Effect of ohmic heating on texture,microbial load,and cadmium and lead content of Chilean blue mussel (Mytilus chilensis)

The effect of ohmic heating (OH) on the texture, microbial load, and cadmium (Cd) and lead (Pb) content was evaluated in Chilean blue mussel (Mytilus chilensis) at shucking and subsequent canning. Mussel samples were processed by OH and blanching (BLAN) at 50 ± 1 °C, 70 ± 1 °C and 90 ± 1 °C for shucking and then canning at 115 °C for 20 min. The Cd and Pb content in fresh mussels was 2.47 ± 0.18 μg g^− 1 and 5.26 ± 0.55 μg g^− 1 dry weight (dw). The greatest reduction in Cd content was reached at 90 ± 1 °C by OH with 1.67 ± 0.06 μg g^− 1 (dw) and 1.69 ± 0.08 μg g^− 1 (dw) by BLAN. At the same temperature, the Pb content was reduced to 4.18 ± 0.24 μg g^− 1 dw for OH and 4.14 ± 0.30 μg g^− 1 dw for BLAN. The cutting strength of fresh samples (21.35 ± 2.44 N) significantly decreased in samples processed by OH (15.65 ± 1.36 N) at 90 ± 1 °C compared with BLAN samples (20.41 ± 3.16 N) at the same temperature. The initial mean count for mesophilic aerobic microorganisms and Enterobacteriaceae was 3.8 log cfu/g and 2.5 log cfu/g, respectively. The mesophilic aerobic microorganism count was reduced by 1.7 logarithmical units, while Enterobacteriaceae counts were reduced to undetectable levels by OH at 90 ± 1 °C.Industrial relevanceHigh temperature short time (HTST) processes rely on rapid convection heat transfer and are thus well suited to liquid foods. But, they are, however, limited in application to particulates since, for particles more than a couple of millimeters thick, the processing time is insufficient for heat to transfer to the center to give sterility. Ohmic heating is an emerging technology and very promising in food industries. It is a thermal process in which heat is generated internally in food and acts as a resistance to the flow of alternating electric current. This type of treatment prevents overheating by producing less deterioration in food components. It is a rapid procedure that allows food to conserve its natural properties; microorganisms and enzymes are also inactivated. The purpose of the present work was to evaluate the effect of Ohmic heating on mechanical properties, microbial load, Cd and Pb content in the opening and subsequent canning of Chilean blue mussel (Mytilus chilensis). This information could be used for the seafood industries in order to improve thermal heating processes in mussels.     

Modeling the effect of temperature on bioaccumulation of metals by a marine bioindicator organism, Mytilus edulis

To determine whether regional or seasonal variability in water temperatures might affect the bioaccumulation of metals by marine invertebrates, we used a biokinetic/bioenergetic approach to model metal bioaccumulation (Ag, Am, Cd, Co, Se, and Zn) from dietary and dissolved sources by blue mussels, Mytilus edulis, acclimated at 2 and 12 degrees C. Accumulation of metal from the aqueous phase was not affected by temperature. However, Ag, Am, and Zn from diet were respectively accumulated up to 5.7-fold, 5.3-fold, and 2-fold more effectively at 2 degrees C than at 12 degrees C, largely because these three metals were assimilated from food more effectively at the lower temperature. In contrast, bioaccumulation of Cd, Co, Se from diet was not substantially affected by temperature even though efflux constants for these metals were up to 4-fold lower at 2 degrees C than at 12 degrees C. Total bioaccumulation of Ag, Am, and Zn was up to 1.7-3.6-fold higher at 2 degrees C than at 12 degrees C, with the largest differences predicted for high food conditions. Temperature-related variability in bioaccumulation of metals should be considered when interpreting patterns in metal tissue concentrations and when adapting management strategies developed for temperate seas to polar areas.     

