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21.
The effect of including distilled rosemary leaf in the diet of pregnant ewes on subsequent lamb meat quality was studied. Thirty-six Segureña ewes were randomly assigned to three homogeneous groups. One group was fed a basal diet (BD) as control while the diet of the other two groups was modified by substituting 10% (R1) and 20% (R2) of the BD with a pellet made from 50% barley and 50% of distilled rosemary leaves (DRL). Meat spoilage (TVC, PSY and MYC), TBARS, CIELab coordinates and the sensory characteristics contribution of fresh lamb meat packed in MAP (70% O2:30% CO2) were analyzed on days 0, 7, 14 and 21. In general, R1 and R2 had higher a* values, better scores for meat and fat colour (P < 0.05) and lower TBARS and rancid odour (P < 0.05), than the control samples. The total viable count was lower in meat DRL. No statistically significant differences were detected between the two treatments (10–20% DRL).  相似文献   
22.
The aim of this research was to evaluate changes in the phenolic compounds, isoflavones and antioxidant activity of soymilk following in vitro gastrointestinal digestion (including dialysis). Gastric digestion significantly influenced the release of bioactive substances from the soymilk matrix, increasing the concentration of total phenolic components (35% as the sum of individuals and 14% by Folin–Ciocalteu [F–C] method), total isoflavone content (22%) and total antioxidant activity (76%). The concentration of all those compounds was reduced significantly in the duodenal fraction in comparison to gastric digestion and their lowest concentration was observed in the dialysed fraction, where phenolic acids were not detected. The bioaccessibility of soymilk phenolic compounds was 15% as the sum of individuals and 20% by F–C assay; isoflavones 36% and constituents with antioxidant activity 27%. Results suggest that most of these compounds were sufficiently available to be absorbed and could contribute health benefits.  相似文献   
23.
This study provides innovative information on the influence of new technologies of ageing (stainless steel tanks with wood staves or wood tablets of chestnut or Limousin oak), in comparison with traditional technology (oak wooden barrels), on the extraction/oxidation kinetics of low molecular weight compounds of wine brandy. The brandy was sampled and analysed by HPLC during the first year of ageing. The results show that most of the compounds tend to increase over the time, but their extraction/oxidation kinetics depend on the ageing technology. The wooden barrels promote greater enrichment in the majority of the compounds. However, gallic acid, ellagic acid and syringaldehyde, and vanillin and 5-methylfurfural, which are strong antioxidants and key-odourant compounds, respectively, present higher contents in the brandy aged with the alternative technologies. Chestnut proves to be a suitable alternative to Limousin oak for the ageing of brandy in all the studied technologies, inducing faster evolution and high quality.  相似文献   
24.
Juices prepared from arils of ‘Mollar’ pomegranates were analysed for naturally occurring microorganisms, CIE Lab colour parameters, total phenols, anthocyanins and punicalagins, ellagic acid content and antioxidant capacity before and after low-, mild- and high-temperature pasteurisations (LTPs, MTPs and HTPs): 65, 80 and 90 °C for 30 or 60 s. Mean aerobic plate count (APC), yeast and mold count (YMC), and lactic acid bacteria (LAB) for fresh juices were 5.7, 5.36 and 4.0 log CFU/mL, respectively. MTPs and HTPs were sufficiently effective to decrease APCs to nil or negligible levels. An increase in CIE a values and decrease in CIE b values were the characteristic colour changes in heat-treated juices. The effect of pasteurisations showed that total phenols, punicalagins and ellagic acid were not much affected by thermal processing. Total anthocyanin content and antioxidant capacity were substantially and significantly influenced by the heat treatment applied. A linear relationship was observed between Trolox equivalent antioxidant capacity (TEAC) values and total anthocyanins, suggesting that they contributed strongly to the antioxidant capacity of pomegranate juice.  相似文献   
25.
The present research focused on the biogenic amines (BAs) formation in skipjack tuna (Katsuwonus pelamis) throughout the whole canning process. In agreement with its wide employment on this species, on‐board brine immersion freezing (BIF) was tested as post‐mortem processing. The study included fish samples corresponding to different stages of the canning process such as frozen, thawed, cooked and canned; after cooking, two kinds of tuna muscles were considered, that is, whole fillets (main product) and grated muscle (off‐product arising from small pieces). For the BAs (tryptamine, putrescine, cadaverine, histamine, spermidine and spermine) assessment, an HPLC‐DAD method was developed and validated in skipjack tuna samples, in agreement with different parameters such as suitability, linearity, limits of detection and quantification, precision, accuracy and robustness. Tuna submitted on‐board to BIF procedure provided low levels of spermine and spermidine (up to 27.6 mg kg?1), while contents on the remaining BAs maintained below the limit of detection. Throughout the different stages of the canning process, skipjack tuna showed a low formation of most BAs; interestingly, histamine content was found below 10.6 mg kg?1 level. The highest values were obtained for spermidine, these related to cooked grated tuna (from 22.6 to 66.7 mg kg?1) and canned grated tuna (from 70.6 to 104.4 mg kg?1). Values for pH assessment in all kinds of tuna samples corroborated the results obtained for BAs determination. BIF procedure proved to be an amenable post‐mortem processing to guarantee the quality of canned skipjack tuna.  相似文献   
26.
