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Background: While there has been an increasing interest in the health properties of chocolate, limited research has looked into the changes of antioxidants occurring in the time span from production to the best before date, which was a period of 18 months in this study. Methods: Humidity, ash, pH, acidity, fiber, carotenoids, retinols, tocopherols, sugars, proteins, theobromine, caffeine, polyphenols, fats, the peroxide value, organic acids, and volatile compounds, along with the sensory profile, were monitored at 18-week intervals for 18 months under conditions simulating a factory warehouse or a point of sale. Results: At the end of the storage period, more polyphenols were lost (64% and 87%) than vitamin E (5% and 14%) in cocoa mass and cocoa powder, respectively. Conversely, a greater loss in vitamin E (34% and 86%) than in polyphenols (19% and 47%) was shown in the hazelnut paste and gianduja chocolate, respectively. The sensory profiling of cocoa mass, cocoa powder, and hazelnut paste revealed increases in grittiness and astringency, as well as decreases in melting, bitterness, and toasted aroma. Moreover, in the hazelnut paste and gianduja chocolate, oiliness increased with a toasted and caramel aroma. Furthermore, dark chocolate was more gritty, acidic, and bitter. Milk chocolate lost its nutty aroma but maintained its sweetness and creaminess. Conclusions: These results should contribute an important reference for companies and consumers, in order to preserve the antioxidants and understand how antioxidants and sensory properties change from the date of production until the best before date.

Waste from fruits and vegetable processing industry is produced in large quantities worldwide and it con-tains high levels of lignocellulose, fibre, sugar, bioactive and functional compounds. Their utilisation has become one of the main important and challengeable aspects due to the generation of large quantities of by-products including peels, seeds, leaves and unused flesh in different steps of processing chain. Many researches have validated the waste utilisation as novel, low-cost, economical and natural sources of diet-ary fibre, antioxidants, pectin, enzymes, organic acids, food additives, essential oils, etc. through different methods of extractions, purifications and fermentations. Though, obtaining these by-products from such a variable substrate requires an understanding of the composition of the polysaccharides and their associa-tions within the overall substrate. Focus on the pineapple fruit, scientific and technological studies have already highlighted and confirmed the potential of better and more profitable markets for pineapple wastes. This review is first of all the collection of previous reports about valorisation of food processing waste, deepening the possibilities of pineapple waste utilisation and to promote the integral exploitation of the by-products rich in bioactive compounds, even as multifunctional food ingredients. More in detail, this review aims at identifying those processes that can be implemented even in disadvantaged areas by means of technologies that allow recovering waste directly on site, thus reducing pollution and providing ingredients/food products with high nutritional values that could be integrated into the diet.

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.

L’utilizzo degli scarti da parte dell’industria alimentare costituisce una sfida importante per ridurre le perdite di cibo, aumentare la sostenibilità della produzione alimentare e, pertanto, incrementare la sicurezza alimentare specialmente nei paesi in via di sviluppo. Obiettivo della presente tesi è ottenere aceto dagli scarti dell’ananas tramite idrolisi enzimatica preceduta da pre-trattamento fisico, fermentazione alcolica con differenti ceppi di Saccharomyces cerevisiae, addizionati di Lactobacillus delbruekii o Lactobacillus plantarum del liquido saccarificato, e fermentazione acetica con Acetobacter aceti in un impianto pilota. I campioni ottenuti dalle prove di saccarificazione, fermentazione alcolica e acetica sono stati analizzati per pH, acidità totale, grado Brix, zuccheri, acidi organici, etanolo e per i composti volatili. Una caratterizzazione dettagliata dell’aceto è stata eseguita tramite UPLC/Q-TOF e GC-MS., Using waste from the 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 thesis is to get vinegar from pineapple waste by means of: enzymatic hydrolysis proceeded by physical pre-treatment; alcoholic fermentation of the saccharified juice with different strains of Saccharomyces cerevisiae and Lactobacillus delbruekii or Lactobacillus plantarum; acetic fermentation with Acetobacter aceti in a pilot plant. 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 UPLC/Q-TOF and GC-MS.

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

L’utilizzo degli scarti da parte dell’industria alimentare costituisce una sfida importante per ridurre le perdite di cibo, aumentare la sostenibilità della produzione alimentare e, pertanto, incrementare la sicurezza alimentare specialmente nei paesi in via di sviluppo. Obiettivo della presente tesi è ottenere aceto dagli scarti dell’ananas tramite idrolisi enzimatica preceduta da pre-trattamento fisico, fermentazione alcolica con differenti ceppi di Saccharomyces cerevisiae, addizionati di Lactobacillus delbruekii o Lactobacillus plantarum del liquido saccarificato, e fermentazione acetica con Acetobacter aceti in un impianto pilota. I campioni ottenuti dalle prove di saccarificazione, fermentazione alcolica e acetica sono stati analizzati per pH, acidità totale, grado Brix, zuccheri, acidi organici, etanolo e per i composti volatili. Una caratterizzazione dettagliata dell’aceto è stata eseguita tramite UPLC/Q-TOF e GC-MS., Using waste from the 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 thesis is to get vinegar from pineapple waste by means of: enzymatic hydrolysis proceeded by physical pre-treatment; alcoholic fermentation of the saccharified juice with different strains of Saccharomyces cerevisiae and Lactobacillus delbruekii or Lactobacillus plantarum; acetic fermentation with Acetobacter in a pilot plant. 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 UPLC/Q-TOF and GC-MS.

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.

Rispetto ad altre tecniche di conservazione di alimenti (essiccamento, sottovuoto o atmosfera modificata, aggiunta di conservanti, salagione, affumicatura, ecc.), la surgelazione garantisce una maggiore sicurezza sotto l’aspetto igienico-sanitario, un maggiore mantenimento della qualità originaria ottenuta con il minor impatto tecnologico sul prodotto, la shelf-life più lunga e la garanzia pressoché assoluta del rispetto delle caratteristiche fisiche, chimiche e organolettiche degli alimenti. Il surgelamento, infatti, è ormai riconosciuto come il metodo più “naturale” di conservazione: ha bisogno solo del freddo e non necessita di additivi. Con l'ausilio dei prodotti surgelati, inoltre, è più facile avere un'alimentazione completa e variata, la qual cosa è ritenuta oggi il sistema migliore per mantenere efficiente il nostro organismo e proteggerlo dallo stress della vita quotidiana.