Electrophilic components from Xiaoheiyao (rhizomes of Inula nervosa Wall.) alleviate the production of heterocyclic aromatic amines via creatinine inhibition.

Xiaoheiyao is the rhizome of Inula nervosa Wall., a traditional spice and medicinal herb in China. In this study, the creatinine inhibitor from Xiaoheiyao extract and also the effects and mechanism on the production of heterocyclic aromatic amines (HAAs) were investigated. Xiaoheiyao extract inhibited the total contents of seven detected HAAs in grilled beef patties, particularly aminoimidazole-azaarenes (AIAs) in a dose-dependent manner, reaching a maximum inhibition rate of 62% for total HAAs and 73% for AIAs. The most effective subfraction of Xiaoheiyao extract (IER80) contained abundant potential creatinine inhibitors, as revealed by immobilized creatinine probe, HPLC and UPLC-MS/MS analyses. Moreover, electrophilic p-coumaric acid derivatives were discovered from IER80 by feature based molecular networking. p-Coumaric acid was demonstrated to inhibit the contents of total HAAs and AIAs in grilled beef patties and model system. Quantitative analyses of the precursor and intermediates of AIAs in model system revealed that p-coumaric acid mainly affected the generation of AIAs by inhibiting creatinine.

Flavor Components Comparison between the Neck Meat of Donkey, Swine, Bovine, and Sheep.

Donkey in China is well known for its draft purpose and transportation; however, donkey meat has attracted more and more consumers in recent years, yet it lacks sufficient information on its flavor components compared to other main meats. Therefore, in this study, volatile flavor compounds in neck meat of donkey, swine, bovine, and sheep were classified by electronic nose, then confirmed and quantified by gas chromatography-mass spectrometry. High-performance liquid chromatography (HPLC) and gas chromatography were used to quantify free fatty acid, amino acid, and flavor nucleotide. A total of 73 volatile compounds were identified, and aldehydes were identified as the characteristic flavor compounds in neck meat of donkey, bovine, swine and sheep in proportion of 76.39%, 46.62%, 31.64%, and 35.83%, respectively. Particularly, hexanal was the most abundant volatile flavor. Compared with other neck meat, much higher unsaturated free fatty acids were present in donkeys. Furthermore, neck meat of donkeys showed essential amino acid with highest content. Thus, special flavor and nutrition in donkey neck meat make it probably a candidate for consumers in other regions besides Asia.

Antioxidant capacity of hydrolyzed protein fractions obtained from an under-explored seed protein: Gingerbread plum (Neocarya macrophylla).

The antioxidant capacity of gingerbread plum kernel protein fraction (albumin, globulin and glutelin) hydrolysates (GPKH) was studied. Gingerbread plum kernel protein fractions were hydrolyzed through a combined action of two digestive enzymes (pespsin and trypsin). The hydrolyzed fractions were subjected to antioxidant test via several chemical assays such as: DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, hydroxyl radical-scavenging activity, reducing power and metal chelating activity. Total phenolic contents, amino acid composition and molecular weight distribution were also evaluated. The glutelin fraction hydrolysate showed the strongest antioxidative activity throughout the entire investigation: 79.09, 58.81, 52.08 % and 40.7 µg/mL GAE for DPPH, hydroxyl radical, chelating activity and total phenolics respectively. GPKH possess a molecular weight ranging from 300 to 4000 Da and also showed much more high reducing power than some common standards such as BHA and α-tocopherol indicating that, hydrolysates derived from gingerbread plum kernel protein could be a new antioxidants source.

Comparison of physicochemical and functional properties of flour and starch extract in different methods from Africa locust bean (Parkia biglobosa) seeds.

BACKGROUND: African locust bean tree is an important food tree for both human and livestock such as husks and pods. It plays a very vital role in the rural areas. The aim of this study was to evaluate some physicochemical, mineral characteristics and functional properties of flour and starch extract produced from Parkia biglobosa seeds, using different methods. MATERIALS AND METHODS: Three different methods were used for starch extraction in other to get the Starch yield (%),composition analysis for; moisture, protein, fat, ash and fiber contents of flour and starch extracts from Parkia biglobosa were determined on dry basis (db), by AACC method, color and PH value measurements was carried out using color flex spectrocolorimeter, and the official method of AOAC respectively. Pasting properties was determined and X-ray powder starch diffraction was used to examine the crystalline property of flour and starch extract. Gelatinization characteristics and in vitro starch digestibility were also determined, test results were processed using one-way analysis of variance (ANOVA). RESULTS: Flour showed higher (P < 0.05), moisture content, fat, carbohydrate, amylopectine, and protein content than starch, while amylose content of this starch was higher (P<0.05). Phosphorus, sodium, magnesium, and potassium minerals content were higher in flour than starch. Pasting properties, gelatinisation, color, pH values, water and oil absorption capacity content of the flour were found to be higher than that of starch. The pasting characteristics showed a decrease of viscosity, final viscosity, set back value, breakdown, and pasting temperature of flour when compared to that of starch. CONCLUSION: From our results, we speculate that flour from native Parkia biglobosa grown in Guinea under controlled environmental conditions could be considered as an ideal RS material, whereas the extract Parkia starch could be an ideal SDS material. Therefore, these may offer an interesting alternative for food developers, depending on their characteristics and functional properties.

Functionality and antioxidant properties of tilapia (Oreochromis niloticus) as influenced by the degree of hydrolysis.

Freeze dried protein powders (Fresh minced meat, FMM and Hot water dip, HWD) from tilapia (Oreochromis niloticus) were hydrolyzed by Alcalase 2.4 L (Alc), Flavourzyme (Flav) and Neutrase (Neut), and investigated for antioxidant activity and their functional properties. FMM and HWD hydrolysed by Alc, exhibiting superior antioxidant activity, had estimated degrees of hydrolysis (DH) of 23.40% and 25.43%, respectively. The maximum values of the 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 3-(2-pyridyl) 5,6-bis(4-phenyl-sulphonic acid)-1,2,4-triazine (ferrozine), radical scavenging activities and metal chelating properties were 86.67%, 91.27% and 82.57%, and 84.67%, 92.60% and 78.00% for FMM and HWD, respectively, with a significant difference (P < 0.05) between the samples. Essential amino acids were above the amounts recommended by the Food and Agricultural Organization/World Health Organization (FAO/WHO/UNU) for humans. Lower molecular weight sizes <3,000 Da were more predominant in FMM and HWD hydrolysed by Alc, while in hydrolysed by Flav and Neut they were >8,000 Da. At pH 2, FMM and HWD hydrolysates have varying solubilities above 85% (Alc FMM; 91.33%, Flav FMM; 79.5%, Neut FMM; 83.8% and Alc HWD; 90.45%, Flav HWD; 83.5%, and Neut HWD; 85.8%). They have 'U' shaped solubility curves, water holding capacity was in the range of 2.77 and 1.77 mL/g, while oil holding capacity ranged between 3.13 and 2.23 mL/g. FMM and HWD have the highest bulk density of 0.53 and 0.53 for Neutrase and Alcalase 2.4 L, respectively. Foam capacity and stability ranged from 125.5 to 61.4, 138.5 to 45.2, 130.0 to 62.5, and 124.5 to 55.0, 137.5 to 53.3, 129.6 to 62.7 for FMM and HWD hydrolyzed with Alcalase 2.4 L, Flavourzyme and Neutrase, respectively. Tilapia fish protein hydrolysates are thus potential functional food ingredients.