End Of Storage Period Research Articles

Study of effect of 4 hexylresorcinol antioxidant on blackspot of cultured Shrimp (Litopenaeus vannamei) in freezing

This project was carried out in order to Study of possibity of uses from 4 hexyresorcinol for prevention of melanosis in cultured shrimp.Treatments including of samples processed with 0.15% concentration of 4 hexylresorcinol and control samples. The samples were kept at -18oC. Bacterial, chemical and sensory examinations were carried out for a period of six months. Statistically significant difference was observed in peroxide value, free faty acids, thiobarbotouric acid and trimethylamin in test samples compared with the control samples during storage period (P<0.05). No statistically significant difference was observed in and pH, TVN, protease and total bacterial counts in test and control samples during storage period(P<0.05). In sensory parameters including melanosis (colour), meat, eyes, cephalotrax, odour, logs, skins and antennae were observed meaningful different in test samples compared with control group (p<0.05). Test samples had better quality compared with the control samples. The test samples had a favorable quality until the end of storage period. But, the control samples had a favorable quality for a period of lower of one month.

Research Regarding the Evolution of Freshness State of European Catfish Meat Stored in Refrigerated Form

European catfish (Silurus glanis) the biggest fresh water fish from Europe is a breed that present a great interest among the fish breeders, due to its good growing rhythm, as well as among consumers, due to its remarkable sensorial properties. As in the case of other fish breeds, the main selling way is under refrigerated form. The current study aims to observe the qualitative modifications, which took place in refrigerated meat of Silurus glanis breed for a period of 16 days. Samples were evaluated by analyzing the sensorial features, pH and NH3, during 7 intervals corresponding to days 0, 2, 4, 8, 12, 14 and 16 of storage. Sensorial analysis qualified samples as being “very good” till day 4, “good” till day 8, “satisfactory” day 12, “inappropriate” day 14 and altered at the end of storage period. The pH recorded a value of 6.98 after slaughtering, constantly decreasing till day 4, so that in day 16 the obtained value to be 7.32 which show an inappropriate product for selling and consumption. Values obtained for NH3, present a close correlation with the other indicators utilized to evaluate the freshness state of fish meat, ranking the products as fresh till day 12 (27.10) and inappropriate for consumption starting with day 14.

English

The effects of overrun and glycerol as a cryoprotectant on viability of probiotics in frozen yogurt were investigated. Frozen yogurt was prepared with different types of probiotics (Lactobacillus acidophilus and Bifidobacterium lactis) along with normal yogurt starter culture (Streptococcus salivarius ssp. thermophiles and L. delbrueckii ssp. bulgaricus). Frozen yogurt mixture was supplemented with 1.5, 3 and 4.5% glycerol and was frozen with 60, 80 and 100% overrun. Viability of probiotic bacteria after freezing and during storage period of 12 weeks was investigated. Supplementation of glycerol in the mixture has improved the survival of L. acidophilus and B. lactis during the frozen storage. At the end of storage period the overall loss in viability of the L. acidophilus with 60, 80 and 100% overrun was 1.81, 1.96 and 2.24 log CFU/g, respectively. The B. lactis viability loss with 60, 80 and 100% overrun was 2.11, 2.26 and 2.26 log CFU/g, respectively. All the supplemented probiotics maintained the minimum concentration of 10 7 CFU/g in frozen yogurt during frozen storage, which is required for beneficial health effects in the host. © 2015 Friends Science Publishers

