Italian Journal of Food Science

"Lisbon" lemons were divided into groups that were coated, packaged in polyethylene bags with or without a pouch containing KOH, or left unpackaged and uncoated; fruits were then stored at 8°C up to 15 weeks. Packaging significantly reduced weight loss and fruit mantained a fresh appearance. Fruits in bags without KOH showed the highest incidence of decay. In fact, KOH moisture-absorbing capability significantly decreased rots during 5 weeks of storage plus one week of shelf-life, if compared to packaged fruits without KOH. No signs of CI were detected in any treatment. Packaged fruits without KOH revealed the highest concentration of ethanol and acetaldehyde in the juice.

The need for a greater diversification of baked products has given rise to the on-going search for yeast and lactic acid bacteria (LAB) strains with optimal baking potential. Thirty-six yeasts and 118 LAB, isolated from nine type I sourdoughs that were sampled in bakeries located in the Marche region (central Italy), were molecularly and phenotypically characterized. The polyphasic approach used revealed the biodiversity of the microbial communities investigated and two yeasts and ten LAB cultures with the potential to be used in sourdough bread-making processes were identified.

Goat milk is a complete food but its low level of folic acid diminisches its nutritional efficacy. In this study, Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lb. delbrueckii subsp. lactis and Lb. helveticus strains were selected for folate production in goat milk to improve its quality. A suitable HPLC method was developed to directly determine both total folate and its biologically active derivatives such as 5-methyl-tetrahydrofolate (5- CH₃-H₄-PteGlu), tetrahydrofolate (H₄-PteGlu) and 5 formyl-tetrahydrofolate (5-CHO-H₄-PteGlu). Results showed that S. thermophilus, Lb. delbrueckii subsp. lactis and Lb. helveticus strains produced higher amounts of total folate than Lb. delbrueckii subsp. bulgaricus , especially 5-CH₃-H₄-PteGlu and H₄-PteGlu. Moreover the use of selected S. thermophilus strains in association with Lb. delbrueckii subsp. bulgaricus resulted in yoghurt with a significant quantity of folate and good organoleptic features.

The meat quality of three poultry genotypes with differing growth rates (fast-growing Ross; medium and slow growing Kabir and Robusta maculata, respectively) was compared. All the birds were reared according to the organic production system which requires a paddock with grass pasture (4 m2/bird) and a slaughter age greater than 81 d. The trial was carried out on 100 female chickens per strain. The meat quality was affected by the 20 different degree of maturity of the strains at slaughter age, which was 70% for Ross, 52 % for Kabir and 78% for Robusta maculata. Ross and Kabir were slaughtered at 81 d, whereas Robusta maculata, required 120 d to reach a commercial weight (>2 kg). The meat of all the three genotypes showed good qualitative traits. The main differences of the three genotypes regarded moisture, lipid, pHu, colour, iron, oxidative stability and overall acceptance. Compared with Kabir and Robusta maculata Ross meat had more fat, lower pHu and iron, and was 25 paler. The oxidative stability during display (24-96 h at 4° C) and acceptance were the worst. Kabir chickens, being the least mature strain, had the highest moisture content with a high cooking loss. The slower-growing genotypes showed a good adaptation to the extensive rearing conditions, while the fast-growing genotype showed unbalanced muscle response to the greater activity and the oxidative stability of the meat was reduced.

Supercritical fluid extraction (SFE) has been combined with supercritical fluid chromatography (SFC) in a preparative mode to develop a system for fractionating and enriching high value phospholipids (PLs) contained in soyflakes. Soyflakes were initially extracted with neat carbon dioxide (CO2) at 680 bar and 80 degrees C to remove the available oil. The defatted flakes were then extracted with 15 mol% ethanol-modified CO2 at 655 bar and 80 degrees C to obtain the phospholipids. This phospholipid-enriched extract was then delivered to the head of a chromatographic column containing neutral alumina. The modifier was then changed to ethanol:water (9:1) and SFC was performed at 350 bar and 50 degrees C, collecting fractions at equal volume intervals of CO2. The SFC modifier was added in an increasing step-wise gradient to affect elution of the PLs. The resultant fractions (analyzed by highperformance liquid chromatography with evaporative light-scattering detection) showed PL enrichment factors relative to the de-fatted soyflakes from a 2.3 to 19.9 fold increase, depending on the individual PL.

