Effect of the diet with commercial dry yeast (Saccharomyces cerevisiae) on organoleptic qualities, chemical and biological parameters of common carp (Cyprinus carpio L.)

N.M. Abdulrahman1*, I.H. Al-Refaiee2, H. Ali Mutter3

1College of veterinary medicine, University of Sulaimani, Sulaimaniya, Iraq
2Ministry of Agriculture, Al- Anbar province, Iraq
3College of Agriculture, University of Anbar, Al- Anbar province, Iraq

(Manuscript received 9 July 2018; accepted for publication 31 January 2019)

Abstract. The purpose of the present study was to evaluate the replacement of different levels of animal protein concentrate (APC) with a commercial dry yeast Saccharomyces cerevisiae in diets on common carp performance. The experiment was conducted in the fish laboratory of the Department of Animal Production, College of Agricultural Sciences, University of Sulaimani in Kurdistan region of Iraq for the period from 25.07.2015 to 15.10.2015. Starting with a period of acclimatization for 21 days, to test the efficiency of using commercial dry yeast S. cerevisiae as alternative protein source to APC used in the manufacturing of diets for common carp (Cyprinus carpio L.) by using 90 fish at weights ranged 22-42g divided into 15 groups distributed randomly on 15 plastic containers by five treatments with three replicates per each variant. The treatments contain different levels of APC and yeast S. cerevisiae as follows: first treatment (Control T1): 100% APC / 0.00% yeast S. cerevisiae; second treatment (T2): 75% APC / 25% yeast S. cerevisiae; third treatment (T3): 50% APC / 50% yeast S. cerevisiae; fourth treatment (T4): 25% APC / 75% yeast S. cerevisiae and fifth treatment (T5): 0.00% APC / 100% yeast S. cerevisiae. There was no significant difference observed in the value of biological indices for some physiological organs, spleen and Hepatic pancreases and also in the value of the condition factor (CF) between carps from different treatments. The results of the chemical composition of the fish flesh showed significant difference in the moisture of individuals from T4 as compared with these from T2 and T5, T2 was significantly increased in crude protein as compared with other treatments, T5 had significant differences in fat crude as compared with other treatments, T1 and T2 were significantly different in ash as compared with other treatments, T1 was significantly different in carbohydrates as compared with other treatments. The results showed no significant differences observed among experimental treatments in Panel test of tenderness, color, juiciness, flavor and overall acceptance for fish meat.

Colour and rehydration properties of bay leaves dried by convective and microwave methods

A. Polat, N. Izli

Department of Biosystems Engineering, Agriculture Faculty, Bursa Uludag University, Gorukle Campus, 16059 Nilüfer, Bursa, Turkey

(Manuscript received 26 July 2018; accepted for publication 30 November 2018)

Abstract. This study aims to evaluate the effect of the convective and microwave dying methods on the colour parameters (L*, a*, b*, C,  and ΔE) and rehydration ratio of bay leaves. Drying experiments were conducted using 350 and 460W of microwave powers and air temperatures of 50, 60 and 70C. Different microwave powers show significant effect on colour of dried bay leaves. Increasing microwave power, a* (redness/greenness),  (hue angle) and ΔE (total colour changes) values increased whereas L* (lightness), b* (yellowness/blueness) and C (Chroma) values decreased. For the convective drying, although there are changes in the values of the colour parameters (L*, a*, b*, C and ), there are no significant differences in the values of the total colour changes (ΔE) statistically (P>0.05). The effect of microwave power levels and air temperature on rehydration characteristics was determined. It was found that the rehydration ratio values decreased with an increasing temperature and increasing power levels. The highest rehydration ratio was recorded for the samples dried at 350W and the lowest ratio was seen in a sample dried at 70°C. Microwave drying can be a practical drying process, an alternative to convective drying for drying bay leaves.

