DNA barcoding reveals fraudulent substitutions in shark seafood products: The Italian case of “palombo” (Mustelus spp.)

In food safety and traceability, consumers are more and more demanding about composition and provenance of processed seafood products. In the trade of many species, manufacturing alterations usually bring to the loss of any morphological diagnostic features of the species, enhancing the possibility of fraudulent substitutions and incorrect product labeling. In this study, we used a DNA barcoding approach to identify species substitutions cases in shark slices sold in Italy under the vernacular name of “palombo” (that is referred to the triakiids Mustelus mustelus and Mustelus asterias for the Italian regulation). We produced the coxI barcode sequence (550 bp long) for all the analysed specimens, and we compared them with reference sequences from different databases (GenBank and BOLD), using two bioinformatic identification methods, one of them developed in our laboratory. Results showed a high amount of commercial frauds rising the 80% of analysed “palombo” slices and highlighting a relevant economical impact for consumers.     

Suppressive effect of Tetragenococcus halophilus,isolated from fish-nukazuke,on histamine accumulation in salted and fermented fish

Occasionally, quantities higher than 1000 mg/kg of histamine (Hm) accumulate in salted and fermented fish products by the histidine decarboxylase of halophilic lactococci Tetragenococcus sp. In a total of 200 isolates from fish nukazuke (salted and fermented fish with rice bran), 13 strains produced Hm more than 200 μg/ml in 0.5% histidine containing broth, whereas 130 isolates produced absolutely no Hm. Among the strains, 22 strains suppressed the Hm production of the Hm-forming (HmF) strains. Both the HmF and Hm-suppressing (HmS) strains were identified as Tetragenococcus halophilus. To observe the Hm-suppressing effect, a specified quantity of live cells was needed. In the case of 10% NaCl salted sardine, inoculation with 3 log cells/g of a strain HmF-131 resulted in a significant Hm accumulation, 2800 μg/g in 30 days at 20 °C. The increase in Hm was clearly suppressed by 9 log live cells/g of strain HmS-129. These results suggest that HmS-129 can be used as a starter for salted and fermented fish products, enhancing food safety.     

DNA barcoding reveals high substitution rate and mislabeling in croaker fillets (Sciaenidae) marketed in Brazil: The case of “pescada branca” (Cynoscion leiarchus and Plagioscion squamosissimus)

The removal of morphological features during fish processing hinders identification to the species level, increasing the chances of species substitution and the mislabeling of marketed products. We used DNA barcoding to assess whether species substitutions occur in croaker (Sciaenidae) fillets labeled as “pescada branca” sold in the Brazilian Amazon, where two species are known under this vernacular name (Cynoscion leiarchus and Plagioscion squamosissimus). A 577-bp cytochrome C oxidase subunit I (COI) sequence was obtained from 137 fillets and compared with the sequences of whole Sciaenidae fish that were identified based on their morphology and the reference sequences of the BOLD and GenBank public databases. DNA barcoding was able to identify 90% of the samples analyzed to the species level, and the results showed a high rate of species substitution in the fillets labeled as “pescada branca”. The substitution rate was 100% if using the criterion that the fillets should be C. leiarchus and 76.6% if using the criterion that they should be P. squamosissimus. Additionally, the results show that “pescada branca” was replaced in most cases by species of lower commercial value, which clearly demonstrates economic fraud aimed at increased profits. Our data confirm that DNA barcoding is a sensitive and reliable tool that can be applied to authenticate processed fish.     

Comparative Studies of Ginger (Zingiber officinale) and West African Black Pepper (Piper guineense) Extracts at Different Concentrations on the Microbial Quality of Soymilk and Kunun-zaki

