Degradation Kinetics of Betacyanins during the Pasteurization and Storage of Cactus Pear (Opuntia dillenii Haw.) Juice Using the Arrhenius, Eyring, and Ball Models

Exploring the potential of red pitaya pulp (Hylocererus sp.) as a plant-based matrix for probiotic delivery and effects on betacyanin content and flavoromics

This study evaluated the potential of red pitaya pulp fermented with Lacticaseibacillus paracasei subsp. paracasei F-19 (F-19) as a base for probiotic products. Physicochemical parameters, sugar, betacyanin, and phenolic contents, and antioxidant activity were analyzed over 28 days at 4 °C and compared to a non-fermented pulp, and to a pulp fermented with Bifidobacterium animalis subsp. lactis BB-12 (BB-12). Volatile compounds were identified using HS-SPME/GC-MS. Probiotic viability during storage and survival through in vitro-simulated gastrointestinal tract (GIT) stress were assessed. Red pitaya pulp, rich in moisture (85.83 g/100 g), carbohydrates (11.65 g/100 g), and fibers (2.49 g/100 g), supported fermentation by both strains. F-19 and BB-12 lowered pH, with F-19 showing stronger acidification, and maintained high viability (8.85-8.90 log CFU/mL). Fermentation altered sugar profiles and produced unique volatile compounds, enhancing aroma and sensory attributes. F-19 generated 2-phenylethanol, a unique flavor compound, absent in BB-12. Phenolic content initially increased but antioxidant activity decreased during storage. Betacyanin remained stable for up to 14 days. Red pitaya improved F-19 viability through the simulated GIT, while BB-12 populations significantly decreased (p < 0.05). These results suggest red pitaya pulp is a promising plant-based matrix for F-19, offering protection during digestion and highlighting its potential as a functional food with enhanced bioactive compound bioavailability and sensory attributes.

Ultrasound-assisted extraction and encapsulation of betalain from prickly pear: Process optimization, in-vitro digestive stability, and development of functional gummies

The study aimed to extract and encapsulate betalain pigment from prickly pear (Opuntia ficus-indica) using ultrasound-assisted extraction and eco-friendly glycerol. Subsequent analysis encompassed assessing its thermal stability, shelf-life, bio-accessibility, and biological properties. The process optimization employed Response Surface Methodology (RSM), focusing on glycerol concentration (20-50 %), sample to solvent ratio (1:10-1:20), temperature (30-60 °C), and time (10-30 min). Optimal conditions were determined as 23.15 % glycerol, 1:10 sample to solvent ratio, 10.43 min treatment time, and 31.15 °C temperature. Under these conditions, betalain content reached 858.28 mg/L with a 93.76 % encapsulation efficiency. Thermal stability tests (80-180 °C; 30 & 60 min) showed degradation of betalain with higher temperatures and longer durations, affecting the visual aspect (ΔE) of the pigment. Encapsulated betalain exhibited favorable shelf stability, with optimal storage life of 404.27 days at 4 °C in amber conditions, compared to 271.99 days at 4 °C without amber, 141.92 days at 25 °C without amber, and 134.22 days at 25 °C with amber. Bio-accessibility of encapsulated betalain was significantly higher (2.05 ± 0.03 %) than conventionally extracted pigment (1.03 ± 0.09 %). The encapsulated pigment displayed strong anti-inflammatory properties in dosages of 2-20 µL, with no cytotoxic effects. Additionally, incorporation into gummies was successful and visually approved by sensory panellists. Glycerol proved to be a green encapsulating agent for betalain, offering high shelf life and bio-accessibility, making it suitable for food industry applications. The encapsulated pigment demonstrated robust thermal stability and shelf life, making it suitable for food industry applications. This study highlights glycerol's potential as a sustainable alternative for natural pigment extraction.

Chemical characterization of yellow-orange and purple varieties of Opuntia ficus-indica fruits and thermal stability of their betalains

Betalains are plant pigments with biological properties and can be used instead of synthetic colorants to confer color and functional properties to foods. The objective of this work was to carry out the chemical characterization of two varieties of prickly pear of Opuntia ficus-indica, one of yellow-orange coloration (Mandarina) and the other of purple coloration (Vigor), through measurements of chemical parameters and color in pulp, antioxidant activity, total phenolic compounds, and betalain content. Considering the thermolability of betalains and their potential applications in food, the thermal stability and activation energy of betacyanins from Vigor variety and betaxanthins from the Mandarina variety were also evaluated and compared with those from beetroot, the main source of betalains. Results for chemical characterization agreed with previous prickly pear reports of other regions, while the thermal degradation kinetics of betalains showed a first-order degradation pattern with respect to time and temperature treatment. Betacyanins from Vigor prickly pear showed similar thermal stability to those from beetroot, which was reflected in similar values of activation energy, while betaxanthins from Mandarina prickly pear showed a higher stability, and therefore a higher activation energy, than those from beetroot. Based on the results, the prickly pear varieties used in this study can be considered as a good source of betalains with potential applications in food and, in addition, the methodology for the evaluation of thermostability can be used to compare the stability of betalains from different sources in a temperature range of 50-90°C. PRACTICAL APPLICATION: The varieties of prickly pear used in this study can be considered a good source of red-purple and yellow-orange easily extractable pigments. In addition, we report a methodology that can be used for the evaluation of the thermal stability of these pigments and to compare this stability between different plant sources. Gaining knowledge on betalain thermal stability will make it possible to propose specific applications, for example, in processed foods requiring different pigment stabilities.

