Search results for "browning"
showing 10 items of 61 documents
Influence of the functionalisation of mesoporous silica material UVM-7 on polyphenol oxidase enzyme capture and enzymatic browning
2020
Polyphenol oxidase (PPO), also known as tyrosinase and catechol oxidase, is the enzyme responsible for enzymatic browning in foods. It causes undesirable organoleptic, nutritional and colour changes. Here, we report the preparation of five nanomaterials and a study of their ability to modulate PPO enzyme activity. The materials consist of UVM-7 supports (a mesoporous silica material) modified with diverse functional groups (i.e. amine, carboxylic acid, isocyanate, alkane and pyridine). We also studied the PPO immobilisation capability of the materials. All the materials, except the carboxylic acid functionalised one, offer high PPO loading capabilities and the immobilisation speed increases…
POLYPHENOL OXIDASE ACTIVITY FROM THREE SICILIAN ARTICHOKE (CYNARA CARDUNCULUS L. VAR. SCOLYMUS L. (FIORI)) CULTIVARS: STUDIES AND TECHNOLOGICAL APPLI…
2010
Several papers helped with the development of more methods to control browning, or study thermal polyphenol oxidase (PPO) inactivation, but did not provide any solutions to technological process problems and food process improvement. Artichokes [ Cynara cardunculus L. var. scolymus L. (Fiori)] are susceptible to browning; this alteration could affect and reduce the suitability for its use, fresh or processed. Within this study, the catecholase and cresolase activities of PPO from three different Sicilian artichokes cultivar were characterized with regard to substrate specificity and enzyme kinetics, optimum pH and temperature, temperature and pH stability, and inhibitor test; all of the res…
OXIDASES ACTIVITIES AND ANTIOXIDANT CAPACITY OF MINIMALLY PROCESSED BABY ROMAINE LETTUCE (Lactuca sativa L. CV. DUENDE) CULTIVATED UNDER DIFFERENT SA…
2007
[SPA] El pardeamiento enzimático es uno de los principales problemas implicados en el procesamiento mínimo y en la siguiente conservación de hortalizas de hoja, reduciendo la vida comercial del producto. Se han evaluado las variaciones de las dos principales oxidasas, polifenol oxidasa (PPO) y peroxidasa (POD), así como del contenido en fenoles, del color y de la capacidad antioxidante (metodo ORAC) durante 10 días de conservación a 4 °C de lechuga Baby Romaine (Lactuca sativa L. cv. Duende) mínimamente procesada, cultivada bajo 3 distintas condiciones de salinidad (2,8, 3,8, 4,8 dS/m), para determinar la condición más apta al siguiente procesamiento. Niveles crecientes de salinidad redujer…
EFFECT OF PASSIVE ATMOSPHERE AND CHEMICAL TREATMENT ON FRESH CUT OF WHITE-FLESH PEACH CULTIVAR 'SETTEMBRINA DI BIVONA'
2015
Peach germplasm in Italy includes white- and yellow-flesh peaches, all of them characterized by a persistent aroma and an excellent flavor. However, their behavior, in terms of postharvest maintenance and suitability for minimal processing, has never been investigated. The aim of this study was to investigate the effects of passive atmosphere and chemical treatment, with 2% ascorbic acid and 1% calcium lactate, in order to prevent fruit browning and to maintain the quality of fresh cut slices of the white-flesh peach cultivar ‘Settembrina di Bivona’. To achieve a passive atmosphere condition, approximately 150 g of peach fruit slices were placed in rigid bi-oriented polystyrene bags and sto…
Use of xanthan gum and calcium ascorbate to prolong cv. Butirra pear slices shelf life during storage
2023
After cut, pear fruit (Pyrus communis L.) during shelf-life can be subjected to colour and flavour changes. To maintain flesh colour and firmness, different technologies could be employed during shelf-life, such as chemical, physical and edible coating treatments. In the present study, the effects of two edible coating formulations containing xanthan gum and calcium ascorbate on fresh-cut pear fruit were investigated. After harvest, 200 fruits were cut and coated with Xanthan Gum (XAN) and distilled water or Xanthan gum + Calcium Ascorbate (ASC), respectively, while control (CTR) pear fruit slices were soaked in distilled water and lastly packed in polyethylene terephthalate (PET) packages …