Extracts of two spices, namely ginger (Zingiber officinale) and black pepper (Piper guineense) were prepared in 0.4%, 1.2%, 2.4% and 3.6% concentrations. Soymilk and kunun-zaki were treated respectively with the different concentrations and stored at ambient temperature for 5 days. The microbial load and identification were determined every day of storage until samples were adjudged spoilt.On the first day, 0.4% ginger extract in soymilk and kunun-zaki had a microbial load of 7.77 × 10^6b and 5.17 × 10^6b respectively. 3.6% ginger extract in soymilk and kunun-zaki recorded 3.73 × 10^6b and 3.30 × 106 each. 0.4% black pepper extract in soymilk had 6.273 × 10^6b and recorded 4.63 × 10^6b in kunun-zaki. 3.6% black pepper extract in soymilk and kunun-zaki had a microbial load of 3.20 × 10^6d and 2.90 × 10^6c respectively. On the third day the microbial load increased for both ginger and black pepper extract. Ginger extract recorded 9.13 × 10^6b in soymilk and 5.60 × 10^6b in kunun-zaki at 0.4% concentration. Black pepper extracts recorded 7.43 × 10^6b in soymilk and 3.27 × 10^6b in kunun-zaki also at 0.4% extract. 3.6% black pepper extract recorded 4.10 × 10^6a in soymilk and 2.20 × 106c in kunun-zaki.There was linear reduction of microbial load as spice concentration increased. Black pepper recorded lower microbial load, thus having more antimicrobial activity and may be preferred to be used as natural antimicrobial preservatives to extend the shelf-life of food.     

Mechanical separation process for the value enhancement of Atlantic horse mackerel (Trachurus trachurus), a discard fish

Mechanically separated meat (MSM) is the product obtained by removing meat from bones by pressure application. Whole fillets and fish burgers from minced muscle and from mechanical separation of Atlantic horse mackerel (Trachurus trachurus) were evaluated immediately after processing (T₀) and after 90 days of storage at − 20 °C for parameters related to quality loss. Firstly, mechanical separation inhibited water losses (2.67% against 4.57 and 5.57% in whole fillets and burgers from minced muscle, respectively), but the colour of MSM was duller and redder than the samples from other groups. Horse mackerel contained low fat (< 1 g/100 g muscle), and high PUFAω3 content (around 57 g/100 g total fatty acids), especially EPA and DHA (around 52 g/100 g) regardless the treatment. However, the species was susceptible to oxidation, as revealed by the high TBARS content at T₀ (> 8 mg MDA-eq/100 g muscle). Nevertheless, Atlantic horse mackerel showed a high antioxidant capacity (ABTS, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid, DPPH, 2,2-diphenyl-1-picrylhydrazyl, and FRAP, ferric-reducing ability) at T₀ which may protect muscle against oxidative damages both during processing treatment and storage.Industrial relevanceThe mechanical separation process described in the article has been largely utilized for terrestrial animal products. However, it is seldom adopted by fish industry, especially for recovering discard fish species. Horse mackerel is an underutilized species, normally transformed into animal feed despite its high levels of omega-3 polyunsaturated fatty acids. Therefore this study was conducted in order to determine the effect of a mechanical separation technique on the physicochemical properties of horse mackerel. Our study showed that, although this species is susceptible to oxidative changes, mechanically separate meat can be a high-quality ingredient in burgers, nuggets, sticks, or even sauces which may represent a way for the valorisation of discard species.     

Assessment of high intensity ultrasound for surface decontamination of salmon (S. salar), mackerel (S. scombrus), cod (G. morhua) and hake (M. merluccius) fillets,and its impact on fish quality

The effect of applying high intensity ultrasound on microbiological and quality parameters in several fish species was assessed at laboratory scale. Samples of salmon (S. salar) and mackerel (S. scombrus) as oily fish, and cod (G. morhua) and hake (M. merluccius) as white fish, were treated using an ultrasonic bath (30 kHz). Samples of each species were separated into three groups (i) untreated control (C), (ii) water immersion only (IM) and (iii) ultrasound (US) and treated for 5, 15, 25, 35 and 45 min. All physicochemical parameters were determined in samples treated for 45 min. Microbiological counts were reduced significantly (p < 0.05) after US treatment in oily fish species with reductions of up to 1.5 & 1.1 log CFU/g for psychrophilic and mesophilic viable counts (PVC & TVC) observed in salmon and mackerel respectively. Corresponding reductions in white fish species were only 0.5 log CFU/g. Lipid content did not change significantly (p > 0.05) after treatment. Significant reductions of thiobarbituric acid reactive substances (TBARS) values (C: 0.36; US: 0.18) and colour changes were observed in salmon (a* C: 12.8; US: 10.0). Moisture levels increased by 8% following US treatment in hake.     

