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Nowadays, many foods are packaged in plastic bags and heat treated within its container. The goal of this study is to validate, sensory and physically, a PP/PA plastic bag for using with food and his following heat treatment. In heat treatment resistance test, distilled water was used as food simulant. Meanwhile, for the sensory test it was used the same simulant and potato (Solanum tuberosum) was the food example. Thermal resistance test was carried out at during 2hr at 70˚C and during 2hr at 100˚C. For the sensory analysis the heat treatment was performed at 100˚C during different analytical times: 2min, 6min and 8min. Global results show us, that not all bags can bear conditions at 100˚C during 2hr. In this situation, the package may have tears and losses in any of their joints. This fact contradicts the maximum conditions that manufacturer guarantees us (115˚C during 2hr). On the other test, there is a difference of 99 % confidence in the treated water flavorings at 100˚C during 8min. The potatoes begin to have a sensory defect from those same conditions: at 100˚C, 8min. In a sterilization heat treatment this plastic bag could accentuate these flaws in the food Avui en dia, molts aliments son envasats en bosses i tractades tèrmicament dins del envàs. L'objectiu d'aquest treball es validar, sensorialment i físicament, un envàs de plàstic de PP/PA para el seu ús amb aliments i un posterior tractament.Per a la prova de resistència tèrmica es va utilitzar aigua destil·lada com simulant alimentari. Però, a la prova d'anàlisi sensorial es va utilitzar aquest mateix simulant i patata (Solanum tuberosum) com a aliment model. La prova de termoresistència es va dur a terme a unes condicions de 2h a 70˚C i de 2h a 100˚C. Mentre que, per a l'anàlisi sensorial, el tractament tèrmic es van realitzar a 100˚C a diferents temps : 2min , 6min i 8min. Als resultats , es va obtenir que no totes les bosses aguanten unes condicions tèrmiques de 2h a 100˚C. En aquesta situació, l'envàs pot presentar fissures i pèrdues a algun dels seus punts d'unió . Això va contradir les condicions màximes del fabricant, en el què es garanteix una resistència de 2h a 115˚C. Per altra banda, hi ha una diferència del 99% de confiança en l'aroma de l'aigua tractada a 8min a 100˚C. Les patates comencen a tenir també un defecte sensorial a partir d'aquestes mateixes condicions, 8min a 100˚C. A condicions d'esterilització l'envàs podria accentuar aquests defectes en l'aliment. Hoy en día, muchos alimentos son envasados en bolsas y tratadas térmicamente dentro de su envase. El objetivo de este trabajo es validar, sensorialmente y físicamente, un envase plástico de PP/PA para su uso con alimentos y su posterior tratamiento. Para la prueba de resistencia térmica se utilizó agua destilada como simulante alimentario. En la prueba de análisis sensorial se utilizó este mismo simulante y patata (Solanum tuberosum) como alimento modelo. La prueba de termoresistencia se llevo a cabo a unas condiciones de 2h a 70˚C y de 2h a 100˚C, mientras que, para el análisis sensorial, el tratamiento térmico se realizaron a 100˚C a diferentes tiempos: 2min, 6min y 8min. En los resultados, se obtuvo que no todas las bolsas soportan unas condiciones de 2h a 100˚C. A esa situación, el envase puede presentar roturas y pérdidas en alguno de sus puntos de unión. Esto contradijo las condiciones máximas del fabricante en el que se garantiza una resistencia de 2h a 115˚C. Por otra parte, existe una diferencia del 99% de confianza en el aroma del agua tratada a 8min a 100˚C. Las patatas comienzan a tener un defecto sensorial a partir de esas mismas condiciones, 8min a 100˚C. A condiciones de esterilización el envase podría acentuar estos defectos en el alimento.

Six cling-stone melting nectarine cultivars (‘Big Top’, ‘Luciana’, ‘Honey Royale’, ‘Nectareine’, ‘Big Nectared’ and ‘Nectalady’) were cut and dipped into an aqueous solution of 2% ascorbic acid, 1% citric acid and 1% calcium chloride before being stored in amorphous polyethylene terephthalate trays. Their suitability to be processed as fresh-cut product was then investigated on the basis of their initial quality, browning potential and sensory attributes as well as the changes in these parameters after processing. At harvest, two maturity stages were selected for each cultivar based on their index of absorbance difference. Nonetheless, no significant effect of maturity stage at harvest was observed for most of the physico-chemical and/or sensory parameters during storage. On the contrary, differences among cultivars were emphasized when comparing ethanol and acetaldehyde production, polyphenol oxidase (PPO) activity, volatiles production, sensory profile, and consumer acceptance. ‘Honey Royale’ and ‘Nectalady’ wedges showed higher volatiles production, whereas ‘Big Nectared’ and ‘Luciana’ had a slightly lower browning index (BI). In the sensory evaluation, ‘Nectareine’ had the highest acceptability scores, whereas ‘Big Nectared’ had the lowest. The significant correlations between volatiles, sensory attributes and degree of liking observed in this study underline the importance of aroma in fresh-cut products.