Effects of ball‐milling treatment on mussel (Mytilus edulis) protein: structure,functional properties and in vitro digestibility

In this study, the effects of ball‐milling treatment on structural properties and functional properties of mussel protein were investigated. In vitro protein digestibility and free amino acid contents were also evaluated. Ball‐milling treatment did not change the primary structure of mussel protein, but caused changes of secondary structure. The tertiary and quaternary structure also changed. After 20 min of ball‐milling treatment, the whiteness and oil‐binding capability of mussel protein significantly improved from 13.67 to 26.62 and 43.76% to 196.00%, while the protein solubility and water‐holding capability of mussel protein significantly decreased from 74.89% to 53.10% and 215.67% to 90.91%. Ball‐milling treatment increased the in vitro digestibility significantly. These results provide theoretical basis for the utilisation of mussel protein in food industry.     

Studies on the skin uptake and efflux kinetics of N-phenyl-p-phenylenediamine: an aromatic amine intermediate

N-phenyl-p-phenylenediamine (N-PPDA), an industrial intermediate and hair dye ingredient, has been implicated in a variety of toxic symptoms including cutaneous manifestations. However, the role of physiological factors that may determine and modify its absorption and transport within and through the skin is not fully understood. The present study reveals that N-PPDA binds readily to skin showing saturation kinetics with K m and V_max of 2.54 × 10⁻⁴ M and 4.76 μmol g⁻¹ skin, respectively. The uptake was dependent upon the area of skin, concentration of the amine, exposure time, temperature and pH of the vehicle. Heat treatment facilitated the binding but temperatures abouv 50° caused significant lowering of the uptake, indicating the possible involvement of collagen matrix. Skin lipids also contributed in the binding of N-PPDA. Bioinhibitors such as KCN, sodium arsenate, NaF, N-ethylmaleimide, cycloheximide, iodoacetic acid and 2,4-dinitrophenol had no effect on the uptake potential, suggesting it to be a non-energy dependent process. Most of the skin-bound N-PPDA was effluxed through serum proteins reaching the target organs via systemic circulation.     

煎炸油中总极性物质对细胞抑制和诱导凋亡的影响

研究煎炸油中总极性物质(TPM)对细胞的生长抑制和诱导凋亡。结果表明:1.0mg/m L的TPM作用于Hep G2细胞24、48、72h后,细胞增殖抑制率分别为9.8%、12.6%、16.1%;流式细胞仪结果显示,随着TPM浓度的增加,加药组细胞凋亡率逐渐增加,G0/G1期细胞数目逐渐减少,S期细胞数目逐渐增多,说明TPM对He PG2细胞增殖的抑制发生在S期。     

煎炸油中总极性物质对细胞抑制和诱导凋亡的影响

研究煎炸油中总极性物质(TPM)对细胞的生长抑制和诱导凋亡。结果表明:1.0mg/m L的TPM作用于Hep G2细胞24、48、72h后,细胞增殖抑制率分别为9.8%、12.6%、16.1%;流式细胞仪结果显示,随着TPM浓度的增加,加药组细胞凋亡率逐渐增加,G0/G1期细胞数目逐渐减少,S期细胞数目逐渐增多,说明TPM对He PG2细胞增殖的抑制发生在S期。      

Invited review: New perspectives on the roles of nutrition and metabolic priorities in the subfertility of high-producing dairy cows