We report the results of the effect of some technological corrections, experimented during a three year study, designed to avoid the main processing problems of naturally processed olives. The following processing parameters were kept constant throughout time: salt (2 and 4%), pH (acidification with lactic acid to pH=4), fermenting temperature (25°C) and brine level. Results indicate that pH did not exceed the threshold of 4.5, while there was a weak free, combined and volatile acidity. Sugar and polyphenol diffusion into the brines was higher in the 2% brined olives than in the 4% ones. Gas pockets were not recorded, while a low incidence of irreversible shrivelling was noted only in the 4% brined olives. Panelists rated the olives as excellent for firmness and for residual bitter taste, and expressed a slight preference for 4% olives, because they were saltier.

The response of three Sardinian olive cultivars to processing as table olives with the Greek-style was evaluated. “Bosana”, “Manna” and “Sivigliana sarda” olives were characterised from the marketing, technological and chemical-physical point of view and brined with 8% NaCl. Fermentation was carried out according to the anaerobic method for 150 days. At fixed intervals main brine and flesh parameters were monitored. Evolution of brine chemical parameters showed yeast fermentation. Oleuropein decreased greatly in the flesh after 20 days and totally disappeared in “Bosana” after 90 days. Sensory determinations resulted in good taste and texture for the three cultivars, with “Bosana” being preferred. Gassy alterations were negligible, while shrivelling was not detected.

RIASSUNTO

"Salustiana" oranges were dipped in a 500 mg/L imazalil emulsion and wrapped in polystyrene trays using three different plastic films: Omni, MR and MY, with high, medium and low permeability to gases and water vapour, respectively. Fruits were then stored at ambient temperature (18°-20°C) and relative humidity (60-65%) for 6 weeks. MY film created in-package anaerobic conditions (about 10% CO₂ and 8% 0₂, increased the rate of deterioration of internal quality parameters and promoted pathogen development, even in fruits treated with imazalil (28% decayed fruits after 6 weeks). Omni film did not alter the nutritional composition, but had little influence in reducing the transpiration rate as fruits at the end of storage lost about 14% weight, compared to 18% for non-wrapped fruits and 2% for those wrapped with the other two films. Very positive results were obtained with the imazalil-MR film combination, which let the fruits maintain their initial chemical and aesthetical characteristics during the entire storage time and limited loss due to decay to about 1%.

As a contribution to the study and preservation of indigenous wine yeast populations, we initiated a programme of isolation and characterization of yeast strains from grapes of the Italian region of Marche. During the 1996 vintage, grape samples were collected from three groups of vineyards differing in the pesticide treatments given. Of the 279 yeasts isolated, thirty-nine were assigned to the species Saccharomyces cerevisiae . The majority of the isolates and all thirty-nine S. cerevisiae came from vineyards which had not been treated with systemic pesticides, indicating that these pesticides may exert a negative effect on the biodiversity of the grape microflora, and in particular on the occurrence of S. cerevisiae on grapes. The thirty-nine S. cerevisiae isolated were subjected to microfermentation mals, in which ten of them showed promising fermentative capabilities.

The synthesis of structured 1,2-diacyl-sn-glycero-3-phosphocholines (sn-1,2-PC) from glycerol-sn-3-phosphocholine (GPC) was studied by means of enzymatic acylation reactions of the two free sn- positions of the glycerol backbone. Already after 22 h high conversions (absolute yields = 100%) of GPC to sn-2-lysophosphatidylcholines (sn-2-LPC) were achieved using Novozym 435, a lipase from Candida antarctica, selective for the sn-1-position of GPC. In the second step the acylation of the sn-2-position of the sn-2-LPC was catalysed by phosphollpase A2 from hog pancreas and better acylation yields (40% absolute yield, corresponding to a relative yield of 70%, when the reactions were carried out at controlled water activity) were obtained if compared to analogous reactions reported in the literature. A chemical procedure to obtain structured sn-1, 2-PC from sn-2-LPC was also used and better results (65% absolute yield, corresponding to a relative yield of 95%) were obtained in comparison with the enzymatic method.

