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Giuseppe Gambacorta
Ruolo
Professore Associato
Organizzazione
Università degli Studi di Bari Aldo Moro
Dipartimento
DIPARTIMENTO DI SCIENZE DEL SUOLO,DELLA PIANTA E DEGLI ALIMENTI
Area Scientifica
AREA 07 - Scienze agrarie e veterinarie
Settore Scientifico Disciplinare
AGR/15 - Scienze e Tecnologie Alimentari
Settore ERC 1° livello
Non Disponibile
Settore ERC 2° livello
Non Disponibile
Settore ERC 3° livello
Non Disponibile
Background and Aims: In some years, the table grape cultivar Crimson Seedless does not reach the commercially acceptable level of red colour in Mediterranean climates, with negative consequences for the grower. Application of abscisic acid (S-ABA) and sucrose could be a tool for overcoming this problem. Methods and Results: A commercial formulation of S-ABA (400 mg/L) and sucrose (10%) was applied to Crimson Seedless at the beginning of veraison and 5 days later in order to verify the effect on harvestable bunches, skin colour, chemical characteristics, anthocyanin content, antioxidant activity and S-ABA concentration either in the skin or the pulp of the berry. The application of S-ABA and sucrose improved the colour of the berries and increased the amount of harvestable bunches at the first pick (80–95%) compared with that of the control treatment (43%). Ripening attributes (total soluble solids, pH, titratable acidity) were not affected by the application of either S-ABA or sucrose. The S-ABA concentration in skin and pulp increased significantly after the treatments and at first harvest. Abscisic acid increased the concentration of anthocyanins and showed a positive effect on the antioxidant activity. Conclusion: Abscisic acid and sucrose improved the colour of the berry skin, with improved results obtained when S-ABA was applied alone and at the beginning of veraison. Sucrose, although to a less extent, was also effective in improving skin colour and increasing the number of harvestable bunches at the first pick. Significance of the Study: This study provides new information about the positive effect of either S-ABA or sucrose on colour, anthocyanin concentration and antioxidant activity of the berry. Moreover, bunches could be harvested in fewer picks with important economic consequences for the grower and with an S-ABA concentration in the berry within the physiological values.
Crimson Seedless’ is a table grape cultivar that often fails to develop adequate red color in Mediterranean climates. Application of abscisic acid (S-ABA) may be an aid for improving color, but its potential effects on overall quality and S-ABA concentration of the berry should be also considered. We tested two concentrations (200 and 400 mg/L) and different times of application (from 1 week after veraison up to 9 days before harvest) of a commercial formulation of S-ABA (ProTone®) to verify the effect on harvestable bunches, color, chemical characteristics, metabolic profile, and S-ABA concentration in the berry. It was found that either the application of S-ABA at 400 mg/L one week after veraison or the application of S-ABA at 400 mg/L one week and four weeks after veraison positively affected the berry skin color, shifting the hue (h°) from 20 to a more red-violet hue (h° = 11–12). In general, the application of S-ABA, with the exception of the late treatments, enhanced coloration of the berries and increased the amount of harvestable bunches at the first pick because it promoted the skin-coloring process. S-ABA did not affect berry firmness but reduced the berry detachment force. Nevertheless, the values remained sufficiently high and the general quality of the bunch was not compromised. Ripening parameters (°Brix, pH, titratable acidity) were not affected by S-ABA applications, and even the primary metabolite profile was not influenced by the treatments as ascertained by multivariate statistical analyses [principal component analyses (PCA) and partial least squares discriminant analysis (PLS-DA)] applied to nuclear magnetic resonance (NMR) data. The S-ABA concentration in the berry, when treatments were performed around veraison, was within the natural range for grape (10–400 ng/g f.w.), whereas when late treatments were applied (few days before harvest), the concentration was higher (more than 1,000 ng/g f.w.). The best results for yield, quality, and S-ABA concentration in the berry were observed for the treatments performed a few days after veraison at the dose of 400 mg/L. This study gives new information about the positive effects of S-ABA on color without any particular change in the metabolic profile of the berry.
