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This work was aimed to the preliminary development of an enzymatic wheat conditioning process in order to partly hydrolyse the fibre fraction to increase both milling yield and antioxidant capacity of whole flour. Two different commercially available food grade enzyme preparations were selected and used: Viscozyme® L (a complex including several carbohydrase activities) and a 50:50 mixture of Celluclast® BG and Fungamyl® Super AX (a mixture of purified 1, 4-Î2-xylanase and a fungal a-amylase). Lab-scale conditioning trials were carried at 16 % final grain moisture, under stirred conditions for 24 h. The investigated process variables were: working temperature (25 °C and 40 °C) and enzyme addition (3 % w/w based on dry weight of wheat, at 25 °C). All the samples and a control (not conditioned grain), were ground in a domestic mill and the flours were analysed to evaluate the influence of the treatment on: friability of bran fraction (flour weight fraction with particle size < 0.5 mm); free glucose and xylose content; total dietary fibre content; total free phenols (expressed as equivalents of ferulic acid based on Folin's assay) and antioxidant capacity (according to different in vitro test: ABTS, FRAP and ORAC assay). Use of enzymes significantly increased the bran friability since the % of flours with particle size < 0.5 mm was 14 % higher than in the samples conditioned only with water. The free glucose content was 350 % higher in the enzymatically treated flours, while free xylose was detected only in the flour treated with the Celluclast®-Fungamyl® mixture. The total dietary fibre content was decreased by the Viscozyme® treatment. Both the enzymatic treatments improved the antioxidant capacity of flour based on ORAC and FRAP assays, but not the total phenols content and the ABTS-antioxidant capacity. The results showed an effect of the enzymes on the cell wall components, suggesting interesting potential for the development of an enzymatic whe

Aim of this work was to create an innovative walnut product able to increase the shelf life of the walnuts themselves and consequently facilitate their industrial use. Main purpose was to protect the walnuts against rancidity, making the fat fraction less exposed to oxidizing agents and preserving all the well-known positive compounds of the fruit (polyunsaturated fatty acids, vitamins, fiber and antioxidants). To this end an encapsulation process was developed consisting of three different stages: roasting and milling of walnut kernels for paste production, adding of different coating materials for emulsion formation, drying of emulsified samples by lyophilization. Different encapsulation agents (maltodextrin DE12, tragacanth gum, starches, and whey protein concentrates with 80% and 50% proteins on dry basis) were tested, either individually or in combination, in order to assess the effect exerted by different formulations and technological treatments on the product stability. Preliminary tests were carried out to select type, concentration, and combination of coating materials. The fittest samples were therefore examined in terms of residual moisture, pH, total acidity, color, peroxide value, conjugated dienes and trienes. Phenolics and compounds resulting from the oxidation process were detected using an ultra-high performance liquid chromatograph coupled to quadrupole-time-of-flight mass spectrometer (UHPLC/Q-TOF). Analysis were carried out immediately after freeze-drying, and on freeze-dried products after 15 day 60°C storage. Chemicals found in the fresh lyophilized and in the stored samples were identified and compared through the loading plot: flavonoids (flavanones and isoflavones) and phenolic acids, proved to be the most detected differential compounds. The formulation consisting in walnut paste added with 0.2% tragacanth gum, 15% whey protein concentrates with 50% protein/d.m., and 18.3% maltodextrin DE12 allowed to obtain a freeze-dried product with g

Niente dumping per le conserve di pomodoro

Vinegar is an inexpensive commodity, and economic considerations require that a relatively low-cost raw material be used for its production. An investigation into the use of a new, alternative substrate – pineapple waste – is described. This approach enables the utilization of the pineapple's (Ananas comosus) peels and core, which are usually discarded during the processing or consumption of the fruit. Using physical and enzymatic treatments, the waste was saccharified, and the resulting substrate was fermented with Saccharomyces cerevisiae for 7–10 days under aerobic conditions at 25 °C. This resulted in an alcohol yield of approximately 7%. The alcoholic medium was then used as a seed broth for acetic fermentation using Acetobacter aceti as the inoculum for approximately 30 days at 32 °C to obtain 5% acetic acid. Samples were analyzed at the beginning and end of the acetification cycle to assess the volatile and fixed compounds by GC–MS and UHPLC-QTOF-MS. The metabolomic analysis indicated that L-lysine, mellein, and gallic acid were significantly more concentrated in the pineapple vinegar than in the original wine. Higher alcohols, aldehydes, and ketones characterized the aroma of the final pineapple vinegar, whilst off-flavors were significantly reduced relative to the initial wine. This study is the first to highlight the metabolite profile of fruit vinegar with a slight floral aroma profile derived from pineapple waste. The potential to efficiently reduce the post-harvest losses of pineapple fruits by re-using them for products with added food values is also demonstrated.