Quantity and quality of wool yolk in Caucasian Merino rams

D. Pamukova1*, G. Staykova2, N. Stancheva2

1Department of Animal Husbandry- Ruminant Animals and Dairy Science, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria 2Agricultural Institute, 9700 Shumen, Bulgaria

(Manuscript received 2 September 2018; accepted for publication 5 November 2018)

Abstract. The aim of this study was to determine the quality and quantity of the wool yolk of the rams from Caucasian merino breed in order to improve their technological features. The analyses included seven rams at 2.5 years of age and eleven male lambs at the age of 18 months. Thirty-six individual wool samples from two parts of the body (side and thigh) were studied. The following wool parameters were investigated: percentage of the dirty areas of the wool (on the side and the thigh), fat amount, sweat amount, pH of sweat, laboratory wool yield, and color of greasy wool on the side. Percentage of the dirty areas of the wool by categories and topographic ranges varied from 30.79% to 41.52%, indicating that the wool yolk of Caucasian rams was of sufficient quantity and good quality. The percentage of the fats in wool yolk to the greasy wool was relatively high (23.25% in the male lambs at the age of 18 months and 25% in the rams) and had a negative impact on the wool yield. The ratio of fat/sweat was 1.91:1 in rams at 2.5 years of age and 1.44:1 in male lambs at the age of 18 months). The higher relative part of the fat compared to the sweat was an indicator of good protective properties of the wool yolk. That allowed to protect the technological properties of the wool.

Proximate composition, lipid quality and heavy metals content in the muscle of two carp species

A. Merdzhanova*, V. Panayotova, D.A. Dobreva, K. Peycheva

Department of Chemistry, Faculty of Pharmacy, Medical University, 9000 Varna, Bulgaria (Manuscript received 2 August 2018; accepted for publication 12 October 2018)

Abstract. The aim of the presented study was to characterize the quality of edible tissue of freshwater common carp (Cyprinus carpio) and bighead carp (Aristichthys nobilis), based on their proximate and lipid composition (lipid classes, fatty acid profile, fat soluble vitamins, carotenoids and cholesterol). Health risk assessment was evaluated based on the analysis of some toxic elements (As, Cd, Ni, Pb and total Hg). Proximate composition (moisture, crude protein and total lipid) was determined using standard procedures. Lipids were subsequently separated into neutral (NL) and polar lipids: Phospho- (PL) and Glycolipids (GL) by means of column and thin-layer chromatography. Lipid classes were derivatized into fatty acid methyl esters (FAMEs) which were analysed by gas chromatography–mass spectrometry (GC-MS). Vitamins A, D3 and E, beta-carotene, astaxanthin and cholesterol were analysed simultaneously using high performance liquid chromatography (HPLC). Heavy metals (As, Pb, Cd, Hg and Ni) were determined by optical emission spectrometry with inductively coupled plasma (ICP-OES) following a microwave digestion procedure. Protein content was higher in bighead carp (18.5%) and lower for common carp (15.5%), whereas lipid content showed opposite trend. Similarities in lipid classes distribution were observed for both species: NL>GL>PL. Neutral lipids constituted approximately 70% of TL in both species, as FAs profile was dominated by monounsaturated fatty acids (MUFA), whereas polyunsaturated FAs (PUFA) prevailed in polar fractions. Omega-3 PUFAs were higher in all lipid classes compared to omega-6 PUFAs. Cholesterol content was low (17-24 mg.100-1g ww). Astaxanthin was detected only in bighead carp, whereas beta-carotene, vitamin D3 and vitamin A showed similar concentrations in both samples. Vitamin E content was higher in bighead carp (10.4 mg.100 g-1 w.w.). Trace elements content was higher in bighead carp showing a maximum value of As (0.312 mg.kg-1 w.w). All determined toxic elements were found below the recommended value in carp muscle. The results of the present study confirmed the high quality and safety of common carp and bighead carp meat. These freshwater species are valuable sources of essential nutrients such as proteins, vitamin D3 and long chain omega-3 PUFAs. Together with the nutrients, the information for low concentrations of toxic elements makes them valuable components of a healthy human diet.

Effect of Аrtemisia annua L. extract on growth performance, biochemical blood parameters and meat quality of rainbow trout (Oncorhynchus mykiss W.), cultivated in recirculating system

  1. Koshinski*


Department of Biology and Aquaculture, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria


DOI: 10.15547/ast.2018.03.051

(Manuscript received 30 June 2018; accepted for publication 20 August 2018)