11 trace elements (Cr, Mn, Co, Ni, Cu, As, Se, Cd, Pb, Sn, Hg) of 21 different kinds of rice samples from main production regions in China were analyzed by ICP-MS (inductively coupled plasma mass spectrometry). The recoveries were in the range of 80.0-113.7%. The detection limits ranged from 0.010 to 1.904 ng g-1. The results revealed that the concentrations of Hg of 4 rice samples, Pb of 3, Cd of 2 and Cr of 1, exceeded the Chinese permitted levels in foods. And the estimated daily intake was 28.1-46.8 μg for As and 9.4-15.6 μg for Se. This study demonstrates that the potential risk to people's health which is attributed to the daily consumption of these rice samples is probably being existing.

On a set of 84 Large White gilts, reared from 35 to 160 kg live weight, seven dietary treatments were compared: Control diet, supplemented with 30 mg/kg Cu, but with no added E and diets containing 6% high-oleic acid sunflower oil (oil diets), supplemented with 30 or 170 mg/kg Cu both crossed with either 0 or 100 or 200 mg/kg added vitamin E. Growth parameters were not affected by the diet. Dietary oil addition increased the proportion of oleic acid in backfat and lipids from loin muscle, affected the calculated iodine number of the backfat (>70 in oil fed groups), but not firmness; the oleic acid in backfat slightly increased with dietary copper addition. In oil diets, the value of thiobarbituric acid-reactive substances of pork 6 d after slaughtering was 42% lower than that in control pigs. Scant effects on pH(45), pH(u), color and drip losses were observed. The oleic acid content can be safely increased in diets of heavy pig for fresh pork. No advantage was obtained with 170 mg/kg copper addition nor with vitamin E addition to a 6% high-oleic acid sunflower oil diet.

In this study, the seasonal fatty acid and amino acid amounts in the muscles of the zander from Beysehir Lake, Turkey, and their important indices for human health were evaluated. It was found that aspartic acid, glutamic acid and lysine levels in zander were dominant among the amino acids. The ratio of essential amino acids (EAA) to non-essential amino acids (NEAA) was between 0.69 and 0.78. In all seasons, the polyunsaturated fatty acid (PUFA, 89.85-109.11 mg/100g) amount in zanders was higher than saturated fatty acids (SFA, 55.08-81.89 mg/100g) and monounsaturated fatty acids (MUFA, 29.16-78.89 mg/100g). It was determined that EPA, DHA and omega-3 rates were high. The fatty acid quality indices (AI, TI, FLQ, w6/w3, h/H) were found at proper levels for human health. Summing up the results, it was found that seasons influenced both the compositions of amino acids and fatty acids of zander.

The effects of oral administration of 3 mg of 17α-methyltestosterone per kg of administered diet were studied in 35-day-old rainbow trout. The protein, fat, ash and moisture of meat, carcass efficiency, fillet efficiency and the hepatosomatic and gonadosomatic indexes were measured as well as the amount of residual methyl testosterone that might have remained in the meat. Compared to controls, there were no changes in crude protein and ash of the fish meat and in the fillet efficiency, carcass efficiency and gonodosomatic index of the trout. Crude fat of the fish meat and the hepatosomatic index decreased while the moisture increased. No residual 17α-methyltestosterone was found in the meat of treated trout.

Ripe apricots (14-15% soluble solids content, SSC) were treated with 1, 4 and 10% O-2 humidified atmospheres for 9 days at 5 degrees or 18 degrees C, and then kept for 5 days in shelf Life (S.L.) (air at 18 degrees C and 85% relative humidity). Control fruits were continuously kept in air at 5 degrees C for 9 days plus 5 days at 18 degrees or at 18 degrees C continuously. Even though at 18 degrees C during treatment and during S.L., ethylene production was reduced in the low oxygen atmosphere (1 and 4%), firmness of apricots quickly declined; at the end of the test the fruits were judged unsaleable due to texture and flavor by a subjective sensory evaluation. Ethanol content rose more in air and 10% O-2-treated apricots than in low oxygen atmospheres. ADH activities were correlated to ethanol content in the fruits. At 5 degrees C, 1% O-2-treated fruits maintained very good firmness during shelf life and were scored saleable by the sensory evaluation. SSC remained higher than in the other samples. No ethanol flavor was detected at the end of the test. In conclusion, 1% O-2 treatment for 9 days at 5 degrees C is satisfactory to maintain sensorial quality and purchase quality of ripe apricots during 5 days of distribution in air at 18 degrees C.