Shelf-life extension of herring (Clupea harengus) using in-package atmospheric plasma technology

Atmospheric cold plasma is a green and emerging technology, highly interesting to the food industry for its application. Dielectric Barrier Discharges (DBD) can generate atmospheric cold plasma inside sealed packages filled with air through the use of high voltages. This study investigated the use of a large gap DBD design to generate a plasma discharge within the headspace of packaged herring fillets, and its effects on microbiological and quality markers of the fish stored for 11 days at 4 °C. DBD plasma treatment conditions were 70 kV or 80 kV for 5 min treatment time.Results showed that the microbial load (total aerobic mesophilic, total aerobic psychrotrophics, Pseudomonas, lactic acid bacteria and Enterobacteriaceae) were significantly (p < 0.05) lower in the treated samples compared to the control samples. However, samples exposed to the lowest applied voltage better retained key quality factors (lower oxidation and less colour modification). DBD-treatment caused a reduction in trapped water in the myofibrillar network (T21), identified using low-field nuclear magnetic resonance of protons (¹H LF NMR).The results indicate that in-package plasma treatment could be employed as an effective treatment for reducing spoilage bacteria in fish.Industrial relevanceDielectric Barrier Discharge (DBD) was evaluated as a treatment for highly perishable fish products. DBD's is a safety and lower costs alternative for processing industry. DBD has been scarcely tested on fish; this work showed results on quality and shelf-life of a highly perishable fish species, which might serve as reference for processing optimisation of fish products minimally processed by DBD.     

Microbial and endogenous origin of fibrinolytic activity in traditional fermented foods of Northeast India

Traditional fermented foods of Northeast India and their associated microorganisms were studied for fibrinolytic activity. A simple and reliable spectrophotometric method to quantify fibrinolytic activity in comparison to conventional fibrin plate assay was established. Out of 31 different types of fermented foods screened, protein rich fermented foods mostly soybean and fish products possessed fibrinolytic activity. Higher fibrinolytic activity was observed in fermented small cyprid fish (Puntius sophore Ham.) products than fermented soybean products. Fibrin zymogram based cluster analysis indicated fibrinolytic activity of endogenous origin in fermented fish products and microbial origin in fermented soybean products. A fermented soybean product Hawaijar showed higher specificity towards fibrin as indicated by fibrinolytic to caseinolytic activity ratio of 3.8 ± 0.21. Identification of 85 fibrinolytic isolates by amplified ribosomal DNA restriction analysis and ribosomal DNA sequencing yielded 15 phylotypes, of which 55% were Bacillus species. Lactic acid bacteria with fibrinolytic activity namely Vagococcus carniphilus, Vagococcus lutrae, Enterococcus faecalis, Enterococcus faecium, Enterococcus gallinarum and Pediococcus acidilactici were identified. Bacillus subtilis, Bacillus amyloliquefaciens, V. carniphilus, V. lutrae and Proteus mirabilis were promising producers of fibrinolytic enzymes with more than 350 plasmin units/mL. The high population of fibrinolytic P. mirabilis found in fermented soybean and pork products might be a serious health concern. Fibrinolytic activity found in fermented food could be partially dependent on the isolated microbes. PCR-DGGE analysis detected uncultivated proteolytic bacteria in both raw material and fermented fish products. These fibrinolytic foods and associated microbial resources could be further explored for novel fibrinolytic therapy.     

Mercury speciation in the muscle of two commercially important fish,hake (Merluccius merluccius) and striped mullet (Mullus barbatus) from the Mediterranean sea: estimated weekly intake

Total mercury and methylmercury concentrations were measured in the muscle tissue of two fish species from the Ionian and Adriatic seas. Higher total mercury and methylmercury concentrations were detected in striped mullet (Mullus barbatus), a benthic species (Ionian sea: Hg=0.40 μg g⁻¹ wet wt, MeHg=0.40 μg g⁻¹ wet wt; Adriatic sea: Hg=0.49 μg g⁻¹ wet wt, MeHg=0.44 μg g⁻¹ wet wt), than in hake (Merluccius merluccius), a pelagic species (Ionian sea: Hg=0.09 μg g⁻¹ wet wt, MeHg=0.09 μg g⁻¹ wet wt; Adriatic sea: Hg=0.18 μg g⁻¹ wet wt; MeHg=0.16 μg g⁻¹ wet wt). Total mercury residues were determined in all samples of both species from the Adriatic sea, while levels below the limit of detection were registered in 25% and 11%, respectively, of striped mullet and hake samples from the Ionian sea. In 18.8% and 22.2% of striped mullet samples from the Ionian and Adriatic seas, respectively, total mercury concentrations exceeded the maximum level fixed by the European Commission Decision (Hg=0.5 μg g⁻¹ wet wt). In the two different species, mercury was present almost completely in the methylated form with mean percentages between 60% and 100%. The estimated weekly intake for total mercury was below the established the provisional tolerable weekly intake (PTWI) for both species, though their consumption provides a methylmercury intake above the WHO safety limit.     