Abstract. Medicinal herbs can be used as feed additives to improve animal growth performance and to optimize physiological processes. The purpose of this study was to trace growth performance, meat quality and biochemical blood parameters (glucose, urea, creatinine, total protein, albumin, ASAT, ALAT, Ca, P, Mg, triglycerides, cholesterol) of rainbow trout (Oncorhynchus mykiss W.), fed with additive sweet wormwood (Аrtemisia annua L.) extract. In a recirculation system at the Aquaculture Base of the Faculty of Agriculture at Trakia University, a control group (no added) and an experimental (with added 204 mg.kg-1 of sweet wormwood extract) option were set, each of them with two replicates and mean initial weight of fish 13.32±3.07g and 13.37±2.76g, respectively. Forty specimens of rainbow trouts in good health condition were placed in each tank and cultivated for 60 days. At the end of the experiment average final weight, specific growth rates, feed conversion ratio, meat quality and blood biochemical parameters were calculated. Trouts from the experimental group, fed with supplement had 5.5% higher average final weight compared to this one of individuals from the control (P<0.05). The blood biochemical parameters glucose, ASAT and ALAT in control variant were higher compared to the values of that parameters of the fish from the experimental group (P>0.05). Electrolytes of blood such as phosphorus (P) had higher level in the experimental group (P>0.05) compared to the control group. Better growth performance and blood parameters were measured in trout fed sweet wormwood supplement.

Ontogenetic and diurnal variations of essential oil content of Hypericum montbretii Spach, cultivated in Kazdağı (Edremit/Balıkesir), Turkey

  1. Paşa1, E. Esendal2, T. Kiliç3


1Department of Plant and Animal Production, Altinoluk Vocational School, Balikesir University, Medicinal and Aromatical Plants Programme, Altinoluk, Edremit, Balikesir, Turkey

2Department of Field Crops, Faculty of Agriculture, Namik Kemal University, Tekirdağ, Turkey

3Faculty of Necatibey Education, Balikesir University, Balikesir, Turkey


DOI: 10.15547/ast.2018.03.050

(Manuscript received 16 April 2018; accepted for publication 8 July 2018)


Abstract. This research was carried out to determine the Hypericum montbretii Spach types essential oil content and composition, and its diurnal variations (9.00 am, 12.00 am and 16.00 pm) during the growing season of 2012. The plant was cultivated in the area of Mount Ida (Balikesir-Edremit), Turkey. The oil composition was determined with GC-MS. During the plant developmental stages the highest quantity of essential oil content (0.30-0.39%) was found at the full plant flowering stage and the lowest one at fresh fruiting stage (0.03-0.04%). Diurnal fluctuation in essential oils of whole plant was also observed – higher were the levels at noon (12.00 am) – 0.04-0.39% compared to the morning (9.00 am) and in the afternoon (16.00 pm). The oils consisted mainly of: at the vegetative stage – germacrene-D (6.9-11.7 %), gamma-Gurjunene (6.1-11.6%), 2-methyl octane (3.8-4.9%), δ-cadinol (2.7-4.8%) and phytol (2.9-4.5%); at the flowering stage – α-pinene (26.4-28.0%), undecane (14.1-16.0%), β-pinene (12.8-14.3%), delta-cadinene (6.8-8.0%) and caryophyllene (4.9-6.0%); at the fresh fruiting stage – amorphene (6.8-8.2%), β- caryophyllene (4.1-5.3%), delta-cadinene (5.0-5.5%) and α-cadinene (4.3-6.1%).


Analysis of structure and performance of paddy rice marketing in Adamawa state, Nigeria

Y. Dauna1, D.Y. Giroh1, W.B. Adamu2

1Department of Agricultural Economics and Extension, School of Agriculture and Agricultural Technology, Modibbo Adama University of Technology, Yola, Nigeria
2Yola Electricity Distribution Company Yerwa Business Unit, Maiduguri, Nigeria

(Manuscript received 20 March 2018; accepted for publication 31 May 2018)

Abstract. Many factors such as inadequate capital, poor infrastructure, poor price information could bring about distortion in the structure and performance of the market process resulting to the reduction in profit margin of marketers and a disincentive to present and prospective marketers of paddy rice. This study was conducted to analyze the structure and performance of paddy rice marketing in Adamawa State, Nigeria. The specific objectives were to examine the structure of rice market and to evaluate the performance of the market participants in the study area. Data were collected from 204 rice marketers using multi stage sampling technique. Herfindahl-Hirschman Index (HHI) was used to determine structure of the market, while Marketing Efficiency measure was applied in analyzing the market performance of the market participants. The HHI pooled results for year 2013, 2014 and 2015 revealed that paddy rice marketing in Adamawa State has a highly competitive market structure (11.38 and 71) with low (42% and 24%) marketing performance for retailers and wholesalers, respectively. To improve the performance of market participants, it is recommended that government should open up and rehabilitate the road network in the hinterlands to facilitate easy evacuation of agricultural inputs and commodities in and out of the market. Financial support and formation of unions would enable the marketers benefit from scale operation and enroll for training on entrepreneurship.