Tra le cultivar ad uva da tavola a bacca rossa coltivate in Puglia, la 'Crirnson seedless' è una delle più importanti per il contributo produnivo offerto alla produzione totale regionale. È una cultivar molto interessante per l'epoca medio-tardiva di maturazione (settembre-ottobre), per produttività, per caratteri qualitativi (pezzatura, consistenza e sapore della bacca), ma presenta frequentemente una colorazione dell'epicarpo non adeguata agli standard commerciali. La difformità di colorazione delle bacche, osservata nei climi caldo-aridi, può dipendere sia dalle elevate temperature estive che dalle limitate escursioni termiche giorno/notte che ostacolano l'accumulo di antociani nell'epicarpo. Per migliorare la colorazione delle bacche della cultivar 'Crimson seedless' si è pensato di ricorrere all 'applicazione dell' acido abscissico (SABA), verificando gli effetti dello stesso sulla qualità generale dell'uva e determinandone la concentrazione nelle bacche alla raccolta. Nell'annata 2010-2011 è stata condotta una prova in un vigneto commerciale di 'Crirnson seedless' in agro di Rutigliano (Ba) per valutare gli effetti dell'S-ABA sulla colorazione e su altri aspetti qualitativi dell'uva. Una formulazione commerciale di S-ABA (ProTone®) è stata impiegata a due concentrazioni (200 e 400 mg/L) ed in diverse epoche a partire dall 'invaiatura. I risultati ottenuti hanno indicato che, al momento della raccolta, l'applicazione di S-ABA ha significativamente influenzato i parametri del colore dell'epicarpo. In particolare, i grappoli trattati con S-ABA alla concentrazione maggiore all'invaiatura si sono colorati prima ed in maniera più uniforme rispetto al testimone, con conseguente anticipo della raccolta di circa 15 giorni, aspetto molto importante dal punto di vista commerciale. Alla raccolta, i valori di consistenza della bacca, °Brix , pH e acidità titolabile non hanno mostrato differenze significative fra i trattamenti. In conclusione, l'applicazione di S-ABA ha svolto un positivo effetto sul colore dell'epicarpo delle bacche di 'Crimson seedless', migllorandone la colorazione commerciale che è stata raggiunta in anticipo.
BACKGROUND:Tworedwines (PrimitivoandUva di Troia) treated withoakchips inoculated with Penicilliumpurpurogenumwere analysed in order toassess their contents of furfural, cis-β-methyl-γ -octalactone, syringol, eugenol, vanillinand4-vinylguaiacol. Two different sizes of oak chips (small and big, of length 2 and 8mm respectively) and two different degrees of toasting (low and high) were used in the study. Aroma compounds were analysed by gas chromatography/mass spectrometry to determine differences among samples after 15 days of chip contact time. RESULTS: Big oak chips inoculated with P. purpurogenum increased the level of 4-vinylguaiacol,while small oak chips inoculated with P. purpurogenum, in some conditions, increased the level of eugenol. Chip size and degree of toasting also played an important role in the content of eugenol. CONCLUSION: The use of oak chips inoculated with mouldmight be a promising alternative to barrel aging. Moreover, different fungal inocula could contribute to the enrichment of wine with specific compounds (e.g. 4-vinylguaiacol and eugenol).
Ciauscolo is a short-ripened fermented sausage manufactured in the Marche region (central Italy) that has recently received a protected geographical indication product classification (PGI). The aim of this study was the exploration of the biochemical traits of this traditional Italian salami, with a special focus on protein and lipid composition. Ciauscolo salami was characterized by pH of 5.1 and 0.91 water activity. A prevalence of lactic acid bacteria in the microbiota was found. The free amino acids and biogenic amines average content was 2657 and 255 mg/kg, respectively. With regards to lipids composition unsaturated fatty acids represented 63% and 72% of total and free fatty acids. Despite these results had wide statistical variability, attributable to differences in the processing parameters and raw matter used, some peculiar traits were found: (1) structural muscular proteins underwent to less proteolysis than sarcoplasmic ones; (2) glycogen phosphorylase, enolase, and aldolase were the most proteolyzed among the sacoplasmic proteins; (3) there was inverse correlation between histamine content and yeasts population, and a direct correlation between the gly-pro content and lactic acid bacteria counts; (4) the content of aspartic acid and methyonine seem to be a possible molecular marker able to distinguish between double and single milling.
