UV-C Light: A Promising Preservation Technology for Vegetable-Based Nonsolid Food Products.

A variety of bioactive substances present in fruit- and vegetable-processed products have health-promoting properties. The consumption of nutrient-rich plant-based products is essential to address undernutrition and micronutrient deficiencies. Preservation is paramount in manufacturing plant-based nonsolid foods such as juices, purees, and sauces. Thermal processing has been widely used to preserve fruit- and vegetable-based products by reducing enzymatic and microbial activities, thereby ensuring safety and prolonged shelf life. However, the nutritional value of products is compromised due to the deleterious effects of thermal treatments on essential nutrients and bioactive compounds. To prevent the loss of nutrients associated with thermal treatment, alternative technologies are being researched extensively. In studies conducted on nonsolid food, UV-C treatment has been proven to preserve quality and minimize nutrient degradation. This review compiles information on the use of UV-C technology in preserving the nutritional attributes of nonsolid foods derived from fruit and vegetables. The legislation, market potential, consumer acceptance, and limitations of UV-C are reviewed.

Valorisation of Wasted Immature Tomato to Innovative Fermented Functional Foods.

In this study, the lactic fermentation of immature tomatoes as a tool for food ingredient production was evaluated as a circular economy-oriented alternative for valorising industrial tomatoes that are unsuitable for processing and which have wasted away in large quantities in the field. Two lactic acid bacteria (LAB) were assessed as starter cultures in an immature tomato pulp fermentation to produce functional food ingredients with probiotic potential. The first trial evaluated the probiotic character of Lactiplantibacillus plantarum (LAB97, isolated from immature tomato microbiota) and Weissella paramesenteroides (C1090, from the INIAV collection) through in vitro gastrointestinal digestion simulation. The results showed that LAB97 and C1090 met the probiotic potential viability criterion by maintaining 6 log10 CFU/mL counts after in vitro simulation. The second trial assessed the LAB starters' fermentative ability. Partially decontaminated (110 °C/2 min) immature tomato pulp was used to prepare the individually inoculated samples (Id: LAB97 and C1090). Non-inoculated samples, both with and without thermal treatment (Id: CTR-TT and CTR-NTT, respectively), were prepared as the controls. Fermentation was undertaken (25 °C, 100 rpm) for 14 days. Throughout storage (0, 24, 48, 72 h, 7, and 14 days), all the samples were tested for LAB and Y&M counts, titratable acidity (TA), solid soluble content (SSC), total phenolic content (TPC), antioxidant capacity (AOx), as well as for organic acids and phenolic profiles, and CIELab colour and sensory evaluation (14th day). The LAB growth reached ca. 9 log10 CFU/mL for all samples after 72 h. The LAB97 samples had an earlier and higher acidification rate than the remaining ones, and they were highly correlated to lactic acid increments. The inoculated samples showed a faster and higher decrease rate in their SSC levels when compared to the controls. A nearly two-fold increase (p < 0.05) during the fermentation, over time, was observed in all samples' AOx and TPC (p < 0.05, r = 0.93; similar pattern). The LAB97 samples obtained the best sensory acceptance for flavour and overall appreciation scores when compared to the others. In conclusion, the L. plantarum LAB97 starter culture was selected as a novel probiotic candidate to obtain a potential probiotic ingredient from immature tomato fruits.

Particle Size Effect of Integral Carob Flour on Bioaccessibility of Bioactive Compounds during Simulated Gastrointestinal Digestion.

Carob fruit is native to the Mediterranean region and produced mainly in Portugal, Italy, Morocco and Turkey. The production of the carob fruit in Portugal is highly extensive and sustainable. Currently, carob flour (CF) production is mainly achieved after pulp separation, despite it having been demonstrated that the seeds improve the extraction efficiency of bioactive compounds such as polyphenols, promoting human health. This study aimed to produce an integral CF through an innovative process and assess its physicochemical and bioactive properties at different particle sizes throughout simulated gastrointestinal tract (GIT) digestion. The sugar content profile obtained throughout GIT digestion indicated that sucrose, the sugar present at the highest concentration in undigested CF, was digested and broken down into simple sugars, namely glucose and fructose. The total phenolic content (TPC) and antioxidant activity obtained for the ≤100 µm fraction were in accordance and gastric digestion promoted an increase in the TPC value compared to the undigested sample. The >100 µm fractions displayed a distinct profile from the ≤100 µm fraction. This study showed that the particle size affects the sugar, antioxidant and total phenolic content of CFs and also their gastrointestinal tract digestion. The ≤100 µm fraction demonstrated the most suitable profile as a functional food ingredient.

Food Composition Databases: Does It Matter to Human Health?

Food provides humans with more than just energy and nutrients, addressing both vital needs and pleasure. Food habits are determined by a wide range of factors, from sensorial stimuli to beliefs and, once commanded by local and seasonal availability, are nowadays driven by marketing campaigns promoting unhealthy and non-sustainable foodstuffs. Top-down and bottom-up changes are transforming food systems, driven by policies on SDGs and by consumer's concerns about environmental and health impacts. Food quality, in terms of taste, safety, and nutritional value, is determined by its composition, described in food composition databases (FDBs). FDBs are then useful resources to agronomists, food and mechanical engineers, nutritionists, marketers, and others in their efforts to address at maximum human nutrient needs. In this work, we analyse some relevant food composition databases (viz., purpose, type of data, ease of access, regularity of updates), inspecting information on the health and environmental nexus, such as food origin, production mode as well as nutritional quality. The usefulness and limitations of food databases are discussed regarding what concerns sustainable diets, the food 'matrix effect', missing compounds, safe processing, and in guiding innovation in foods, as well as in shaping consumers' perceptions and food choices.