Una rondine non fa primavera

Industria alimentare. Rischio esplosioni polveri

A new type of agglomerated cork stopper, generically called "micro-granulated cork stopper" or "micro-agglomerated cork stopper", is increasingly widespread on the wine market. It is identified by each cork factory with different names and is defined by the ISO 633:2007 as "agglomerated cork stopper-treated cork". It is a "stopper obtained by agglutination of cork granulates grain size between 0.25 and 8 mm, with addition of an adhesive and having at least 51% of cork granulate by mass”. Despite the alarming news that sometimes occur on food contamination by substances released to wine from these type of closure, no scientific reports have been done till now to detect the extent of the problem. This work aims to evaluate both the sum of all substances (Overall Migration - OM) and the individual molecules (Specific Migration - SM) that are able to be transferred from micro-granulated cork stoppers under specific time-temperature conditions and different simulant solutions as stated by the EC Regulation 10/2011, DM 21/03/1973, and ISO 10106:2003. Replicate migration trials involved samples of micro-granulated cork stoppers and natural cork stoppers (as controls) that were both fully immersed (worst conditions) in simulant solutions and put in contact only with one stopper face (real conditions). Molecule identification was carried out by means of target and non-target MS analysis coupled with UHPLC system and MS-Q-TOF detector (UHPLC/Q-TOF). Results highlighted variable values for OM and SM according to the test conditions including contact time, temperature and test medium (type of simulant solution). OM and SM limits (OML and SML) were exceeded by few samples of micro-granulated cork stopper under worse conditions than those of foreseeable use for closing and storing bottled wines.

This study optimized clarifying Muscat blanc must with either Ca- or Na- bentonite and related mixes in a dose range of 10÷100 g/hL through a central composite design. Response surface methodology (RSM) estimated the combined effect of the bentonite type and dose on free (i.e., aglycons) and glycosylated aroma compounds. Heat stability, turbidity, and color were further analyzed. Results indicate that Na-prevalent bentonite mixes significantly reduced the must haziness, while mixes with 50% Ca-bentonite or higher led to negligible decreases. The surface plots from RSM predicted that aglycons of aroma compounds were removed by Na-bentonite at lower doses and by Ca-bentonite regardless of the dose. Further, the model estimated the removal of glycosylated aroma compounds, especially by Ca-prevalent bentonite at 50 g/hL. Despite the study’s experimental limitations, these outcomes will help the enological sector improve aromatic sparkling wine production.

Nuove ATEX e sicurezza intrinseca

Legge 166 del 19 agosto 2016

Ricerca e tecnologia alimentare

Bentonite is used in oenology to improve the limpidity and the stability of wine and to predict the formation of deposits in the bottle. The exchangeable cations in its lamellar structures strongly influence some properties, such as the specific surface, the exchange capacity and the adsorption behavior. The unintended use of bentonite for juice settling and/or for wine fining produces jeopardized effects on colloidal and protein stability, the aroma compounds and sensory profiles. The interactions with haze-forming proteins, other colloids, as well as aroma compounds and phenols would have been to discover as the modulation of wine colloids by an adjuvant severely affects the wine resilience and the sensory profile. This chapter reviews several studies that focus on the impact of commercial bentonite samples used for both juice clarification and wine fining on the colloids, proteins, phenols and aroma compounds of white and red wines. Some parameters of practical value, such as the wine heat stability, the concentrations of total and haze-forming proteins and the content of the most relevant aromas, have been assessed to track the effects of bentonite and to achieve findings that are applicable to the field of oenology.

This work planned the fining of a oxidized Roero Arneis with 1 g L-1 of three different bentonite labels. The wine was spiked with amounts of 4-ethylphenol (4-EP) and 4-vinylphenol (4-VP) over the sensory threshold and levels of BA close to concentrations that can cause negative physiological effect. The elemental analyses of bentonite samples were conducted with an energy dispersive X-ray detector coupled to a scanning electron microscope. The surface charge density, the specific surface area (SSA), the pH and the swell index were measured using the methods described by O.I.V. and International Enological Codex. 4-EP and 4-VP, BA and o-quinone concentrations were determined in wine before and after fining through UPLC-MS methods.

