Nutritional quality of sous vide cooked carrots and brussels sprouts

Modern and traditional cooking methods affect the antioxidant activity and phenolic compounds content of Trachystemon Orientalis (L.) G. Don

Trachystemon orientalis (L.) G. Don is a medicinal plant with beneficial effects on human health. Its antioxidant and phenolic compound content is higher than most natural plants. This is the first study on the cooking of this consumed plant. This study investigated how different cooking methods and times affect the antioxidant activity and phenolic compound content of Trachystemon orientalis (L.) G. Don. The Folin-Ciocalteu method (FCR), ferric-reducing antioxidant power (FRAP), copper-reducing antioxidant capacity (CUPRAC), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity were used to evaluate the antioxidant activity and total phenolic content (TPC). Phenolic compounds were also determined by high-performance liquid chromatography (HPLC). Microwave cooking, stir-frying and sous vide increased TPC and antioxidant activity (p<0.05). Steaming decreased TPC and antioxidant activity (p<0.05). It was determined that the best cooking method and time was stir-frying for 15 minutes (TPC, CUPRAC and FRAP values 45.18±3.91 mg GAE/g DW, 15559.39±106.90 mmol Troloks/g DW and 555.10±24.05 μmol Fe (II)/g DW, respectively). Raw Trachystemon orientalis (L.) G. Don was detected with caffeic acid (31.53±0.25 mg/100 g DW). New phenolic compounds (protocatechuic acid and p-coumaric acid) were formed by boiling, stir-frying, microwaving, and sous vide methods. In conclusion, regarding antioxidant activity and phenolic compounds of Trachystemon orientalis (L.) G. Don; the best cooking methods are microwave, stir-frying, and sous vide (p<0.05). The most wrong cooking method is steaming (p<0.05).

Process optimization and evaluation of the effects of different time-temperature sous vide cooking on physicochemical, textural, and sensory characteristics of whiteleg shrimp (Litopenaeusvannamei)

The objective of the current study was to optimize the cook-chill conditions of high-value whiteleg shrimp (Litopenaeus vannamei) processed using the sous vide (SV) technique and to assess the effects of various time-temperature combinations on the physicochemical, textural, and sensory qualities. For optimization, a Response Surface Methodology (RSM) approach utilizing a Central Composite Design (CCD) was adopted. Optimum SV cooking conditions to acquire minimum texture (hardness) of 7235 g was 13.48 min and 81.87 °C, expressible moisture of 18.48% was 14.5 min and 84.5 °C, and cook loss of 5.58% was 5 min and 75 °C. Texture (hardness) and expressible moisture decreased while cooking loss increased with increasing time-temperature treatment. Redness and yellowness values increased (p < 0.05) with increasing SV cooking time-temperature, but lightness values were nearly consistent in all treatments. With increasing time and temperature, TBARs and total carotenoid content increased (p < 0.05). However, the TBARs values were within accepted limits and ranged from 0.05 to 0.08 mg malonaldehyde/kg. Sensory evaluation indicated that all SV cooked samples were well accepted, with overall scores ≥7. These results suggest that the SV cooking temperature and time had a substantial impact on the textural, physicochemical, and sensory characteristics of shrimp. In addition, increasing time-temperature increased cooking and moisture loss, but decreased hardness and higher sensory scores made the product more acceptable to consumers.

Effects of different processing methods on the polyphenolic compounds profile and the antioxidant and anti-glycaemic properties of horseradish roots (Armoracia rusticana)

Horseradish (Armoracia rusticana) provides human organisms with various effective treatments for improving human health, and it constitutes a salubrious root used for culinary purposes. This outcome derives from the chemical composition and polyphenols content of horseradish. This study's objective was to determine individual polyphenols, total phenolic (TPC) and total flavonoid (TFC) contents, colour parameters, inhibition of advanced glycation end product (AGEs) formation and Trolox Equivalent Antioxidant Capacity (TEAC) by DPPH and ABTS of horseradish products. Phenolic acids and flavonoids were analysed by HPLC-DAD-MS method. Horseradish products were obtained by thermal treatments such as boiling, baking and sous-vide. Fresh and sous-vide samples were characterized by the most abundant TPC values, whereas TFC horseradish indicated the highest value after boiling treatment. Moreover, the highest values of antioxidant capacity in fresh horseradish roots were detected. Flavonoids presented lower concentrations than phenolic acids, while syringic acid was the most abundant phenolic compound. Horseradish, after sous-vide treatment, appeared to have a higher inhibition of AGEs formation. Thermal treatment of horseradish root increased the saturation of yellow (b*) and red (a*) colours and decreased colour brightness. Our findings indicate that horseradish products are a valuable source of polyphenols, with their profile, content, and antioxidant and anti-AGEs formation activity modulated by applied processes.

