Wasabia koreana Nakai: A Preliminary Study on Nutrients and Chemical Compounds That May Impact Sensory Properties.

In this study, the nutritional, functional, and chemical measurements of sensory attributes of different parts of wasabi, namely, leaf, petiole, and rhizome, were investigated. Proximate composition analysis showed the presence of high amounts of carbohydrates in the rhizome and amino acid composition analysis confirmed high proportions of glutamic acid and aspartic acid in all three parts. While proximate composition showed low lipid content in wasabi, ω-3 fatty acids accounted for a high proportion (>44%) of the total lipids. Wasabi leaves had high vitamin C and total phenolic contents, and thus demonstrated antioxidant capacity. Allyl isothiocyanate, which gives wasabi its characteristic pungent taste, was identified by gas chromatography/mass spectrometry and an electronic nose. On an electronic tongue, wasabi leaves showed compounds associated with sourness and saltiness while the petiole had high content of compounds associated with sweetness and bitterness. This study provides basic data for the utilization of wasabi parts as food materials based on their nutritional, functional, and chemical measure of sensory attributes.

Polycyclic aromatic hydrocarbons in beverage and dairy products in South Korea: a risk characterization using the total diet study.

Polycyclic aromatic hydrocarbons (PAHs) were analyzed using gas chromatography-mass spectrometry in 115 dairy products and beverages, including alcoholic, grain, carbonated, and functional drinks; fruit and vegetable juices; coffee; and tea, purchased from 10 local city markets in South Korea. The sample groups were divided into non-fatty and fatty groups, pretreated with the ultrasound-assisted extraction method and saponification method, respectively. The limit of detection, limit of quantification, and accuracy were 0.038-0.185 µg/kg, 0.114-0.560 µg/kg, and 87.64-112.25%, respectively. The measurement uncertainty was ≤ 6.38% for eight PAHs (PAH8). PAH8 was detected in 41 of the 115 samples, ranging from 0.041 to 7.793 µg/kg. The risk assessment revealed that the margin of exposure for PAH8 ranged from 3.60 × 104 to 7.84 × 1011 in the mean intake groups and from 3.60 × 104 to 5.33 × 1011 in the P97.5 intake groups. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-021-00927-7.

Reduction of the polycyclic aromatic hydrocarbon levels in dried red peppers (Capsicum annuum L.) using heat pump-assisted drying.

Polycyclic aromatic hydrocarbons (PAHs) are primarily produced during the incomplete combustion of organic matter. PAHs are suspected endocrine disruptors and possible carcinogenic materials. The major sources of human exposure to PAHs are inhaled fumes and food. The aim of this study was to provide an alternative drying method to mitigate PAH formation in dried red peppers. We prepared dried red pepper samples using air-drying and heat pump-assisted drying methods, and measured the concentrations of four PAHs (PAH4), benzo[a] anthracene (B[a]A), chrysene (CHR), benzo[b]fluoranthene (B[b]F), and benzo[a]pyrene (B[a]P), in the resulting pepper samples. The PAH concentrations ranged from 3.61 to 18.0 µg/kg and from 2.22 to 8.35 µg/kg in the air-dried and heat pump-dried pepper samples, respectively. Overall, the results have shown that dried peppers contain PAH4, that the drying conditions for these contaminants should be optimized for mitigating the PAH formation in dried red peppers.

Comprehensive changes in volatile/nonvolatile compounds and flavor and physicochemical characteristics in Angelica gigas Nakai roots by thermal processing.

