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Baby lettuce leaves have recently been developed for the unwashed fresh-cut and ready-to-eat markets. The aim of this research was to characterize this product by sensory, physicochemical and microbiological analyses performed during storage at 4 and 10°C. Products were analysed at sampling times chosen on the basis of 5 sensory visual quality (VQ) levels. Samples scoring VQ5 and VQ4 were considered acceptable (Ac), whereas the remaining scores were defined as unacceptable (UAc). Each VQ level was then characterized for physicochemical (colour, ammonia, antioxidant activity, electrolytic leakage, phenols, chlorophyll, respiratory activity) and microbiological (total viable count, Pseudomonas spp, Enterobacteriaceae, lactic acid bacteria, yeast and moulds) parameters. UAc samples also proved unsatisfactory from a microbiological point of view (total viable count >=107 CFU/g). Partial Least Square (PLS) regression analysis allowed to identify colour change (?E*) and total chlorophyll (TC) as X-variables to predict the microbial load (TVC) (Y-variable) associated with each sensory VQ level. The model obtained showed R2CV=0.94, RMSECV=0.41 and a relative error of 5.61%. In conclusion, the use of these parameters as quality indicators could be a new strategy for discriminating green leafy vegetables into acceptable or unacceptable products.

Low oxygen controlled atmosphere was reported to be useful for fresh-cut broccoli raab cold storage in maintaining freshness and qualitative traits, whereas excessive accumulation of CO2 (10-15%) should be avoided. Starting from these finding the aim of this work was to individuate the proper modified atmosphere packaging (MAP) for fresh-cut broccoli raab in order to reach at the equilibrium the target atmosphere composition with low oxygen (3%) during cold storage. Broccoli raabs harvested from a commercial farm, were selected for defects and were cut from the stalks, obtaining the ready-to-use product. After washing the product was packaged in plastic trays sealed in bags of different plastic materials. Two commercially available polymeric coupled films (polypropylene/polyethylene terephthalate, PP/PET, and polypropylene/polyamide, PP/PA microperforated, MF), were used as packaging materials with or without the inclusion of a CO2 absorbers (used in 5-g sachets). For each packaging condition a passive (P-MAP) and an active atmosphere with 5% O2 in nitrogen (A-MAP) were used. Unpackaged samples were used as control and stored with all packages at 5 °C. Initially, and after 3 and 8 days samples were taken and quality attributes (overall appearance, odor, color analysis and weight loss) were evaluated. Gas concentrations (O2 and CO2) inside packages were also monitored. Among the packaging treatments tested the combination using PP/PA in A-MAP with the use of CO2 absorbing sachets reached equilibrium condition very close to optimal for broccoli raab. Fresh-cut broccoli raab stored in this condition for 8 days showed negligible reduction of appearance and odor scores, compared to the fresh samples resulting significantly higher than for the samples stored in all other packaging combinations.

Male zucchini flowers (Cucurbita pepo L.) are greatly appreciated by consumers although, due to their high perishability, they are destined only to local markets. The effects of four different atmosphere compositions (air, 3% O2 in nitrogen, 3% O2 + 10% CO2 in air, and 10% CO2 in air) on quality attributes of fresh male zucchini flowers (color, weight loss, respiration, fermentative volatiles, and vitamin C) were studied. Storage in controlled atmosphere significantly (P

Fresh convenience products represent a category of minimally processed fruit and vegetables (chunks, mousse, smoothies) that respond to the changes in consumer attitudes. Thanks to the image of convenience (time-saving, snack sizes, no waste, smart packaging) and healthiness their sales are steadily increasing. In this study 26 varieties (including peach, nectarines, and clingstone peaches) from Apulian production were divided into three groups according to harvest dates in early (A), middle (B) and late (C) maturing. Physical, chemical and sensorial analyses were performed in order to select high quality fruits for minimal processing according to the harvesting season. A multivariate Principal Component Analysis was applied to discriminate different varieties for quality attributes. Within Group A, ‘Honey Kist’ showed the lowest acidity and intermediate susceptibility to mechanical damage. For Group B, ‘Stark Red Gold’, ‘Zee Glo’ and ‘Venus’ resulted different in sensorial evaluation, while ‘Loadel’ and ‘Eolia’ were more susceptible to browning. For Group C, ‘Tardi Belle’ and ‘Baby Gold7’, although more sensitive to mechanical damage, were differentiated for flavor. Results of this work confirm the extreme variability among varieties in terms of sensorial quality, susceptibility to browning and to mechanical damage, and the importance of assessing varietal screening for selection of most suitable varieties for minimal processing., Advances in Horticultural Science, Vol 26 No 1 (2012)