Volume 22, No. 2 (2021)
Articles
INTERNAL OR EXTERNAL STANDARD TECHNIQUES FOR QUANTIFICATION OF FREE FATTY ACIDS (FFAs) IN RAW MILK AND KEFIR SAMPLES
AHMET DURSUN, ZEHRA GÜLER(*)
Free fatty acids (FFAs) can be analyzed by chromatographic methods as both qualitatively and quantitatively. The concentration of FFAs can be estimated by using internal or external standard techniques. The object of this study was to determine the recovery and repeatability of individual FFA (C2-C18:1) in milk and kefir, using internal or external standard (calibration curve). The FFAs adsorbed on aluminum oxide from samples are desorbed in isopropyl alcohol containing formic acid, which are analyzed using a gas chromatography-mass spectrometry (GC-MS) coupled with capillary column. The RSD of FFAs ranged from 2.77 % to 5.82 % for milk and from 1.02 % to 6.82 % for kefir. The recoveries of FFAs ranged from 82 % to 109.9 % and from 83.6 % to 109.3 %, respectively. The lowest recovery was obtained for hexadecanoic acid (82 %) in milk by the calculation relative to internal standard using relative correction factor. No significant differences in the concentrations of individual FFA were observed between internal and external standard techniques for milk but hexadecanoic and octadecenoic acids in kefir were higher at calculation by external standard compared to internal. In conclusion, the individual FFA showed a good repeatability in both kefir and milk. The high ethanol and acidity contents of kefir samples did not show a blocking effect on the alumina sorbent for isolation or releasing of FFAs.
EXTRACTION OF NIGELLA SATIVA SEEDS AT A PILOT SCALE AND THEIR EFFECTS ON THE FORMATION OF PSEUDOMONAS AERUGINOSA BIOFILMS
AMEL DIDI(*), MOHAMED AMINE DIDI
The extraction of vegetable oils from aromatic and medicinal plants has been the subject of research in several recent studies. Because of their richness in secondary metabolisms which are part of the manufacture of drugs, food supplements and cosmetic products. We are interested in discontinuous solid-liquid extraction of seeds of Nigella sativa at a pilot scale. Biological and physicochemical analysis was carried out on the extracts of these seeds, in order to valuate them. The results have shown that the extracts of Nigella sativa seeds are very rich in fatty acids and polyphenols in addition to the presence of other nutrients such as vitamins, amino acids and free quinones which have shown potential in phytotherapy. The extracts of the plant prevents the formation of Pseudomonas Aeruginosa biofilms. This study has given very promising results with regard to the efficiency of the extracts on free radicals and bacterial strains.
OPTIMIZATION OF TECHNOLOGICAL PARAMETERS FOR BIOTECHNOLOGICAL PRODUCTION OF FEED ADDITIVE BASED ON MICROBIOTA OF “TIBETAN KEFIR GRAINS”
OLENA VICHKO(1*), OLGA SHVED(2), MYKOLA KUKHTYN(1), ROMANNA PETRINA(2), ANDRIY МYLYANYCH(2), MARIIA BABII(1), VOLODYMYR NOVIKOV(2)
Biochemical and microbiological changes in processes of fermentation and storage of fermented milk product prepared using Tibetan kefir grains were studied. Principal stages for the production of feed additive were depicted in biotechnological and technological schemes with equipment. Technological parameters, conditions of cultivation and fermentation were selected to manufacture product in industrial scale.
PHYSICOCHEMICAL PROPERTIES EVALUATION OF MARINATED LAMB MEAT FROM DIFFERENT PRODUCTION SYSTEMS
SARWAR A.K.M. INAM(1), MD SUZAUDDULA(1,2*)
The objective of this study was to standardize two marination recipes and to determine any significant difference between intensively and extensively produced fresh and marinated lamb meat (Corriedale breed) through checking different quality parameters. One water-based and one oil-based marinade were standardized out of 14 marinades through sensory evaluation. Different physicochemical parameters including pH, color, volume loss, weight loss, tenderness, water holding capacity, moisture and fat content have been checked. Triangle test and ranking test were done to find out the best marinated samples. pH of marinated samples was significantly lower than fresh samples (P < 0.05). Marinated samples showed significantly higher lightness (L*) and yellowness (b*) but the lower value at redness (a*) comparing to fresh samples. All extensive samples and oil-based marinated sample exhibited significantly higher volume loss. Intensive samples were the tenderest while fresh and extensive samples appeared with higher water holding capacity. Intensive samples had the lowest and fresh samples had the highest moisture significantly (P < 0.05). Triangle test showed a significant difference in P value, 0.20 for water-based marinated sample and 0.05 for oil-based marinated samples. Extensive oil-based marinated samples had the highest ranking (α = 0.01) among other samples.