tThe popularity of pomegranate (Punica granatum L.) is increasing among growers and consumers due toits nutritional value, nutraceutical properties and adaptability to different soils and climate conditions.Pomegranate is characterized by a large variability in terms of domestic, wild and ornamental genotypes,and for seed-hardness, juiciness, rind and aril color, sugar/acid ratio, antioxidant activity, fatty acids, phe-nols and arils anthocyanins content. Evaluation of pomegranate germplasm has usually been performedusing fruit morphological and chemical traits, whereas genetic studies received less attention. The aimof the present work was: (a) to carry on a morphological and biochemical characterization of a set ofpomegranate genotypes collected in Puglia region, Southeastern Italy and (b) to investigate genetic diver-sity by microsatellite markers. A two-year study was carried out for the evaluation of 13 pomegranategenotypes, sweet and sour, of Italian and Israeli origin. Significant differences were observed for many ofthe parameters investigated, in particular fruit and aril size and maturity index of fruits, titratable acidity,total polyphenol content and antioxidant activity of juices and oil content of seeds. Genetic analysis on thepomegranate collection identified 53 SSR loci able to distinguish the different genotypes and to estimategenetic distances. In the dendrogram, pomegranate genotypes clustered according to both geographicalorigin and morphological–chemical traits (skin color, size, taste and polyphenolic content), suggestingthat SSR markers could be effective to detect the genetic diversity of pomegranate, thus facilitating theexploitation of this fruit species germplasm. In general, morphological, chemical and genetic parametersallowed to clearly distinguish the Italian genotypes from the Israeli ones.
Milk from farms located in less-competitive areas of Europe can be appraised by characterizing the specific features deriving from the territory. In the present study milks were compared from Apulian farms, situated in the same area (Murgia highlands) but with different feeding techniques. Through the volatile compounds profile, assessed by the SPME technique and GC-MS analysis, it was possible to discriminate the milk produced by grazing cattle from that produced in intensive dairy farms. In particular, the results confirmed that terpenoids are a powerful chemical index to identify milk which comes from grazing cattle and that these could also indicate the origin from a specific micro-area.
Phenolic compounds have antioxidant properties and activate endogenous detoxification defense systems able to scavenge the reactive species of oxygen. The external layers of wheat caryopsis, largely constituting by-products of the milling industry such as bran and various middlings, contain relevant amounts of phenolic compounds. The aim of the research has been to evaluate the effect of supplementation with wheat bran aqueous extracts, obtained by ultrasoundassisted technologies, on the sensory properties and antioxidant activity of dry pasta. The HPLC-DAD characterization of the extract evidenced the presence of ferulic and p-coumaric acids. The supplemented pasta showed significantly higher antioxidant activity and phenolic content than the control, coupled to good overall sensory judgment. In addition, two different pasta drying diagrams were adopted, and the comparison of the corresponding end-products allowed it to be pointed out that the processing technology has to be carefully set up to prevent possible detrimental effects on the antioxidant activity. The proposed utilization of bran might add value to a milling by-product that, otherwise, is mostly employed in animal feeding.
In this study, a starter culture was tentatively made by testing autochthonous Lactobacillus and Staphylococcus strains, isolated from traditional ‘Salsiccia Sarda’ sausage. Three sausage-making trials were carried out using an association of Staphylococcus xylosus ? Lactobacillus curvatus (A), Staphylococcus xylosus ? Lactobacillus plantarum (B), and Lactobacillus plantarum alone (C). Microbiological profiles, free amino acids, biogenic amines, and free fatty acids were evaluated after 21 days of ripening. Sausages A and B showed the highest number of lactic acid bacteria that produced a rapid acidification of substrates and reduced the number of spoilage microorganisms. Sausages made with L. plantarum alone or together with S. xylosus had the highest content of free amino acids, whereas the one produced with S. xylosus ? L. curvatus showed the lowest content of total biogenic amines and best acceptance score. No significant differences among samples were found as to the free fatty acids concentration.
Quality indices, antioxidant compounds, and antioxidant activities of extra-virgin oils from Coratina olives were evaluated during a 12-mo storage.Whole and stoned olives, picked at 2 different maturation index (MI), were submitted tomalaxation for 45min and extracted by a 3-phase continuous system. A 90-minmalaxation trial was also performed for the stoned olives. The following parameters were monitored: free acidity, peroxide value, K232 and K270 indices, sensory profile, total phenolic content (TPC), phenolic profiles, tocopherol compounds, and antioxidant activity (AA). The highest TPC, AA, and sensory score were found for the oils obtained by olives picked at lowMI and by stoned olives. After 12 mo, all the oils were still included into the “extra-virgin” category, and those deriving from whole olives picked at the lowest MI showed the best sensory characteristics due to high fruity and well-balanced pungent and bitter tastes.
