scholarly journals Effect of Different Essential Oils on the Shelf Life of Concentrated Yogurt

Author(s):  
Claude Elama ◽  
Mohanad Alayoubi ◽  
Mohannad Jazzar ◽  
Fuad Al-Rimawi .

Aims: The objective of this study is to use different essential oils (cinnamon, clove, rosemary, almond sweet, sesame, wheat germ, and cedar wood) in concentrated yoghurt as antimicrobial agents to increase shelf life of concentrated yoghurt. Place and Duration of Study: Department of Food Technology, Faculty of Science and Technology, Al-Quds University, Palestine, between January 2015 to August 2016. Methodology: Essential oils were added to concentrated yogurt at a concentration of 250 μl\kg. Antibacterial activity and properties of major borne bacteria such as total aerobic count bacteria, yeast, mold, Staphylococcus aureus, were evaluated by plate count method, (pouring plate method). All yogurt samples were sensory evaluated for flavor, body and texture, and appearance. Total solid content, and titratable acidity of different yogurt samples were also determined. Results: Total solids and pH of concentrated yogurt samples treated with essential oils were only slightly affected. The best three essential oils used in terms of influence on total bacterial viable count and mold count were found to be cinnamon, clove and rosemary. The most acceptable organoleptic properties of treated concentrated yogurt were those samples treated with sesame and rosemary oils. Conclusion: The addition of cinnamon, clove and rosemary essential oils could increase the shelf life of concentrated yogurt.

2019 ◽  
pp. 1-24
Author(s):  
I. E. Mbaeyi-Nwaoha ◽  
A. M. Ezeoke

Aims: The broad objective of the research produce acceptable yoghurt flavoured with two accessions of passion fruit (pulp and skin) and evaluate its quality (physicochemical, phytochemical, microbiological, selected mineral and vitamin content). Study Design: The experimental design that was used is Completely Randomized Design. Place and Duration of Study: The study took place at the Department of Food Science and Technology, University of Nigeria, Nsukka between August 2016 and September 2017. Methodology: Yoghurt is a diary product obtained from lactic acid fermentation of milk.         Yoghurt and two accessions of passion fruit juices (Passiflora edulis f. flavicarpa O. Deg)          were processed to formulate enriched yoghurt in the following ratios 90:10, 80:20, 70:30,          60:40 and 50:50. Yoghurt without the passion fruit juice (100:0) served as the control. Based        on sensory evaluation, the best samples were subjected to physicochemical, phytochemical, microbiological, selected mineral and vitamin content evaluation using standard                  methods. The best enriched yoghurt samples were those in the ratio 90:10 and 80:20.                   Proximate composition of the enriched yoghurt samples significantly (p<0.05) differed with the controls. Results: Enriched yoghurt showed an increase in the protein content (3.70, 3.52, 3.86, 3.93, 3.94, 3.52%) than control (2.81%). The control had higher fat content (3.43%) than enriched yoghurt (2.93, 3.12, 3.14, 2.78, 3.03 and 2.90%). The ash content ranges from 0.59 - 0.82% while     addition of passion fruit juice caused pH to drop from 4.24 in the plain yoghurt to 4.18, 4.20 and 4.23 in the enriched yoghurt. The titratable acidity of yoghurt samples increased from 0.18 in the control to 0.72, 0.54, 0.52, 0.50 and 0.45 in enriched yoghurt. No direct relationship was observed      between the pH and the titratable acidity. The total solid content ranges from 4.57-30.03. The phytochemicals were in trace amount. There was no significant (p>0.05) difference in the tannin content. The titratable acidity of yoghurt samples increased from 0.013 µg in the control to 0.015, 0.027, 0.028, 0.016, 0.020 and 0.024 in enriched yoghurt. Significant (p<0.05) difference in the phenolic content value was observed among all the samples. The phenolic content in the yoghurt samples ranges from 0.06 to 0.10 mg/g. The mineral content and vitamin content of the      flavoured yoghurt samples significantly (p<0.05) differed with that of the control. An increase in the sodium content was observed in the samples from the control (168.24 mg/100 g) to the       enriched sample (209.31, 202.66, 169.48 and 192.82 mg/100 g). Similar increases were     observed for potassium, calcium, magnesium and phosphorus content of the samples.                 Enriched yoghurt showed an increase in the vitamin C content (6.40, 7.53, 7.29, 7.15 and          7.13 mg/g) than in the control (5.10 mg/g). Vitamin A content ranged from 14.96 µg/100g - 20.67 µg/100 g. The total viable count was higher in the control (5.67 × 105 cfu/ml) than in            enriched yoghurt. The mould count of the yoghurt samples varied from 0.33 × 101 cfu/ml - 1.58 × 103 cfu/ml. All the sensory attributes tested in the flavoured yoghurt samples significantly (p<0.05) differed. Conclusion: Yoghurt enriched with local specie passion fruit juice from pulp, was the most accepted.


