254 research outputs found
Analysis of the water soluble compounds as a tool for discriminating traditional and industrial high moisture mozzarella made with citric acid
High moisture mozzarella from cow milk is a pasta filata cheese that can be manufactured by different protocols. Fermentation by autochthonous starter is used for the traditional product, whereas direct acidification with citric acid is widely used at industrial level. Both types are stored immersed in a liquid for preserving freshness, but this packaging method is known to favour the changes of the quality characteristics. The present study aimed to assess the evolution of the soluble compounds and to evaluate their use as chemical indices for discriminating the two types of mozzarella. The contents of lactose, organic acids, water soluble nitrogen and free aminoacids differently changed over time. The whole patterns of these soluble compounds allowed discrimination of the two products during the whole storage period. The simple analyses of lactic acid and lactose could be a rapid tool to protect traditional mozzarella from industrial imitations obtained with citric acid
Cheese ripening in nonconventional conditions: A multiparameter study applied to Protected Geographical Indication Canestrato di Moliterno cheese
A multiparameter study was performed to evaluate the effect of fondaco, a traditional ripening cellar without any artificial temperature and relative humidity control, on the chemical, microbiological, and sensory characteristics of Protected Geographical Indication Canestrato di Moliterno cheese. Ripening in such a nonconventional environment was associated with lower counts of lactococci, lactobacilli, and total viable bacteria, and higher presence of enterococci, in comparison with ripening in a controlled maturation room. Moreover, fondaco cheese underwent accelerated maturation, as demonstrated by faster casein degradation, greater accumulation of free AA, and higher formation of volatile organic compounds. Secondary proteolysis, as assessed by liquid chromatography-mass spectrometry of free AA and low molecular weight peptides, did not show any qualitative difference among cheeses, but fondaco samples evidenced an advanced level of peptidolysis. On the other hand, significant qualitative differences were observed in the free fatty acid profiles and in the sensory characteristics. Principal component analysis showed a clear separation of the fondaco and control cheeses, indicating that ripening in the natural room conferred unique sensory features to the product
The Impact of Early Basal Leaf Removal at Different Sides of the Canopy on Aglianico Grape Quality
It is known that early removal of basal leaves improves the exposure of cluster to direct
sunlight and UV radiation, which positively influence the phenolic compounds and anthocyanin
concentration of berries. This study was carried out to evaluate the eect of leaf removal applied before
flowering to the basal zone of the canopy at dierent sides (fruit-zone north canopy side, south canopy
side and north–south canopy side, respectively) of Aglianico vines trained to vertical shoot position
system and row oriented to east–west (EW). The study was conducted in the controlled and guaranteed
designation of origin (CGDO) Castel del Monte area (Apulia region, Italy). The treatment did not
aect yield per vine, and nor sugar, pH, and total acidity of grapes. When it was applied to the
basal south canopy side, the concentration of proanthocyanidins and total polyphenols of grapes
increased, as well as antioxidant activity. In particular, anthocyanins content, determined by HPLC,
increased by 20% with respect to control when treatment was applied to south and north–south
canopy sides. Interaction between season period and treatment was found for all anthocyanins
except for petunidin-3-coumaroyl-glucoside. Basal leaf removal applied to the north canopy side
caused an increase in malvidin-3-O-glucoside content in grapes in 2016 and 2018, but not in 2017.
