk-vetch flower honey, pure sucrose syrup and honey-sucrose syrup mixtures with sucrose content from 0% (pure honey) to 80% (pure sucrose syrup) were studied from 10 to 4500 MHz with open-ended coaxial-line technology and a network analyzer at room temperature. The correlations between permittivities and sucrose contents were regressed. The results showed that the dielectric constants of all samples decreased with increasing frequency, while the pure honey had higher dielectric constant than pure sucrose syrup. Dielectric relaxation existed in all samples. The maximum loss factor decreased with increasing sucrose content. The relaxation frequency changed very little with sucrose content. Strong negative linear correlation, R² > 0.98, was found between loss factor around the relaxation frequency and sucrose content.     

Determination of Chinese honey adulterated with high fructose corn syrup by near infrared spectroscopy

The use of fibre optic diffuse reflectance near infrared spectroscopy (NIR) in combination with chemometric techniques has been investigated to discriminate authenticity of honey. NIR spectra of unadulterated honey and adulterated honey samples with high fructose corn syrup were registered within 10,000–4000 cm⁻¹ spectral region. Discriminant partial least squares (DPLS) models were constructed to distinguish between unadulterated honey and adulterated honey samples and main bands responsible for the discrimination of samples are in the range of 6000–10,000 cm⁻¹. For these models, the correct classification rate for calibration samples were above 90%. Hundred percentage of unadulterated honey and 95% of adulterated honey samples from test set were correctly classified after appropriate preprocessing of first derivative, 13 smoothing points, followed by mean centering pre-treatment and eight model factors, respectively. Our results showed that NIR spectroscopy data with chemometrics techniques can be applied to rapid detecting honey adulteration with high fructose corn syrup.     

电子舌对掺入果葡糖浆掺假蜂蜜的识别

采用电子舌对不同蜂蜜以及掺入果葡糖浆的蜂蜜样品进行测定,对所获得的数据进行主成分分析、判别因子分析和偏最小二乘回归分析。结果表明:电子舌能够区分不同蜂蜜样品和掺假蜂蜜样品(果葡糖浆掺入比例≥5%);对掺假蜂蜜样品建立了偏最小二乘回归分析预测模型,电子舌响应信号和果葡糖浆掺入比例之间有很好的相关性(决定系数R2为0.992 0),偏最小二乘回归分析模型预测误差均≤5%(掺入比例为10%~70%)。试验证明电子舌可用于掺入果葡糖浆的掺假蜂蜜的识别。     

Classification of simple and complex sugar adulterants in honey by mid-infrared spectroscopy

Adulteration of honey with sugars is the most crucial quality assurance concern to the honey industry. The application of Fourier transform infrared spectroscopy as a screening tool for the determination of the type of sugar adulterant in honey was investigated. Spectra of honey adulterated with simple and complex sugars were recorded in the mid-infrared range using the attenuated total reflectance accessory of a Fourier transform infrared spectrometer. Adulterants considered were sugars (glucose, fructose and sucrose) and invert sugars (cane invert and beet invert). Predictive models were developed to classify the adulterated honey samples using discriminant analysis. Spectral data were compressed using principal component analysis and partial least-square methods. Linear discriminant analysis was used to discriminate the type of adulterant in three different honey varieties. An optimum classification of 100% was achieved for honey samples adulterated with glucose, fructose, sucrose and beet and cane invert sugars. Results demonstrated that discriminant analysis of the spectra of adulterated honey samples could be used for rapid detection of adulteration in honey.     

Quantitative analysis of physical and chemical measurands in honey by mid-infrared spectrometry

Fourier transform infrared spectroscopy (FT-IR) was used to determine 20 different measurands in honey. The reference values for 144 honey samples of different botanical origin were determined by classical physical and chemical methods. Partial least squares regression was used to develop the calibration models for the measurands studied. They were validated using independent samples and proved satisfying accuracies for the determination of water (R ²=0.99), glucose (0.94), fructose (0.84), sucrose (0.91), melezitose (0.98) and monosaccharide content (0.82) as well as fructose/glucose ratio (0.98), glucose/water ratio (0.94), electrical conductivity (0.98), pH-value (0.87) and free acidity (0.96). The prediction accuracy for hydroxymethylfurfural, proline and the minor sugars maltose, turanose, erlose, trehalose, isomaltose and kojibiose was rather poor. The results demonstrate that mid-infrared spectrometry is a valuable, rapid and non-destructive tool for the quantitative analysis of the most important measurands in honey.     