Negroamaro is an autochthonous wine grape variety of Southern Italy, which is becoming very important for the Italian wine market. The wine aroma is primary affected by the chemical composition of grapes, which can be influenced also by agronomic practices such as soil management. In this study, the free and bound aroma characterization was performed by gas chromatography–mass spectrometry analyses, and the influence of two soil managements (cover cropping and soil tillage) was evaluated. A total of 40 volatile compounds were observed in the wine samples. Alcohols (55.7mg/L), fatty acids (7.0mg/L) and esters (6.6mg/L) were found as the main classes in Negroamaro wine. The results showed that the aroma composition of Negroamaro wine was positively affected by soil tillage probably because of the higher water stress (cs) recorded in the vines from this treatment. Indeed, among the free volatile compounds, higher contents of esters, carboxylic acids, alcohols, phenolics and acetamides together with lower contents of sulfurs compounds were found in soil tillage wine. Conversely, no difference was observed in glycoside volatile compounds.
A large increase in the demand for high-quality virgin olive oil continuously stimulating the search for new technologies. In olive oil extraction process, is known that to extract greater oil amount longer kneading time at optimal temperature is needed or, alternatively, higher process temperature. However, both high temperature and longtime of malaxation goes in damage of oil quality, oxidation processes are enhanced and losses in sensory characteristics take place. The malaxer is a heat exchanger characterized by a low overall heat transfer coefficient. At industry scale, extra malaxation time is required to reach the optimal paste temperature, usually around 15- 20 minutes for 30°C. The aim of this work is to show the results obtained from experiments carried out, at laboratory scale, applying high-power ultrasounds during the malaxation step and its effect on oil characteristics. High-power ultrasound application on olive paste has shown a positive effect on length of malaxation step. It provides a quick-heating of olive paste without alteration of olive oil composition. Two main mechanisms are involved in the ultrasonic treatment on olives and on olive paste: a thermal effect and a mechanical effect. The thermal effect was due to the attenuation characteristics of the medium. The mechanical effect is due to cavitation or particulate streaming which cause violent movement of the particles of the medium. Sound waves, which have frequencies higher than 20 kHz, are mechanical vibrations in a solid, liquid and gas. Unlike electromagnetic waves, sound waves must travel in a matter and they involve expansion and compression cycles during travel in the medium. Expansion pulls molecules apart and compression pushes them together. The expansion can create bubbles in a liquid and produce negative pressure. The bubbles form, grow and finally collapse. Close to a solid boundary, cavity collapse is asymmetric and produces high-speed jets of liquid that have strong impact on the solid surface and can disrupt biological cell walls. The mechanical effect of ultrasounds promotes the release of soluble compounds from the plant body by disrupting cell walls and improves mass transfer also in the olive tissues. The ultrasound technology provides a reduction of malaxing time improving extractability of oil and its antioxidant content both of Coratina and Paranzana variety.
The purpose of the present work was to assess the influence of water stress and cover cropping on the phenolic fraction of Aglianico and Nero di Troia grapes and wines, produced in 2007 and 2008 in Apulia region, Italy. Two parcels with soil tillage and cover crop, using Festuca rubra, Festuca ovina and Trifolium subterraneum, were considered. Each of the two parcels was divided into three sub parcels, and each one was subjected to different irrigation volumes corresponding to 36%, 24% and 0% of crop evapotranspiration, respectively. Grapes were submitted to traditional red winemaking using 5 days maceration, without any other oenological treatments. Results showed that the content of some phenols is strongly influenced by the season and water deficit, and partly by soil management. Water stress together with soil tillage led to an increased of phenolic compounds in grapes and, consequently, in wines, suggesting that the use of these agronomic practices could improve the oenological potential of the two cultivars grown in Apulia.
The aim of this study was to assess the influence of different winemaking technologies on the chemical characteristics and, in particular, on the phenolic fraction of Aglianico, Montepulciano, Nero di Troia and Sangiovese wines produced in Apulia, Southern Italy. Four different winemaking technologies were compared: control (traditional, 5 days of maceration at 25°C with three daily punching-down), prolonged maceration (10 days), addition of ellagic tannins, and cryomaceration (24 h at 5°C using dry ice), without any other oenological treatment. Results showed that the different technologies slightly influenced the phenolic fraction of Aglianico, which is known to be naturally rich of phenols. On the contrary, the prolonged maceration led to an increase of total phenols (TP) in Nero di Troia (2592 mg/kg versus 2115 mg/kg of control) and a decrease in Sangiovese (869 mg/kg versus 1013 mg/kg); the addition of tannins led to an increase of TP in Montepulciano (1358 mg/kg versus 1216 mg/kg) and to a decrease in Sangiovese (916 mg/kg versus 1013 mg/kg); cryomaceration led to a decrease of anthocyans in all cultivars (about 15%). Phenols extraction from grapes was found to be mostly dependent on the grape variety rather than on the applied winemaking technology.