Effects of combinational use of controlled atmosphere, cold storage and edible coating applications on shelf life and quality attributes of fresh-cut…
2022
Abstract Background Persimmon fruits are cherished for their unique flavor and high nutrient content. In the present study, the effects of Aloe vera-based edible coatings (EC) added with 1% ascorbic acid, 1% citric acid and 5% calcium chloride in modified atmosphere packaging (MAP) and their impact on shelf-life quality of fresh-cut persimmon fruit, were investigated. The experimental design consisted of four treatments 1) Aloe vera edible coating + modified atmosphere packaging (EC + MAP), 2) untreated fruit packaged with MAP (CTR + MAP); 3) Aloe vera-based edible coating in passive atmosphere (EC PASSIVE); 4) untreated fruit in passive atmosphere (CTR PASSIVE). Persimmon fruit were stored…
Use of xanthan gum as edible coating to prolong shelf life of cactus pear fruit
2022
The objective of this work was to elucidate the effect of xanthan gum-based edible coating C35H49O29 on the quality of cactus pear fruit (Opuntia ficus-indica). The research was conducted in 2018, on O. ficus-indica ‘Bianca’ fruit, coming from second bloom “scozzolatura”. After harvest, 100 fruits were coated with a xantan gum (XAN) and distilled water and on other 100 fruits were immersed in distilled water (CTR). All fruits were stored at 6±0.5°C with RH 90% for 30 days. Every 7 days, visual quality browning index score, flesh colour, total soluble solids (TSS), total acidity (TA), ascorbic acid and total phenols were measured. During cold storage, fruit treated with XAN (p<0.05) showe…
Effect of grafting, cultivar and cold storage on eggplant fruits
2011
Eggplant is a perishable fruit that, once harvested, can be stored at 10 °C for several days. If long stored, fruits reduce their texture, skin brightness and become rubbery. Recently, grafting onto Solanum torvum has become more and more used to give resistance to biotic and abiotic stresses. The aim of this work was to study the effect of grafting, cultivar and cold storage on post-harvest changes of eggplant fruits. Grafted or ungrafted plants of four cultivars were grown in an unheated greenhouse during autumn-spring period. Three cultivars had skin with very dark purple colour (Black Bell, Black Moon and Longo) and one had skin with unhomogeneous light purple colour (Birgah). After har…
Effects of an innovative dipping treatment on the cold storage of minimally processed Annurca apples
2007
The effect of trehalose as an edible coating on minimally processed Annurca apple slices was studied during cold storage. The edible coating was prepared by dipping the fruit in a solution containing trehalose at 0.8%, sucrose at 1.0% and sodium chloride at 0.1%. During storage at 6 degrees C the following parameters were monitored: weight loss, colour (hue angle (h degrees) and whitening index (WI)), firmness, malic and ascorbic acids, polyphenol content.. microstructure by scanning electron microscopy (SEM) and microbial count. The results showed that such a coating reduced the browning phenomena; in fact the WI and h degrees values were significantly lower in coated samples than untreate…
SENSORY EVALUATION AND SUITABILITY FOR FRESH-CUT PRODUCE OF WHITE PEACH [PRUNUS PERSICA (L.) BATSCH] 'SETTEMBRINA DI BIVONA'
2015
âSettembrina di Bivonaâ peaches were cut into slices to assess their suitability as fresh-cut produce. Untreated (control) and treated with calcium lactate fresh cut slices were closed in plastic boxes for 24 hours (T1) or five days of storage (T2) at 5°C, and then placed at 20°C to assess consumersâ liking. Soluble solids content, titratable acidity, firmness and pH were measured. A sample of n = 750 consumers was selected taking into consideration three variables: age (from 25 to 55 years old), professional status (employed) and aptitude to buy fresh-cut fruit for personal use. A systematic sampling was used, with a detection point based in a properly selected supermarket during t…