Our results indicate that basal leaf removal (six basal leaves removed from the base of the shoots)
before flowering (BBCH 57) can be used as an eective strategy to improve grape total polyphenols,
anthocyanins concentration and antioxidant activity in vineyards cultivated under warm climate
conditions. The treatment could represent a sustainable alternative to manual cluster thinning since it
does not reduce yield per vine and can be performed mechanically
Quality Characteristics and Consumer Acceptance of High-Moisture Mozzarella Obtained from Heat-Treated Goat Milk
-moisture mozzarella is a pasta filata cheese manufactured from cow or buffalo milk that has spread all over the world. Its manufacturing from the milk of small ruminants (goat and sheep) has been recently proposed to innovate this ailing sector. Previously, a protocol was reported for making goat mozzarella from unpasteurized milk but, according to legislation, the microbiological safety of raw milk fresh cheeses is not guaranteed. In the present research, two new protocols were tested for producing mozzarella from pasteurized milk prepared by two different low-temperature long-time treatments (67 °C or 63 °C × 30 min). The obtained cheeses were subjected to physical–chemical and microbiological analyses and to consumer testing. The results showed that the heat treatments caused longer coagulation times than those reported in the literature, despite pre-acidification (at pH 5.93 or 6.35) having been performed to counterbalance the expected worsening of the coagulation aptitude. The obtained products showed differences in the chemical composition, texture, proteolysis, and lipolysis. Both pasteurization and pre-acidification played a role in determining these variations. Consumer testing indicated that mozzarella obtained from milk heated at the lower temperature and coagulated at a higher pH reached a good level of appreciation (62
Volatiles and acceptability of liqueurs from kumquat and grapefruit
The aim of this work was to produce liqueurs from "minor" citrus fruits, such as kumquat and grapefruit, characterize their volatile fraction and evaluate their acceptability by a consumer test. A limoncello sample (LP) was produced under the same conditions and used for comparison. All the new liqueurs were found to be richer in limonene and poorer in oxygenated compounds than the LP. The volatile fraction was mostly represented (85%) by limonene in grapefruit liqueur. Liqueur from kumquat peel (KP) was the richest in volatile compounds, whereas the one from kumquat whole fruit (KWF) was the poorest. This latter also had the particular feature to be the richest in sesquiterpene alcohols. Octanal and decanal, and two acetals deriving from these aldehydes (1,1-diethoxyoctane and 1,1-diethoxydecane) were most prevalent in KP and LP. The consumer test showed that all liqueurs were judged to be acceptable. Nevertheless, limoncello remained the most preferred, while the KWF liqueur obtained the best flavour score in the group of minor citrus fruits
Effects of slaughter weight and sex on carcass traits and meat quality of Casertana pigs reared outdoors
The effects of different slaughter weights (W) and sex (S) on carcass traits and longissimus dorsi meat quality (pH, WHC, colour, cholesterol and collagen) of Casertana pigs were studied. Thirty-six pure breed Casertana pigs, 24 barrows (B) and 12 gilts (G), were evaluated in a 2x2 factorial design involving different slaughter live weights (L, 125.6 kg; H, 152.5 kg) and S (B and G). H pigs had higher carcass weight (P<0.01), dressing percentage (P<0.05), ham yield (+ 7.9 %; P<0.01), lean meat cuts (P<0.01) and backfat thickness (+13.3%; P<0.05), and lower (P<0.01) loin yield and fatty cuts. W did not affect pH and WHC. L pigs produced lighter (P<0.01) and more yellow meat (P<0.01), while H pigs showed lower (P<0.01) hue value. Cholesterol content resulted higher (P<0.05) in H pig meat. Collagen properties were affected by W. Compared to G, B had higher dressing percentage (P<0.05) and backfat thickness (P<0.01), smaller loin area (P<0.01), slightly lower (P<0.08) loin yield and less (P<0.01) lean cuts. S did not affect any meat quality traits
Effect of intramuscular injections of DL-α-tocopheryl acetate on growth performance and extracellular matrix of growing lambs.
The effect of intramuscular injections of vitamin E on growth, carcass traits, intramuscular collagen (IMC) characteristics and decorin of growing lambs was studied. A total of 24 15-day-old Ile de France suckling male lambs were divided into two groups and weekly intramuscular injections of DL-α-tocopheryl acetate (control group, 0 IU; Vitamin E treatment, 150 IU) were given until the lambs were 64 days old. Lambs were individually weighted at 15, 29, 43, 57 days of age and at slaughter (71 days old). Dry matter intake and average daily weight gain were recorded. Hot and cold carcass weights were recorded and dressing percentages were calculated after dressing and chilling (2°C to 4°C for 24 h). Carcass shrink losses were calculated as well. Longissimus muscle (LM) pH and area were measured. The pelvic limb was removed and its percentage was calculated based on cold carcass weight. IMC and decorin analyses were assessed on LM and semimembranosus muscle (SM). DL-α-tocopheryl acetate treatment reduced (P<0.05) collagen maturity and increased (P<0.05) decorin in both LM and SM muscles of growing lambs, while it did not affect IMC content. In addition, vitamin E did not influence growth, carcass weight, dressing percentage, carcass shrink losses and area of LM but decreased (P<0.05) the pelvic limb percentage. The LM pH values were higher (P<0.05) in vitamin group than in control group. Furthermore, different IMC characteristics between the muscles (P<0.01) were apparent. Multiple intramuscular injections of DL-α-tocopheryl acetate influence extracellular matrix in lambs, which could affect meat tenderness