This study focuses on the impact of one Na-bentonite and one Ca-bentonite for the clarification of ‘Muscat blanc’ must before ‘prise de mousse’. The clays were used both individually and mixed together at amounts ranging from 10-100 g hL-1 as modelled by Central Composite Design. The heat-stability of colloidal matter, the concentration of total proteins and the content of the free- and glycosylated-terpenols of treated and control samples were assessed through O.I.V. methods, HS-SPME-GC-MS techniques, and UPLC-MS approaches.

The aim of this work was to evaluate and compare the impact of three different types of winemaking of Fumin grapes in which the individual or combined effects of pre-fermentative and post-fermentative maceration, barrique and steel aging, malolactic fermentation and microoxygenation were tested. The sensory profiling of the wines obtained as well as the changes occurring in the chemical composition, colour parameters, polyphenol and aroma compounds, volatile phenols and biogenic amines were determined according to O.I.V. methods and metabolomic approaches thorough UPLC-MS.

L’acido tartarico è un acido organico naturalmente presente nell’uva e si ritrova nel mosto e nel vino sottoforma di sale di potassio, di calcio o come tartromalato di potassio. Di queste possibili forme, la più abbondante è quella del bitartrato di potassio che, come noto, presenta ridotta solubilità in mezzo alcolico e, pertanto, è suscettibile di precipitazione, con formazione di un deposito salino sul fondo della bottiglia. Lungi dall’essere percepito positivamente dal consumatore, questo aspetto naturale del vino viene affrontato nelle fasi precedenti all’imbottigliamento, con tecniche di cristallizzazione indotta in sistemi sia in continuo, sia in discontinuo. Questo articolo riporta i risultati e le conclusioni di un recente studio mirato alla comprensione del ruolo svolto da alcuni elementi della matrice vino sui meccanismi di precipitazione tartarica. Il ruolo protettore dei colloidi del vino sulla stabilità tartarica è noto da tempo ed è la ragione principale per cui i trattamenti di fining vengono condotti nella fase precedente a quella di stabilizzazione tartarica vera e propria. Sulle relazioni delle singole componenti colloidali del vino nei confronti del bitartrato di potassio ci sono però poche informazioni. Dai risultati raccolti, si evince che il rapporto quantitativo tra proteine e tannini, oltre ad influenzare l’organizzazione dei colloidi nella soluzione, ha influenza diretta sulla capacità dei cristalli di bitartrato di potassio di accrescere, in misura e secondo meccanismi diversi.

A new and sustainable cereal bar (named SOcrock) was created in the context of EcoTrophelia, an European competition originated from the EcoTroFood project (from the European Commission's Competitiveness and Innovation Framework Programme) and dedicated to student teams for creating prototype of food products with quality and environmentally friendly aspects. The designed product recipe consisted only of white sorghum, powdered grape seeds, honey, and dark chocolate. This essential composition was formulated in order to boost nutritional added value such as presence of polyphenols, high fiber content, low level of sodium, and a low caloric intake, all within an organic product, free of gluten and preservatives. A selected variety of white sorghum was the basic ingredient of the product: versatile, with nutritional properties similar to corn, sorghum has lower water requirements and withstands high temperatures brilliantly. In this product sorghum was transformed and used in three forms: as blown grain, as syrup (obtained by enzymatic hydrolysis of the grains) and as fiber (by-product of syrup production). Further innovation was the direct inclusion of grape seeds (by-products from distillery) that represents a simple solution for the recovery of low cost bio-active compounds. The preparation of the finished product was obtained by a semi-industrial processing line consisting in a cooker equipment (with hollow space in a diathermic oil bath) complete of planetary system and overturning head, cooling tunnel, and heat sealing packaging machine. The product impact on the ecosystem in terms of greenhouse gas emissions, water use, and exploitation of natural resources was evaluated. It resulted in a Type II environmental label which highlighted the product always falls in the best categories for sustainability. The developed product was awarded the bronze prize at the 2013 EcoTrophelia European final.