Peanut skin extract reduces lipid oxidation in cooked chicken patties

The objectives of this study were to evaluate the antioxidant capacity of peanut skin extract and its effect on the color and lipid oxidation of cooked chicken patties over 15 d of refrigerated storage. The extract was obtained using 80% ethanol and evaluated in terms of total phenolic content, reducing power based on the ferric reducing ability of plasma (FRAP) reagent, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. The patties were made with ground thigh fillets, chicken skin, and 2% salt. They were homogenized and divided into the following two groups: a control treatment without antioxidants and a peanut skin treatment with 70 mg gallic acid equivalent (GAE)/kg per patty. Analyses of the fatty acid profiles, instrumental colors (L*, a*, and b*) and thiobarbituric acid reactive substances (TBARS) were performed on d 1, 8, and 15 of storage at 1 ± 1ºC. The peanut skin extract resulted in a phenolic content of 32.6 ± 0.7 mg GAE/g dry skin, an antioxidant activity (FRAP) of 26.5 ± 0.8 6 μmol Trolox equivalent/g dry skin, and an efficient concentration (EC50) of 46.5 μg/mL. The total unsaturated fatty acid was approximately 73%, and 39% of this fatty acid content was monounsaturated. The peanut skin extract slowed the decrease in the a* values (P < 0.05) but reduced the L* and b* values compared to the control samples during storage (P < 0.05). Lipid oxidation was minimized by the peanut skin extract (P < 0.05), which resulted in a maximum value of 0.97 malondialdehyde (MDA)/kg compared to values that were close 19 mg MDA/kg patties in the control sample at the end of storage period. Thus, it can be concluded that although peanut skin extract causes little color change, it can be applied as a natural antioxidant to cooked chicken patties because it efficiently inhibits lipid oxidation in this product during refrigerated storage.

Oxidation Stability of Pig Liver Pâté with Increasing Levels of Natural Antioxidants (Grape and Tea).

The present study investigated the effect of the addition of increasing levels of the natural antioxidants tea (TEA) and grape seed extracts (GRA) on the physiochemical and oxidative stability of refrigerated stored pig pâtés. In addition, a synthetic antioxidant and a control batch were used, thus a total of eight batches of liver pâté were prepared: CON, BHT, TEA (TEA50, TEA200 and TEA1000) and GRA (GRA50, GRA200 and GRA1000). Pâté samples were analyzed following 0, 4, 8 and 24 weeks of storage. Color parameters were affected by storage period and level of antioxidant extract. Samples with TEA200 and GRA1000 levels of extracts showed lower total color difference between 0 and 24 weeks. At the end of storage period, the lower TBARs values were obtained in samples with the highest concentration on natural extract. Overall, the evolution of volatile compounds showed an increase in those ones that arise from the lipid oxidation and samples with TEA1000 extract showed the lowest values.

Effect of α-tocopherol on the storage stability of rista

The effect of incorporation of a-tocopherol (0.02%) on the quality and storage stability of Rista was studied. The pH and stability of raw emulsion of Rista formulated with a-tocopherol (T1) was significantly (P<0.05) lower than control emulsion (T0). In the cooked products, pH, cooking yield and proximate composition except ash content of Rista showed significant (P<0.05) differences. The overall palatability scores of Rista samples showed comparable results between the two groups. Another objective was to assess the effect of a-Tocopherol as antioxidant on the storage stability of Rista in refrigerated storage for 3 weeks at 4±1°C. The pH and moisture of Rista samples increased significantly (P<0.05) during storage. Thiobarbituric acid value of Rista samples increased significantly (P<0.05) with the advancement of storage. However, the values even at the end of storage period were well within the reported safe limits and not indicative of any rancidity. The total plate and coliform counts of Rista samples increased significantly (P<0.05) during storage. Yeasts and moulds were detected only from day 14 of storage and then increased significantly (P<0.05) by the end of day 21 of storage. Microbial counts in general remained low and well within permissible limits even at the end of the storage period. The results of sensory evaluation revealed a gradual decrease in the scores of various attributes with the advancement of storage. However, the scores even at the end of storage period remained generally in the range of above six indicating good acceptability of the product. It was concluded that the incorporation of α-tocopherol at 0.02% level, in Rista could be one of the alternatives to address the problem of lipid oxidation with beneficial effects on quality and storage stability.