Fruit Juices: Technology, Chemistry, and Nutrition 2.0

In recent years, the food industry has increased its interest in the development of functional foods, including fruit juices, due to the increased demand among consumers for foods and beverages that benefit and improve our health [...]

Evolution of antioxidant properties of orange beverage during storage: Effects of time and temperature

Fruit beverages are the most consumed refreshing products worldwide. The quality of these drinks is not only influenced by the initial composition of the product but also by conditions and duration of storage. The purpose of the present investigation was to evaluate the incidence of two conservation parameters (temperature and time) on some bioactive compounds (phenolic, flavonoid, and carotenoid contents) and antioxidant capacity, measured by free radical scavenging activity (RSA) and ferric reducing power (FRP), on orange beverage during storage. The industrial drinking product freshly procured were subjected to storage under variable temperatures (5, 25, 35, and 45 °C) then analyses of bioactive compounds contents and antioxidant activity were performed periodically (0, 10, 20, and 30 days). The results showed that the initial orange beverage was endowed with interesting phenolic compound contents and considerable antioxidant potential. In the exception of 5 °C, which provided steady antioxidant parameters, all other temperatures induced decreases of analyzed phytochemicals and antioxidant activities proportionally with raising of storage temperature. The duration of storage for the temperatures 25, 35, and 45 °C also affected negatively antioxidant parameters in a proportional manner to time. The orange beverage was an interesting natural source of bioactive compounds but the duration of storage in relation to temperature must be chosen properly.

Betalain Extracts from Beetroot as Food Colorants: Effect of Temperature and UV-Light on Storability

Beetroot is a good source of natural food colorants given that it contains significant amount of betalain pigments. This study investigates the three-months storage stability of betalain extracts recovered from unsold beetroot by a specific enzymatic mix. The extract storability was evaluated by the kinetic degradation model of betacyanins and betaxanthins, as well as by pigment color attributes (CIELa*b* parameters) under dark and UV-light exposure at different temperatures (4, 25 and 40 °C). Considering all the tested storage conditions, betaxanthins appeared to be more stable than betacyanins in terms of degradation rate constant, half-life time and activation energy. The effect of UV-light was negligible if the pigment was not exposed to temperatures higher than the room one, since no relevant differences were found between the parameters studied at 4 and 25 °C. Taking into account the visual color, all the investigated color indexes (total color difference, chroma and hue) were mainly affected by temperature, even if mildly high (40 °C), and to a lesser extent by UV-light exposure.

Effect of nonthermal treatments on selected natural food pigments and color changes in plant material

In recent years, traditional high-temperature food processing is continuously being replaced by nonthermal processes. Nonthermal processes have a positive effect on food quality, including color and maintaining natural food pigments. Thus, this article describes the influence of nonthermal, new, and traditional treatments on natural food pigments and color changes in plant materials. Characteristics of natural pigments, such as anthocyanins, betalains, carotenoids, chlorophylls, and so forth available in the plant tissue, are shortly presented. Also, the characteristics and mechanism of nonthermal processes such as pulsed electric field, ultrasound, high hydrostatic pressure, pulsed light, cold plasma, supercritical fluid extraction, and lactic acid fermentation are described. Furthermore, the disadvantages of these processes are mentioned. Each treatment is evaluated in terms of its effects on all types of natural food pigments, and the possible applications are discussed. Analysis of the latest literature showed that the use of nonthermal technologies resulted in better preservation of pigments contained in the plant tissue and improved yield of extraction. However, it is important to select the appropriate processing parameters and to optimize this process in relation to a specific type of raw material.

The Influence of Different Pretreatment Methods on Color and Pigment Change in Beetroot Products

Vegetable processing pomace contains valuable substances such as natural colors that can be reused as functional ingredients. Due to a large amount of water, they are an unstable material. The aim of our research was to assess how the pretreatment method (thermal or nonthermal) affects the properties of powders obtained from beet juice and pomace after the freeze-drying process. The raw material was steamed or sonicated for 10 or 15 min, and then squeezed into juice and pomace. Both squeezed products were freeze-dried. The content of dry substance; L*, a*, and b* color parameters; and the content of betalain pigments were analyzed. Pretreatments increased the proportion of red and yellow in the juices. Steam and ultrasound caused a significant reduction in parameter b* in the dried pomace. A significant increase in betanin in lyophilizates was observed after pretreatment with ultrasound and steam for 15 min. As a result of all experiments, dried juices and pomaces can also be used as a colorant source. However, there is higher potential with pomaces due to their additional internal substances as well as better storage properties. After a few hours, juice was sticky and not ready to use.