Meat quality and boar taint in entire male pigs fattened to 90 kg

I.G. Penchev1, S. Ribarski1, D. Dimitrov2, T. Stoyanchev3, S. Ivanova4

1Department of Morphology, Physiology and Nutrition, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria
2Slaughterhouse “Dimes 2000” EOOD, 6000 Stara Zagora, Bulgaria,
3Department of Food safety and control, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria
4Department of International cooperation and public relations, Agricultural Academy, Sofia, Bulgaria

(Manuscript received 23 February 2018; accepted for publication 10 May 2018)

Abstract. The aim of the present study was to investigate the chemical composition, technological traits and incidence of boar taint of meat from entire male pigs from two of the commonest breeds reared in Bulgaria: Landrace and Danube White. Fifty meat samples from entire male pigs (22 Landrace and 28 Danube White) fattened to average live weight of 90 kg were investigated. The chemical composition of Landrace pig meat was characterised with insignificantly lower fat and mineral content compared to Danube White meat. There were no significant differences between both breeds as technological properties of meat (pH, water holding capacity, and cooking loss) were concerned. The breed had a statistically significant effect on meat marbling (р<0.001). Landrace meat exhibited insignificantly higher incidence of the unpleasant boar taint as compared to Danube White meat (27.27% and 25.00%, respectively).

Influence of Goji berries on oxidative changes, microbiological status and chemical properties of sausages

  1. Mitev1*, A. Kuzelov1, E. Joshevska2

1Department of Food Technology, Faculty of Agriculture, University „Goce Delchev”, 2400 Shtip, Republic of Macedonia

2Department of Food Technology, Faculty of Biotechnical sciences, University “St. Kliment Ohridski”, Bitola, Republic of Macedonia

(Manuscript received 11 January 2018; accepted for publication 28 February 2018)

Abstract. The objective of this study was to investigate the influence of dried and minced goji berries over the oxidative changes (acid level, peroxide value), microbiological status and chemical properties on semi-durable sausage vacuumed and kept at a temperature of +4°С. Therefore, four types of sausages were made. The study was carried out on the 1st, 10th, 25th, 35th, and 50th day of the production of the sausage groups. The acid level of all examined groups of sausages is increasing, and the highest increase is registered in the control group of sausages (2.08). During the storage of the sausages, the peroxide value increased from the first to the fiftieth day. The presence of Listeria monocitogenes, Salmonella, Escherichia coli, Staphylococcus aureus was examined as well as the number of aerobic bacteria. In all examined groups, none of the abovementioned bacteria were identified. During the storage of sausages, the number of aerobic bacteria ranged from 2.08 to 2.93 log/CFU/g, which was much lower than the permissible limit (7.00 log/CFU/g) according to the national legislation. The fruit of goji berry doesn’t have a significant effect on the chemical composition of the studied sausage groups.

Organoleptic properties of white yam (Dioscorea rotundata poir) as affected by autoclaving time

  1. Ahmed1*, Y.B. Kiri2, M.S. Abubakar3

1Department of Crop Science, Adamawa State University, Mubi, Adamawa State, Nigeria

2Department of Animal Production, Adamawa State University, Mubi, Adamawa State, Nigeria

3Department of Soil Science, Federal University Dutse, Jigawa State, Nigeria

(Manuscript received 22 October 2017; accepted for publication 31 January 2018)

Abstract. This experiment examined the effect of processing white yam (Dioscorea rotundata poir) using autoclave under different heating times with the main objective of assessing its effects on the organoleptic properties (colour, mealiness, taste, softness and wetness). Yam tubers were washed, peeled and chopped into chunks. Treatments consisted of yam autoclaved at the temperature of 121oC and pressure of 100 kPa using five different autoclaving times (0, 5, 10, 15 and 20 min) laid out in a Completely Randomized Design (CRD). Descriptive sensory analysis was conducted by five trained panelists using a 7-point descriptive scoring method. Data collected were subjected to Analysis of Variance using SAS (1999). Least Significant Differences (LSD) tests were used to compare means that showed significant difference at P≤0.05. The results show that, autoclaving time had positive influence on organoleptic properties of white yam. The effect was more apparent on yam autoclaved for 5 minutes and therefore, recommended to be adopted for improved sensory attributes of boiled white yam.