The aim of this study was to assess the impact of some viticultural practices (VP) and winemaking technologies (WT) on phenolic composition and sensory characteristics of Negroamaro wines produced in Apulia, Southern Italy. Among VP, two soil management (cover crop and soil tillage) and two training systems (bilateral cordon and unilateral cordon) were compared, whereas among WT, three vinifications were tested: control (traditional, 7 days of maceration at 25 °C with two daily punching-down), cryomaceration (24 h at 0 °C using dry ice) and ultrasound (37 kHz, 150 W, 15 min at 30 °C). Results showed that cover cropping decreased the concentration of flavonoids, whereas bilateral cordon training led to an increase of flavonoids and total polyphenols. Among technologies applied, the cryomaceration led to enrichment in anthocyanins and to impoverishment in total polyphenols, whereas ultrasound treatment improved the extraction of all phenol classes. Cryomacerated wines from the combination soil tillage and unilateral cordon were characterised by the best olfactory and gustatory sensory characteristics. Cryomaceration increased the notes of soft fruits and liquorice, whereas ultrasonic treatment did increase descriptors of violet, soft fruits and black pepper.
The content of lead and cadmium in milk produced near a rural area subjected to illegal dumping and the transfer of the two metals from milk to Mozzarella cheese were investigated. The concentrations found in milk (from 2.00 to 19.17 for Pb and from 0.04 to 1.43 mg L -1 for Cd) did not exceed the maximum limits established by European Community regulations. The cheese-making process was responsible for the transfer of the metals into the cheese but the level of contamination differed, also depending on the dairy, the production technology and the extent of exogenous contamination. On the whole, the contribution that Mozzarella makes to the daily intake of lead and cadmium appears to be toxicologically negligible.
BACKGROUND: Three new artichoke seed-propagated hybrids (Tempo, Opal and Madrigal) were compared with two standard cultivated varietal types [Catanese and Violet du Provence (VP)] in terms of head morphology, processing performance, nutritional or technological qualitative traits, in order to define their best use. RESULTS: Compared to the other genotypes, Opal and Madrigal had more rounded, heavier, larger heads, higher processing yield (>400 g of heart kg−1 raw head) and lower total phenol (TP) content (2.4 g of gallic acid equivalents kg−1 FW). VP gave a higher processing yield than Catanese and showed the highest TP content (6.5 g kg−1 FW). Tempo hearts were more similar to those of VP in biometrical and chemical terms (P, Na, K, Ca); they had the highest dry matter content (163 g kg−1 FW) and the waste left after peeling had the highest TP content. CONCLUSIONS: Hybrid artichokes, especially Opal andMadrigal, appear more suitable for the processing industry and also for fresh-cut production due to their highest processing yield and lowest total phenol content. Because of its high total phenol content, Tempo waste represents a possible source of natural antioxidant in the pharmaceutical field and in the food industry (as a food additive).
The aim of this study was to evaluate over two seasons (2007 and 2008) the effect of cover cropping and irrigation on the phenolic composition of grapes from two red cultivars (Aglianico and Nero di Troia) grown in Southern Italy and of their corresponding wines. Cover cropping led to impoverishment in phenols of grapes and wines of Aglianico and to enrichment of Nero di Troia. For both varieties irrigation deficit led to higher contents of anthocyanins and total polyphenols, indicating that their concentration is closely related to water stress intensity. Some differences were found according to season: Aglianico grapes and wines produced in 2008 were richer in phenols than those produced in 2007, whereas an opposite trend was observed for Nero di Troia. The study demonstrated that the application of modulated water stress to the investigated cultivars allows one to obtain wines very rich in phenolic substances, thus improving the wine quality.
Phenolic composition and antioxidant activity of several monovarietal extra-virgin olive oils used as blenders for the production of “Collina di Brindisi” protected designation of origin (PDO) oil, produced between December 2008 and January 2009 using two-phases or three-phases extraction system, were evaluated and compared with other manufacturer products designated as PDO. Oils were taken from the most representative ones industrial oil mills in the PDO geographical area. The parameters assessed were free acidity, peroxide value, K232 and K270 indices, organoleptic characteristics, total phenolic content (TPC), phenolic profile, and antioxidant activity coefficient (AAC). The phenolic contents and profiles of the monovarietal oils showed remarkable differences with respect to PDO oils. The variables that exerted a major influence on phenols concentration were the maturity degree of olives (December > January), followed by the extraction system (two-phase > three-phase), and place of growing. The Pearson r correlation index showed that AAC was positively correlated with TPC, p-coumarate and 3,4-DHPEA-EA, and negatively correlated with peroxide value.