COMPARATIVE ANALYSIS OF THE LIPID CLASSES, FATTY ACID AND PHOSPHOLIPID PROFILES OF THREE SPECIES OF CITRUS FRUITS
AYOMADEWA M. OLATUNYA(1*), ABIMBOLA K. AJAJA(2), EMMANUEL T. AKINTAYO(1)
The oils extracted from the seeds of three species of citrus fruits were analyzed for their lipid classes, fatty acid composition, phospholipid profile and physicochemical properties. The seed oils were extracted using Soxhlet extraction method and the contents were analyzed using gas chromatographic techniques. The seed oils were rich in neutral lipids with lime seed oil having the highest percentage of 89.7 % and tangerine seed oil the lowest percentage of 84.83 %. The seed oils also showed the presence of glycolipids with values ranging from 6.95 - 8.90 %. The oils have high amount of total saturated and polyunsaturated fatty acid with values ranging between 35.8 - 40.3 % and 41.7 - 48.8 % respectively. The total phospholipid content was between 462 - 565 mg/100 g with very high concentration of phosphatidylinositol and phosphatidylcholine detected in the oil samples. The oils had very high percentage oil yield and saponification value. The iodine value of the oilseeds ranged between 102.3 - 135.5 I2 g/100 g with lime oil having the highest value. The results showed that the oils have high amount of essential fatty acids and phospholipids which are major components needed for the development and growth of some vital organs in the body system. The chemical and physical properties of the citrus oils also showed that the oils will have good application in various industries like food, soap, cosmetics and medicine.
INFLUENCE OF DIFFERENT VINE ROOTSTOCKS ON THE VOLATILE COMPOSITION OF RED WINES FROM KAYLASHKI RUBIN GRAPEVINE VARIETY
DIMITAR R. DIMITROV(*), ANATOLI M. ILIEV
In order to determine the effect of some rootstocks on the volatile composition of red wines from three harvests (2017, 2018 and 2019) of the grafted interspecific hybrid variety Kaylashki Rubin a gas chromatographic (GC-FID) study was performed. The highest total content of volatile compounds was found in wines from vintage 2017. Acetaldehyde (basic aldehyde) levels were detected in the variants of all three vintages, in concentrations indicating a properly conducted fermentation process and followed sulphitation procedures. In the 2018 and 2019 harvests, it was found that wines obtained from Kaylashki Rubin variety grafted on rootstocks 110 R (2018) and 44-53 M (2019) shown a higher final content of higher alcohols compared to the control. The main representatives of the fraction of higher alcohols identified in wines were 2-methyl-1-butanol, 3-methyl-1-butanol, 1-butanol, 1-hexanol, 4-methyl-2-pentanol, 1-propanol and 2-butanol. The best results for total ester content were found in the wines from the 2019 harvest. In them, the wines of the Kaylashki Rubin variety grafted on the 44-53 M and 110 R rootstocks shown a higher ester content than the control. The basic ester was ethyl acetate. The main representative of the terpene fraction was geraniol. The wines from the 2017 and 2019 harvests at the Fercal rootstock shown a tendency of a higher total terpene concentration compared to the control. In all tested variants, the typical for red wines methyl alcohol concentrations was detected.
SPECTROPHOTOMETRIC DETERMINATION OF POLYPHENOLIC AND PROTEIN CONTENT OF YOUNG WHITE WINES IN THE MOLDOVA AREA
ANDREEA HORTOLOMEU(1), IURIE SCUTARU(2), ALEXANDRA ARSENI(2), RODICA STURZA(2*), ILEANA DENISA NISTOR(1*)
In this paper, the processes of protein stability were treated in order to identify the level of protein substances as well as the polyphenolic compounds in white wines. For an optimal determination of the oxidation degree, respectively of the protein stability, a sample of 6 types of white wine from different grape varieties was chosen for analysis. For the heat treatment of protein stability has not yet materialized and published a working protocol in the literature, because many researchers in the field of vinification use different time intervals and temperature. In this paper, the method of thermal stability of proteins was used in two different working environments, respecting the same temperature and time: in the water bath and thermostat. By this method can be deduced the optimal amount of stabilizing agent for the removal of unstable proteins at high temperatures, being less affected by the presence of other polyphenolic compounds, metal cations and the pH of wine. The polyphenolic oxidation method was used to determine the degree of oxidability of the wines.