EFFECT OF PREHARVEST CHEMICAL TREATMENTS AND MULCHING ON MARKETABILITY AND QUALITY OF 'DASHEHARI' MANGO

Ten-year-old ‘Dashehari’ mango trees of uniform vigour, size and maintained under consistent cultural practices were selected for the study. Eight treatments comprising of polythene mulching (during September) and preharvest chemical spray of calcium chloride (CaCl2) at 2.0, 4.0 and 6.0%, calcium nitrate (CaNO3) at 4.0%, potassium sulphate (K2SO4) at 1.0% and borax at 1.0% in combination with polythene mulching and control (water spray without mulching) were used at 30 days before anticipated harvest date. On the basis of pooled analysis of two years data, it was revealed that the treatment of borax at 1.0% with mulching was found more effective for increasing the fruit weight (161.66 g) and yield (37.20 kg tree-1). Its use was also found effective for increasing the TSS (16.22 and 19.51°B), total sugar (8.98 and 15.94%) and for decreasing the acidity (0.32 and 0.16%) at time of harvest and end of storage period, respectively, as compared to control. At the 10th day of storage the maximum fruit marketability (90.01%) and minimum physiological loss in weight (23.99%) were observed with the treatment of CaCl2 at 2.0% in combination with mulching. The effect of CaCl2 at 2 and 4% and CaNO3 at 4% on fruit marketability (90.01, 86.12 and 85.45%) was found statistically at par. Therefore, the use of CaCl2 at 2.0% seems more economical for improving the fruit marketability (shelf life). Thus the study indicated that preharvest application of CaCl2 at 2.0% with polythene mulching is effective for improving the fruit marketability and decreasing the physiological loss in weight (PLW), whereas, the borax at 1.0% with mulching proved effective for improving the fruit quality of ‘Dashehari’ mango.

Quality Evaluation of Yogurt Supplemented with Fruit Pulp (Banana, Papaya, and Water Melon)

Fruit yogurts with three different fruit pulps (banana, papaya and watermelon) at a ratio of 5%, 10% and 15% were prepared and stored at refrigeration condition for 15 days to study the physico-chemical and organoleptic changes over storage period. Addition of fruit pulp significantly (p<0.05) affected the physico-chemical and sensorial properties of fresh yogurt samples. Low synersis value with better textural quality were found in fruit yogurt samples compared with the control sample at refrigerated storage condition. Addition of 15% banana pulp resulted in lowest synersis in yogurt among all treatments. Papaya yogurt with all ratios were found most accepted, whereas watermelon yogurt samples were found least preferred to panelists at the end of storage period. Yogurt with maximum 15% fruit pulp, and especially papaya fruit could be recommended for large scale production of fruit yogurt.

Effect of chemical preservation over thermal processing on storage stability of tomato juice

The present investigation was carried out to study the effect of chemical treatments and storage on physicochemical, phytochemical compounds and antioxidant activity of tomato juice. Potassium metabisulfite, Sodium benzoate and their combination was used as chemical additives. Thermal treatment lead to the destruction of phytochemical nutrients and antioxidant activity. Non-significant (p≤0.05) decrease was found for physicochemical parameters and antioxidant activity. Out of chemical additives, Potassium Metabisulfite treated samples were found to retain the maximum nutritional quality and antioxidant activity at the end of storage period of six months. There was significant increase in the shelf stability of the chemically preserved juices than the thermally treated samples.

Effect of thermal processing and chemical preservatives on the physicochemical and phytochemical parameters of carrot juice

Carrot is an excellent source of β-carotene and antioxidants.. Carrot is a cool season crop and during the harvesting season, large quantities get spoiled due to excess production. So a long term preservation method is required that could be useful to prevent spoilage of carrot such that it could be consumed in off seasons as well. Keeping in view the nutrirional and therapeutic value of carrots carrot, juice was processed and treated with different chemical additives and tested for various physichochemical, phytochemical characteristics and antioxidant activity. At the end of storage period of six months, KMS treated samples were found to retain the maximum nutritional quality. There was significant (p≤0.05) increase in the shelf stability of the chemically preserved juices than the thermally treated samples.

Influence of Processing Variables and Storage on the Fruit Drink Developed from Taktir; Wild Fruit of Himalaya

Taktir is one of the fruits consumed by the large population of eastern Himalaya and other south east Asian countries. The fruits were harvested in five different harvesting times starting from second fortnight of April to mid of May to adjudge the best maturity time for fresh consumption and processing of fruits. The fruits harvested during 1st week of May were fully matured, rich in sugar, ascorbic acid (16. 54 mg/100 g), overall acceptability (7.46) and edible portion (79.35 %). Different combinations of juice percentage and total soluble solids were tried for the development of drink. A drink with 22.5 % juice and 40°B was found best by a panel of semi-trained judges and excelled in most of the chemical attributes. Taktir drink was further analyzed for chemical composition and microbial safety during 3 months of storage under room temperature and low temperature in day light and dark condition packed in pet and glass bottles. TSS, pH and reducing sugar increased while acidity, ascorbic acid and total sugar dropped off. Anthocyanin was degraded with the increase in storage period. The ‘a’ value was found to be decreasing as the storage interval increased. However yeast, mould, E. coli and total plate counts could not be detected in the beverage. The maximum score (8.1) for over all acceptability was observed with 4 °C Dark PB (pet bottles) at the end of storage period.

