The present study aimed to evaluate the physicochemical characteristics of honey (raspberry, mint, rape, sunflower, thyme and polyfloral) produced in Romania. The honey samples were from the 2017 to 2018 harvest and were subjected to melissopalynological analysis, alongside the determination of the following physicochemical parameters: moisture content, pH, free acidity, electrical conductivity (EC), hydroxymethylfurfural (HMF) content, color, total polyphenols content (TPC), flavonoids content (FC), DPPH radical scavenging activity, phenolic acids, flavonols, sugars and organic acids in order to evaluate the usefulness of this parameters for the classification of honey according to botanical origin. The results of the melissopalynological analysis revealed that five types of honey samples had a percentage of pollen grains above the minimum of 45%, which was required in order to classify the samples as monofloral honey. The total polyphenols content reached the maximum value in the case of dark honey such as mint honey, followed by raspberry, thyme and polifloral honey. Fructose, glucose, maltose, sucrose, turanose, trehalose, melesitose, and raffinose were identified and quantified in all samples. Gluconic acid was the main organic acid in the composition of all honey samples. Principal component analysis (PCA) confirmed the possibility of the botanical authentication of honey based on these physicochemical parameters.Foods 2020, 9, 306 2 of 22 authentication of the botanical and geographical origin. Monofloral honey is more expensive than polyfloral honey; honey labeled as having a certain floral origin must come entirely or largely from the specific floral source and exhibit the organoleptic, physicochemical and microscopic characteristics of the honey source, as provided in international food standards [2,11].Considering that bees feed on various plants, pure monofloral honey is generally very rare. The identification of the origin of honey and the proof of its authenticity has become an important problem with the globalization of the honey market, involving about 150 countries [13]. The interest in identifying the floral origin of honey has increased in recent years due to the high preference of consumers for certain types of honey. Consumer preferences often vary depending on different sensory perceptions and medicinal properties. Thus, numerous research has been published to date, which aimed to develop reliable methods for indicating the floral origin of honey [14].Pollen analysis can be successfully used for the identification of the floral origin of honey. Therefore, melissopalinology should usually be supplemented by physicochemical and organoleptic analysis. Thus, to classify honey by botanical origin, a global interpretation of all results is required [15]. The melissopalynological analysis consists of counting the pollen grains and classify the honey according to its principal pollen grain percentage, for some honey such as sunflower, raspberry, rape and mint the principal pollen must reach at least...

The present study describes the extraction of total monomeric anthocyanin (TMA) and total phenolic content (TPC) from eggplant peel using ultrasonic treatments and methanol and 2-propanol as extraction solvents. The extraction yields were optimized by varying the solvent concentration, ultrasonic frequency, temperature and time of ultrasonic treatment. Box-Behnken design was used to investigate the effect of process variables on the ultrasound-assisted extraction. The results showed that for TPC extraction the optimal condition were obtained with a methanol concentration of 76.6%, 33.88 kHz ultrasonic frequency, a temperature of 69.4 °C and 57.5 min extraction time. For TMA the optimal condition were the following: 54.4% methanol concentration, 37 kHz, 55.1 °C and process time of 44.85 min.

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Six non-conventional techniques (microwave-assisted extraction -MAE, ultrasound-assisted extraction -UAE, enzyme-assisted extractionwith cellulase, EAE1, and Celluclast 1.5L, EAE2, ultrasound-assisted extractionheating treatment -UAEH, and enzyme-assisted extractionultrasound treatment -EAU) and conventional citric acid extraction -CE were applied to extract pectin from Malus domestica 'Fălticeni' apple pomace, and were compared in terms of extraction yield and physicochemical properties of pectin. MAE led to the highest extraction yield and ; the lowest pectin recovery was found for EAE2. Pectin samples obtained by MAE showed color parameters comparable to commercial apple (AP) and citrus (CP) pectin, and had high galacturonic acid content, increased equivalent weight and high degree of esterification. High galacturonic acid content and degree of esterification were also found in UAE pectin samples. On the opposite side, EAE1, EAE2 and EAU pectin had high equivalent 2 weight, but lower degree of esterification that classified EAE1 and EAU pectin as lowmethoxylated pectin. UAEH and MAE pectin showed thermal properties that were similar toto that of commercial AP and CP . The rheological characterization of pectin samples highlighted the high viscosities of UAE and MAE pectin solutions, which were positively correlated with their galacturonic acid content.