Effect of packaging film and antibrowning solution on quality maintenance of minimally processed globe artichoke heads

Active Packaging-Releasing System with Foeniculum vulgare Essential Oil for the Quality Preservation of Ready-to-Cook (RTC) Globe Artichoke Slices

Two globe artichoke genotypes, “Spinoso sardo” and “Opera F1”, have been processed as ready-to-cook (RTC) slices and refrigerated at 4 °C for 12 days (i) to evaluate the suitability to be processed as RTC slices; (ii) to evaluate the effect of a Foeniculum vulgare essential oil (EO) emitter, within an active package system, to delay quality decay, thus extending shelf life; (iii) to estimate the impact of EO emitter on the sensory profile of the RTC slices after cooking. Results revealed that both globe artichoke genotypes possess a good attitude to be processed as RTC product. “Opera F1” showed the best performances for color parameters, texture and chemical indexes, while “Spinoso sardo” showed lower mass loss (ML) over the storage time. The addition of EO emitter slowed down the consumption of O₂, better preserved texture when compared to the control and more effectively control polyphenol oxidase (PPO) activity and antioxidants’ retention during the cold storage. Microbial counts in control globe artichoke RTC slices were significantly higher than those packed with EO emitter, confirming the inhibiting role played by EO of F. vulgare. In addition, the EO emitter did not influence negatively the sensory profile of RTC globe artichoke slices after microwave cooking.

Packaging Solutions to Extend the Shelf Life of Green Asparagus (Asparagus officinalis L.) 'Vegalim'

The aim of the study was to assess, through a comparative shelf-life test, the suitability of two packaging materials, namely macro-perforated polypropylene (PP MA) and micro-perforated coextruded polypropylene (PP C), for the quality preservation of green asparagus (Asparagus officinalis L. 'Vegalim'). Quality of spears was evaluated during 30 days at refrigerated storage by monitoring chemical, physical, and enzymatic parameters as well as sensory descriptors. PP C kept headspace composition close to suggested values for fresh green asparagus. Total color difference increased during the storage and it was highly correlated with chlorophyll-a and carotenoids, however, sensory color perception did not change significantly until 22 days of storage. PP C maintained ascorbic acid concentrations close to the initial levels, limited total phenolic compound loss to 24% (45% in PP MA), determined an increase of 72% in fiber content and small changes in lignin value; enzymatic changes were significantly inhibited. Significant sensorial differences were detected after 22 days of storage, with PP C performing better than PP MA. PP C film was confirmed as the best choice, limiting weight loss and maintaining a fresh-like appearance during 30 days of storage, thus allowing an extension in postharvest life.

Shelf-life study of ready-to-cook slices of globe artichoke 'Spinoso sardo': effects of anti-browning solutions and edible coating enriched with Foeniculum vulgare essential oil

BACKGROUND

The globe artichoke [Cynara cardunculus var. scolymus (L.) Fiori] is a natural source of minerals, fiber, inulin, and polyphenols. A ready-to-cook (RTC) version of this product could improve its commercialization and consumption. In this study, the effects of (i) anti-browning treatments (citric acid 0.5% + ascorbic acid 2%, or cysteine 0.5%, w/v) and (ii) dipping in locust bean gum (LBG) edible coating with or without Foeniculum vulgare essential oil (EO) were evaluated on RTC globe artichoke slices cv. 'Spinoso sardo' during storage (11 days at 4 °C). Fresh weight loss, color, texture, polyphenol oxidase (PPO), microbiological and chemical parameters, antioxidant capacity, and sensory descriptors were determined.

RESULTS

The results showed that, despite the antioxidant treatment used, when EO was added to LBG, all microbiological groups underwent an average reduction of 0.50 log CFU g^-1 . Cysteine preserved the antioxidant capacity, color, and texture of samples better than citric acid and ascorbic acid, and inhibited PPO; the addition of EO to LBG enhanced these effects. At the end of the storage period, the overall highest sensory attribute score was attained by the coated globe artichoke samples with EO.

CONCLUSION

The marked efficacy of the LBG edible coating with added F. vulgare EO in maintaining microbiological, physical, chemical, and sensory qualities makes it a promising processing tool for the preservation of ready-to-cook Spinoso sardo globe artichoke slices during storage for 11 days at 4 °C. © 2019 Society of Chemical Industry.

Effect of nitrogen fertilisation on the overall quality of minimally processed globe artichoke heads

BACKGROUND

Although nitrogen (N) fertilisation is essential for promoting crop yield, it may also affect the produce quality. Here, the influence of three N fertiliser rates (0 kg ha^-1 as a control, 200 kg ha^-1 and 400 kg ha^-1 referred to as N₀ , N₂₀₀ and N_400, respectively) on the overall quality of minimally processed globe artichoke heads was investigated during refrigerated storage for 12 days.

RESULTS

Throughout the storage time, N fertilised samples had higher inulin contents than those unfertilised. In addition, the respiratory quotient of N₂₀₀ and N₄₀₀ samples was 2-fold and 2.5-fold lower than N₀ ones, whose values were close to the normal range for vegetables. All the samples reported good microbiological standards, although N₂₀₀ and N₄₀₀ achieved lower mesophilic and psychotropic counts than N₀ throughout the storage time. After 8 and 12 days of refrigerated storage, the N₂₀₀ samples showed the highest scores of positive sensory descriptors.

CONCLUSION

A fertiliser level of 200 kg N ha^-1 is suitable for obtaining minimally processed globe artichoke heads with good nutritional, sensory and microbiological quality, characterised by low endogenous oxidase activities. Proper packaging systems and procedures are, however, crucial for extending the product shelf-life and, thus, promoting its exportation on a wider scale. © 2016 Society of Chemical Industry.