Management, nutrition, production, and genetics are the main reasons for the decline in fertility in the modern dairy cow. Selection for the single trait of milk production with little consideration for traits associated with reproduction in the modern dairy cow has produced an antagonistic relationship between milk yield and reproductive performance. The outcome is a multi-factorial syndrome of subfertility during lactation; thus, to achieve a better understanding and derive a solution, it is necessary to integrate a range of disciplines, including genetics, nutrition, immunology, molecular biology, endocrinology, metabolic and reproductive physiology, and animal welfare. The common theme underlying the process is a link between nutritional and metabolic inputs that support complex interactions between the gonadotropic and somatotropic axes. Multiple hormonal and metabolic signals from the liver, pancreas, muscle, and adipose tissues act on brain centers regulating feed intake, energy balance, and metabolism. Among these signals, glucose, fatty acids, insulin-like growth factor-I, insulin, growth hormone, ghrelin, leptin, and perhaps myostatin appear to play key roles. Many of these factors are affected by changes in the somatotropic axis that are a consequence of, or are needed to support, high milk production. Ovarian tissues also respond directly to metabolic inputs, with consequences for folliculogenesis, steroidogenesis, and the development of the oocyte and embryo. Little doubt exists that appropriate nutritional management before and after calving is essential for successful reproduction. Changes in body composition are related to the processes that lead to ovulation, estrus, and conception. However, better indicators of body composition and measures of critical metabolites are required to form precise nutritional management guidelines to optimize reproductive outcomes.The eventual solution to the reduction in fertility will be a new strategic direction for genetic selection that includes fertility-related traits. However, this will take time to be effective, so, in the short term, we need to gain a greater understanding of the interactions between nutrition and fertility to better manage the issue. A greater understanding of the phenomenon will also provide markers for more targeted genetic selection. This review highlights many fruitful directions for research, aimed at the development of strategies for nutritional management of reproduction in the high-producing subfertile dairy cow.     

New perspectives on the regulation of iron absorption via cellular zinc concentrations in humans

Iron deficiency is the most prevalent nutritional deficiency, affecting more than 30% of the total world's population. It is a major public health problem in many countries around the world. Over the years various methods have been used with an effort to try and control iron-deficiency anemia. However, there has only been a marginal reduction in the global prevalence of anemia. Why is this so? Iron and zinc are essential trace elements for humans. These metals influence the transport and absorption of one another across the enterocytes and hepatocytes, due to similar ionic properties. This paper describes the structure and roles of major iron and zinc transport proteins, clarifies iron-zinc interactions at these sites, and provides a model for the mechanism of these interactions both at the local and systemic level. This review provides evidence that much of the massive extent of iron deficiency anemia in the world may be due to an underlying deficiency of zinc. It explains the reasons for predominance of cellular zinc status in determination of iron/zinc interactions and for the first time thoroughly explains mechanisms by which zinc brings about these changes.     

Dairy farmers' perspectives on providing cow-calf contact in the pasture-based systems of New Zealand

Separation of the cow and calf shortly after birth is a common practice on commercial dairy farms around the world, but there are emerging concerns about this practice among citizens and other stakeholders. Continuous improvement of on-farm management practices in collaboration with dairy sector stakeholders increases the likelihood that farming systems evolve in a way that is consistent with societal expectations. Few commercial dairy farms provide extended cow-calf contact, and there is little understanding of how dairy farmers view this practice. This study examined the views of New Zealand dairy farmers toward providing cow-calf contact, particularly the barriers to adopting such a system in a seasonal-calving pasture-based dairy system. Standard farm practice in New Zealand is to remove the calf from the cow around 24 h (but could be up to 48 h) after birth. These conventional farmers (n = 63) were randomly selected from the database of all dairy farmers in New Zealand and telephone-interviewed using a semistructured interview format. Their responses to questions about providing cow-calf contact (defined as contact beyond the standard practice of 48 h) were analyzed using thematic analysis. Three major themes of concern were identified by these farmers about providing cow-calf contact as follows: (1) poor animal welfare, especially the risk of mastitis in the dam, inadequate colostrum for the calf, increased stress from delayed separation, and lack of shelter for calves while outdoors with the cow; (2) increased labor and stress on staff; and (3) system-level changes required, including infrastructure and herd management. Many of these concerns stemmed from challenges related to the nature of large-scale seasonal-calving pasture-based dairy systems, where a large number of calves are born in a short period of time and may be exposed to inclement weather in late winter in some areas. Several small-scale farmers (n = 4) providing cow-calf contact for longer than standard practice of 48 h were also interviewed; all permitted contact for at least 4 wk. These farmers also felt that animal welfare and health were important, and that this was promoted in their cow-calf contact systems. Concerns about colostrum and mastitis, for example, were not raised by these farmers, but they did agree that additional infrastructure and shelter were important considerations for cow-calf contact systems. Some conventional farmers expressed cognitive dissonance in that they theoretically preferred cow-calf contact but could not see it being realistic or practical to implement. Farmers currently providing longer cow-calf contact may be a useful resource for better understanding of how practical and economical cow-calf contact systems could be adopted on commercial pastoral dairy farms.     