Effect of Packaging Methods and Storage Time on Oxidative Stability of Traditional Fermented Sausage

In this paper influence of packaging method (vacuum and modified atmosphere packaging) on lipid oxidative stability and sensory properties of odor and taste of the traditional sausage Petrovska klobasa were examined. These parameters were examined during storage period (7 months). In the end of storage period, vacuum packed sausage showed better oxidative stability. Propanal content was significantly lower (P<0.05) in vacuum packed sausage compared to these values in unpacked and modified atmosphere packaging sausage. Hexanal content in vacuum packed sausage was 1.85 μg/g, in MAP sausage 2.98 μg/g and in unpacked sausage 4.94 μg/g. After 2 and 7 months of storage, sausages packed in vacuum had the highest grades for sensory properties of odor and taste. Keywords—Lipid oxidation, MAP, sensory properties, traditional sausage, vacuum.

Researches Regarding the Influence of Storage Conditions upon the Quality of Cherry Fruits

The studies concerning the cherry fruits are concentrated on reducing the losses during the storageperiod, subject also treated in this paper. The fruit cherries from Hedelfinger and Stella varieties wereharvested at the consumption maturation phase. After harvest and at the end of storage period, thefruits were weighed in order to establish the weight losses and also to observe the percentage of therotten fruits. The results obtained show that the shelf life of fruits reaches 12 days (Hedelfinger) or 16days (Stella) in refrigerated conditions and modified atmosphere package and only 5 days (Hedelfinger)or 6 days (Stella) in ambient conditions. The total losses during storage period were between 11.1% inrefrigerated conditions and modified atmosphere package and 36.9% in ambient conditions.A 5-7 daysdifference was observed between the storage period in cold conditions, without covered package (V3)and the storage period in cold conditions and covered with semipermeable film plastic (V1), proving thefavorable effect of the semipermeable film plastic on the cherries storage period. The lowest percentageof damaged fruits caused by Monilinia laxa (3.4% Hedelfinger and 3% Stella) was recorded at the V1variant, the other variants recording bigger losses.

Evaluation of Physical-Chemical Indexes, Sugars, Pigments and Phenolic Compounds of Fruits from Three Apple Varieties at the End of Storage Period

Apples are the most cultivated and consumed fruits in the world. They not only taste great, but there are also rich sources of monosaccharides, pigments, fibers, functional compounds such as polyphenols which are well-known for their antioxidant action. Due to the high level of apples consumption, it is important to monitor and know the detailed chemical composition of this fruits on the market shelf. The aim of this paper was to study the detailed chemical composition of apples from three varieties. Samples from three varieties (Ionathan, Golden Delicious and Starkrimson) were taken from the Romanian market. Individual sugars composition was performed by HPLC, total polyphenols content by Folin Ciocalteu method, antioxidant capacity by using the DPPH test, while pigments were analysed by spectrophotometric specific methods and the total starch content measured by a polarimetric method. Water content, acidity, total soluble solids and pH were also monitored through specific methods. There were found differences between varieties particularly in relation to the polyphenols content, carotenoids and chlorophyll. Regarding the individual sugars composition, fructose and glucose were predominant followed by sucrose for all samples. Values of starch, moisture, acidity, total soluble solids and the pH were according to other apple varieties found in literature. These results provide important information regarding the chemical composition of apple varieties from Romanian market, for both human direct consumption and industrial processing.