ANTIOXIDANT ACTIVITY DUAL METHODS OF DIFFERENT POLARITY EXTRACTS OF STEM OF SOLANUM NIGRUM L. GROWING IN ALGERIA
IMANE GUEDIRI(1,2*), CHERIFA BOUBEKRI(2), OUANISSA SMARA(1)
The purpose of this study is to evaluate the antioxidants properties and phenolic and flavonoid contents of Solanum nigrum L. growing in El-Oued region (south east of Algeria). The different polarity extracts chloroform (CHCl3), ethyl acetate (AcOEt) and n-butanol (n-BuOH) have been prepared from the aqueous ethanol extract of the stem. The antioxidant activity of extracts was determined by DPPH (2, 2-diphenyl-1-picrylhydrazyl), FRAP (Ferric ion reducing antioxidant power) assays. The results showed that CHCl3 extract has the highest level of polyphenol (66.427 ± 0.001 mg gallic acid / g) while, the AcOEt extract has the highest level of flavonoid content (26.450 ± 0.079 mg rutin equivalents / g). In addition, the highest IC50 of DPPH scavenging activity has exhibited the most potent antioxidant capacity assay of CHCl3 (0.231 mg∙mL-1) compared to the n-BuOH and AcOEt extracts. Furthermore, the highest value of FRAP for AcOEt extract was 458.291 ± 0.005. In this study, it has been noted that the potency of the antioxidant activity of DPPH may be identified through different levels of polyphenol. However, the value of FRAP has a relation to the value of flavonoid.
SENSORY AND PHYSICOCHEMICAL EVALUATION OF SOME VARIETIES OF ROMANIAN ARTISANAL MEAD
ELENA-MIRELA SUCEVEANU, IRINA-CLAUDIA ALEXA(*)
Mead is a honey-based alcoholic beverage with 8 - 18 % alcohol content. Also named honey wine, mead is not so well known among Romanian consumers, even if it is considered among the oldest fermented beverages in the world. It is traditionally produced at home and/or in small meaderies, but still it is difficult to find it commercially. Different varieties of mead can be distinguished based on honey types, honey/water ratio, addition of spices and/or fruits, and the method of preparation, etc. The present study was carried out in order to explore the Romanian consumers’ acceptability regarding the artisanal meads obtained using different types of honey from local producers (linden, multifloral, raspberry, wild forest, and acacia). It is well-known that the type of honey plays a significant role in the sensorial evaluation of mead. For this purpose, six samples of mead were prepared in the laboratory. The sensory characteristics, such as aspect, flavor, color, and taste were analyzed. The results revealed that the sample obtained from acacia honey using elderflower as additional ingredient is better accepted by the Romanian consumers than other types of mead.
IPS INFESTATION – A GLOBAL PROBLEM FOR CONIFEROUS IN THE FACE OF CLIMATE CHANGE
SIMONA ANDREI(1*), IRINA-LOREDANA IFRIM(2*)
Bark beetle infestation (Coleoptera: Curculionidae, Scolytinae) is a relevant issue for forestry sector at global scale. In Europe, the average wood lost because infestations was approximately 2.9 million m3/year in the last half of the twentieth century. In present, at a global scale, insects affect 30 million hectares of forest annually. The intensity of the bark beetle attack increases in temperate forests worldwide, in Europe, Asia, in southern parts of North America and in the north of the continent. In Alaska, during the period 1990-2000, spruce mortality was spread over an area of 1,19 million hectares. From 1990 to 2000, in Tatra Mountains, in Poland and Slovak Republic (Central Europe), more than 118,000 m3 of trees were damaged by Ips typographus infestation. Although it is the most important agent of tree mortality, bark beetle is considered a secondary pest because it has favorable conditions for development only in damaged trees. Climate warming and drought conditions have led to an unprecedented intensity of infestation. The spatial and temporal dynamics of bark beetle population outbreaks varies according to host species and insect aggressiveness. In this study, 112 articles were analyzed to discover the conditions favoring outbreaks and the severity of damage caused by bark beetle infestations.