2015 ◽  
Vol 731 ◽  
pp. 355-359 ◽  
Author(s):  
Ya Bo Fu ◽  
Wen Cai Xu ◽  
Dong Li Li ◽  
Xing Wang ◽  
Da Peng Yang

In order to extend the shelf-life of fresh strawberry, several packaging solutions were applied to investigate the modified atmosphere effect on strawberry. In the experiments, commercial PE and P# packaging was used as control, the effects of laboratory-made NK# packaging and styrene-butadiene rubber (SBR) modified LDPE packaging materials were comparatively studied. Various properties of strawberry samples were measured for 9 days at 10±1°C. The gas concentration in the package atmosphere and the physiological parameters including decay rate, hardness, weight loss, total solid content, as well as the sensory and taste evaluation were measured periodically. The experimental results show that SBR/LDPE and K-type packaging solutions can slow down the strawberry respiration and thus significantly extend the preservation period of fresh fruits.


2014 ◽  
Vol 4 (02) ◽  
Author(s):  
Rina S. Soetopo ◽  
Sri Purwati ◽  
Henggar Hardiani ◽  
Mukharomah Nur Aini ◽  
Krisna Adhitya Wardhana

A continuous pilot scale study has been conducted to investigate the effectiveness of anaerobic digestion of biological sludge. The sludge has a total solid content of 0.53% - 1.1%, pH of 7.20 to 7.32. Its organic content is about 97 %, The research were conducted in two stages, which are acidification (performed in 3 m3 the Continously Stirred Tank Reactor/CSTR at pH of 5.5 to 6.0) and methanation (performed in 5 m3 the Up Flow Anaerobic Sludge Blanket/UASB reactor at pH 6.5 to 7.0). The retention time (RT) was gradually shortened from 6 days to 1 day for acidification and from 8 days to 2 days for methanation. The results showed that operating the CSTR at the RT of 1 day and the organic loading of 8.23 g Volatile Solid (VS)/m3.day could produce Volatile Fatty Acid (VFA) at an average value of 17.3 g/kg VS.day. Operating the UASB reactor at the RT of 2 days and the organic loading (Chemical Oxygen Demand/COD) of 2.4 kg COD/m3.day could produce biogas at an average value of 66.3 L/day, with an average methane content of 69.9%, methane rate of 0.17 L CH4/g COD reduction or 19.06 L CH4/kg VS. Furthermore, methanation could reduce COD at an average value of 51.2 %, resulting in the effluent average value of COD filtrate and COD total of 210.1 mg/L and 375.2 mg /L, respectively.Keywords: acidification, methanation, CSTR, UASB, biogas ABSTRAKPercobaan digestasi anaerobik lumpur IPAL biologi industri kertas secara kontinyu skala pilot telah dilakukan di industri kertas dengan tujuan mengkaji efektivitas proses digestasi anaerobik dalam mengolah lumpur tersebut. Lumpur yang digunakan memiliki total solids sekitar 0,53% – 1,1%, pH netral (7,20 – 7,32) dengan komponen utama senyawa organik sekitar 97%. Percobaan dilakukan dalam dua tahap yaitu asidifikasi dalam reaktor CSTR berkapasitas 3 m3 pada pH 5,5 – 6,0 dan metanasi dalam reaktor UASB berkapasitas 5 m3 pada pH 6,5 – 7,0. Percobaan dilakukan dengan waktu retensi yang dipersingkat secara bertahap dari 6 hari ke 1 hari untuk proses asidifikasi dan dari 8 hari ke 2 hari untuk proses metanasi. Hasil percobaan menunjukkan bahwa pengoperasian reaktor CSTR dengan waktu retensi 1 hari dan beban organik 8,3 g VS/m3.hari dapat menghasilkan VFA rata-rata 17,3 g/kg VS.hari dengan kisaran 8,36 – 30,59 g/kg VS.hari, sedangkan pengoperasian reaktor UASB pada waktu retensi 2 hari dan beban organik 2,4 kg COD/m3.hari dapat menghasilkan biogas rata-rata 66,3 L/hari dengan kadar metana rata-rata 69,9% atau 0,17 L CH4/g COD reduksi atau 19,06 L CH4/kg VS. Selain itu proses metanasi dapat menurunkan COD terlarut rata-rata 51,2%, dengan konsentrasi efluen COD terlarut  rata-rata 210,1 mg/L dan COD total rata-rata 375,2 mg/L.Kata kunci: asidifikasi, metanasi, CSTR, UASB, biogas


1995 ◽  
Vol 32 (12) ◽  
pp. 91-97 ◽  
Author(s):  
P. Y. Yang ◽  
M. Kuroshima

In order to develop a simple operation for an anaerobic treatment process for highly concentrated pig wastewater for small producers, a three-stage anaerobic treatment process was investigated. The system provided a series of mixing, homogenization, biological reaction and final stabilization of concentrated pig waste (total solid content of 8–10%). The process provided a stable operational performance, simple operational procedure and well stabilized sludge effluent. It was also found that the system is economically feasible in Hawaii. Compared to the other treatment processes for highly concentrated pig waste, this process is considered as an appropriate alternative for the application of the small producers in land limited and tropical conditions. Also, the present treatment system can be easily developed into a prefabricated package plant which can minimize the on-site labor and building costs.