Physicochemical properties and stability of black cumin (Nigella sativa) seed oil as affected by different extraction methods

Black cumin (Nigella sativa) oil (BCO) was recovered using different extraction techniques including solvent free system (cold-pressing) and solvent extracted systems (Soxhlet and microwave assisted). Oils were analyzed for the composition of fatty acids and bioactive compounds (sterols, tocopherols, chlorophyll, carotenoid and phenolics profile) and for some physicochemical properties [free fatty acid, peroxide value (PV), refractive index, and ultraviolet (UV) absorption at K232 and K270]. Antiradical power (AP) of oils was also evaluated, wherein cold-pressed oil had stronger AP than solvent extracted oils. Phenolic profiles analyzed by HPLC revealed that thymoquinone was the main phenolic compound wherein high levels of benzoic and p-hydroxy benzoic acids were found in cold pressed-BCO. Oxidative stability (OS) of oils was evaluated during accelerated oxidation conditions (oven test at 60°C and Rancimat test at 110°C). The greatest induction period was 19.6h for Soxhlet-extracted BCO, and the lowest induction period was 3.48h for cold-pressed BCO. PV of cold-pressed BCO reached 85.3meq O2/kg oil, while PV of the other extracted oils were under 27.0meq O2/kg oil at the end of storage period.

COLOR STABILITY OF STRAWBERRY JAM FORTIFIED BY PURPLE CARROT PUREE

The discoloration of strawberry products due to the rapid degradation of pigments is considered as one of the most quality defects that affect their acceptance. Therefore, in the present study, the objective was to investigate the possibility to improve the color stability of strawberry jam by using purple carrot puree. The obtained results declared that purple carrot puree characterized by high content of anthocyanins and total phenols compared to strawberry puree. Furthermore, the contents of individual anthocyanins were analyzed by HPLC. The highly stable acylated anthocyanins pigments represented 66.64% of total anthocyanins in purple carrot compared to 20.6 % from strawberry. Cyandin-3-xylosyl-glucosyl-galactoside acylated with Ferulic acid was the predominant anthocyanin in purple carrot while Pelargonidin 3-glcosside was the major component in strawberry. Purple carrot puree was adding by 15, 20 and 30% to strawberry puree during jam processing. The jams were monitored over a period of 6 month of storage under normal conditions of light exposure and room temperature. The results revealed that pH value, viscosity, total anthocynin and total phenol contents were increased gradually by increasing the amount of purple carrot and markedly decreased the degradation of anthocyanin during storage period by 53.2, 52.9, 18.0 and 7.3%in control,15, 20 and 30% samples respectively. Furthermore, the color of jams were controlled during the storage period. L∗, a∗ , b∗, hue o and chroma values showed that the color of strawberry jams containing purple carrot was improved and showed stability. The results of sensory evaluation revealed that the jam of 20% purple carrot treatment obtained the highest overall acceptability score at the end of storage period. Finally, from all results obtained, it can be concluded that the addition of purple carrot up to 20% during strawberry jam processing maintained the color of jam without any effect on their acceptance.

EXISTENCE OF LISTERIA SPECIES IN FRESHWATER FISH AND ITS CONTROL USING SANITIZED ICE

The present study was designed to investigate the occurrence of Listeria spp. in two of economically important freshwater fish species namely Oreochromis niloticus (tilapia) and Clarias gariepinus which were collected from commercial fish markets in Assiut, also to explore the efficiency of five ice formulations : tab water ice (control), three ices sanitized using trisodium phosphate (TSP) 2.5%,5% and 10% in addition to an ice sanitized using sodium acetate (SA) 2.5% against Listeria monocytogenses (LM) artificially loaded on Tilapia fish at level of (5.5log10 CFU/g) and the effect of formulated ices on ice stability, sensory quality and pH of fish during storage at room temperature (25 oC). The microbiological analysis of sampled fish revealed that sampled fish represents health hazard to consumer and contact surfaces. O. niloticus were more contaminated with Listeria spp. compared with C.gariepinus samples (16%and 4%, respectively). The contamination with LM in both fish species was parallel (4%) while Listeria innocua was present in O. niloticus only (12%). Storage of Tilapia loaded with LM (5.5 log10CFU/g) on formulated crushed ices separately for 4h revealed that both (SA) 2.5% and (TSP) 10% ices had the efficacy (P>0.05) of reduction of LM on fish and in water from melted ice when compared with the control thus improves the safety and reduces the potential for cross contamination. Formulated ices were more stable (slow melting rate) when compared with the control. Storage of fish on formulated ices for 4h was not associated with any defects in sensory parameters (P>0.05). A desirable lowering of pH values of stored fish was noticed by application of (SA) 2.5% ice while (TSP) 10%ice resulted in a significant rise (P<0.05) of pH at the end of storage period. Despite this study demonstrates the effectiveness of (SA) 2.5% ice or (TSP) 10%ice application to control the growth of LM to enhance the microbiological safety of raw fish, (SA) 2.5% ice has the advantages of its organic origin and its desirable lowering pH of stored fish. The public health importance of the organism was discussed and the suggestive measures for control were outlined.