Study of lipoxygenase and peroxidase as blanching indicator enzymes in peas: change of enzyme activity,ascorbic acid and chlorophylls during frozen storage

In this study, the effects of different blanching conditions on residual lipoxygenase (LOX) and peroxidase (POD) activities and quality changes in peas during frozen storage were studied. Peas were analysed for LOX and POD activities, ascorbic acid and chlorophylls a and b contents at 1, 2, 3, 6, 9 and 12 months of frozen storage. No regeneration of LOX and POD activities was determined in frozen-stored peas at −18 °C. The degradations of ascorbic acid and chlorophylls followed first-order kinetics. The half-lives of ascorbic acid, chlorophylls a and b derivatives in unblanched peas were found to be 3.30, 14.01 and 36.76 months during storage, respectively. Blanching at both 70 °C for 4.0 min and 80 °C for 2.0 min increased the half-life of ascorbic acid while it decreased those of chlorophylls a and b. Overall results suggested a blanching time of 2.0 min at 80 °C to inactivate 90% of initial POD activity, so, to retain quality parameters such as ascorbic acid and chlorophyll pigments in a storage period of 12 months at −18 °C.     

Total polyphenols,catechin profiles and antioxidant activity of tea products from purple leaf coloured tea cultivars

Black (aerated) and green (unaerated) tea products, processed from 10 green and 18 purple leaf coloured cultivars of Kenyan origin, and two tea products, from the Japanese cultivars, Yabukita and Yutakamidori, were assayed for total polyphenols (TP) content, individual catechin profiles and in vitro antioxidant capacity (AA). In addition, the phenolic content of the tea products was determined using the Folin–Ciocalteu phenol reagent. Catechin fractions were identified using reverse phase high performance liquid chromatography (HPLC) with a binary gradient elution system.The AA% of the tea products was determined using a 2,2′-diphenyl picrylhydrazyl (DPPH) radical assay method. The results showed that TPs, catechin profiles and antioxidant activities were significantly (p ? 0.05) higher in unaerated than in aerated teas. Tea products from the purple leaf coloured tea cultivars had levels of TPs, total catechin (TC) and antioxidant activities similar to those from the green leaf coloured cultivars, except for teas from the Japanese cultivars that were very low in the assayed parameters. Caffeine content was significantly (p ? 0.05) lower in products from the purple leaf coloured cultivars than in those from the green leaf coloured tea cultivars. Antioxidant activity (%) was higher in tea products from the Kenyan germplasm than in those from the Japanese cultivars. Antioxidant potency of tea products was significantly (r = 0.789⁷, p ? 0.01) influenced by the total anthocyanin content of the purple leaf coloured cultivars. Cyanidin-3-O-glucoside was the anthocyanin most highly correlated with AA% (r = 0.843⁷, p ? 0.01 in unaerated tea). Total catechins in the unaerated products from the green leaf coloured tea cultivars were also significantly correlated with antioxidant capacity (r = 0.818⁷, p ? 0.01). Results from this study suggest that the antioxidant potency of teas is dependent on the predominant flavonoid compound, the type of tea cultivar and the processing method.     