Many confectionery companies employ semi-finished lipid products, such as nut pastes, as an ingredient for the preparation of several foods. Nevertheless, during the storage, nut pastes have some drawbacks due both to the onset of rancidity, both to the separation between oil and semi-solid phase. The development of stable semi-finished walnut products in form of powder would allow to extend the walnut use in various preparations by increasing their convenience. As is well known, walnuts are highly nutritious fruits with well evidenced health benefits. In spite of natural antioxidant content walnut kernels are rich in polyunsaturated fatty acids and vulnerable to oxidation. In order to preserve thermo sensitive substances, a freeze-drying (lyophilizing) technique was developed by addition of polysaccharide matrices (including dietary fiber) in a walnut paste obtained by roasted kernels. This study aims to provide information on the impact of technological treatments and ingredient combinations on oxidative stability of freeze-dried walnut products. In preliminary tests, kernels were roasted at 110 °C for 5 min, 10 min, and 15 min. Residual moisture, pH and total acidity, peroxide value, and polyphenol contents were measured, as quality evaluation, in order to select the optimum operating conditions for the paste preparation. Optimal paste was obtained by milling 10 min roasted kernels, as it ensured a low residual humidity without affecting peroxides and polyphenols. Water and different combinations of maltodextrins DE12, tragacanth gum, and barley betaglucan were added to optimal walnut paste by creating emulsions which were then lyophilized. Quality evaluation was carried out on samples before and after freeze-drying treatment, and on freeze-dried products after 7 day, 60 °C storage. The formulation, containing maltodextrin and tragacanth gum, supplemented with betaglucans (at a ratio of 1:100 with the optimal walnut paste), showed no differences in the values of

To reduce the production surplus of grapes in the wine industry and, at the same time, to meet the growing de- mand of nutritious foods by health-conscious consumers, alternative processes with better sustainability are needed. In the production of colored grape juices for direct consumption, the application of heat on crushed grapes is a possible technology to increase extraction of anthocyanins and other phenolic compounds. To achieve this aim, three different thermal treatments were performed on crushed grapes of two different red varieties with peonidin or malvidin prevalence in the anthocyanin profile. Qualitative and quantitative differences in the chem- ical composition and color characteristics of the juices were evaluated to pinpoint the time–temperature combi- nation that allowed the highest extraction of anthocyanins. Furthermore, the modification of skin mechanical properties during thermal treatment and impact of the peonidin/malvidin ratio on juice color were investigated. The use of high temperatures for short times was the most profitable time–temperature combination based on the extraction efficacy, color stability and energetic requirements.

Microwave-assisted extraction (MAE) was investigated for recovering of total phenolic compounds from dried waste grape skins using a domestic microwave oven. Influence of vessel geometry, irradiation cycles, irradiation power and time was investigated. The results in terms of phenolics yield, antioxidant capacity and energy consumption were compared with a reference solid-liquid extraction (SLE) carried out for 2 h at 60°C. Equivalent yield of total phenolics as in SLE was achieved with a MAE extraction time of 1,033 sec (corresponding to 83 sec of irradiation at 900 W, 83% saving in extraction time compared to SLE and with a 70% energetic efficiency). Pre-maceration of samples and solvent pre-heating are proposed for large-scale industrial processes to enhance phenolics extraction and process efficiency.

The alarming scenarios of food crisis for growing population, shortage of raw materials, food and natural resources, jointly with the problem of pollution, have direct attention to find alternative resources. The waste utilization from the agro-food industry is a major challenge to reduce food losses, to increase the sustainability of food production and, therefore, increase food security, especially in developing countries. The objective of this research is to get vinegar from pineapple waste by means of: A1) Enzymatic hydrolysis: the saccharification of pineapple peels and core is examined during laboratory- scale experiments in order to determine the optimal time-temperature conditions for cellulolytic, pectinolitic, and invertase enzymes. A2) Physical pre-treatments: microwave (MW), boiling (B), high pressure with pressure cooker (HPC) and with autoclave (HPA), aimed at altering the structure of the fibrous matrix, are tested in order to enhance the sugar yield of enzymatic hydrolysis. A3) Alcoholic fermentation: three strain of Saccharomyces cerevisiae, mixed either with Lactobacillus delbruekii or with Lactobacillus plantarum at 15-20-25 °C are evaluated in order to obtain different pineapple wines. A4) Acetic fermentation: Acetobacter aceti is added to each pineapple wine at 30 °C with air flow (volume/h): pineapple wine ratio from 2: 1 to 10: 1 on a pilot scale fermenter. Samples obtained from saccharification, alcoholic and acetic fermentation were analyzed for pH, total acidity, total soluble solid (TSS), sugars, acids, ethanol, and volatile compounds. A detailed characterization of vinegar was carried out through UHPLC-QTOF-MS.

