European Food Research and Technology最新文献

Chlorogenic acids (CQAs), a large family of naturally occurring esters of quinic acid with one, two or even three cinnamic acids moieties and/or moieties of cinnamic acids derivatives, supplied to human organisms mainly with coffee, tea, fruit and vegetables, have been among the most frequently studied polyphenols. Of these, caffeic acid esters predominate, and 5-O-caffeoylquinic acid (5-CQA) is their main and most widespread representative. Recently performed studies have shown that after removing water from the aqueous solution of 5-CQA, its dry residue contains two hydrates of this compound, each consisting of two 5-CQA molecules and two molecules of H₂O (2 × 5-CQA*2xH₂O). The results presented in the paper not only define the characteristic features of 5-CQA but, more importantly, offer solid evidence that 5-CQA hydrates begin to form already in the aqueous solution of 5-CQA immediately after the dissolution of this compound and that the analogous process can occur in food products containing 5-CQA during their storage. Moreover, the performed experiments indicate the validity of the hypothesis that 5-CQA hydrates are formed by active collisions of 5-CQA molecules with monomeric/dimeric water molecules existing in trace amount in strongly associated aqueous systems. The presence of 5-CQA hydrates in liquid food products may have a significant impact on the assessment of some of their physicochemical properties as well as their biochemical activity.

Beehive products, particularly pollen, are among the foodstuffs that may contain pyrrolizidine alkaloids (PAs), prompting concern due to their negative effects on humans, such as hepatotoxic potential. Based on these aspects, this study represents the first investigation into eight PAs present in samples of bee bread (n = 16) and commercial pollens (n = 15) from Brazil utilizing liquid chromatography coupled to mass spectrometry in tandem. Our findings showed the presence of at least two PAs in all samples analyzed (n = 31), with monocrotaline, senecionine, senecionine N-oxide, and retrorsine emerging as the most frequently abundant in the Brazilian samples. The PAs sum varied widely (from 268 to 263,849 µg kg⁻¹), with 77.4% of the samples exceeding the maximum limit established by the European Union (500 µg kg⁻¹). Therefore, this study demonstrates that bee pollen and bee bread are foods with high levels of PAs and highlights that further studies related to PAs and beehive products are necessary so that actions are taken to minimize risks to consumers and safeguard the beekeeping industry.

Dark chocolate presents exclusive characteristics that make it a food product with worldwide consumption and also as an ingredient in several food industries. Although chocolate is an energy-dense food, it is also rich in bioactive compounds and recent studies have demonstrated health benefits from a moderate consumption. Therefore, the quantification of the bioactive compounds of different types of cocoa, from different geographical origins, is of great importance to recognize the importance of single origin dark chocolate from the nutritional point of view. Dark chocolate produced from Amelonado variety presented higher values of hardness (5592 g), plastic viscosity (2.87 Pa.s) and yield value (12.91 Pa). Both dark chocolates from Peru, Piura Blanco and Chuncho, presented higher results in total phenolic content, total antioxidant capacity, caffeine and vitamin E. Additionally, sample Piura Blanco presented a higher content of theobromine (720.7 mg/100 g), lactic acid (1153.2 mg/100 g), succinic acid (679.4 mg/100 g) and oxalic acid (468.5 mg/100 g). On the other hand, chocolate from São Tomé presented a higher content of sucrose (38.22%) and SFA (62.38% of total fat). The results obtained demonstrate the existence of heterogeneity in cocoa varieties, supporting decision-makers in the selection of the most suitable cocoa for specific market needs.

The present work aimed to evaluate three varieties of peanut (Arachis hypogaea L.) regarding the content of anthocyanins and total phenolics, antioxidant activity, phenolic profile and the alkaloids trigonelline and theobromine. The total phenolic content was analyzed by the Fast-Blue and Folin–Ciocalteau methods, while the antioxidant activity was analyzed by the β-carotene/linoleic acid, ABTS⁺ and FRAP methods. The phenolic profile and alkaloids were determined using high performance liquid chromatography (HPLC–DAD-UV–Vis). Peanuts with beige shells stood out with higher antioxidant activity and total phenolic content, while peanuts with purple shells stood out with higher anthocyanin content. Eight phenolic compounds and the alkaloids trigonelline and theobromine have been identified in peanut varieties. However, only four phenolics (gallic, syringic, ferulic and transcinnamic acids), in addition to the two alkaloids, were identified simultaneously in the three varieties studied. Chlorogenic acid was absent in red and purple-seeded varieties, catechin and resveratrol in varieties with red and beige coats, and p-coumaric acid in those with beige coats. For the first time, trigonelline and theobromine were identified in peanuts. Therefore, the bioactive composition and antioxidant activity of peanuts depend on its genotype.

This study investigated the performance of liquid smoke food flavouring on sensory perception and consumer acceptability using sirloin steak. The liquid smoke was prepared by a fast pyrolysis process with kanuka wood. Various liquid smoke concentrations and marination times were applied for the smoking treatments. The descriptors of sensory attributes were summarised by focus group tests and illustrated by a word clouds method. The sensory evaluation by check-all-that-apply (CATA) tests and principal component analysis (PCA) revealed that the sample marinated with 3% (w/w) liquid smoke concentration for 30 min was highly preferred by the panel. Correlation analysis revealed that overall liking was positively correlated with odour and flavour liking, and they were the most critical factors of purchase intention. The low concentrations of liquid smoke solutions in this study did not affect the chemical properties of the treated steak samples in terms of moisture content, fat content and pH value.