官能团保留指数鉴别掺淀粉糖浆蜂蜜的研究

研究了利用官能团保留指数法(Kovats index)鉴别掺淀粉糖浆的假蜂蜜。蜂蜜样品溶于水后用凝胶(Bio-Gel?P-2 Gel)体积排阻法去除样品中果糖、葡萄糖,将寡糖富集后直接经阴离子交换色谱电化学检测器检测。直链麦芽寡糖是由葡萄糖单体缩合而成的寡糖,类似正构烷烃,将麦芽寡糖(二糖~七糖)标准样品色谱峰作为对照峰,将麦芽四糖、五糖、六糖、七糖的保留指数分别设为400、500、600、700,根据样品获得的色谱峰的保留时间计算官能团保留指数值,结果表明,在添加果葡糖浆的麦芽糖混标样品、掺有果葡糖浆的纯蜂蜜及部分市售蜂蜜样品均出现相同的官能团保留指数值,而纯蜂蜜样品不存在此现象,据此可判断蜂蜜是否掺假,灵敏度可达1%。利用该结果对已知掺假的蜂蜜进行验证,结论符合。     

Effects of carbohydrate and noncarbohydrate sweeteners on the orange spirit volatile compounds

Various carbohydrates are permitted to sweeten spirits, whereas noncarbohydrates sweeteners are not currently approved for use. The effect of the addition of sucrose, glucose, fructose, honey, maple syrup, acesulfame K, aspartame and sorbitol on the flavor compounds of orange spirit has been studied by HS-SPME-GC analysis. Nine volatile compounds resulted affected by the sweetening: 2 aldehydes (acetaldehyde, benzaldehyde), 3 esters (ethyl-octanoate, ethyl-nonanoate and n-octyl-acetate), 2 alcohols (nonanol and linalool) and 2 hydrocarbons (δ-3-carene and valencene). Fructose, honey, acesulfame K and sorbitol had no effect on volatiles relative to an unsweetened control unlike sucrose, glucose, maple syrup and aspartame that decreased significantly (P?0.05) the headspace concentration of some volatiles. These results could be of assistance for an understanding of the role of sweeteners in the determining the extent of the volatile partition in the vapor phase affecting the flavor perception of the orange spirit.     

Sugar profile and physicochemical properties of Ethiopian monofloral honey

Three hundred twenty honey samples were collected from Ethiopia, and categorized into nine monofloral honeys using melissopalynology. Theses monofloral honeys were investigated for their sugar profile, physicochemical properties, and quality of honeys. Sugars (fructose, glucose, sucrose, maltose, turanose, and isomaltose) were identified using high-performance liquid chromatography and physicochemical properties (moisture, water activity, pH, acidity, ash, minerals, conductivity, colour) using the Harmonized Method of the International Honey Commission. Moisture and water activity showed a strong regression coefficient (r² = 0.92). Moisture content alone did not sufficiently describe the quality of honey during storage and processing.     

基于电子鼻技术鉴别蜂蜜掺入果葡糖水的研究

采用电子鼻对掺假蜂蜜样品进行分析,对所获得的数据进行主成分分析和偏最小二乘回归分析,对掺假蜂蜜样品建立了偏最小二乘回归分析预测模型。结果表明:电子鼻响应信号和果葡糖水掺入比例之间有很好的相关性(决定系数R2为0.980 3),偏最小二乘回归分析模型预测误差均≤8%(掺入比例20%~70%)。试验证明当果葡糖水掺入比例较高时,电子鼻可用于掺假蜂蜜的识别。     

Detection of honey adulteration with beet sugar using stable isotope methodology

A usual aspect of our work involves the analysis of honey samples for later sale, following current Spanish legislation. Such analyses essentially consist of studying pollen sediments, and sensory and physicochemical analyses. With this background, it seemed appropriate to investigate possible adulterations due to the addition of sugar (beet and cane). To do this, we selected 49 samples of honey obtained from 14 floral types and used them for pollinic and sensory analyses and to detect possible adulterations due to the addition of beet sugar products (treating the oligosaccharide fraction contained in the honey with the galactose oxidase reaction) or due to corn syrup addition (with normal δ¹³C stable carbon isotope ratios). After classifying the samples according to the results of the pollen and sensory analyses, further assays were conducted. From the results it was concluded that 15% of the samples had been adulterated with beet sugar and 4% with cane sugar. The implementation of many analyses for each sample means that the results can be intercorrelated very well.     