This study is located in the within of a research devoted at processing wastes both in developing and in developed Countries, so reducing both environmental pollution and seasonal fruit losses. In particular, the full work intended to completely process pineapple wastes into vinegar which may be then used as dressing, food preservative, and disinfectant. The preliminary trials presented here deepened the first process step (i.e. the saccharification) and looked into the feasibility of producing the greatest yield of reducing sugars from peels and core of pineapples. Wastes were cut into thin strips, chopped in a mixer, and divided into samples of peel and core to which distilled water was added. For enhancing reducing sugar yield, physical treatments were arranged to disaggregate the fibrous structure followed by enzyme treatments to breakdown cellulose polymers and to hydrolyse sucrose. The optimal time-temperature conditions of each process step were searched for gaining the highest reducing sugars yield at the end of the saccharification. Cellulolytic enzymes were tested for 4-8-18-24 h at 30-40-50 °C, invertase addition was arranged, and amylolytic enzymes were evaluated. All determinations were done in duplicate and a factorial ANOVA with Tukey's test at p ≤ 0.05 was used to measure the significance of the differences among treatments. The conditions allowing the greatest reducing sugar yield were: the addition to 100 g of waste fresh weight (fw) of 0.025 mL of thermostable a-amylase before a 10 min treatment at 143.27 kPa followed by 24 h-50 °C incubation with 0.05 g pectinase/kgfw, 6 g cellulase/kgfw, 1 g hemicellulase/kgfw, and 0.05 % glucoamylase and pullulanase (Venzyme/kgfw). Then, samples were incubated with 0.05 g invertase/kgfw for 3 h at 50 °C. Under these conditions, more than 100 g of reducing sugars per kg of fresh peels and about 330 g of reducing sugars per kg of fresh core were obtained.

Proteases are protein digesting biocatalysts long time used in the food industry. Although many authors reported the crystallization of papain and chymopapain from papaya latex, the powder of crude papain had the largest application as food supplements due to its highly positive effect on the degradation of casein and whey proteins from cow's milk in the stomach of infants. As the industrial preparative procedures have not been extensively applied, this study aims at producing dehydrated crude papain from fresh papaya pulp, planning lab-scale trials, followed by process development toward the pilot industrial-scale. In the lab-scale experiments, the enzyme activity (EA), expressed as protease unit (PU) /g, were evaluated on pulp and papain standard before and after a 2 h thermal treatment at 70 °C, 90 °C, and 120 °C, and the thermal behavior was monitored by means of differential scanning calorimeter (DSC). The process development toward the pilot-scaling optimized: the homogenization of the fresh pulp, followed by its filtration at high pressure (HP) in order to obtain the vegetation water and the pre-dehydrated pulp which was then oven dried varying the time-temperature conditions (4 h-80 °C; 2 h-120 °C; 30 min-150 °C). Proceeding at higher temperatures for a shorter time allowed obtaining commodity-related and technologically valid products. In the final pilot-scale step, filtration was done with vertical HP filter press, and final dehydration was performed with 2-step turbo-drying: the first aimed to concentrate with 2 min air flow (500 m3/h) at 200 °C, the second aimed to dry with 10 min air flow (500 m3/h) at 120 °C. The resulting dehydrated pulp was grinded with ball-mill to obtain a stable powder. Starting from 90±2 % pulp moisture, the two turbo-drying steps lowered the water content from 75±4 % to 50±2 % and from 50±2 % to 8±1 %, respectively. The enzyme release from the final powder highlighted an EA of the food-grade crude papain powder extract of 28 PU