This study was carried out to detect the concentration of fatty acid in female and male specimens of commercially important giant red shrimp (Aristaeomorpha foliacea) obtained from (including 20 male shrimps and also 20 female shrimp) Mediterranean Sea. In fatty acid composition, the saturated fatty acid fraction was dominant, followed by polyunsaturated fatty acid and monounsaturated fatty acid for both sexes. The analyses indicated that PUFAs, and the MUFAs content were higher in female shrimp than in those of males and they were statistically significant differences in fatty acid profile between females and males (p<0.05).

In this study the sensory and chemical parameters of marinated shad (Alosa immaculata, Bennett, 1838) were determined. Fish were marinated with different package methods (in brine, oil and vacuum packed) and stored at 4±1°C. During the storage period, diffusion of proximate composition, acetic acid and sodium chloride into the fish fillets were determined. At the end of 7 months storage period, TVB-N were 8.05, 16.81 and 17.56 (mg/100 g), TMA were 2.28, 2.53 and 2.73 (mg/100 g), TBA were 7.08, 7.13 and 6.05 (mg malonaldehyde/kg) and pH were 4.42, 4.72 and 4.77 for brine, oil and vacuum packed samples, respectively. Throughout the storage period, effect of different package methods on TVB-N, TMA, TBA, pH, aw, acetic acid, sodium chloride and sensory issues were significant (p<0.05).

High-field Nuclear Magnetic Resonance (NMR) and Gas Chromatography (GC) were used to analyse hazelnut and olive oils in order to evaluate the possibility of detecting hazelnut oil present in adulterated olive oil samples. The fatty acid composition of hazelnut oil was carefully determined and compared with the fatty acid composition of extra virgin olive oil. Linolenic acid content and volatile aldehydes present only in non deodorized hazelnut oils were easily detected with NMR. If the content of linolenic acid was lower than 0.5% or if anomalous aldehydes were present, a full gas chromatographic analysis was performed. Different olive-hazelnut oil mixtures were prepared and analysed by gas chromatography. Linear Discriminant Analysis (LDA) was used to analyse the GC results.

This study presents data from a single laboratory for internal validation of an enzyme-linked immunoassorbent assay (ELISA) for determination of levels of the mycotoxin zearalenone in complementary and complete feedstuff for dairy cattle, calves, sheep and goats. The study was carried out at the request of European Commission (EC) Recommendation 576/2006/EC, in agreement with EC Decision 2002/657/EC on the implementation of EC Directive 96/23/EC and concerning the performance of analytical methods and interpretation of results. This screening detection method has useful advantages: it can analyse large numbers of samples in a relatively short time, with a small quantity of sample required; it is sufficiently robust, reliable and rugged to be statistically sound; and it generates few suspected false negatives (<5%).

Derogations for somatic cell and total bacterial count limits had allowed non-compliant milk to be used for cheesemaking in Italy. Commercial and health considerations prompted a decision to implement a program to gradually repeal the derogations. In this study, we report the statistical evaluation of the situation in 2007-2008, the outcomes of the program to close the derogation and observations of its effects during its implementation from 2010-2013 in the Lombardy region. The introduction of a progressive decrease of the limit allowed regulators to minimize the negative impact on production levels by focusing on the management of the most non-compliant farms first.

A monitoring program aimed at detecting marine biotoxins in coastal bivalves (Mytilus galloprovincialis) of central Adriatic Sea was carried out in the years 2006-2009. The presence of Diarrhoetic Shellfish Poisoning and Paralytic Shellfosh Poisoning toxins was assessed by the Mouse bioassay, as established by the Italian Decree of the Ministry of Health of May, 16, 2002, whereas the Amnesic shellfish Poisoning toxins were detected by HPLC. No biotoxins were determined in all the samples. Since the number of the examined samples was directly proportional to the number of shellfish aquaculture plans located in Abruzzo and Molise regions, these results provide an estimate of the possible shellfish contamination in the considered area.