An accurate characterization of the fine molecular structure of starch in terms of the chain length distribution (CLD) of amylopectin requires complete dispersion of the starch in a solvent, either buffer or water and the non-interference of this on the subsequent enzymatic debranching of starch with isoamylase (pretreatments before determining the CLD). In this study, the HYLON V and HYLON VII starches (commercial high-amylose corn starches) were selected, since high-amylose starches typically present difficulties in their dispersion and, therefore, the study of their fine structure can commonly present errors. The goal of this research was to study two water dispersion treatments (1. boiling water for 1 h and 2. autoclaving at 120 °C and 15 Psi for 15 min) to achieve a fast and reliable method of the fine structure of two high-amylose corn starches using high-performance size exclusion chromatography coupled with a refractive index detector (HPSEC-RID) and high-performance anion-exchange chromatography coupled a pulsed amperometric detector (HPAEC-PAD). The HPSEC-RID chromatograms of both starches showed better resolution using autoclaving than boiling water treatment. The two starches tested had higher amylose and degree of polymerization (DP) values utilizing the autoclaving than the boiling water treatment. However, no appreciable differences were observed in the CLD values employing HPAEC-PAD for either of the two water dispersion treatments. Lastly, the water dispersion treatment by autoclaving before enzymatic debranching is recommended to obtain a more accurate quantification of the amylose content of high-amylose starches.

Ensuring accurate classification of rice as either cooked or dry is vital for food safety, as improperly stored or cooked rice contain harmful bacteria, emphasizing the importance of maintaining and monitoring food safety standards. In the field of image analysis and food classification, classifying dry and cooked rice samples using photographs is an interesting but difficult task. The main challenge stems from the minute visual variations between cooked and dry rice, which has not always displayed distinct traits that are easily observable by machines. Hence, various machine learning algorithms were implemented to effectively mitigate this issue. However, the existing works have not analysed the physicochemical characteristics due to non-destructive type of experimentation method with image processing. To overcome this issue, this work develops the Classification and Regression Tree (CART) of Decision Tree Learning method for classifying the rice grain samples as dry or cooked based on the physicochemical characteristics such as morphological, texture and color features, which in turn gain an exhaustive facts of rice quality in diverse state. Initially, the images are captured, pre-processed and the features are extracted. From the extracted features, the rice samples are classified as dry and cooked using DT and the results are compared with the existing algorithms like K-Nearest Neighbour (KNN) and Support Vector Machine (SVM). The comparative analysis of these classification algorithms infers the outperformance of the DT learning model under morphological, texture and color features in terms of accuracy, error, precision, recall and F-score.

Capparis masaikai Lévl is a Chinese native plant that ripe seeds are often used as a traditional Chinese medicine for their heat antidotes properties. The locals like to chew the seeds for their distinctive flavor “sweet water taste”. In this study, enzymatic hydrolysis, gel filtration chromatography, and reversed-phase high-performance liquid chromatography were used to extract, isolate and purify flavor peptides from the seed kernels of Capparis masaikai Lévl. Nano-LC−MS/MS was used to identify 219 peptides in total. Five new bitter peptides (HIGP, FHP, CFR, LYR and SFR) were screened by molecular docking. The results of molecular docking indicated that hydrogen bonds and hydrophobic bonds played essential roles in the binding of the five bitter peptides to T1R2-T1R3, T2R1 and T2R34. Phe75 and Glu74 on T2R1 and Arg373 on T1R2-T1R3 might be the critical amino acids in the binding site. The taste properties of the synthesized peptides were confirmed by sensory evaluation, and it was found that five peptides exhibited a specific sweetness inhibition. Not only do these results shed light on the interaction between flavor peptides and taste receptors, but they also help explain the “sweet water taste” of the seed kernels of Capparis masaikai Lévl. The results of this study help to explore the potential of flavor peptides in an enzymatic hydrolysate of Capparis masaikai Lévl seed kernels and broaden the diversity of flavor sources for the “sweet water taste”.

Despite the popular claim that broths are a good source of essential elements, few studies have been devoted to clarifying this narrative. In fact, there is growing concern about the risk of ingesting toxic elements. This study focused on assessing the content of important elements (Ca, Cd, Cu, Fe, K, Mg, Na, and Pb) in various types of broths (beef, fish, poultry, pork, and vegetable). The samples (n = 30) included broths of different origins, including laboratory-prepared broths and broths prepared by professional cooks from Czech school canteens. The broths were evaluated as potential sources of essential elements in relation to their reference daily intake, as well as their potential toxicity risk in relation to Cd and Pb. Although significant variability was observed in the contents of the investigated elements, the results generally contradicted the popular narrative that broths are a good source of Ca, Cu, Fe, and Mg, as their contents did not achieve even 5% of the recommended daily intake. The amount of Ca in the broths was minimal even compared to the amount in tap water. The consumption of broths poses minimal risk regarding the presence of Cd and Pb.

Graphic abstract