The objective of this study was to produce maltodextrins (MD) and glucose syrup (GS) throughout a smallscale process from the direct conversion of cassava roots collected in Burundi and previously detoxified. The detoxified cassava slices were blended with water at ratios of 1:1.0; 1:1.3; 1:1.6. Then, the cassava mash was undergone previously to gelatinization and then to liquefaction experiments aimed at obtaining MD with a Dextrose Equivalent (DE) value < 20. The doses of 0.013, 0.016, 0.019, 0.025, and 0.075 % (venzyme/wfresh mash) thermostable a-amylase (Liquezyme-X) were investigated to be added to cassava mash at pH 6.5 before and after 10 min - 90 °C step at atmospheric pressure (patm) or 143.27 kPa (110 °C) allowing the starch gelatinization. Then liquefaction times of 10, 15, 20, 30, 40, 45, 60, 90 and 120 min were tested. The saccharification step followed the liquefaction in order to obtain a GS with DE close to 99. The hydrolyzed cassava mash from liquefaction experiments was added at pH 5.4 and 60°C with 0.019 % (venzyme/wfresh mash) glucoamylase (Dextrozyme GA) and pullulanase (Dextrozyme GX) testing 1, 2, 4, 6, 18, 24, and 48 h incubation times. All experiments were done in duplicate and analysis of variance (ANOVA) with Tukey's test at p=0.05 was used to measure the effect of changing variables among treatments. Correlation Pearson's test were applied to measure the strength of the interactions between the variables. Results showed that the 10 min-143.27 kPa (on lab-scale) and the 12 min-145÷152 kPa (on small-scale) burst of starch granules in 1:1.6 cassava: water mash with 0.013 % (venzyme/wfresh mash) thermostable a- amylase at pH 6.5 followed by 15 min-90 °C liquefaction phase at patm allowed at obtaining MD with DE value < 20. In order to gain a GS having a DE value close to 99, a 4 h-60 °C saccharification phase at pH 5.4 with 0.019 % (venzyme/wfresh mash) glucoamylase and pullulanase should be carried out. Finally, highly significant correlatio

The effects of industrial processing, product parameters (lethality F10 100 and Brix) and storage (up to 24 months at Troom) on the content and antioxidant capacity (AC) of the bioactive compounds in industrial tomato sauce were studied. The total phenolic content (TPC) of both the hydrophilic and lipophilic fractions (using the Folin-Ciocalteu assay and a direct absorbance reading at 280 nm), in addition to the lycopene content and AC (using the ABTS+ assay), were analysed. Statistical analysis showed that the content and activity of the studied bioactive constituents were positively influenced by the Brix but not influenced by the thermal treatment severity (up to 40 min as F10 100 ), that the TPC and its AC did not vary during storage, and that the lycopene AC decreased by 30% in the first year and then remained constant. The lycopene fraction and the hydrophilic fractions contributed 83% and 27%, respectively, of the sauce AC.

This study has been realized under a national project Valorvitis focused on the valorisation of wine making by-products for the production of high added-value compounds. The aim of this work was to investigate the possibility of recovering sugars as hemicelluloses hydrolysates suitable for bioethanol production. The production of hemicelluloses hydrolysates from stalks of six different grape cultivars was studied to assess: the cultivar influence on the recovery of non-structural sugars in the washing pre-treatment step; the influence of the cultivar and of the liquid/solid ratio in the acid hydrolysis step on the recovery of structural sugars; and the cultivar influence on the content of sugars degradation products(5-HMF, furfural and 5-MF), total phenols (based on Folin index), phenolic acids (by HPLC) and minerals in the hydrolysates (since these compounds could positively or negatively influence fermentation processes). The applied process consisted in a washing pre-treatment, followed by a dilute acid hydrolysis step (2 % sulfuric acid with two different solvent-to-solid ratios (10:1 and 20:1). The pre-treatment allowed to recover from 4.7 to 6.8 gGlucose+Fructose)/100 g dm depending on the cultivar, but in very diluted liquors (< 5 g/L as Glu+Fru). The 10:1 ratio was selected for the hydrolysis, since allowing for almost the same xylose yield as for the 20:1 ratio (from 4 to 7.4 g/100 g dm depending on the cultivar), the liquors contained lower amounts of phenolic compounds and sugar degradation products. The antioxidant activity (based on the radical ABTS test) of the hydrolysates (which could have an inhibitory effect in fermentation) was slightly influenced by the cultivar but not by the solvent to solid ratio. For all the cultivars, mineral analysis showed a certain content in micro and macronutrients that could positively influence a hypothetical fermentation process for bioethanol production. Therefore, the applied process could be optimized in order to

The growing lacking of raw materials and of water resources highlights the need to find alternative sources to supply global food needs, both in developed and in developed. If the search for new resources would start from developing countries, a double objective would be reached: to find resources on a global level and to promote the development of local populations. The study, which aims to produce a baked product using ingredients found in Burundi (flour, cereals and legumes, papaya and avocado fruit, avocado oil), suggests that, in addition to sensory pleasantness, a nutritional composition can also be reached according to UN guidelines for the realization of biscuits for emergency food situations. Furthermore, the results obtained from a preliminary approach to fortify some flour, confirm the success of this technique in the integration of mineral components.