Sous vide processing: a viable approach for the assurance of microbial food safety

As consumer needs change, innovative food processing techniques are being developed that have minimal impact on food quality and ensure its microbiological safety. Sous vide (SV) is an emerging technology of cooking foods in vacuum pouches at specific temperatures, which results in even heat distribution. Presented here is an overview of the current state of the art in the application of SV techniques for processing and preserving foods. Unlike the conventional thermal food processing approach, the precise nature of the SV method improves food quality, nutrition and shelf-life while destroying microorganisms. Foods processed by SV are usually subjected to temperatures between 50 and 100 °C. Although sufficient for food preparation/processing, its effectiveness in eliminating microbial pathogens, including viruses, parasites, vegetative and spore forms of bacteria, is limited. However, the inactivation of spore-forming microbes can be enhanced by combining the technique with other non-thermal methods that exert negligible impact on the nutritional, flavour and sensory characteristics of foods. In addition to exploring the mechanism of action of SV technology, the challenges related to its implementation in the food industry are also discussed. SV method potential, applications, and impacts on spore-forming microbes and spore inactivation are explored in this review. Through the debate and discussion presented, further research and industrial applications of this food processing method could be guided. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

AT-HOOK MOTIF NUCLEAR LOCALIZED (AHL) proteins of ancient origin radiate new functions

AHL (AT-HOOK MOTIF NUCLEAR LOCALIZED) protein is an important transcription factor in plants that regulates a wide range of biological process. It is considered to have evolved from an independent PPC domain in prokaryotes to a complete protein in modern plants. AT-hook motif and PPC conserved domains are the main functional domains of AHL. Since the discovery of AHL, their evolution and function have been continuously studied. The AHL gene family has been identified in multiple species and the functions of several members of the gene family have been studied. Here, we summarize the evolution and structural characteristics of AHL genes, and emphasize their biological functions. This review will provide a basis for further functional study and crop breeding.

Hydrothermal Treatment Effect on Antioxidant Activity and Polyphenols Concentration and Profile of Brussels sprouts (Brassica oleracea var. gemmifera) in an In Vitro Simulated Gastrointestinal Digestion Model

Brussels sprouts are a source of polyphenolic compounds. However, their concentration is affected by many factors depending on the plant material, hydrothermal treatment methods and digestion in the gastrointestinal tract. The aim of this study was to determine the effect of hydrothermal treatment on the antioxidant activity, concentration and profile of polyphenols of Brassica oleracea var. gemmifera in an in vitro simulated gastrointestinal digestion model. The study showed a significant effect of the type of hydrothermal treatment on total polyphenol concentration, polyphenolic acid profile, flavonoid content and antioxidant activity. Traditional boiling in water was the least effective type of hydrothermal treatment with respect to bioactive components of Brussels sprouts. Sous-vide was the most effective hydrothermal treatment in terms of retention of polyphenolic compounds and high antioxidant activity, thus providing a better alternative to steam cooking. Using an in vitro model, a significant difference was demonstrated between the concentration of bioavailable polyphenolic compounds and the polyphenol content of the plant material before digestion. The influence of the type of hydrothermal treatment used on the concentration of bioavailable polyphenolic compounds was maintained in relation to material not subjected to in vitro digestion (except for antioxidant activity).

Sprout Caffeoylquinic Acid Profiles as Affected by Variety, Cooking, and Storage

Various health-promoting properties inherent to plant-based foods have been attributed to their rich bioactive compounds, including caffeoylquinic acids (CQAs). The potential health benefits of CQAs have been well-documented. While sprouts are widely recognized as health-promoting foods owing to their high phytonutrient content, our knowledge regarding the effect of cooking and storage, commonly practiced by consumers, on the CQA content remains limited. First, sunflower sprouts were found to have the highest total CQA content (~ 22 mg/g dry weight) out of 11 commonly available sprouts. Then, the effect of variety, cooking, and low-temperature storage on the CQA profile of sunflower sprouts was investigated. Among the four different varieties of sunflower sprouts, variety 1 harbored the highest total CQA content. Notably, cooking adversely affected the CQA content of sunflower sprouts relative to the uncooked samples in a time-dependent manner, possibly due to the heat sensitivity of CQAs. Under simulated home-refrigeration storage conditions, we observed a significant decline in the content of major CQA compounds (5-monoCQA and 3,5-diCQA) at days 10 and 13 of storage. The results obtained herein provide consumers and food industrialists with increased insight into the effect of cooking and refrigeration on the CQA content of sunflower sprouts.