Ozone in wineries and wine processing: A review of the benefits,application, and perspectives

Ozone (O₃) is an emerging eco-friendly technology that has been widely used in the beverage industry due to its broad spectrum of usages, such as fermentation, microbial inactivation, Clean-in-Place (CIP) systems, and postharvest treatment. Wine is among the most financially profitable sectors of the beverage industry. Ozone technology as an alternative approach to conventional methods to inhibit microbes in wine processing and wineries has attracted researchers' attention as this emerging technology will probably play important roles in wineries in the future. This review discusses the prospective applications of ozone in winemaking and wineries and elaborates on ozone's antimicrobial effects on the control of the broad spectrum of microorganisms during wine processing. Also, this paper provides discussions on its effects of O₃ on wine quality and the benefits this emerging technology can bring to wineries. Ozone treatments can improve yeast fermentation by impacting the yeast ecology of postharvested wine grapes, mainly by affecting apiculate yeasts and adjusting the population of undesirable yeasts, such as Brettanomyces spp., during the fermentation process. Furthermore, ozone treatment may enhance wine's anthocyanin concentration, physicochemical properties, color, pH, oxidative stability, and concentration of pleasant volatile compounds and esters. This article presents important information to have a better understanding of the impact of ozone treatment on different stages of wine preparation.     

Atosiban, an oxytocin receptor blocking agent: pharmacokinetics and inhibition of milk ejection in dairy cows

Plasma concentrations of the oxytocin receptor blocking agent Atosiban were measured at 2, 4, 10, 15 and 20 min after injection of 5, 10, 20 and 50 micrograms Atosiban/kg body weight in six dairy cows. The half life of Atosiban was 18 min and the total body clearance was 3301 ml/min. Intramammary pressure (IMP) within the teat cistern was measured in six cows before and after i.v. injection of 0 or 20 micrograms Atosiban/kg body weight and repeated injections of 0.2 or 0.5 i.u. oxytocin. IMP was also measured in eleven cows after injection of 0, 10 or 50 micrograms Atosiban/kg body weight: in seven during oxytocin infusions, in four after oxytocin injections in successively increasing dosages (0.05, 0.1, 0.2, 0.5, 1 and 10 i.u.). The occurrence of milk ejection was indicated by a rise in IMP. After injection of 20 micrograms Atosiban/kg body weight, 0.2 i.u. oxytocin did not induce an IMP rise before 48 min, whereas 0.5 i.u. oxytocin induced an IMP rise within 4 min. The time from the start of infusion until the beginning of the IMP rise and the duration of IMP rise during oxytocin infusions both increased, whereas the IMP rise itself was diminished by increasing Atosiban dosages. The amount of injected oxytocin necessary to induce an IMP response increased with increasing Atosiban dosages. Atosiban was shown to have a powerful effect in inhibiting milk ejection in dairy cows.     

Comparison of acids on the induction of an Acid Tolerance Response in Salmonellatyphimurium, consequences for food safety

Salmonellatyphimurium inactivation at pH 3.0 in Brain Heart Infusion (BHI) and Meat Extract (ME) was studied using stationary-phase cells grown in non-acidified BHI (pH 7.4) and ME (pH 6.6) and acidified BHI and ME at pH values of 6.4, 5.4 and 4.5 with acetic, ascorbic, citric, lactic, malic and hydrochloric acids. Cells grown in buffered BHI (pH 7.0) were used as non-acid adapted control cells.     