The mechanisms and occurrence of aroma depletion during wine fining is still not clear. Previous results of our group led to hypothesized that some odor-active compounds were removed through direct adsorption mechanism on the clays without the involvement of any wine macromolecules. This paper examined the adsorption isotherms at 17±1 °C of some volatile compounds, principally responsible of the fruity character of white wines, onto three bentonite samples. The bentonites were added in three different amounts to a model white wine “spiked” with eight odor-active compounds and in the absence of wine macromolecule. The elemental composition, the surface charge density, and the SSA of the clays were determined and differences were analyzed by Tukey’s test. The Langmuir and the Freundlich models were fitted to the adsorption data. The most experimental adsorption isotherms were robustly fitted by the Freundlich equation and evidenced differences in the adsorption intensity and capacity values for the tested odor- active compounds. The main interaction forces controlling adsorption appeared to be related more to the clay characteristics, than to the compounds properties: samples having a lower SSA value and a greater charge density per surface unit seemed to interact with most of the odor-active compounds primarily through physical mechanisms. Differently, the clay with a large SSA value and a low charge density per surface unit promoted stronger adsorptions that were probably driven also by chemical interactions especially for ethyl esters.

The identification of highly effective procedures that reduce the cyanogens contained in cassava roots which require no sophisticated equipment, and can readily be adopted by subsistence farmers is of tremendous importance. This study, which used cassava root samples collected in Burundi, included fermentation tests using both selected and native cultures at different temperatures for variable times. Moreover, drying procedures with and without fermentation were carried out. A factorial analysis of variance (ANOVA) showed that the detoxification was mainly affected by fermentation length and by the initial cyanogens content of the roots. When fermentation lasted 48 h and the initial cyanide level was lower than 300 mg/kg dry weight (d.w.), the detoxification was also found to vary based on the microorganism inoculated; Saccharomyces cerevisiae demonstrated the greatest effectiveness. In terms of drying conditions, a temperature of 60°C, even for a shorter duration of time (8 h), lowered the initial cyanide level by more than 90%. Finally, when dehydration followed fermentation, the pressed pulp showed a substantial reduction in cyanide content. By means of this last procedure, safe cassava was produced according to FAO/WHO amendments (10 mg HCN equivalent per kilogram flour), if the initial cyanide level of roots did not exceed 200 mg/kg d.w. Actually, the initial maximum total cyanide content was confirmed to be fundamental in order to obtain safe products in relation to processing method adopted.

In the case referred to in this survey, we have verified the possibility of using avocado oil, pure or mixed with olive oil, as an ingredient in the production of gianduja chocolate spreadable cream. The results achieved by such application show a high oxidative stability of the cream added with avocado oil, even if maintained in experimental conditions, lasting for several days, with high temperatures and in the presence of oxygen. This may be due to the presence of antioxidant compounds of the oil itself, or to a synergistic effect of the latter with the phenolic compounds of cocoa, bringing out the antioxidant and protective action on the lipid component. From preliminary tests carried out on small volumes it can be said, moreover, that tested avocado oil gives sensory features that distinctly characterize the spreadable cream, even compared to the one containing extra virgin oil from taggiasca olives, currently in use at Venchi S.p.A. Confirmation tests carried out on a larger scale (industrial or semiindustrial)are needed, particularly to provide for proper mixing and tempering stages, which have not been carried out yet under laboratory conditions.

Three different processes were investigated for the recovery of fermentable sugars from grape stalks: autohydrolysis at 121°C before and after a pre-washing step and acid hydrolysis (2% H2SO4w/w) after a pre-washing step. Moreover, optimal conditions of a charcoal-based purification process were determined by experimental design. All hydrolysates, with their corresponding synthetic liquors were used as fermentation substrates for the production of metabolites by the yeast: Debaryomyces nepalensis NCYC 1026. The main fermentation product was ethanol, where a maximum production of 20.84g/l, a conversion yield of 0.35g ethanol/g monomeric sugars and a productivity of 0.453g/lh were obtained from non-purified autohydrolysate liquor. In all cases, ethanol production and cell growth were better in non-purified liquors than in synthetic liquors. These results could be influenced by the presence of other sugars in the hydrolysates, with higher concentration in non-purified ones.