Impact of Mild Oven Cooking Treatments on Carotenoids and Tocopherols of Cheddar and Depurple Cauliflower (Brassica oleracea L. var. botrytis)

The effect of steam and sous-vide oven procedures on liposoluble antioxidants of colored cauliflower (orange and purple) was assessed for the first time and compared with domestic practice (boiling). In raw samples, the total carotenoid content was 10-fold higher in Cheddar than in Depurple (20.9 ± 2.1 vs. 2.3 ± 0.5 mg/kg dry weight), whereas the level of tocopherols was similar (28.5 ± 4.4 vs. 33 ± 5.2 mg/kg dry weight). The Cheddar liposoluble antioxidant matter contained violaxanthin, neoxanthin, α-carotene and δ-tocopherol, not detected in Depurple. All tests increased the bioactive compounds extractability with steam oven and sous-vide displaying similar effects, lower than boiling. In boiled Cheddar cauliflower, the total carotenoids and tocopherols contents increased with cooking time until they were 13-fold and 6-fold more than in raw cauliflower, respectively. Conversely, in the Depurple variety, contents increased by half with respect to the orange variety. However, from a nutritional point of view, no differences were revealed among the three different cooking treatments in terms of vitamin A and E levels expressed in μg/100 g of fresh vegetable because of the higher water content of boiled samples that must be considered when evaluating the effect of thermal treatment on cauliflower nutritional traits.

Sous-Vide as a Technique for Preparing Healthy and High-Quality Vegetable and Seafood Products

Sous-vide is a technique of cooking foods in vacuum bags under strictly controlled temperature, offering improved taste, texture and nutritional values along with extended shelf life as compared to the traditional cooking methods. In addition to other constituents, vegetables and seafood represent important sources of phytochemicals. Thus, by applying sous-vide technology, preservation of such foods can be prolonged with almost full retention of native quality. In this way, sous-vide processing meets customers' growing demand for the production of safer and healthier foods. Considering the industrial points of view, sous-vide technology has proven to be an adequate substitute for traditional cooking methods. Therefore, its application in various aspects of food production has been increasingly researched. Although sous-vide cooking of meats and vegetables is well explored, the challenges remain with seafoods due to the large differences in structure and quality of marine organisms. Cephalopods (e.g., squid, octopus, etc.) are of particular interest, as the changes of their muscular physical structure during processing have to be carefully considered. Based on all the above, this study summarizes the literature review on the recent sous-vide application on vegetable and seafood products in view of production of high-quality and safe foodstuffs.

Sous-Vide Nonenzymatic Browning of Glucosamine at Different Temperatures

Sous-vide is an increasingly popular method of cooking under controlled conditions of temperature and time inside vacuumed pouches to preserve the nutritional and sensory qualities of food. Sous-vide nonenzymatic browning of glucosamine (GlcN) was investigated at 50, 60, and 70 °C for 12 h. Changes investigated were pH, color, level of browning, and the concentrations of the key Maillard and caramelization reaction products, including α-dicarbonyls and pyrazines. The concentrations of undesired 4-methylimidazole (4-MEI), 2-acetyl-4(5)-tetrahydroxybutyl imidazole (THI), and 5-hydroxymethylfurfural (5-HMF) were also determined. Six types of caramels were produced of unique composition with no detectable levels of 4-MEI. GlcN caramels produced under vacuum were more acidic and lighter in color, containing significantly less flavorful diacetyl, but more fructosazine (FR) as compared to nonvacuum caramels. THI concentration was well below the toxicity levels for all studied caramels. Principal component analyses showed that the incubation temperature played a key role in determining the composition of caramels.

Comparison of antioxidative properties of raw vegetables and thermally processed ones using the conventional and sous-vide methods

The study determines the antioxidant properties of methanol vegetable extracts from raw vegetables, conventionally cooked vegetables and sous-vide. In the research, two methods were used: free radical scavenging DPPH (µM Trolox) and the reduction of Fe³⁺to Fe²⁺ - FRAP (µM Fe²⁺). Antioxidative properties for raw vegetables were obtained with the range of 7.47-235 (µM Trolox/100g of vegetables) and 2.66-103 (µM Fe²⁺/100g of vegetables), for vegetables after the conventional cooking process 6.15-657 (µM Trolox/100g of vegetables) and 3.03-99.9 (µM Fe²⁺/100g of vegetables), for vegetables after the sous-vide process 4.45-648 (µM Trolox/100g of vegetables) and 3.06-99.9 (µM Fe²⁺/100g of vegetables). For some vegetables, an increase in the antioxidative potential was observed as a result of cooking processes; however, it was much higher for the sous-vide technique. All results were subjected to a one-way analysis of variance (ANOVA) and, if significant differences were revealed, the POST-HOC Duncan test was used (α=0.05).