Ergosterol is an important constituent of fungal cell wall and measurement of it is a useful method to detect fungal activity, which correspond to mycotoxine production. Monitoring of ergosterol content in tomato products in Turkey has been carried out since 2006. The results of monitoring over the period 2006-2010 are presented. During this time 344 samples of six different tomato products (home-made tomato paste, commercial tomato paste, diced or crushed tomato, tomato juice, ketchup and tomato puree) were analysed for ergosterol using high-performance liquid chromatography. The detection limit of ergosterol was 0.1 mg/kg. Recovery experiments were carried out with spiked samples in the range 2-10 mg/kg of ergosterol. Average ergosterol contents were highest in home-made tomato paste (1,074 mg/kg), and lowest in tomato juice (4.5 mg/kg). Ergosterol exceeded the Turkish legal limit of 15 mg/kg in 65 of 88 commercial tomato paste samples; however all home-made tomato paste were >15 mg/kg. This paper reports data of the first survey for the presence of ergosterol in tomato products in Turkey.

The characteristics of vinegar refined in wood receptacles are due to: the period of refining, the volume of the receptacles, the type of wood, the geographic origin of the wood used, the natural or thermic treatments carried out on the wood and the number of cycles for which the receptacle has been used. The EC Regulation regarding the Protected Geographic Indication (PGI) for Balsamic Vinegar from Modena requires an aging period of not less than 60 days in wood barrels. The time of refining, taken as a parameter in isolation from the others, has no relevance whatsoever since all parameters are so closely linked together.

The Istituto Zooprofilattico of Puglia and Basilicata is an accredited analytical laboratory for major mycotoxins (Article 12, EC Regulation 882/2004). During 2010, analytical controls for mycotoxins were started on durum and common wheat imported through the Italian Sea, Air and Frontier Health Offices of Bari and Manfredonia. In the mycotoxins analysis, >80% of the tested samples were contaminated by detectable levels of the mycotoxins, with 5% with an aflatoxin B1 content over the EC Regulations limit, and 1.7% with a deoxynilvalenol content over the EC Regulations limit. These samples were also analysed for quality traits, which showed: 25% of all of the samples had test weights <80 kg; 4.2% had protein content <13%; 40% had gluten index <66; 30% had yellow index b*<24; about 50% had flour strength W between 100 and 200; and almost 40% had a tenacity to extensibility (P/L) ratio <1.5.

In this work we compare the chemical composition of olive fruits (cv Moraiolo) and the sensory and chemical quality of olive oils extracted in two crop seasons: the 2013 crop season, characterized by a very minor attack by the Bactrocera oleae, and the 2014 crop season, characterized by one of the strongest attacks of Bactrocera oleae in the last decades. Results show that during the 2014 crop season the pulp/stone ratio, moisture, phenolic content, oil content, and sugar content were lower than in the 2013 crop season. Moreover, the olive oils from the 2014 crop season were characterized both by higher free acidity values, peroxide value and K232, and by lower values of antioxidants (phenolic compounds and tocopherols). The olive oils from the 2013 crop season did not present any defects, while among those from the 2014 crop season, 41% were defective and did not fall into the extra virgin olive oil category.

The year 2015 will certainly be remembered as the Year of the Universal Exposition (EXPO) hosted in Milan, Italy, focusing on a hot theme in the current scenario: “Feeding the Planet, Energyfor Life”.This event has drawn a wide international attention towards Italy as a country with peculiar and valuable food traditions, thus strengthening its reputation as “gastronomic capital of theworld” rich in protected designation of origin products (PDOs) and characterised by a longstanding food culture.

Carbon dioxide inactivation kinetics of Saccharomyces cerevisiae in potato dextrose broth at 100, 75, 50 and 25 atm was evaluated at 50°. 40°, and 30°C. Inactivation rates increased with increasing pressure, temperature and time. The come-up time to reach a pressure exerts an important effect on the survival of S. cerevisiae. Yeast inactivation followed first order reaction kinetics, with inactivation rates and decimal reduction times that varied from 0.0795 to 0.5722 min-1, and from 4.0248 to 28.9686 min, respectively. The activation volume change of S. cerevisiae pressure inactivation was -526.6, -605.3 and -232.3 cm3/mol at 50°, 40° and 30°C, respectively. The pressure dependence of the yeast inactivation rates can be described by the apparent activation volume (ΔV*) and pressure zp value.

