Influence of storage on the volatile profile, mechanical, optical properties and antioxidant activity of strawberry spreads made with isomaltulose

Impact of sugar replacement by non-centrifugal sugar on physicochemical, antioxidant and sensory properties of strawberry and kiwifruit functional jams

Raw cane sugars have been claimed to be rich in natural phenolic compounds which, in contrast to refined sugar, may increase the nutritional value of foods and contribute to the development of healthier foods and diets. The use of non-refined cane sugars in food formulation seems an interesting option since they provide natural antioxidants with sucrose still being the major sugar present, minimizing the loss of technological properties. However, substitution of refined sugar could imply an undesired impact on physicochemical and sensory properties, conditioning consumer's acceptance. Functional jams (strawberry and kiwifruit) with a larger fruit to sugar ratio than conventional ones, in which white sugar was replaced by granulated jaggery (0, 15, 30, 45, 60 y 75 % w/w) were obtained. Impact of sugar replacement was assessed by evaluating physicochemical properties (moisture, water activity, pH, total soluble sugars, sugar profile (glucose, fructose, sucrose), and optical, rheological, mechanical and antioxidant properties). Sensory properties and microbiological stability were also determined. Jaggery improved the antioxidant properties of jams (total phenolic content, total flavonoid content, antiradical activity by the DPPH and ABTS methods), proportionally to the amount of cane sugar incorporated and more significantly in the case of kiwifruit. Other physicochemical properties were not significantly affected by jaggery, except for color. However, these differences were not crucial in the acceptability tests, since acceptance of jams containing jaggery was generally good, very good when intermediate replacement percentages were used. Conclusions of the present work suggest that granulated jaggery can be used to formulate sugar-rich food products such as jams in order to increase their nutritional value, with little impact on physicochemical properties and good consumer acceptance.

Evaluation of Amazon fruits: chemical and nutritional studies on Borojoa sorbilis

BACKGROUND

Borojoa sorbilis (Ducke) is an Amazonian species with edible fruits that are widely consumed by the local population, but little studied and not yet economically explored. Thus the aim of this study was to describe the chemical composition, volatile compounds, nutritional aspects and antioxidant activity of the fruit pulp and peel of B. sorbilis.

RESULTS

Headspace solid-phase microextraction, using polydimethylsiloxane-divinylbenzene (PDMS-DVB) fiber, resulted in the identification of 59 substances in the pulp and peel of B. sorbilis fruits after analysis of the chromatograms obtained by gas chromatography-mass spectrometry using polar and nonpolar columns. Esters were the most abundant. Moisture, lipids, protein, dietary fiber, ash, carbohydrate, total energy value, titratable acid, soluble solids and pH were measured. Protein amount, fat content and antioxidant activity were low in both pulp and peel. Carbohydrate content was 179.2 and 134.9 g kg^-1 in pulp and peel, respectively.

CONCLUSION

This is the first report on the chemical characteristics, flavor and nutritional aspects of B. sorbilis fruit, which is essential to its economic exploitation. The high energy value associated with the carbohydrate content, plus the low fat content, contribute to a possible use of B. sorbilis fruits as a food supplement. © 2018 Society of Chemical Industry.

Influence of Low Glycaemic Index Sweeteners on Antioxidant, Sensory, Mechanical, and Physicochemical Properties of a Watermelon Jelly

The replacement of sucrose by new noncariogenic and low glycaemic index sweeteners (isomaltulose and tagatose) and the addition of natural watermelon juice in jelly have been assessed in terms of composition, texture, colour, antioxidant activity, microbiology, and sensory properties. These analyses were performed initially and after 15 days of storage. Furthermore, the values were compared with those obtained in the analyses of a commercial watermelon jelly. The results showed that the antioxidant activity increased with the storage time in the control sample and in samples combining isomaltulose and tagatose. In addition, noncariogenic and low glycaemic index sweeteners did not affect the instrumental texture. However, the colour changed, especially in the sample containing tagatose only. Finally, the dessert containing tagatose and isomaltulose in equal proportion achieved a similar score in the sensory evaluation as the commercial one, showing the feasibility of using these sweeteners to reformulate watermelon jelly.