Influence of cooking conditions on organoleptic and health-related properties of artichokes, green beans, broccoli and carrots

Colour, pigments, total phenolic content and antioxidant activity were investigated in artichokes, green beans, broccoli and carrots cooked under different conditions. Domestic induction hobs with temperature control were used to evaluate the effect of boiling, sous-vide cooking and water immersion cooking at temperatures below 100°C on the properties of each vegetable. Sous-vide cooking preserved chlorophyll, carotenoids, phenolic content and antioxidant activity to a greater extent than boiling for all of the vegetables tested and retained colour better, as determined by a(∗). A reduction of only 10-15°C in the cooking temperature was enough to improve the properties of the samples cooked by water immersion, except for green beans. Artichokes and carrots suffered pronounced losses of antioxidant activity during boiling (17.0 and 9.2% retention, respectively), but the stability of this parameter significantly increased with sous-vide cooking (84.9 and 55.3% retention, respectively).

The effects of sous-vide cooking parameters on texture and cell wall modifications in two apple cultivars: A response surface methodology approach

This work aimed at evaluating the effects of sous-vide cooking parameters, such as time and temperature and their interactions, on textural attributes of 'Mondial Gala' and 'Granny Smith' apple cultivars. For this, different response surface methodology-based models were developed. This methodology proved a suitable means for the assessment of changes in textural parameters and cell wall modifications during the processing of apples. 'Mondial Gala' fruit displayed better aptitude for the preservation of textural properties after high-temperature processing conditions and were therefore apparently more suited to sous-vide cooking than 'Granny Smith' apples. Pectin methylesterase activity levels in 'Mondial Gala' apples were enhanced at mild temperatures and pectins in this cultivar displayed a lower degree of methylation. Therefore, the establishment of calcium-mediated linkages between cell wall polymers might have been favoured in 'Mondial Gala' apples, thus reinforcing tissues and improving the preservation of textural attributes, in comparison to 'Granny Smith' samples.

Potential Properties of Plant Sprout Extracts on Amyloid β

The aim of this study is to examine the amyloid β (Aβ) inhibition mechanism of plant sprouts' aqueous extracts (PSAE). In this study, we screened the effects of five plant sprouts' extracts on Aβ (1–42) structure modification using gel electrophoresis. In PSAE, no band of Aβ monomer was recognized in Japanese butterbur. Similarly, the Aβ monomer band became light in buckwheat, red cabbage, broccoli, and brussels. The neuroprotective effects of PSAE were evaluated by measuring levels of Aβ in mixtures (Aβ  and PSAE) with Aβ ELISA assay. The treatment with PSAE decreased Aβ levels. The results indicated that the levels of red cabbage, Japanese butterbur, and broccoli were 9.6, 28.0, and 44.0%, respectively. The lowest value was observed with buckwheat. Furthermore, we carried out a Congo Red (CR) and Aβ binding experiment of PSAE to confirm the modification mechanism of PSAE. The correlation coefficient for the absorption spectrum peak of CR was found to be bigger than 0.8 (r = 0.882) which proved that the Aβ levels could be attributed to the peak of CR. In conclusion, we demonstrated that treatment with PSAE effectively decreases Aβ concentration. Thus, the mechanism that decreased the Aβ levels may be modification by PSAE.

Determination of several families of phytochemicals in different pre-cooked convenience vegetables: effect of lifetime and cooking

Phytochemicals content, including several families such as phenolic acids, isoflavones, flavones, flavonols, isothiocyanates, and glucosinolates, was determined in pre-cooked convenience vegetables by ultra high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS). It was observed that there is not a common behavior of the individual concentration of phytochemicals during the lifetime and cooking of the matrix, and compounds change their concentration without a specific trend. It was observed that neither lifetime nor cooking process have significant effects on the total content of phytochemicals except in broccoli, although some changes in the individual content of the target compounds were observed, suggesting that interconversion processes could be performed during the lifetime and/or cooking process of the product.