Analysis of selected functional properties, resource demands and energy consumption of freeze‐dried vegetable snacks

Development and physicochemical characteristics of multicomponent freeze-dried snacks obtained with blackcurrant pomace powder and calcium ions as structuring agents

Consumers seek healthy and sustainable products, whereas the food industry faces the challenge of processing by-products management. The application of fruit pomace as an additive could be a solution addressing the needs of both consumers and producers. The research objective has been to assess the effect of dried blackcurrant pomace powder (BP) and calcium ions in varied concentration on the physicochemical properties of multicomponent freeze-dried snacks as compared to the influence of low-methoxyl pectin (LMP). The snacks were prepared using varied content of BP (1, 3, 5%) and calcium lactate (0, 0.01, 0.05%). Water content and activity, hygroscopic properties, structure, texture, colour, polyphenols content (TPC), and antioxidant activity were analysed. The addition of BP resulted in lowering water activity and porosity. The microstructure of the snacks consisted of a large number of small and unevenly distributed pores. Consequently, the reduction of hygroscopic properties with the growing amount of BP was observed. Applied additives strengthened the structure and caused changes in compression curves indicating enhanced hardness and crispiness. The effect given by 5% of BP was comparable to that obtained with 0.5% of LMP. Additionally, blackcurrant pomace infusion increased TPC and enhanced antioxidant activity but it also caused significant changes in the colour of the snacks. Overall, obtained results have shown that dried blackcurrant pomace powder (BP) can be successfully applied as a food additive supporting stability, texture, and bioactive compounds content, thus fortifying the physicochemical properties of freeze-dried fruit and vegetable snacks.

The effect of apple pomace powder and calcium ions on selected physicochemical properties of freeze-dried carrot-orange-ginger snacks

BACKGROUND

This study aimed to determine the effect of various amounts of dried apple pomace (AP) powder and calcium ions on selected physicochemical properties of restructured freeze-dried snacks in comparison with products obtained with low-methoxyl pectin (LMP). The material was prepared using frozen carrot, orange concentrate, ginger, water, and various concentrations of AP (1, 3, 5%) and calcium lactate (0, 0.01, 0.05%). The reference samples were without additives, and with 0.5 or 1.5% of LMP combined with 0.01% of calcium lactate.

RESULTS

The material was studied in terms of water content and activity, hygroscopic properties, structure, texture, color, and polyphenol content (TPC), and antioxidant activity. The addition of AP resulted in reducing water activity and porosity. As a consequence of the increasing density of the structure, the reduction of hygroscopic properties by up to 16% followed the increasing amount of AP. Apple pomace and calcium ions strengthened the structure. The addition of 3% and 5% of AP gave a hardening effect close to or better than 0.5% LMP. Because of the pigment dilution, LMP caused significantly greater total color change than AP. The incorporation of AP also increased TPC and enhanced antioxidant activity in comparison with the reference materials by up to 18%.

CONCLUSION

The results showed that dried AP powder can be applied successfully as an additive enhancing stability, texture and bioactive compound content, thus fortifying the physicochemical properties of restructured freeze-dried fruit and vegetable snacks. © 2023 Society of Chemical Industry.