Artichoke by-products are rich in phenolic compounds although they represent a waste for the food industry. This paper examines the application of ultrasound-assisted extraction (UAE) for obtaining organic solvent-free extracts rich in nutraceuticals from artichoke scraps. Application of ultrasounds for 60 minutes on test samples, using water as a solvent, improved recovery of phenolic substances compared with untreated samples. Among the phenols detected by high performance liquid chromatography, 5-O-caffeoylquinic and 1,5-di-O-caffeoylquinic acids were identified. In vivo treatments of tobacco BY-2 cells with ultrasonic extracts consistently enhanced their antioxidant power, making the cells more resistant to heat stress. UAE applied to artichoke by-products, using water as a solvent, appears to be a powerful eco-friendly technique that can provide extracts rich in nutraceuticals and turn waste products into resources. The extracts could be advantageously utilized in the food industry to produce functional foods.
The aim of thiswork was to characterize the physico-chemical, sensory and volatile profile of functional biscuits enriched with grape marc extract. Control biscuits, without the addition of extract, were produced for comparisons. The enriched biscuits showed higher phenolic content and antioxidant activity than control.Moreover, they had higher sensory scores for color (confirmed by greater values of a* and 100-L*), fruity odor, and sour taste, coupled with lower friability. The volatile analysis pointed out higher amounts of compounds derived from Maillard reaction (with the exception of pyrazines) and from lipid oxidation. The latter, imputable to the presence of grape seeds in rawmaterials, were far fromprovoking off-flavors. The principal components analysis, carried out on the volatile compounds and color data, discriminated biscuit types on the basis of the presence of grape marc extract. PC1 explained 68% of data variability.
Innovation in the small ruminant dairy sector faces structural challenges because dairies are often involved in breeding and produce cheeses that appeal essentially to local markets using traditional technologies and facilities. An investigation was carried out to produce Fior di latte, a traditional, soft pasta filata cheese, from sheep and goat milks at the farm level. Fior di latte is an Italian high-moisture, round mozzarella currently produced from cow and water buffalo milks; it is very popular in Europe. Cheesemaking trials were performed and the most appropriate technology proved to be a combination of direct acidification and lactic fermentation, with some modifications to the milk coagulation phase. The gross composition of the experimental cheeses was similar to that of bovine Fior di latte, and the overall hygienic quality was satisfactory even though the milk had not been pasteurized. The new cheeses were similar in appearance to the bovine type, but some specific features were detected. Besides the typical “goaty” and “sheepy” flavors, some novel and distinctive descriptors of odor, flavor, and texture were noted. Our experiment showed that good quality Fior di latte cheese that complies with microbiological requirements of the European legislation can be obtained from sheep and goat milks by appropriately modifying the cheesemaking technology.
A study was undertaken on Cacioricotta, a traditional Italian goat’s cheese obtained from overheated milk (90 °C) without use of starter. The proWle of proteolysis in the artisanal type, made with vegetable coagulant (latex released from capriWg branches) as milk clotting agent, was compared to that of the “industrial” one, manufactured with calf rennet. Particular aim of the investigation was to study the diVerences and, possibly, establish a useful tool for distinguishing the two types of cheese. The study was based on the quantiWcation of the water soluble, 15% TCA soluble and amino acid nitrogen fractions, RP-HPLC separation of low molecular weight peptides and their identiWcation by mass spectrometry (MALDI-ToF MS). The use of Wg latex was associated to higher amounts of the nitrogen fractions and to RP-HPLC chromatograms very rich in peptides, in contrast to an almost complete lack of peptides in the industrial counterpart. These results conWrm the strong proteolyitic activity exerted by the capriWg clotting enzymes in spite of the intense overheating of the milk, which is considered to cause reduction of the rate of casein degradation in cheese. The MS-based identiWcation of several peptides provided a support at the molecular level for the characterization of Cacioricotta made with this vegetable coagulant and could be useful for “tracing back” purposes. In conclusion, the peptide pattern determined by the use of capriWg for milk coagulation can be considered a particular feature of the artisanal Cacioricotta, giving conWrmation of its vocation to EU protection as typical product.