The presence of pathogens such as Escherichia coli O157:H7 (EC) represents risks to public health and to economy of Brazilian beef industry. In this context, the application of lactic acid (LA) is an efficient practice employed to reduce bacterial count without compromising consumer safety. Our aim was to verify the inhibitory effect of LA application combined with aging and different packaging on EC and its effects on beef color. The LA effect on EC counts was concentration dependent during aging and storage, with T2 (10% of LA added) demonstrating greater (p < .05) reductions than T1 (5% of LA added). Aging did not affect (p > .05) EC counts, however reduced (p < .05) the total aerobic mesophilic bacteria. LA application promoted a decrease on beef redness (p > .05) after application and during storage. LA treatment (T2) promoted a reduction in E. coli O157:H7, despite the effects on beef color.

Practical applications

The present data evidence a breakthrough in lactic acid (LA) researches once evaluate the inhibitory effect of aging, LA concentration and package on Escherichia coli O157:H7 and the influence of these technologies in beef color. Moreover, the data presented allow clarifying the meat industry about the potential use of LA preservation on beef.  相似文献   
27.
High planting density has been used to increase coffee production but there are few studies related to the variations it provokes in metabolite compositions. The use of 1H NMR data associated with chemometric techniques allows the determination of metabolic fingerprints and verification of metabolic changes when coffee is subjected to high planting densities. The aim of this work is to investigate 1H NMR spectral data of green bean extracts of Coffea arabica cv. IAPAR 59 grown in a square pattern at two planting densities, 6000 and 10,000 plants ha?1. Thirty extracts were obtained using a simplex centroid design with four solvents (ethanol, acetone, dichloromethane, and hexane). The lyophilized extracts were dissolved in DMSO-d6 to obtain the 1H NMR spectra. The spectral data were analyzed with principal component (PCA) and cluster analyses (CA). Significant differences between ethanolic and non-ethanolic extracts were found by PCA. Only the ethanolic mean spectrum showed characteristic chemical shifts of sugars and trigonelline. Acetone extracts were separated by cluster analysis.  相似文献   
28.
The aim was to study spoilage during the refrigerated storage of cooked pork loin processed by the sous vide method. Samples were packaged under vacuum into polyamide-polypropylene pouches, cooked at an oven temperature/time of 70 °C/12 h, chilled at 3 °C and stored at 2 °C for 0, 5 or 10 weeks. Microbial (psychrotrophs, lactic acid bacteria, Enterobacteriaceae, moulds and yeasts), physical–chemical (pH, water activity, TBARS, acidity, L*a*b* colour, texture profile analysis and shear force) and sensory (appearance, odour, flavour, texture and acceptance) parameters were determined. The results showed that sensory spoilage preceded microbiological spoilage of sous vide pork loin. Counts bellow 1 log cfu/g of psychrotrophs, anaerobic psychrotrophs, Enterobacteriaceae and lactic acid bacteria were detected in any control week, while moderate counts (2–3 log cfu/g) of moulds and yeasts were found. Minor changes in water activity, lipid oxidation, CIELab colour, hardness, cohesiveness or gumminess were associated with spoilage of pork loin, only decreases of lactic acid, springiness and shear force were observed. The pork loin was unacceptable after 10 weeks. This loss of acceptance was mainly due to the deterioration of meaty flavour and odour, although the loss of appearance, juiciness and firmness also contributed. Moderate warmed-over and rancidity were detected. The sensory analysis was the most effective method for determining the shelf life of the sous vide pork-based dishes.  相似文献   
29.
30.
Characteristics of sheep milk are of great interest for the dairy industry, as almost the totality of production is intended for cheesemaking. However, the existing relationships between these variables are complex. This study assessed composition, hygienic quality, coagulation properties, and curd yield of 1,200 individual Manchega sheep milk samples. The aim was to compare the effect of composition and hygienic quality on coagulation and curdling, and to evaluate the relationship between curd yields and the coagulation process and the effect of other features by using path analysis methodologies. Outcomes proved path analysis to be a useful and effective tool to assess these relationships through direct and indirect paths within the same model. Results showed that the factors that had a direct influence on milk coagulation were lactose concentration, casein content, and initial pH of milk. Contrastingly, somatic cells did not seem to have any effect (direct or indirect) on the coagulation process. Factors that directly affected curd yield were fat content, lactose concentration, casein content, and curd moisture. However, technological parameters showed little effect over curd yield.  相似文献   
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