Antimicrobial, Antioxidant, Sensory Properties, and Emotions Induced for the Consumers of Nutraceutical Beverages Developed from Technological Functionalised Food Industry By-Products

Egle Zokaityte; Vita Lele; Vytaute Starkute; Paulina Zavistanaviciute; Darius Cernauskas; Dovile Klupsaite; Modestas Ruzauskas; Juste Alisauskaite; Alma Baltrusaitytė; Mantvydas Dapsas; Karolina Siriakovaite; Simonas Trunce; Raquel P F Guiné; Pranas Viskelis; Vesta Steibliene; Elena Bartkiene

doi:10.3390/foods9111620

Antimicrobial, Antioxidant, Sensory Properties, and Emotions Induced for the Consumers of Nutraceutical Beverages Developed from Technological Functionalised Food Industry By-Products

Foods. 2020 Nov 6;9(11):1620. doi: 10.3390/foods9111620.

Authors

Egle Zokaityte^{1

2}, Vita Lele^{1

2}, Vytaute Starkute^{1

2}, Paulina Zavistanaviciute^{1

2}, Darius Cernauskas², Dovile Klupsaite², Modestas Ruzauskas^{3

4}, Juste Alisauskaite¹, Alma Baltrusaitytė¹, Mantvydas Dapsas¹, Karolina Siriakovaite¹, Simonas Trunce¹, Raquel P F Guiné⁵, Pranas Viskelis⁶, Vesta Steibliene⁷, Elena Bartkiene^{1

2}

Affiliations

¹ Department of Food Safety and Quality, Faculty of Veterinary, Lithuanian University of Health Sciences, Tilzes Str. 18, LT-47181 Kaunas, Lithuania.
² Institute of Animal Rearing Technologies, Faculty of Animal Sciences, Lithuanian University of Health Sciences, Tilzes Str. 18, LT-47181 Kaunas, Lithuania.
³ Department of Anatomy and Physiology, Faculty of Veterinary, Lithuanian University of Health Sciences, Tilzes Str. 18, LT-47181 Kaunas, Lithuania.
⁴ Institute of Microbiology and Virology, Faculty of Veterinary, Lithuanian University of Health Sciences, Tilzes Str. 18, LT-47181 Kaunas, Lithuania.
⁵ CERNAS Research Centre, Polytechnic Institute of Viseu, 3504-510 Viseu, Portugal.
⁶ Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, Kauno Str. 30, LT-54333 Babtai, Lithuania.
⁷ Psychiatry Clinic, Faculty of Medicine, Lithuanian University of Health Sciences, A. Mickeviciaus Str. 9, LT44307 Kaunas, Lithuania.

Abstract

This study aims to develop nutraceutical beverages containing food processing by-products in their formulation, and determine the opinion of consumers. This is done by testing whether they know that the main ingredients of the product are by-products, performing an overall acceptability test of the developed beverages, and evaluating the emotions induced by the newly developed beverages for consumers. The main ingredients used for the preparation of added-value beverages were fermented milk permeate (containing galactooligosaccharides), extruded and fermented wheat bran (WB) (containing ≥6.0 log₁₀ CFU g^-1 viable antimicrobial properties showing lactic acid bacteria (LAB) strains), and different fruit/berry by-products (FBB) (as a source of compounds showing antioxidant properties). The definition of the quantities of bioactive ingredients was based on the overall acceptability of the prepared beverages, as well as on emotions induced in consumers by the tested beverages. Functional properties of the developed beverages were proofed by the evaluation of their antimicrobial and antioxidant properties, as well as viable LAB count during storage. Desirable changes in extruded and fermented WB were obtained: Fermentation reduced sugar concentration and pH in samples with predominant lactic acid isomer L(+). In addition, the viable LAB count in the substrate was higher than 6.0 log₁₀ CFU g^-1, and no enterobacteria remained. By comparing the overall acceptability of the beverages enriched with WB, the highest overall acceptability was shown for the samples prepared with 10 g of the extruded and fermented WB (7.9 points). FBB showed desirable antimicrobial activity: Shepherd inhibited-2, sea buckthorn-3, blueberries-5, and raspberries-7 pathogens from the 10 tested. Comparing different beverage groups prepared with different types of FBB, in most cases (except sea buckthorn), by increasing FBB content the beverages overall acceptability was increased, and the highest score (on average, 9.5 points) was obtained for the samples prepared with 5.0 and 7.5 g of blueberries FBB. Moreover, a very strong positive correlation (r = 0.8525) was found between overall acceptability and emotion "happy" induced in consumers by the prepared beverages enriched with extruded and fermented WB and FBB. By comparing the samples prepared with the addition of WB with samples prepared with WB and FBB, it was observed that most FBB increased total phenolic compounds (TPC) content (on average, by 9.0%), except in the case of samples prepared with sea buckthorn. A very high positive correlation (r = 0.9919) was established between TPC and antioxidant activity. Finally, it can be stated that the newly developed nutraceutical beverages were acceptable for consumers, induced positive emotions, and possessed desirable antimicrobial and antioxidant properties, while being prepared in a sustainable and environmentally friendly manner.

Keywords: antimicrobial properties; antioxidant properties; beverages; emotions induced for consumers; fruit/berry by-products; milk permeate; overall acceptability; wheat bran.