Italian traditional mozzarella is a high moisture table cheese that is sold packaged in water for preserving freshness. Despite of the high foreign demand, high perishability limits export. For extending shelf life, the dairy industries have long been engaged in controlling the growth of spoilage microflora, which is the main responsible of alteration. The present paper describes the results of a study that aimed to assess if using acidified brine instead of water, the growth of these microorganisms could be delayed. A suitable brine was first developed, based on calcium lactate and lactic acid, that did not impair the sensory characteristics of the cheese. Then, the shelf-life study was carried out, and the results revealed a significant delay of the growth of total mesophilic bacteria, Pseudomonas spp. and Enterobacteriaceae. The sensory characteristics of the cheese remained within the acceptability limits until 21 days and, compared with the sample stored in water, the shelf life was extended of more than 50% Very interestingly, the experimental brine also prevented the occurrence of the blue discoloration defect, known to be caused by Pseudomonas fluorescens. Even though further investigation is needed, the results obtained can open new marketing perspectives for producers of traditional mozzarella.
Uno dei fattori limitanti la conservabilità della mozzarella vaccina sta nel fatto che essa resta immersa in acqua per tutta la vita commerciale. In queste condizioni la qualità decade rapidamente, a causa di fenomeni di tipo microbiologico e biochimico, ma anche di tipo fisico-chimico. Per prolungare la shelf-life senza ricorrere a liquidi “non naturali”, vi è interesse a mettere a punto soluzioni saline da impiegare in sostituzione dell’acqua, che possano preservare la sapidità e proteggere la mineralizzazione degli strati superficiali del prodotto. La presente ricerca ha testato due soluzione saline (soluzione A: CaCl2 0,1 % + NaCl 0,30 %; soluzione B: CaCl2 0,20% + NaCl 0,50 %), a 3 differenti pH (3,5, 4,5, 5,8), su mozzarelle ad acidificazione diretta (acido lattico), di buona qualità microbiologica, a medio contenuto di umidità, conservate per 15 giorni a + 6 °C. I formaggi ed i liquidi di governo sono stati sottoposti periodicamente ad analisi chimiche, microbiologiche e sensoriali. I migliori risultati sono stati riscontrati nel caso della soluzione B a pH 4,5: i campioni non hanno mostrato significativi cambiamenti fino al 12° giorno e, solo al termine del periodo di osservazione, è stato riscontrato un inizio di deterioramento strutturale. In conclusione, l’impiego di CaCl2 0,20% + NaCl 0,50 %, a pH 4,5 può garantire, per la tipologia di prodotto testata, una shelf-life superiore alle due settimane operando in adeguate condizioni igieniche.
Ricotta forte is a traditional whey cheese, obtained through natural fermentation of fresh ricotta, that is getting increasing attention by food traders. In view of possible initiatives for its valorization, the chemical and sensory characteristics were investigated. Samples were obtained from 14 different manufacturer, and were subjected to chemical, biochemical, volatile organic compound, and sensory analyses. All samples presented low pH with high moisture (62-66%) and fat content (57-60% on dry matter). From a biochemical point of view, the electrophoretic patterns evidenced that β-lactoglobulin was the main protein present at all sample ages. Only intermediate levels of proteolysis (20.69% ripening index) took place during aging, whereas the main biochemical event in this dairy product was lipolysis (2.10 mEq/g of acid degree value). Accordingly, free fatty acids dominated the volatile organic compound profile and strongly influenced the sensory characteristics with flavor described as rancid, pungent, acrid, and smelly feet: all associated with short-chain fatty acids such as acetic, propionic, butyric, and caproic. Finally, the sample age did not influence chemical composition, whereas it had significant effect on lipolysis and flavor intensity.
The work described in this Research Communication addressed the hypothesis that it is possible to produce cheese from donkey milk by appropriate adjusting of the cheesemaking parameters. A series of coagulation trials were performed on donkey milk, alone or fortified with goat milk (85/ 15 and 70/30, v/v), using calf rennet under different technological conditions. The parameters that changed were pH and concentration of soluble calcium, amount of rennet added and temperature of coagulation. Donkey milk gave rise to sufficiently firm curd only at ‘extreme’ technological conditions and, as expected, addition of goat milk improved coagulation. A cheesemaking protocol was developed for producing fresh cheese prototypes, which were checked for microbiological safety, chemical composition and sensory characteristics. Pure donkey milk gave 5·9% yield, cheese having 6·12 pH, 32·4%dry matter, 2·1% fat and 18·5% protein. The electrophoretic analysis ascertained that β-casein was the most abundant compound in donkey cheese, but whey proteins were also present in non-negligible amounts. Finally, the sensory evaluation demonstrated that all cheeses were acceptable and provided detailed description of their flavour characteristics.