1960 ◽  
Vol 199 (4) ◽  
pp. 731-732 ◽  
Author(s):  
Jack R. Luick ◽  
Harold R. Parker ◽  
A. C. Andersen

A statistical study has been made of the composition of the major C-containing compounds taken from beagle dog milk during the 3rd through 5th week of lactation. The mean values are as follows: 26% total solids, 13% fat, 3.3% lactose and 9.8% protein. Total solid content was found to vary with fat content according to the equation: % total solids = 15.6 + 0.85 % fat.


2015 ◽  
Vol 1120-1121 ◽  
pp. 643-647
Author(s):  
Ya Bo Fu ◽  
Wen Cai Xu ◽  
Lu Fu ◽  
Dong Li Li ◽  
Jian Qing Wang

To reduce the loss of fresh fruits during transportation and storage, an active packaging (AP) material which could control release fungicide was prepared by melting, blowing film and composite method firstly. Then, its preservation effects on strawberry at different storage temperatures were investigated systematically. Several properties of preserved strawberries were measured periodically, including gas concentration of the package atmosphere and the physiological parameters contains decay rate, total solid content, as well as the sensory and taste evaluation were measured. The experimental results show that this AP material is helpful to fruit preservation, especially at lower temperature. It can prohibit the strawberry respiration, retard fungus growth and thus significantly extend the shelf-life of fresh strawberry.


2013 ◽  
Vol 144 ◽  
pp. 141-148 ◽  
Author(s):  
J.-C. Motte ◽  
R. Escudié ◽  
N. Bernet ◽  
J.-P. Delgenes ◽  
J.-P. Steyer ◽  
...  

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiang Chen ◽  
Zhi Deng ◽  
Dingwei Yu ◽  
Xiaofei Zhang ◽  
Zewei An ◽  
...  

Small nucleolar RNAs (snoRNAs) are a class of conserved nuclear RNAs that play important roles in the modification of ribosomal RNAs (rRNAs) in plants. In rubber trees, rRNAs are run off with latex flow during tapping and need to be regenerated for maintaining the functions of the laticifer cells. SnoRNAs are expected to play essential roles in the regeneration of rRNAs. However, snoRNAs in the rubber tree have not been sufficiently characterized thus far. In this study, we performed nuclear RNA sequencing (RNA-seq) to identify snoRNAs globally and investigate their roles in latex regeneration. We identified a total of 3,626 snoRNAs by computational prediction with nuclear RNA-seq data. Among these snoRNAs, 50 were highly expressed in latex; furthermore, the results of reverse transcription polymerase chain reaction (RT-PCR) showed the abundant expression of 31 of these snoRNAs in latex. The correlation between snoRNA expression and adjusted total solid content (TSC/C) identified 13 positively yield-correlated snoRNAs. To improve the understanding of latex regeneration in rubber trees, we developed a novel insulated tapping system (ITS), which only measures the latex regenerated in specific laticifers. Using this system, a laticifer-abundant snoRNA, HbsnoR28, was found to be highly correlated with latex regeneration. To the best of our knowledge, this is the first report to globally identify snoRNAs that might be involved in latex regeneration regulation and provide new clues for unraveling the mechanisms underlying the regulation of latex regeneration.


2020 ◽  
Vol 10 (1) ◽  
pp. 4966-4971

The role of liposome encapsulated flavourzymes on the ripening acceleration of Iranian white brined cheese has been studied. Liposomal enzymes (made by heating method) had a better performance than free enzymes, resulting in cheeses with lower total solid content and a higher concentration of soluble nitrogen (pH 4.6 and 12.5% trichloroacetic acid) through the ripening period (30 days at 12 oC). The ripening time could be shortened for 10 to 20 days. The entrapment efficiency and diameter of the liposomal enzyme were 26.5% and 189 nm, respectively. The proposed technology could be a potential treatment for the acceleration of Iranian white brined cheeses ripening.


2018 ◽  
Vol 55 (5A) ◽  
pp. 92
Author(s):  
Lai Quoc Dat

Beetroot (Beta vulgaris L.), which is rich in betacyanin and antioxidant compounds, has been utilized as a good source of red pigment and antioxidants. Nevertheless, these compounds are thermally sensitive, consequently, being degraded in processes conducted at high temperature. This research focused on effects of maltodextrin and hot air temperature on losses of betacyanin and antioxidant capacity in spray drying of beetroot juice. Results indicated that adding maltodextrin and temperature of hot air significantly influenced on loss by thermal effect, consequently, on the recovery yield of betacyanin and antioxidant capacity of beetroot juice powder. Adding maltodextrin enhanced protection of betacyanin and antioxidants in beetroot juice against thermal effect. Increasing temperature of hot air caused increase in loss by thermal effect of betacyanin and antioxidant capacity. The loss of antioxidant capacity by thermal effect was higher than that of betacyanin. Results also indicated that the suitable conditions of spray drying of beetroot juice are adding maltodextrin to reach 30 % w/w of total solid content and 150 oC of hot air temperature.   


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