This study investigated the changes of physicochemical and flavor characteristics of Angelica gigas Nakai roots during roasting. Glutamic acid and arginine were higher in constituent amino acids. In the taste value, glutamic acid was highest in constituent and free amino acids. Total phenol contents were highest in 0 min and lowest in 3 min. Hundred twenty-six volatile compounds were detected by GC/MS during roasting. α-pinene, eudesmol, nonane, and limonene were detected as major volatile compounds. For antioxidant ability, 1,1-diphenyl-2-picrylhydrazyl did not change during roasting, and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid showed the highest value in 3 min. Browning intensity showed a slight decrease over time. In Electronic nose, fragrance increased by roasting, and strength, NH3 , and H2 S decreased significantly. In Electronic tongue, sweetness, bitterness, and umami taste increased by roasting, and this was related to amino acid composition. The results provide basic data on the physicochemical and flavor characteristics of A. gigas Nakai according to the roasting process. PRACTICAL APPLICATIONS: Angelica gigas Nakai has been known as a medicinal herb in Asian countries and usually consumed in powder, tea, and snacks. In order to produce the powder, tea, or snacks with A. gigas Nakai, thermal treatment is an essential and critical process. Despite that existing studies reported many physiological benefits and functional properties of A. gigas Nakai, studies have rarely discovered how the nutritional properties and volatile compounds of A. gigas Nakai alter when it undergoes thermal treatment. Therefore, this study will be utilized as basic data to optimize the thermal processing conditions (e.g., roasting time) for the production of food products with A. gigas Nakai such as tea and snacks. This study further provides objective chemical measures of sensory profiles of A. gigas Nakai using electronic tongue and electronic nose during the thermal processing.

Chemical Characterization and Oxidative Stability of Medium- and Long-Chain Fatty Acid Profiles in Tree-Borne Seed Oils.

This study was undertaken to evaluate chemical characteristics and oxidative stability of tree-borne seed oils. A total of 15 different fatty acids were identified in six tree-borne seed oils, which included seven types of saturated fatty acids, four types of monounsaturated fatty acids, and four types of polyunsaturated fatty acids. Japanese camphor tree (JCT) had a high content of medium-chain fatty acids (97.94 ± 0.04%), in which fatty acid composition was distinct from those of the other five plant seed oils. Overall, contents of tocopherols, a type of fat-soluble vitamin, ranged between 3.82 ± 0.04 mg/100 g and 101.98 ± 1.34 mg/100 g, respectively. Phytosterol contents ranged from 117.77 ± 1.32 mg/100 g to 479.45 ± 4.27 mg/100 g, respectively. Of all tree-borne seed oils, ß-sitosterol was the phytosterol at the highest concentration. Contents of unsaponifiables were between 0.13 ± 0.08 and 2.01 ± 0.02, and values of acid, peroxide, and p-anisidine were between 0.79 ± 0.01 and 38.94 ± 0.24 mg KOH/g, 3.53 ± 0.21 and 127.67 ± 1.79 meq/kg, and 2.07 ± 0.51 and 9.67 ± 0.25, respectively. Oxidative stability of tree-borne seed oils was assessed through measurement of oxidation-induction periods. These results should serve as a foundation to identify the potential of tree-borne seed oils in industrial application as well as in providing fundamental data.

IDH2 Deficiency Aggravates Fructose-Induced NAFLD by Modulating Hepatic Fatty Acid Metabolism and Activating Inflammatory Signaling in Female Mice.

Fructose is a strong risk factor for non-alcoholic fatty liver disease (NAFLD), resulting from the disruption of redox systems by excessive reactive oxygen species production in the liver cells. Of note, recent epidemiological studies indicated that women are more prone to developing metabolic syndrome in response to fructose-sweetened beverages. Hence, we examined whether disruption of the redox system through a deletion of NADPH supplying mitochondrial enzyme, NADP⁺-dependent isocitrate dehydrogenase (IDH2), exacerbates fructose-induced NAFLD conditions in C57BL/6 female mice. Wild-type (WT) and IDH2 knockout (KO) mice were treated with either water or 34% fructose water over six weeks. NAFLD phenotypes and key proteins and mRNAs involved in the inflammatory pathway (e.g., NF-κB p65 and IL-1ß) were assessed. Hepatic lipid accumulation was significantly increased in IDH2 KO mice fed fructose compared to the WT counterpart. Neutrophil infiltration was observed only in IDH2 KO mice fed fructose. Furthermore, phosphorylation of NF-κB p65 and expression of IL-1ß was remarkably upregulated in IDH2 KO mice fed fructose, and expression of IκBα was decreased by fructose treatment in both WT and IDH2 KO groups. For the first time, we report our novel findings that IDH2 KO female mice may be more susceptible to fructose-induced NAFLD and the associated inflammatory response, suggesting a mechanistic role of IDH2 in metabolic diseases.