The objective of this study was to investigate Escherichia coli adhesion on new and used polyethylene cutting board surface and evaluate it’s removal using different sanitizer (peracetic acid,chlorhexidine, sodium hypochlorite and organic acids). Results indicated that the number of adherent cells increased with time in both surfaces evaluated. Evaluating the sanitizer action, 0.5%peracetic acid was more effective in removal E. coli than chlorhexidine and organic acids at same concentration in both surfaces. Peracetic acid and sodium hypochlorite also showed effectiveness at concentrations of 0.2% and 0.5% on new surfaces, respectively. 0.8% of chlorhexidine and 2.0% of organic acids showed similar effectiveness in the removal E. coli on new and used surfaces, respectively.These results suggest that peracetic acid is considerable promise sanitizer for application in surfaces of the food processing industry.

This paper reports the results of a study on the ambiguous behaviour of substances with λmax at 280 nm in the determination of total flavonoids in whole grape skin extracts made from a hydroalcoholic SO 2-rich solvent, apparently not eluted with methanol after absorption on a C18 cartridge employed for sample pre-concentration and SO 2 removal. After rejecting the hypothesis that they were irreversibly absorbed on the C18 cartridge, it seemed that they reacted with other phenolics during passage through the C18 cartridge and were totally eluted with methanol in this new combined form. This new hypothesis seems very probable and is in accord with the more recent acquisition about the synthesis of anthocyanins and flavanols.

The effect of hypochlorite on Listeria monocytogenes at varying concentrations, pH, temperature, and type of solution (with or without peptone in phosphate buffer) was studied. L. monocytogenes was reduced by about 3.55, 4.17, 4.56 and 5.59 log units, respectively, after 30 sec of exposure to 5, 10, 50 and 100 mg L-1 hypochlorite in phosphate buffer (pH 6.5) at 30°C. There was an increase in the rate of disinfection (p<0.05) with an increase in temperature from 20° to 40°C. Hypochlorite had a greater antimicrobial effect on L. Monocytogenes at ph 4.5 than at 5.5, 6.5 and 8.5. Addition of 0.1% peptone provided a marked neutralization of the chlorine in the phosphate buffer. Survival curves showed two distinct phases in the destruction of L. Monocytogenes. At all hypochlorite concentrations, the first phase (about 30 sec) was characterized by a higher rate of inactivation, shown by a steeper inactivation slope, which was followed a more gradual slope.

Minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) for oregano EO, cinnamon EO and LAE were determined using a direct-contact antifungical assay by macrodilution method. Cinnamon gave the strongest inhibition followed by oregano and LAE with similar results. LAE showed no antifungal activity in vapor phase, so growth and kill-kinetics were studied by direct contact. Colony diameter of Aspergillus flavus was measured by agar dilution method at different concentrations of cinnamon and oregano EOs, resulting cinnamon EO much more active than oregano EO. In the vapor phase test, the influence of the time of exposure to the cinnamon EO and oregano EO was evaluated, showing relevant differences in their behavior. Kill kinetics showed a different behavior among the three agents.

A pilot feeding trial was performed for four weeks to study the influence of Bifidobacterium lactis 420 on healthy adult volunteers. B. lactis levels increased by more than 1,000-fold. Total bifidobacteria increased only in subjects who had low initial levels. B. lactis 420 appeared to have some influence on the metabolism of the intestinal microbiota and immune markers were only marginally influenced. Interestingly, trends for inverse correlations between faecal TNF-α and IgA concentrations and B. lactis were noted. Further investigation with more subjects is needed to confirm these influences on the microbial metabolic activity.

A method was set up to study the antigenotoxic property of the probiotic Lactobacillus rhamno-sus IMC 501 ® against 4-nitroquinoline-1-oxide (4-NQO). The method is based on liquid-liquid ex-traction followed by gas chromatography-mass spectrometry (GC-MS) analysis. The GC-MS anal-ysis was used to determine the quantitative change of 4-NQO before and after co-incubation with Lactobacillus rhamnosus IMC 501 ® . The results from GC-MS analysis showed that 4-NQO gen-otoxicity was inhibited and then converted to less toxic compounds. These preliminary results from GC-MS analysis indicate that the method described is able to detect physicochemical modi-fications of the genotoxic agent, which occur after co-incubation with bacteria cells. The method, therefore, is a novel alternative to biological assays for detecting the antigenotoxicity of lactobacilli.