Honey Adulteration Detection Using Raman Spectroscopy

In this study, the Raman spectroscopy was used to detect honey adulterated with fructose (F), glucose (G), inverted sugar (IS), hydrolyzed inulin syrup (IN), and malt must (M). Thus, 56 samples of authentic honeys (acacia, sunflower, tilia, polyfloral, and honeydew) and 900 adulterated samples (with 5, 10, 20, 30, 40, and 50% fructose, glucose, inverted sugar, malt must, and hydrolyzed inulin syrup) were analyzed. The classification of honey authenticity has been made using the partial least square linear discriminant analysis (PLS-LDA), and a total accuracy of 96.54% (authentic honey vs. adulterated honey) was observed, while in the case of adulterated honey, a total accuracy of 90.00% was observed, respectively. The determination of the adulterant agent concentration has been made using partial least squares regression (PLSR) and principal component regression (PCR) methods. The proposed method can be considered easy and rapid for honey adulteration detection to provide continuous in-line information.     

Isotope Ratio Mass Spectrometry Coupled to Element Analyzer and Liquid Chromatography to Identify Commercial Honeys of Various Botanical Types

The aim of the present work was to investigate whether honeys of various botanical characteristics could be discriminated and identified on the basis of the isotopic data. For this purpose, 45 commercial honey samples of various botanical types were analyzed using isotope ratio mass spectrometry (IRMS) coupled to element analyzer (EA) and liquid chromatography (LC). δ ¹³C values of honey; corresponding extracted protein and individual sugars (sucrose, glucose, and fructose) of honey; reducing sugar; and sucrose contents were determined and utilized to demonstrate the authenticity of commercial honeys of different botanical types. Results indicated that a very strong correlation (δ ¹³C_protein = 0.862δ ¹³C_honey + 0.800, R ² = 0.944) was observed between δ ¹³C honey values and δ ¹³C protein values of real honey samples. δ ¹³C_honey and δ ¹³C_protein should range from ?27.2 to ?23.5 and ?26.9 to ?23.6‰ for pure honeys of various botanical types investigated in this study. The use of isotopic compositions and some systematic differences as authenticity criterion permits the honey samples of various botanical types to be reliably detected.     

蜂蜜搀假的物理鉴别法初探

通过常见物理特性及流变性差异鉴别蜂蜜是否搀假.在室温下按常见方法向蜂蜜中搀入蔗糖、CMC-Na、果胶、淀粉、氯化钙、尿素和水,然后测定其pH、电导率、糖度、粘度、密度及流变性.实验结果表明,纯蜂蜜与搀假蜂蜜都属于非牛顿流体;搀蔗糖蜂蜜用流变性难以鉴别,只能通过加水后粘度变化鉴别;其余搀假蜂蜜可通过其流变性和某些物理性能不同而与纯蜂蜜区分开.     

C/C pattern of honey from Turkey and determination of adulteration in commercially available honey samples using EA-IRMS

Honey adulteration particularly by adding cheap sugars such as High Fructose Corn Syrup (HFCS) and cane sugar syrup into natural honey is widespread. This study reports (¹³C/¹²C, ‰) patterns of 31 authentic honey samples obtained from different sources and regions of Turkey as well as 43 commercial honey samples to determine the adulteration using mass spectrometer coupled to elemental analyzer (EA-IRMS). The analyses indicated that the ranges of (¹³C/¹²C, ‰) values of honey and protein fractions of Turkish honey are from −23.30 to −27.58‰ and −24.13 to −26.76‰, respectively. These values for commercial honey samples were determined to range from −11.28 to −25.54‰ and −19.35 to −25.61‰, respectively. The numbers of adulterated commercial honey samples were found to be 10, which corresponds to 23% of the total number of the samples. Diastase activity, HMF content, electrical conductivity and moisture content of honey samples were also determined. Method validation and uncertainty budget calculations were also reported.     

Quantitative determination of physical and chemical measurands in honey by near-infrared spectrometry

Fourier transform near-infrared spectroscopy (FT-NIR) was evaluated to quantitatively determine 24 different measurands in honey. The reference values of 421 honey samples of different botanical origins were determined by classical physical and chemical methods. Partial least squares regression was used to develop the calibration models for the measurands studied. These calibrations were then validated using independent samples and proved satisfying accuracies for the determination of water (standard error of prediction: 0.3 g/100 g), glucose (1.3 g/100 g), fructose (1.6 g/100 g), sucrose (0.4 g/100 g), total monosaccharide content (2.6 g/100 g) as well as fructose/glucose ratio (0.09) and glucose/water ratio (0.12). The prediction accuracy for hydroxymethylfurfural, proline, pH-value, electrical conductivity, free acidity and the minor sugars maltose, turanose, nigerose, erlose, trehalose, isomaltose, kojibiose, melezitose, raffinose, gentiobiose, melibiose, maltotriose was poor and unreliable. The results demonstrate that near-infrared spectrometry is a valuable, rapid and non-destructive tool for the quantitative analysis of some measurands related to the main components in honey.     