Effects of chitosan-based coating and modified atmosphere packaging (MAP) on browning and shelf life of fresh-cut lotus root (Nelumbo nucifera Gaerth)

The present study investigated the effect of chitosan coating containing antibrowning agents and modified atmosphere packaging (MAP) on the browning and shelf life of fresh-cut lotus root stored at 4 °C for 10 days. The atmosphere in the packages was evaluated for O₂ and CO₂ concentrations. The browning on the surface of lotus root slices was prevented by chitosan-based coating and MAP treatment. L* values of coated + MAP and control samples were 68.8 and 48.9 after 8 days storage, respectively. For a^? and b^? values, samples of coated + MAP treatment had the slowest increasing trends among all the treatments. At the end of storage, the coated + MAP samples exhibited the lowest polyphenol oxidase (PPO) activity and malondialdehyde (MDA) content. Its highest overall visual quality (OVQ) scores (> 7) demonstrated that chitosan-based coating + MAP treatment could provide a better inhibitory effect on the browning and extend the shelf life of fresh-cut lotus root.Industrial relevance: Fresh-cut vegetables have drawn the attention of industry as a novel lightly processed product. Both edible coating and MAP treatment cause changes in atmosphere composition and respiration rate of lotus root slices. This combined treatment could be used to control the browning and improve the storage life of this fresh-cut vegetable. This information could be useful for the development of novel application to edible coating and MAP design for lightly processed lotus root.     

Sensory profiles and consumer acceptability of a range of sugar-reduced products on the UK market

Current UK intake of non-milk extrinsic sugars (NMES) is above recommendations. Reducing the sugar content of processed high sugar foods through reformulation is one option for reducing consumption of NMES at a population level. However, reformulation can alter the sensory attributes of food products and influence consumer liking. This study evaluated consumer acceptance of a selection of products that are commercially-available in the UK; these included regular and sugar-reduced baked beans, strawberry jam, milk chocolate, cola and cranberry & raspberry juice. Sweeteners were present in the reformulated chocolate (maltitol), cola (aspartame and acesulfame-K) and juice (sucralose) samples. Healthy, non-smoking consumers (n = 116; 55 men, 61 women, age: 33 ± 9 years; BMI: 25.7 ± 4.6 kg/m²) rated the products for overall liking and on liking of appearance, flavor and texture using a nine-point hedonic scale. There were significant differences between standard and reduced sugar products in consumers' overall liking and on liking of each modality (appearance, flavor and texture; all P < 0.0001). For overall liking, only the regular beans and cola were significantly more liked than their reformulated counterparts (P < 0.0001). Cluster analysis identified three consumer clusters that were representative of different patterns of consumer liking. For the largest cluster (cluster 3: 45%), there was a significant difference in mean liking scores across all products, except jam. Differences in liking were predominantly driven by sweet taste in 2 out of 3 clusters. The current research has demonstrated that a high proportion of consumers prefer conventional products over sugar-reduced products across a wide range of product types (45%) or across selected products (27%), when tasted unbranded, and so there is room for further optimization of commercial reduced sugar products that were evaluated in the current study. Future work should evaluate strategies to facilitate compliance to dietary recommendations on NMES and free sugars, such as the impact of sugar-reduced food exposure on their acceptance.     

Gamma irradiation as a practical alternative to preserve the chemical and bioactive wholesomeness of widely used aromatic plants

Aromatic plants require effective conservation technologies to expand their use. Irradiation might ensure plant decontamination, while maintaining their chemical, organoleptic, nutritional and bioactive qualities. In this study, the effects of gamma irradiation (1 and 10 kGy) in chemical, nutritional and antioxidant properties of Aloysia citrodora, Melissa officinalis, Melittis melissophyllum and Mentha piperita were evaluated. Gamma irradiation (up to 10 kGy) caused some statistically significant changes. However, when analyzed under an integrated approach, unirradiated and irradiated samples were grouped indiscriminately, indicating that irradiation treatment did not cause sufficient changes to define a specific chemical profile. Interestingly, each species was differentially affected by irradiation treatment. Overall, it might be considered that gamma irradiation (up to 10 kGy) is a feasible conservation technology for the assayed Lamiaceae and Verbenaceae species. This is an interesting result because the 10 kGy dose guarantees disinfested and decontaminated samples.     

A new,simple method for the production of meat-curing pigment under optimised conditions using response surface methodology

The production of cured meat pigment using nitrite and ascorbate in acidic conditions was evaluated. HCl, ascorbate and nitrite concentrations were optimised at three levels using the response surface method (RSM). The effects of process variables on the nitrosoheme yield, the wavelength of maximum absorbance (λ_max), and L*, a* and b* values were evaluated. The response surface equations indicate that variables exerted a significant effect on all dependent factors. The optimum combinations for the reaction were HCl = − 0.8, ascorbate = 0.46 and nitrite = 1.00 as coded values for conversion of 1 mM hemin to nitrosoheme, by which a pigment yield of 100%, which was similar to the predicted value of 99.5%, was obtained. Likewise, the other parameters were not significantly different from predicted values as the λ_max, L*, a* and b* values were 558 nm, 47.03, 45.17 and 17.20, respectively. The structure of the pigment was identified using FTIR and ESI/MS.     

