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Effects of HCl, H 2 SO 4 , HNO 3 , citric acid, and acetic acid on the yield, structure, and emulsifying properties of potato pectins were investigated. Results showed that the highest yield (14.34%) was obtained using citric acid, followed by HNO 3 (9.83%), HCl (9.72%), H 2 SO 4 (8.38%), and acetic acid (4.08%). The degrees of methylation (37.45%) and acetylation (15.38%), protein content (6.97%), and molecular weight (3.207 × 10 5  g/mol) were the highest for pectin extracted using acetic acid, and (galactose + arabinose)/rhamnose was 33.34, indicating that it had a highly branched rhamnogalacturonan I domain. Fourier transform infrared spectroscopy showed a specific absorbance peak at 1064 cm −1 , which corresponds to the acetyl groups in potato pectins. SEM showed that all potato pectins are morphologically different. The emulsifying activity (EA, 44.97%–47.71%) and emulsion stability (ES, 36.54%–46.00%) of the pectins were influenced by acid types, and were higher than those of commercial citrus and apple pectin. [ABSTRACT FROM AUTHOR]

This study investigated the effects of alkaline pretreatments and acid extraction conditions on the production of acid-soluble collagen (ASC) from grass carp skin. For alkaline pretreatment, 0.05 and 0.1 M NaOH removed non-collagenous proteins without significant loss of ASC at 4, 10, 15 and 20 °C; while 0.2 and 0.5 M NaOH caused significant loss of ASC, and 0.5 M NaOH caused structural modification of ASC at 15 and 20 °C. For acid extraction at 4, 10, 15 and 20 °C, ASC was partly extracted by 0.1 and 0.2 M acetic acid, while 0.5 and 1.0 M acetic acid resulted in almost complete extraction. The processing conditions involving 0.05–0.1 M NaOH for pretreatment, 0.5 M acetic acid for extraction and 4–20 °C for both pretreatment and extraction, produced ASC with the structural integrity being well maintained and hence were recommended to prepare ASC from grass carp skin in practical application. [ABSTRACT FROM AUTHOR]

• Acid types had a significant effect on the yield of wampee fruit peel pectic polysaccharide (WFPP) • Sugar composition and branches of WFPPs could be modulated by acid types. • Surface morphology and main structure of WFPPs was little changed by acid types. • The emulsifying properties of WFPPs were higher than commercial citrus pectin. • WFPP extracted by oxalic, acetic, or hydrochloric acid had better functional properties. Effects of different extraction acids on physicochemical, structural, and functional properties of wampee fruit peel pectin (WFPP) were comparatively investigated. The hydrochloric acid extracted WFPP (HEP) exhibited the highest degrees of methylation (67.79%) and acetylation (86.29%) coupling with abundant monosaccharides and rhamnogalacturonan branches, but lowest molecular weight (5.58 × 105 Da). The results of SEM, X-ray diffraction, and Fourier transform infrared spectroscopy analyses showed that acid types had little effect on the surface morphology of WFPP. However, compared to commercial citrus pectin (CCP), several specific absorbance peaks (1539, 1019, 920 cm−1) were found in WFPPs, which corresponds to aromatic skeletal stretching, pyranose, and d -glucopyranosyl, respectively. Moreover, the rheological behavior revealed that WFPP solution was pseudoplastic fluid and affected by acid types. And the WFPPs exhibited higher emulsifying activity and emulsion stability than CCP. All these WFPPs presented well antioxidant activity and promoting probiotics ability, especially for HEP. [ABSTRACT FROM AUTHOR]

Abstract: Trace elemental analysis, besides its ability to determine stable isotopes ratios, represents a possible complementary tool useful to differentiate wines based on their regional origins. Wines and their provenance soils from two major wine producing areas in Southeast Romania (‘Valea Calugareasca’ and ‘Murfatlar’), and also wine from the region of Moldova (Eastern Romania) were analyzed by inductively coupled plasma mass spectrometry (ICP-MS), and statistical data of elemental composition was used to differentiate these wines according to grape type and geographical origin. Moreover, this study gathers relevant elemental trace composition of wines produced in most important Romanian vineyards, thus offering a useful wine differentiation tool by their production district. The results show that the differentiation of Romanian wines according to their provenance is based on the following main elements: Ni, Ag, Cr, Sr, Zn, and Cu for Valea Calugareasca, Rb, Zn, and Mn for Murfatlar, and Pb, Co, and V for Moldova. [Copyright &y& Elsevier]

Abstract: Linamarin, a cyanogenic glycoside in cassava (Manihot esculenta Crantz cv. KU-50) root cortex and parenchyma was extracted with different acids (HCl, H2SO4, H3PO4 or CH3COOH) and detected by high performance liquid chromatography (HPLC). The highest linamarin was found in both tissues extracted with H2SO4. However, the concentration of linamarin in the extract of the root cortex was higher than that of the root parenchyma. Linamarin in crude extract of the root cortex using 0.25 M H2SO4 was purified by the second step HPLC with the yield of 91.54%. These extraction, detection and purification methods were useful to improve the purity of linamarin from cassava, especially the root cortex. [Copyright &y& Elsevier]