Sensory attributes of low‐fat strawberry yoghurt as influenced by honey from different floral sources,sucrose and high‐fructose corn sweetener

Low‐fat strawberry yoghurts were prepared with each of five alternative sweeteners: sucrose, high‐fructose corn syrup and honey from three different floral sources. A ninety‐nine‐member consumer panel evaluated the yoghurts for flavour, aroma, sweetness and overall acceptance. Degree of liking was scored by the panellists on a nine‐point hedonic scale. Panellists preferred sucrose‐sweetened yoghurts over those sweetened with high‐fructose corn syrup and honey (P < 0.05). Among the honey‐sweetened yoghurts, sage honey was the most liked (P < 0.05), followed by alfalfa‐ and sourwood‐sweetened yoghurts.     

利用糖类成分评价我国油菜原蜜的品质

目的以油菜原蜜为研究对象,通过测定其中果糖、葡萄糖、蔗糖和麦芽糖的含量评价我国大宗原蜜的品质。方法采用高效液相色谱示差折光法测定我国10个省份共36种油菜原蜜样品中果糖、葡萄糖、蔗糖和麦芽糖的含量。结果用液相色谱方法测定蜂蜜中的果糖、葡萄糖、蔗糖和麦芽糖,最低检测限分别为0.079 g/100 g、0.018 g/100 g、0.037 g/100 g及0.094 g/100 g,定量检测限分别为0.263 g/100 g、0.061 g/100 g、0.124 g/100 g及0.314 g/100 g。36种油菜原蜜中果糖、葡萄糖、蔗糖和麦芽糖的含量范围分别为26.00~38.16g/100 g、23.65~39.68 g/100 g、0.14~0.62 g/100 g及1.09~3.10 g/100 g。结论油菜原蜜样品中的蔗糖含量都符合我国蜂蜜国家标准,但其中31.8%的样品中葡萄糖和果糖总量低于国家标准。目前,我国大宗蜂蜜不存在人为掺入蔗糖的问题。     

Differentiation of blossom and honeydew honeys using multivariate analysis on the physicochemical parameters and sugar composition

Multivariate analysis was applied on physicochemical parameters (moisture, water activity, electric conductivity, colour, hydroxymethyl furfural, acidity, pH, proline, diastase and invertase), sugar composition (fructose, glucose, sucrose, maltose, isomaltose, trehalose, turanose and melezitose) and palinological parameters determined in blossom and suspected honeydew honeys in order to differentiate them. The majority of the physicochemical, sugar composition and palinological parameters evaluated presented significant differences in the mean values between the suspected honeydew and blossom honeys, with the exception of moisture, water activity, diastase, fructose and maltose. Blossom honey samples tend to differentiate from the suspected honeydew honeys after applying factor analysis on the physicochemical parameters and sugar composition. Stepwise linear discriminant analysis allows the correct classification of all blossom honeys, and only one honeydew honey was erroneously included as blossom honey. So, the use of multivariate analysis on physicochemical parameters and sugar composition can be a useful tool to differentiate these types of honeys.     

Characterisation of honey produced from different fruit plants of northern India

Studies were carried out to determine the affect of different fruit plant sources viz., Litche chinensis (litchi), Citrus sinensis (sweet orange), Ziziphus mauritiana (ber) and Prunus persica (peach) on moisture content, pH, free acidity, reducing sugars and sucrose contents, fructose/glucose ratio, ash and proline content, invertase and diastase activities, hydroxymethylfurfural and mineral (sodium, potassium, iron, calcium, zinc, and copper) contents as well as on rheological properties of honey. The source of honey had a significant (P < 0.05) effect on moisture content, free acidity, reducing sugar, fructose/glucose ratio, hydroxymethylfurfural content, invertase and diastase activities, sucrose content, proline content, ash content, pH and mineral content. The honey from various sources exhibited Newtonian behaviour and the activation energy ranged from 63.63 to 81.48 kJ mol^?1. Pattern recognition methods such as principal component analysis andlinear discriminate analysis were performed to classify honey on the basis of physico‐chemical properties and mineral content. The variables proline, potassium and free acidity exhibited higher discrimination power.