A non-caseolytic oligopeptidase from the intracellular fraction of Propionibacterium freudenreichii ATCC was purified to homogeneity by chromatography on Fast Q Sepharose, hydroxyapatite and Mono Q. The enzyme was a monomer of molecular mass approximately 67 kDa determined by SDS-PAGE. At similar activity on bradykinin, the enzyme was less active on alpha(s1)-casein (CN) fragments 1-23 and 165-199 and on oxidized insulin chain B than the 70 kDa oligopeptidase from Lactococcus. The specificity of the enzyme on alpha(s1)-CN fl-23 was somewhat

The paper reports the results of a study aimed at investigating the evolution of the internal atmosphere and the influence of a browning inhibitor treatment on the chemical, physical and sensory parameters of fresh-cut pears (Abate Fetel and Kaiser varieties) stored at 3+/-1 degrees C for 15 days. The fresh-cut pears maintained respiration activity over the storage time; the rate of respiration was influenced slightly by the browning inhibitor dipping. The browning inhibitor treatment delayed the browning and also influenced the quality parameters. The expected shelf-life of fresh-cut pears should be in the range 8-12 days at 3 degrees+/-1 degrees C; but the highest level of quality was maintained for up to 4-8 days of storage.

The total aerobic plate count (APC) and Enterobacteriaceae were evaluated on the surface of ostrich carcasses dressed in three different medium/small-sized abattoirs, where other domestic and/or farmed wild mammals are also slaughtered. Very similar slaughtering procedures are carried out in these plants, but differences exist in skinning methods and final carcass washing. Samples were taken immediately after skinning and at the end of carcass dressing. The mean values of the microbial load were relatively low in all carcasses at each of the two processing steps. The skinning procedure assisted by mechanical air inflation did not negatively affect the surface microbial load. In two plants where final external carcass washing is not a practice, there was a slightly higher APC value at the end of carcass dressing with respect to the value obtained immediately after skinning, thus showing a positive effect of the final carcass washing procedure. In order to evaluate the hygienic standard of the slaughter-line, the microbiological parameters specified by Commission Decision 2001/471/EC for bovine, ovine, and swine carcasses also seem to be applicable for ostrich, but more extensive research is needed.

The enzymic properties of liquid artisanal rennet made using whole abomasa or abomasal tissues or abomasal contents from lambs fed mainly with milk (A) or mainly with grass (B) were studied. The results showed that the yield in milk clotting activity (MCA) was affected by both the diet and the abomasum part. Rennet made from whole abomasurns of A lambs showed the maximum yield in MCA. Chymosin activity was only affected by the diet. Regardless of the part of the abomasum, rennets from A lambs showed over 80% chymosin activity which was significantly higher (p<0.05) than chymosin activity of rennets from B lambs (47.3%-66%). Eserolytic activity was affected by the abomasum part. Rennets made from abomasal tissues showed the highest esterolytic actitvity.

Absorbent pads were made from chlorite-treated (bleached) Sphagnum papillosium and placed on the top and bottom of Atlantic salmon (Salmo salar) individual fillet slices. Each fillet slice was packed in a high-density polyethylene tray in a modified atmosphere of 60:40 N-2/CO2 to a gas: fillet slice volume approximate to 5:1 and stored at +4 degrees C. These trays, and controls (fillet slices with a standard paper absorptive pad or no pad) packed in the same way, were independently removed from cold storage and sampled (n=3) at selected time intervals over a 30 day period. Tray gas composition, water content, water holding capacity, pH, colour, texture, smell, viable bacterial count, amount of soluble protein, amount of acid soluble peptides and free amino acid were assessed for each fillet slice. By the end of the experiment and compared to controls, the smell of the fillet slices stored with Sphagnum pads was deemed to be acceptable to a consumer. Between storage days 7-12 and 19-30 days in the stationary bacterial growth phases these same fillet slices had roughly half the viable bacterial counts per gram slice. No significant differences, between all fillet slices at each sampling interval, were found for any of the other parameters which were assessed, except for free amino acid content. These results show that absorbent pads made from Sphagnum moss may, with further development, have a commercial potential in that they can help extend the shelf-life and the quality of packaged fresh foods such as fish.

In this review, the Author wants to share his experience and opinions after 45 years of academic research on beer. The first part of this review is dedicated to the over time situation of the Italian beer firms. The main core of the paper deals with the historical aspects of the Italian academic research on beer and its relationship with beer industries. The importance of the Italian research is also compared with the European situation. The University Teaching on this matter is also discussed. Finally it is suggested how to further upgrade the quality of the existing University research centres and laboratories. Up to 194 references are presented.