Combined pre-treatments effects on zucchini (Cucurbita pepo L.) squash microbial load reduction.

Freezing vegetables requires pre-treatments to reduce microbial load and destroy enzymes that impair the frozen product quality. So far blanching has been the most effective pre-treatment, preferred by the food industry, despite its severity: heating up to temperatures close to 100 °C for 1-3 min causes sensory and texture changes in most horticultural products. Alternative blanching treatments, using UV-C radiation combined with milder thermal treatments or with thermosonication, may improve the quality of the final frozen vegetables. Zucchini (Cucurbita pepo L.), the vegetable under study, has an availability in fresh restricted to a season, needing therefore to be often frozen to be used throughout the year. In this study, its surface was first inoculated with two vegetable contaminants, Enterococcus faecalis and Deinococcus radiodurans cells, which are resistant, respectively, to high temperatures and to radiation and then submitted to several blanching treatments, single or combined, and the effect on these microorganisms reduction was evaluated. As single treatments, water blanching (the control treatment, as it is the blanching treatment traditionally used) was applied up to 180 s at temperatures ranging from 65 to 90 °C, and UV-irradiation applied in continuous. As combined pre-treatments, water blanching combined with UV-C (continuous or in pulses), and thermosonication (20 kHz at 50% of power) combined with UV-C pulses were also studied. The continuous UV-C radiation incident irradiance was 11 W/m2 up to 180 s, and the pulses at incident radiance of 67 W/m2, lasting 3.5 s each (35 pulses). Mathematical modeling of bacterial reduction data was carried out using the Bigelow, the Weibull and Weibull modified models, and estimation of their respective kinetic parameters proved that the latter models presented a better fit below 75 °C. The best results proved to be the combination of water blanching at temperatures as low as 85 °C during <2 min with 25 pulses of UV-C (incident irradiance of 67 W/m2) or thermosonication at 90 °C also combined with UV-C pulses, both resulting in 3 log reductions of both microorganisms under study. These results proved to overcome what industry is requiring so far (a 2 log microbial reduction in 3 min), hence minimizing quality changes of frozen zucchini.

Mathematical modeling of gallic acid release from chitosan films with grape seed extract and carvacrol.

Controlled release of antimicrobial and antioxidant compounds from packaging films is of utmost importance for extending the shelf-life of perishable foods. This study focused on the mathematical modeling of gallic acid release into an aqueous medium from three chitosan films, formulated with grape seed extract (GSE) and carvacrol. We quantified the release by HPLC technique during 30days at three temperatures (5, 25 and 45°C). The diffusion coefficients, varying with temperature according to an Arrhenius-type relationship, and the respective activation energies for Film-1 and Film-2 were, respectively [Formula: see text] m2s-1 and [Formula: see text] m2s-1, Ea1=58kJmol-1 and Ea2=60kJmol-1 as obtained from the Fickian fit. The low concentrations of gallic acid released by Film-3 could not be detected by HPLC, therefore the respective diffusion coefficient was not estimated. This study will help with the development and optimization of active packaging (AP) films aiming at improved food preservation and shelf-life extension.

Alicyclobacillus acidoterrestris spores as a target for Cupuaçu (Theobroma grandiflorum) nectar thermal processing: kinetic parameters and experimental methods.

The kinetic parameters of thermal inactivation of a spore former, Alicyclobacillus acidoterrestris, in a tropical fruit nectar [25% of Cupuaçu (Theobroma grandiflorum) pulp and 15% sugar] were determined by the isothermal method (IM), under batch heating, and by the paired equivalent isothermal exposures (PEIE) method, under non-isothermal continuous conditions. The isothermal experiments were repeated three times, every 4 months, with the same spore suspension kept frozen between experiments. The aging of spores, under frozen storage, seemed to produce a notorious increase in the z-value from experiment to experiment: Experiment 1 (z = 7.8 +/- 2.6 degrees C, D(95 degrees C) = 5.29 +/- 0.96 min), Experiment 2 (z = 22 +/- 5 degrees C, D(95 degrees C) = 5.99 +/- 0.63 min), and Experiment 3 (z =29 +/- 10 degrees C, D(95 degrees C) = 3.82 +/- 0.48 min). The evaluation of the kinetic parameters by the PEIE method was carried out in parallel with Experiment 3, with the same aged spores, and the results (z = 31 +/- 6 degrees C, D(95 degrees C) = 5.5 +/- 1.2 min) were close to the ones obtained in this experiment. From this work, it seems that the PEIE method can also be applied to evaluate the reduction parameters of a spore-forming microorganism, and in a more realistic way, since the continuous system eliminates the errors caused by come-up and cool-down times (CUT and CDT) that are unavoidable in isothermal experiments. Therefore, when designing a thermal process for a continuous system, the PEIE method should be used, or the chances are that the process would be underdesigned, risking that the desired level of spore inactivation would not be achieved. An optimization of the thermal processing conditions was next performed for Cupuaçu nectar, considering a 5D reduction in A. acidoterrestris spores. If a pasteurization process is considered, the conditions that ensure safety (9 min at 98 degrees C) only allow a 55% retention of ascorbic acid (AA). If sterilization is considered, 8 s at 115 degrees C will ensure a safe product and retain 98.5% of the original ascorbic acid. Therefore, if A. acidoterrestris is considered as the target microorganism, the nectar should undergo an aseptic high temperature short time principle (HTST) process to achieve a 5D reduction in this acidophilus spore former. However, if the hot-fill-and-hold pasteurization process is preferred, the product should be fortified with ascorbic acid.