Effects of high hydrostatic pressure and high temperature short time on antioxidant activity,antioxidant compounds and color of mango nectars

High hydrostatic pressure (HHP, 600 MPa/1 min) and high temperature short time (HTST, 110 °C/8.6 s) treatments of mango nectars were comparatively evaluated by examining their effects on antioxidant activity, antioxidant compounds, color, and browning degree (BD) immediately after treatments and during storage of 16 weeks at 4 and 25 °C. Steam blanching was used prior to HHP and HTST to inactive endogenous enzymes. Results showed that antioxidant capacity (FRAP assay), L-ascorbic acid, sodium erythorbate, total phenols, total carotenoids, the redness (a*), the yellowness (b*), and BD changed insignificant after HHP or HTST treatment. The lightness (L*) exhibited a significant decrease in HTST-treated mango nectars, while no significant changes in HHP-treated samples. After 16 weeks storage at 4 and 25 °C, there were significant changes in antioxidant activity, antioxidant compounds, color, and BD of mango nectars, whereas differences between HHP- and HTST-treated samples were not significant except for the decrease in L-ascorbic acid and sodium erythorbate, which was more pronounced in HHP-treated samples. Kinetic data of changes in L-ascorbic acid, sodium erythorbate, total phenols, and total carotenoids during storage fitted well into a combined model for both HHP- and HTST-treated samples.Industrial relevanceMango (Mangifera indica L.) is one of the important tropical fruits, and its processed products are of high commercial and economic importance. This research paper presents a comparison on HHP- and HTST-treated mango nectars, and also provides information about storage stability of antioxidant activity, antioxidant compounds, and color of mango nectars. The available data would provide technical support for the evaluation and application of HHP or HTST in the mango nectar industry, and also for the establishment of criteria for commercial production of high quality mango nectars with safety requirements.     

Assessment of the bioavailability of toxic and non-toxic arsenic species in seafood samples

Bioavailability of total arsenic, toxic (arsenite, As(III); and arsenate, As(V)), and non-toxic (monomethylarsonic acid, MA; dimethylarsonic acid, DMA; arsenobetaine, AB; and arsenocholine, AC) arsenic species has been assessed in different raw seafood samples (white fish, cold water fish and molluscs) by using an in vitro model that combines simulated gastric and intestinal digestion/dialysis methods. Correlations between arsenic species bioavailability and seafood nutrient contents (fat and protein) have also been established. Total arsenic content in seafood samples, and dialyzable and non-dialyzable fractions, were analyzed by inductively coupled plasma – mass spectrometry (ICP–MS) after a microwave-assisted acid digestion treatment. The determination of the different arsenic species concentrations in the samples (after an optimised matrix solid phase dispersion (MSPD) approach) and in the dialyzable fraction was done by high performance liquid chromatography (HPLC) coupled to ICP-MS as a selective detector. Accuracy of the procedure (total arsenic determination) was assessed by analyzing DORM-2 and BCR-627 certified reference materials. The accuracy of the in vitro procedure was established through a mass-balance study. After statistical evaluation (95% confidence interval), good accuracy of the whole in vitro process, for total arsenic and for arsenic speciation, was observed. High dialyzability percentages for total arsenic and for arsenic species were found (i.e. from 84.6 ± 1.7% to 106 ± 2.6%). Bioavailability of arsenic exhibits a negative correlation with the fat content of the seafood. However, no correlation was observed between the bioavailable fraction of total arsenic and arsenic species and the protein content of the seafood studied.     