Lipid oxidation is one of the most serious problems occurring during storage of fatty foods, causing a shortage of their shelf-life. In order to predict the shelf life, food industry is very interested in easy, quick and reliable solutions able to estimate the oxygen sensitivity of a product. The degree of lipid oxidation can be measured by physical or chemical methods (i.e. peroxide value -PV) as well as stability tests, which measure the stability of a fatty food under conditions that attempt to accelerate the normal oxidation process. In the field of accelerated shelf-life testing, Oxitest permits food stability to be investigated: it is based on the absolute pressure change in a closed and thermostatted chamber, assumed as the oxygen uptake by reactive substances. The aim of the present study was firstly the assessment of the Oxitest ability to discriminate the growing oxidation degree of soybean oil at different temperatures and secondly to verify the existence of correlation between a common method such as PV and a more innovative accelerated technique like Oxitest. Soybean oil samples were stored at growing temperatures: the evolution of the oxidation was monitored during time by analyzing the samples by both Oxitest and PV. The increase of PV and decrease of the Induction Period (IP) values followed a zero order kinetic at all the different temperatures tested. On consequence the reaction rate constant (k) for each temperature, the Arrhenius parameters and the Q10 index were estimated. The degree of correlation between the two techniques was also evaluated pointing to the Oxitest method as a reliable alternative to classic methods.

The purpose of the author's own research was to analyse the changes in the quality of bakery product stored in an environment of accelerated ageing. The study took into account the impact of the storage temperature on the intensity of variation of the quality parameters in the packaged product. The scope of specific changes of quality occurring in the accelerated ageing environment was subsequently compared to the dynamics of those changes as occurring in the course of long term storage.

Chemical reactions occurring between atmospheric oxygen and food sensitive components are some of the most important causes of food product degradation, thus the possibility to foresee their effects in time is always of great interest in shelf life studies. The aim of this study was to evaluate the applicability, in autoxidation reaction studies as well as colour and flavour loss investigations, of an empirical method based on the absolute pressure change in a closed and thermostatted room, monitoring the oxygen up-take by reactive substances. The instrumental prototype Oxitest is presented as an apparatus able to measure, using accelerated conditions, the oxidative stability of fats, oils or foods, in order to determine their quality or to evaluate their state of preservation. The information potentially obtainable from instrument response regard the induction time of autoxidation process, the amount of oxygen potentially consumable by the product, rate and acceleration of the autoxidation process itself. Different food products were considered, each of them chosen in order to underline specific problems pertinent to the use of the instrument in accelerated ageing tests. Following the obtained results the instrumental prototype Oxitest can be defined as a useful previsional instrument, suitable for studies concerning food products degrading reactions involving oxygen consumption.

Changes in differential scanning calorimetry cooling thermal properties of an extra virgin olive oil in the presence and absence of its phenolic fraction were evaluated at different times of accelerated storage treatment (up to 4 weeks at 60°C under air) and related to lipid oxidation molecules (measured with k232; and k270; indices) and total phenol content. Phenols did not appear to directly influence crystallization of extra virgin olive oil as neither cooling profiles nor thermal properties differed significantly between the two oils at the beginning of storage. However, oilsamples deprived of phenols showed more significant changes at the longeststorage time in comparison with untreated oil. Cooling transitions were all deconvoluted into three peaks. Changes in thermal properties were more evident for the two transition peaks at the highest temperature in both oil samples. Thus, a marked influence of lipid oxidation products on the crystallization pattern of these two peaks may be hypothesized.

Virgin olive oil stability is very high in comparison with other vegetable oils. Accelerated shelf-life tests (ASLT) using temperatures around 100 degrees C are generally employed to estimate the induction period of the oxidation reaction in a short period of time, but no satisfactory correlation has been found with the VOO shelf-life at room temperature. The main goal of this research is, therefore, to study the chemical stability and the autoxidation process of VOO in the attempt to estimate the shelf-life of this product. A good correlation between the time required to reach EU Regulation upper limits for PV, K-232 and K-270, and the temperatures of the assay, up to 60 degrees C, by a potential equation in all samples studied was found. Moreover, a similar slope was obtained; this makes feasible to establish an ASLT method at a temperature below 60 degrees C to estimate shelf-life at room temperature.