Exploitation of grape marc as functional substrate for lactic acid bacteria and bifidobacteria growth and enhanced antioxidant activity
This study aimed at using grape marc for the growth of lactic acid bacteria and bifidobacteria with the perspective of producing a functional ingredient having antioxidant activity. Lactobacillus plantarum 12A and PU1, Lactobacillus paracasei 14A, and Bifidobacterium breve 15A showed the ability to grow on grape marc (GM) based media. The highest bacterial cell density (>9.0 CFU/g) was found in GM added of 1% of glucose (GMG). Compared to un-inoculated and incubated control fermented GMG showed a decrease of carbohydrates and citric acid together with an increase of lactic acid. The content of several free amino acids and phenol compounds differed between samples. Based on the survival under simulated gastro-intestinal conditions, GMG was a suitable carrier of lactic acid bacteria and bifidobacteria strains. Compared to the control, cell-free supernatant (CFS) of fermented GMG exhibited a marked antioxidant activity in vitro. The increased antioxidant activity was confirmed using Caco-2 cell line after inducing oxidative stress, and determining cell viability and radical scavenging activity through MTT and DCFH-DA assays, respectively. Supporting these founding, the SOD-2 gene expression of Caco-2 cells also showed a lowest pro-oxidant effect induced by the four CFS of GMG fermented by lactic acid bacteria and bifidobacteria
Effects of Grape Pomace Polyphenols and In Vitro Gastrointestinal Digestion on Antimicrobial Activity: Recovery of Bioactive Compounds
Grape pomace (GP), a major byproduct obtained from the winemaking process, is characterized
by a high amount of phenolic compounds and secondary plant metabolites, with potential
beneficial effects on human health. Therefore, GP is a source of bioactive compounds with antioxidant,
antimicrobial, and anti-inflammatory activity. As people are paying more attention to sustainability,
in this work, we evaluate two different extractions (aqueous and hydroalcoholic) of GP bioactive compounds.
In vitro simulated gastrointestinal digestion of the GP extracts was performed to improve
the bioavailability and bioaccessibility of polyphenols. The antioxidant activity (ABTS and DPPH
assays) and the phenolic characterization of the extracts by UHPLC-DAD were evaluated. The antimicrobial
effects of GP antioxidants in combination with a probiotic (Lactiplantibacillus plantarum) on the
growth of pathogenic microorganisms (Escherichia coli, Bacillus megaterium, and Listeria monocytogenes)
were evaluated. As a result, an increase of antioxidant activity of aqueous GP extracts during the
gastrointestinal digestion, and a contextual decrease of hydroalcoholic extracts, were detected. The
main compounds assessed by UHPLC-DAD were anthocyanins, phenolic acids, flavonoids, and
stilbenes. Despite lower antioxidant activity, due to the presence of antimicrobial active compounds,
the aqueous extracts inhibited the growth of pathogens
Volatilome and Bioaccessible Phenolics Profiles in Lab-Scale Fermented Bee Pollen
Bee-collected pollen (BCP) is currently receiving increasing attention as a dietary supplement
for humans. In order to increase the accessibility of nutrients for intestinal absorption, several
biotechnological solutions have been proposed for BCP processing, with fermentation as one of the
most attractive. The present study used an integrated metabolomic approach to investigate how the
use of starter cultures may affect the volatilome and the profile of bioaccessible phenolics of fermented
BCP. BCP fermented with selected microbial starters (Started-BCP) was compared to spontaneously
fermented BCP (Unstarted-BCP) and to unprocessed raw BCP (Raw-BCP). Fermentation significantly
increased the amount of volatile compounds (VOC) in both Unstarted- and Started-BCP, as well as
modifying the relative proportions among the chemical groups. Volatile free fatty acids were the
predominant VOC in Unstarted-BCP. Started-BCP was differentiated by the highest levels of esters
and alcohols, although volatile free fatty acids were always prevailing. The profile of the VOC was
dependent on the type of fermentation, which was attributable to the selected Apilactobacillus kunkeei
and Hanseniaspora uvarum strains used as starters, or to the variety of yeasts and bacteria naturally
associated to the BCP. Started-BCP and, to a lesser extent, Unstarted-BCP resulted in increased
bioaccessible phenolics, which included microbial derivatives of phenolic acids metabolism
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