DISEASE PROGRESSION POTATOES (SOLANUM TUBEROSUM L.) DURING STORAGE DEPENDING ON THE TERM OF PLANTING AND PROCESSING DRUGS BIOLOGICAL AND CHEMICAL ORIENTATION IN WESTERN POLISSYA

Application of biological preparations (Planriz, Fitotsid, Diazofit and Fosfoenterin) and chemicals (MC Ridomil Gold 68WG) in the conditions of Western Polissya has reduced the pathogens infection in 1.6–2.2 times at treatment of tubers prior to planting, plants during budding and flowering stages, as well as before storage. The least general disease development was observed in variants with Planriz (2.0–2.5 l/t), and the composition of biological preparation Planriz, Diazofit and Fosfoenterin (2.0–2.5 + 0.2 + 0.2 l/t). Among the total number of diseases the wet bacterial rot was 14.3–30.0%, Phoma exigua – 6.7–16.3%, Fusarium spp. – 62.5–71.1%. The development of Fusarium spp. has increased in 1.6 times at the end of storage period, Phoma exigua – in 4 times. The level of bacterial rot development had remained unchanged for the tubers of the Lileya cultivar planted in mid-May. The planting dates had almost no influence on the prevalence of disease at storage of the potatoes of Skarbnitsa cultivar.

In-package atmospheric pressure cold plasma treatment of cherry tomatoes

Cold plasma is increasingly under research for decontamination of foods, especially fresh fruits and vegetables. The effect of cold plasma on food quality, however, remains under researched. This study investigates the effects of cold plasma generated within a sealed package from a dielectric barrier discharge on the physical quality parameters and respiration rates of cherry tomatoes. Respiration rates and weight loss were monitored continuously, while other parameters are reported at the end of storage period. Differences among weight loss, pH and firmness for control and treated cherry tomatoes were insignificant towards the end of storage life. Changes in respiration rates and colour of tomatoes were recorded as a function of treatment, which were not drastic. The results implicate that cold plasma could be employed as a means for decontamination of cherry tomatoes while retaining product quality.

Detoxification of aflatoxin M1 in yoghurt using probiotics and lactic acid bacteria

Probiotics and lactic acid bacteria (LAB) are widely used in food fermentation and preservation. This study was carried out to assess the potential of five strains of LAB and bifidobacteria to remove aflatoxin M1 (AFM1) from yoghurt. The stability of the AFM1 complexes formed with them in both viable and non-viable (heat- or acid-treated) forms was assessed by repetitive aqueous extraction. Strains with high ability in removing AFM1 were selected to study its ability to remove AFM1 from spiked milk during yoghurt production and storage. Three treatments from yoghurt that produced from spiked milk were studied. Treatment A was the control using fermented yoghurt culture (Streptococcus thermophilus and Lactobacillus bulgaricus). Treatment B was fermented by 50% yoghurt culture (S. thermophilus and L. bulgaricus) and 50% Lactobacillus plantrium. Treatment C was fermented by yoghurt culture (S. thermophilus and L. bulgaricus) and 50% Lactobacillus acidophilus. The samples were collected during different storage (5 °C) times (1, 3, 5 and 7 days) to determine the ability of the stains to reduce AFM1. The results indicted that there were significant differences (P < 0.05) between the strains in their ability to reduce AFM1 in MRS broth media in the viable stage, heated stage and acid treatment. L. plantrium was the highest strain capable of removing AFM1. Yoghurt fermented by 50% yoghurt culture (S. thermophilus and L. bulgaricus) and 50% L. plantrium recorded the highest reduction in the level of AFM1 at the end of storage period. The results revealed the possibility of using some strains of LAB and bifidobacteria in detoxification of AFM1-contaminated foods.