A comparison of the proximate compositions and fatty acid profiles of zander (Sander lucioperca) from two different regions and climatic conditions

The proximate compositions and fatty acid profiles of the flesh of the fresh water fish zander (Sander lucioperca) obtained from Eğirdir Lake and from Seyhan Dam Lake were compared. The crude protein (18.8–18.1%), ash (1.37–0.75), and dry matter (20.67–20.09) contents of fish in Seyhan Dam Lake were observed to be higher than those in the other lake. Zander in Seyhan Dam Lake had a significantly (p < 0.05) higher lipid content than its Eğirdir counterpart. Differences were also observed in the fatty acid profiles. The percentages of total saturated fatty acids (SFA) and total monounsaturated fatty acids (MUFA) were higher in the zander in Seyhan Dam Lake than in Eğirdir Lake, whereas the corresponding total polyunsaturated fatty acids (PUFA) content was lower. Moreover, the fatty acid composition of these fish showed a relatively high ratio of PUFA/SFA (1.00). Both zanders showed palmitic acid, C16:0, to be predominant, (19.6–20.8%), followed by oleic acid, C 18:1 n − 9, (19.2–13.4%).The data obtained indicate that the % composition of n − 3 PUFAs is greater in the flesh of zander in Eğirdir Lake. This finding is in compliance with the fact that n − 3 fatty acids in fish living in cold climatic conditions have a higher % composition. It was concluded that the consumption of zander, widely found in Eğirdir Lake and having higher % composition of n − 3 PUFAs than those caught from Seyhan Dam Lake, is more beneficial for human health.     

Simultaneous detection and enumeration of viable lactic acid bacteria and bifidobacteria in fermented milk by using propidium monoazide and real-time PCR

This study describes a procedure that allows specific detection and enumeration of viable bacteria in four species of lactic acid bacteria (Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus casei subsp. casei and Lactobacillus acidophilus) and of Bifidobacterium lactis, mixed in fermented milk products. The procedure is based on the combined use of propidium monoazide (PMA), able to distinguish between viable and irreversibly damaged cells, with species-specific quantitative real-time PCR (RTi-PCR). Loss of viability of the species in a fermented milk through storage at 4 °C was similarly (P < 0.05) detected by PMA–RTi-PCR and selective plate counts. Furthermore, comparison of results obtained by both methods showed a Pearson linear correlation of 0.995. The enumeration of viable bacteria by PMA–RTi-PCR could be performed in 3 h, whereas enumeration by selective plate counts required three days. The procedure developed is a fast method for the identification, enumeration and discrimination of viability of lactic acid bacteria and bifidobacteria mixed in fermented milk products.     

Acting to self-regulate unhealthy eating habits. An investigation into the effects of habit,hedonic hunger and self-regulation on sugar consumption from confectionery foods

Many people are motivated to eat healthily but find it difficult to override established and less healthy habits. Habits by their nature are unconscious and cued by the environment, thus making them powerful determinants of behaviour. Limited research has explored the role of habit as a mediator between self-regulation and sugar consumption. This study investigated the relative importance of factors that support/impede the consumption of foods with high sugar content and the mediating effect of habit. The study sample was 500 Irish adult’s representative of the population. Sugar consumption, habit, hedonic hunger, self-efficacy, perceived need, dietary planning and dietary self-monitoring were assessed using self-reported measures. A path analysis of the data was used to test the direct and indirect effects of the independent factors on estimated sugar consumption grams per day (g/d). In addition, the interaction effects of self-efficacy and dietary planning/self-monitoring on sugar consumption was examined using simple slope analysis. The results showed that habit had the largest effect in the model and was positively related to sugar consumption g/d (b = 12.09, p < 0.01). While the direct effect of self-efficacy on sugar-consumption g/d was significant (b = −5.25, p < 0.05), this effect was partially mediated by habit (−4.84, Bca CI −7.00, −3.00) and the direct effect of action control on sugar consumption (b = −1.30, p = 0.311) was fully mediated by habit (b = −2.42, Bca CI −3.93, −1.20), which indicates that strong unhealthy habits compete against self-efficacy and can reduce the potential benefits of dietary planning and self-monitoring. The simple slope analysis revealed that action control has a significant negative effect on sugar intake when self-efficacy is weak (b = −5.48, p = 0.01). The direct effect of hedonic hunger on confectionery sugar consumption (b = 1.38, p = 0.376) was fully mediated by habit (b = 5.92, Bca CI 4.20, 8.08) indicating that the desire to eat tempting food may overrides one’s intended behaviour resulting in counter-intentional habits. It is apparent from the findings that a dual strategy of targeting behaviour and the underlying habits may be effective in improving dietary intake and self-regulation is likely to be sustainable only in an environment that facilitates healthy eating behaviour.