Dynamic correlations between major enzymatic activities, physicochemical properties and targeted volatile compounds in naturally fermented plain sufu during production

This study aimed to measure the effect of roasting time on physicochemical properties and volatile compounds of unfermented cocoa liquor roasted with an oil bath method. Physicochemical properties (pH, temperature, and color), flavor, and volatile compounds were analyzed. The results showed that the longer the roasting time the higher the unfermented cocoa liquor’s temperature, °Hue, and ΔE value, but lower pH and L value. There were 126 volatile compounds obtained by various roasting time, identified as pyrazines (12), aldehydes (16), esters (1), alcohols (31), acids (15), hydrocarbons (11), ketones (19), and others (21). At 15, 20, and 25 minutes of roasting time, 69, 74, and 67 volatile compounds, respectively, were identified. Volatile compounds’ profiles were indicated to be strongly influenced by roasting time. The largest area and highest number of compounds, such as pyrazines and aldehydes, were obtained at 20 minutes, which was also the only time the esters were identified. As well as the time showed a very strong flavor described by panelists.

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Soil CO2 and CH4 concentration dynamics and their relationships with soil physicochemical properties, soil enzyme activity, and root biomass under shallow groundwater level

10.22541/au.160562653.39881928/v1 ◽

2020 ◽

Author(s):

Wenchao Zhang ◽

Xinguo Zhou ◽

Jianqiang Zhu ◽

Fahu Li

Keyword(s):

Winter Wheat ◽

Physicochemical Properties ◽

Root Biomass ◽

Shallow Groundwater ◽

Enzymatic Activities ◽

Groundwater Depth ◽

Soil Co2 ◽

Total N ◽

Groundwater Levels ◽

Ch4 Concentration

Soil CO2 and CH4 concentrations are crucial determinants of crop physiology and soil environment. This study aimed to investigate the dynamics of soil CO2 and CH4 concentrations and their correlations with soil nutrient content, enzymatic activities and root biomass at shallow groundwater levels. Lysimeter experiments were conducted at five groundwater depths (20, 40, 50, 60, and 80 cm) and three fertilizer application rates (low, 75%; normal, 100%; high, 125%). Soil CO2 and CH4 concentrations, physicochemical properties, and enzymatic activities were determined in the three growth stages of winter wheat crop, and plant biomass was measured post-harvest. Groundwater depth significantly (P ≤ 0.001) affected CO2 and CH4 concentrations and root parameters, and their critical values appeared at the groundwater depth of 50–60 cm. Soil water content presented quadratic function relation with CO2 concentration, and exhibited the linear correlation with CH4 concentration. As an aerobic respiration product, soil CO2 concentration showed significant positive correlations with organic matter and total N levels, urease, phosphatase and sucrase activities, and root biomass in winter wheat. Soil CH4 concentration depending on anaerobic microbial activity showed significant correlations with soil nutrients, such as soil organic matter, total N, and available K. Fertilization significantly impacted root parameters (P ≤ 0.001) and shoot biomass (P ≤ 0.05) instead of CO2 and CH4 concentrations. In contrast, groundwater depth emerged as a crucial factor as it affected soil physicochemical properties, soil enzymatic activities, root respiration, and winter wheat growth at shallow groundwater levels.

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Physicochemical Properties, Fatty Acid Composition, Volatile Compounds of Blueberries, Cranberries, Raspberries, and Cuckooflower Seeds Obtained Using Sonication Method

Molecules ◽

10.3390/molecules26247446 ◽

2021 ◽

Vol 26 (24) ◽

pp. 7446

Author(s):

Dorota Bederska-Łojewska ◽

Marek Pieszka ◽

Aleksandra Marzec ◽

Magdalena Rudzińska ◽

Anna Grygier ◽

...

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Physicochemical Properties ◽

Volatile Compounds ◽

High Performance ◽

Essential Fatty Acids ◽

Monounsaturated Fatty Acids ◽

Rubus Idaeus ◽

Extraction Temperature ◽

Cardamine Pratensis

Every year, thousands of tons of fruit seeds are discarded as agro-industrial by-products around the world. Fruit seeds are an excellent source of oils, monounsaturated fatty acids, and n-6 and n-3 polyunsaturated essential fatty acids. This study aimed to develop a novel technology for extracting active substances from selected seeds that were obtained after pressing fruit juices. The proposed technology involved sonification with the use of ethyl alcohol at a low extraction temperature. Seeds of four species—blueberry (Vaccinium myrtillus L.), raspberry (Rubus idaeus), cranberry (Vaccinium macrocarpon), and cuckooflower (Cardamine pratensis)—were used for extraction. Following alcohol evaporation under nitrogen, the antioxidant activity, chemical composition, and volatile compounds of the obtained extracts were analyzed using chromatographic methods, including gas chromatography (GC)–mass spectrometry (MS) (GC–MS/MS), and high-performance liquid chromatography–MS. We analyzed physicochemical properties, fatty acid, and volatile compounds composition, sterol and tocochromanol content of blueberry, cranberry, raspberry, and cuckooflower seed oils obtained by sonication. This method is safe and effective, and allows for obtaining valuable oils from the seeds.

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Effects of an Extract from Olive Fruits on the Physicochemical Properties, Lipid Oxidation and Volatile Compounds of Beef Patties

Foods ◽

10.3390/foods9121728 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1728

Author(s):

Inmaculada Gómez ◽

Celia García-Varona ◽

María Curiel-Fernández ◽

Miriam Ortega-Heras

Keyword(s):

Physicochemical Properties ◽

Lipid Oxidation ◽

Volatile Compounds ◽

Modified Atmosphere Packaging ◽

Modified Atmosphere ◽

Beef Patties ◽

Microbiological Characteristics ◽

Red Color ◽

Volatile Organic ◽

Effective Antioxidant

The aim of this work was to evaluate the effect of an olive extract (OE) on the physicochemical and microbiological characteristics, lipid oxidation and volatile compounds of beef patties stored both aerobically and under modified atmosphere packaging for 15 days at 4 °C. The antioxidant and antimicrobial effects of the OE were compared to those of sulfite. Four formulations were elaborated according to the antioxidant and dose used: without antioxidant, C; 300 mg potassium metabisulfite/kg product, S; 150 mg OE/kg product, OE1; and 250 mg of OE/kg product, OE2. The parameters analyzed were pH, water activity, color, lipid oxidation (TBARS and volatile organic compounds: hexanal, 2-pentyl-furan, 1-pentanol, 2,3-octanedione and nonanal, 1-octen-2-ol) and total viable counts. The OE delayed the loss of the bright red color of the patties and reduced the lipid oxidation in both types of packaging compared to the control patty. Sulfite was the most effective antioxidant for inhibition of the total viable counts. An OE could be used as a natural antioxidant to delay the lipid oxidation of meat without negatively affecting its physicochemical properties.

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