Farine di cereali africani sono caratterizzate per la loro composizione nutrizionale. Le deficienze sono compensate con tecniche di fortifcazione.

This study was aimed to investigate the influence of grape cultivar on the lignocellulosic fractionation of grape-stalks. A four-step process (a washing treatment followed by an acid hydrolysis, a basic hydrolysis and, finally, a basic bleaching) was applied to stalks obtained from six different red and white grape cultivars. The different stalks were compared in terms of chemical composition of raw material (moisture, ash, minerals, lipids, fiber, proteins and free sugars) and of the recovered fractions (washing, acid and basic liquors and final cellulose residues). Recovery yields for free and hemicellulosic sugars, antioxidant compounds and cellulose were calculated. The cultivar significantly influenced all the investigated parameters, without characteristic performances between red and white cultivars. This result will need to be taken into account in the development of an optimized biorefinery approach for a large-scale exploitation of grape stalks.

Encapsulationof aphenolic grapemarc extract toenhanceits lipid solubilityandantioxidant efficiency forapplication as a natural preserving agent of hazelnut pastewas investigated. Three nanoemulsion based encapsulation systems were tested: an oil/water nanoemulsion; a powder obtained by maltodextrin-assisted spraydrying of the previous and an ethanol/solid–lipid nanoemulsion (the third also applied to resveratrol for comparison). All the samplesweremixedwithhazelnut paste atdifferent phenolic concentrations (from1200toless than 10 ppm of gallic acid equivalents for the original and encapsulated extracts, respectively). An accelerated shelf-life test at 60 C was carried out until 59 and 98 days (for the original and encapsulated extracts, respectively) with peroxides valuemonitoring. Paste oxidation followed a first-order kineticsmodel and was significantly inhibited by extract addition. Encapsulation improved phenolic efficiency against lipid oxidation, by increasing extract dispersability in the paste and preserving the antioxidant activity, with the oil/water nanoemulsion resulting as the best system.

This work extends the concepts proposed in a previous research paper about the interaction between the aroma of two white wines and bentonites. Such previous results led to hypothesized that some odor-active compounds were removed through direct adsorption mechanism on the clays. As a consequence, this paper examined the adsorption isotherms at 17±1°C of three bentonite samples added in three different amounts to a model white wine without the presence of wine macromolecule. The clays were analyzed for the elemental composition, the surface charge density, and the specific surface area (SSA) and differences were analyzed by Tukey’s test. The analysis of variance (ANOVA) was used to demonstrate the significance of the bentonite on the aroma reduction. The Langmuir and the Freundlich models were fitted to the adsorption data. The most experimental adsorption isotherms were robustly fitted by the Freundlich equation indicating that, under the condition of the study, the adsorption process more frequently occurred with a heterogeneous energy distribution of an infinite number of surface active sites. Overall, the modeling prediction ability tested by the error on r2 in cross validation enhanced differences both among the odor-active compounds and among the clays. Samples having a lower SSA value and a greater charge density per surface unit seemed to interact with most of the odor-active compounds primarily through physical mechanisms. Differently, the clay with a large SSA value and a low charge density per surface unit promoted stronger adsorptions that were probably driven by chemical interactions especially for ethyl esters. For the tested odor-active compounds differences in the adsorption intensity and capacity depended mainly on the bentonite characteristics rather than on the properties of the substances.

The objective of the current study was to investigate the application of colloidal gas aphrons (CGA) as a potential low-cost technology for the fractionation of phenolic extracts obtained from off-skins fermented red grape skins with high sugar content. The trials were aimed to investigate the possibility of using CGA generated from the non-ionic surfactant Tween20 to separate phenolic compounds from non-phenolic compounds (minerals and sugars) and to fractionate different fractions of phenolic compounds (total phenols, cinnamic acids and anthocyanins). Separation tests were carried out in a 0.7 L flotation column investigating the effect of both the volumetric ratio CGA/extract sample and the molar ratio CGA/extract sample on both the recovery yields and the separation factor (the ratio between the concentration of a compound in the recovered aphron phase and in the discharged liquid phase). Results revealed the possibility of reaching high recovery yield even though with a poor selective fractionation of the different compounds present in the extract, with glucose and cinnamic acids showing the highest affinity for the aphron phase.