Artichoke plant is rich in polyphenols and “phytochemicals” molecules that present choleretic, diuretic, hypocholesterolemic, antilipidemic and antihepatotoxic properties. Therefore, artichoke is a suitable vegetable for the extraction of antioxidant compounds useful for the prevention of cancer, cardiovascular disease and other diseases. These compounds are generally phenolic acids, particularly caffeic acid and its derivatives mono and dicaffeoylquinic acids, and simple and glycosylated flavonoids. These active ingredients are contained in the edible part used for food processing, and in leaves, stems and bract residues that represent the by-products of artichoke processing. The purpose of the present work was to extract nutraceutical substances from artichoke byproducts by using an innovative technology based on ultrasound. The use of water as a solvent could allow performing the process in sustainable way, in order to obtain extracts that could be utilized in food industry to produce functional foods. To obtain the extract, a minced aliquot of artichoke by-product was diluted with water (1:10,w/v), put in ultrasonic bath and submitted to ultrasound treatment using the following operative conditions: frequency 40 kHz, power effective 200 W, ultrasound intensity of 0.6 W/cm2, time 60min (three replicates). A not ultrasound-treated sample was used as control. The extracts were submitted to analysis of total polyphenols (Folin-Ciocalteu), antioxidant activity (ABTS, DPPH),and phenolic profile by HPLC-DAD. In comparison to control, the extracts obtained at the end of ultrasound treatment showed higher total phenolic content (about 40%), and higher antioxidant activity (40 and 110% for ABTS and DPPH, respectively). Concerning the phenolic compounds, the ultrasound extracts had the same profile of control, but showed a greater concentration. In conclusion, the ultrasonic extracts from artichoke by-products were found to be richer in total phenolic content and antioxidant activity, and could be used in preparation of functional food.
Malaxation is a basic step in the mechanical olive oil extraction process that may affect yield, quality and health properties of virgin olive oil (VOO). The operative conditions of malaxation, such as temperature and time, are fundamental to favour the oil coalescence process and, consequently, the duration of the VOO extraction process. The aim of this study was to improve the extraction process efficiency by using an ultrasound treatment of olive paste before the malaxation step. The ultrasonic treatment was applied to Coratina and Peranzana, which are two of the most popular Southern Italian olive varieties characterized by extremely different technological performance. Different times of ultrasound treatments were tested (0, 2, 4, 6, 8, 10 min) and free acidity, peroxide value, K232, K270, sensory analysis, tocopherols, total carotenoids, chlorophyll and total polyphenols were determined. Results showed that the ultrasound treatment caused a quick heating of the olive paste as a function of the ultrasound treatment time. Times of treatment of 8 and 10 min allowed the reduction of the malaxation phase from 60 to about 40 min. The ultrasound technique improved antioxidant content in both VVOs, except for polyphenols that decreased. However, the reduction of polyphenol concentration in Coratina VOO improved its taste by reducing the bitter and pungent notes, which are not always accepted by consumers.
BACKGROUND:Oak barrels are commonly used in the aging ofwines and spirits because of their positive effects on the product. In recent years the addition of oak chips hasbeen used to introducedesirablewoodaromas andflavours into wines. In this study, oak chips in saline solution or laboratory medium were inoculated with Penicillium purpurogenum, Aureobasidium pullulans, Phialemonium obovatum,Phanerochaete chrysosporium and a combination of Ph. chrysosporium and A.pullulans.After 12 weeks of incubation, oak chips (2 g L−1) weremacerated in a red wine for 17 days. Gas chromatography/mass spectrometry and highperformance liquid chromatographywere used to evaluate 14 compounds, namely furfural, furfuryl alcohol, guaiacol, syringol, cis-β-methyl-γ -octalactone, 2-phenylethanol, 4-vinylguaiacol, benzyl alcohol, 2,3-butanediol, γ -butyrolactone, benzaldehyde, 4-ethylguaiacol, gallic acid and ellagic acid. RESULTS: Themicrofungal treatments increased the concentration ofsomecomponents. Inparticular, P.purpurogenumresulted in a significant improvement in the levels of guaiacol, furfural, syringol, furfuryl alcohol and 2-phenylethanol. CONCLUSION: Penicillium purpurogenum and Ph. chrysosporium showed a constant trend (enrichment of furfural and benzaldehyde) independent to some extent of themedium used for chip treatment. c 2010 Society of Chemical Industry
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