A critical review on biodegradable food packaging for meat: Materials,sustainability, regulations,and perspectives in the EU

The development of biodegradable packaging is a challenge, as conventional plastics have many advantages in terms of high flexibility, transparency, low cost, strong mechanical characteristics, and high resistance to heat compared with most biodegradable plastics. The quality of biodegradable materials and the research needed for their improvement for meat packaging were critically evaluated in this study. In terms of sustainability, biodegradable packagings are more sustainable than conventional plastics; however, most of them contain unsustainable chemical additives. Cellulose showed a high potential for meat preservation due to high moisture control. Polyhydroxyalkanoates and polylactic acid (PLA) are renewable materials that have been recently introduced to the market, but their application in meat products is still limited. To be classified as an edible film, the mechanical properties and acceptable control over gas and moisture exchange need to be improved. PLA and cellulose-based films possess the advantage of protection against oxygen and water permeation; however, the addition of functional substances plays an important role in their effects on the foods. Furthermore, the use of packaging materials is increasing due to consumer demand for natural high-quality food packaging that serves functions such as extended shelf-life and contamination protection. To support the importance moving toward biodegradable packaging for meat, this review presented novel perspectives regarding ecological impacts, commercial status, and consumer perspectives. Those aspects are then evaluated with the specific consideration of regulations and perspective in the European Union (EU) for employing renewable and ecological meat packaging materials. This review also helps to highlight the situation regarding biodegradable food packaging for meat in the EU specifically.     

Study on the behavior of the trace metal and macro minerals in Mytilus galloprovincialis as a bioindicator species: the case of Marmara Sea, Turkey

Sea food is a major source of animal protein. Marine foods are very rich sources of mineral components. The total content of minerals in the raw flesh of marine fish and invertebrates is in the range of 0.6–1.5% wet weight. The contents of Na, K, Ca, Mg and P are up to 1 mg/100 g, whereas those of Fe, Zn, I are less than 1 mg/100 g. Mussels (Mytilus galloprovincialis) were investigated for macro and trace element composition throughout the year. Ranges of moisture, ash, protein and fat contents were 79.76–87.46 g/100 g, 1.06–2.06 g/100 g, 7.28–12.65 g/100 g and 0.33–3.49 g/100 g, respectively. While the highest protein and fat values were found in the summer (July–August), the highest moisture and ash contents were found in the winter (December–January). The contents of highest Na, K, Ca were found in the summer. Cadmium, lead and copper were found to be below the legislative limits throughout year. High levels of mercury were found in January and October. It should be discussed whether mussel may provide an alternative source of mineral for healthy nutrition.     

New perspectives in safety and quality enhancement of wine through selection of yeasts based on the parietal adsorption activity

The present article aims to review research papers that focus on the parietal adsorption activity of wine yeast and on its contribution to the enhancement of wine safety and quality. There is a great diversity among yeasts for their parietal adsorption activity: the outermost layer of the cell wall has a chemical composition that notably varies from yeast to yeast. Parietal mannoproteins can contain phosphate, pyruvate, or glucuronic acid, which impart negative charges, modifying the electrostatic and ionic interactions with wine components. The following could give a good reason to propose a specific selection of wine yeasts based on their parietal adsorption activity to improve wine safety and quality: (a) ochratoxin A content of wines is greatly reduced by expressly selected yeasts, sequestering the toxin during winemaking; (b) yeast influences concentration and composition of phenolic compounds in wine, above all by adsorbing them on cell wall; (c) among grape pigments, anthocyanins, in particular, may be adsorbed by yeast cell wall; and (d) yeast can also interact with wine colour producing anthocyanin-beta-d-glucosidase, pyruvic acid, and acetaldehyde or releasing mannoproteins and different polysaccharides. Genomic strategies could also be used to obtain a further enhancement of the adsorption/non-adsorption activity of wine yeasts. Based on winemaking requirements and on parietal adsorption activity, a specific selection of yeasts might be performed: (a) to protect wine colour during red winemaking, (b) to remove residual wine colour during white winemaking, (c) to selectively remove ochratoxin A, and (d) to protect phenolic compounds responsible for antioxidant activity.