Physical properties of Physalis peruviana L

Physalis (Physalis peruviana L.), also known as cape gooseberry or ground-cherry, plays an important role in nutrition as an excellent base for dietetic products. Highly valued for its unique flavour, texture and colour, recent research has shown that physalis fruit is rich in many beneficial compounds. In this study, the diameter and mass of physalis fruits were measured, which can be used to calculate other biometric characteristics of the fruit, such as: surface area, volume or density. Other physical properties were measured, namely the colour coordinates, by means of a Chroma meter, whilst the textural parameters firmness and elasticity were measured with a texturometer. The following values were calculated for the physalis fruits analysed in the present work: 1.69 cm for average diameter; 8.98 cm2 for surface area, 2.51 cm3 for volume; 2.77 g for mass was, and 1.10 g/cm3 for density. The colour coordinates were 56.72 for lightness, 16.69 for redness, and 58.11 for yellowness. Skin firmness and elasticity were evaluated for texture attributes, and their average values were 2.40 N and 2.94 mm, respectively. The results of this work are in accordance

Some factors that may affect the physical-chemical properties of blueberries

The aim of the present study was to investigate the effect of different production and conservation factors on some properties of blueberries. Among the production factors considered were cultivar (Duke, Bluecrop and Ozarkblue) and production mode (organic or conventional). Regarding the conservation factors were evaluated temperature (ambient or refrigeration) and storage time (0, 7 and 14 days). The properties under study belong to three categories: physical properties (color and texture); chemical properties (moisture content, sugars and acidity) and phenolic and antioxidant properties (total phenols, anthocyanins, tannins, ABTS antioxidant activity, DPPH antioxidant activity). The results revealed that moisture content was only influenced by cultivar and that both acidity and sugar contents varied according to the production mode used. Also it was evidenced that the antioxidant activity was not statistically different between cultivars, production modes or conservation conditions. Regarding the phenolic compounds, the tannins were significantly higher for the blueberries produced in organic agriculture. Regarding color significant differences were also encountered and the most intense blue was found in blueberries from cv. Duke, produced in organic farming and stored under refrigeration. Textural attributes were also very significantly influenced by all factors at study: cultivar, production mode and conservation, and the berries from cv. Duke stored under refrigeration showed the highest firmness.