Free Sugar Content Research Articles

Chitosan xerogel embedded with green synthesized cerium oxide nanoparticle: An effective controlled release fertilizer for improved cabbage growth

With the growing awareness on the adverse effects of conventional fertilizers; the use of sustainable and controlled release fertilizers has garnered much significance. In the present study, we report the synthesis of chitosan-benzaldehyde Schiff base xerogel incorporated with green synthesized cerium oxide nanoparticle using Psidium guajava leaves extract as a sustainable fertilizer. Spherical CeO2 NPs having an average particle size of 15.3 nm and zeta potential of – 39.9 mV was obtained. The urea-loaded nanocomposite xerogel (CsB@U/CeO2) was examined for cabbage growth. The water retention capacity extended for >2 weeks. A controlled release profile for urea was accomplished from CsB@U/CeO2 for a period extending for 30 days. The kinetics assay suggested that presence of CeO2 NPs asserted a greater role in urea-controlled release from the CsB@U/CeO2 nanocomposite hydrogel owing to polymer relaxation. The growth parameters of cabbages such as head height, diameter, fresh head weight, head circumference was enhanced in plants fertilized by CsB@U/CeO2 as compared to urea. Furthermore, the phenolic content, free radical scavenging activity, protein content, sugar and flavonoid content were also found higher in CsB@U/CeO2 fertilized plants. This study puts forth CsB@U/CeO2 xerogel can be potentially harnessed as an alternative to urea in sustainable agriculture.

Impact of fermentation by Saccharomyces Cerevisiae on the macronutrient and in vitro digestion characteristics of Chinese noodles

This study examined the impact of live bread yeast (Saccharomyces cerevisiae) on the nutritional characteristics of Asian dried noodles. Micronutrient analysis of fermented noodles revealed a 6.9% increase in the overall amino acid content, a 37.1% increase in the vitamin B content and a 63.0% decrease in the phytic acid level. Molecular weight analysis of starch and protein contents revealed moderate decrease in the fermented noodles. The in vitro digestion of fermented noodles showed a slightly faster initial acidification, four-fold decrease in the initial shear viscosity (from 8.85 to 1.94 Pa·s). The initial large food particle count (>2 mm diameter) was 19.5% lower in the fermented noodles. The fermented noodles contained slightly higher free sugar content (73.5 mg g−1 noodle) during the gastric digestion phase. The overall nutrition and digestion results indicate nutritional improvement and digestion-easing attributes in the fermented noodles.

Comparative analysis of bioenergy and mycoprotein production from apple pomace: Strategies for enhancement and environmental benefits

Apple pomace constitutes a major waste stream of the food processing industry that is characterized by high concentrations of free sugars and structural carbohydrates. This study comparatively explored alternative apple pomace valorization strategies. To this regard, the integration of hydrothermal and organic acid pretreatment as a strategy to enhance anaerobic digestion biomethane yield and alternative production of mycoprotein as a valuable secondary product via the use of Aspergillus oryzae and Neurospora intermedia edible fungi were investigated. In scenario 1, both pretreatment liquors and solid residues underwent anaerobic digestion to produce biomethane. In scenario 2, pretreatment liquors and solid residues underwent fungal cultivation and anaerobic digestion, respectively. Additionally, to optimize bioenergy yield and minimize wastewater generation in scenario 2, the fungal growth effluent was also subjected to anaerobic digestion. In scenario 1, employing methane for transportation showed the potential to decrease GHG by 314.8 kt CO2 eq, translating to US$72.4 million in social cost savings. Similarly, in scenario 2, replacing edible fungal biomass in the food market could lead to a substantial reduction in emissions by 824.2 kt CO2 eq and a corresponding US$227.0 million in social cost savings.

EFFECT OF CRYO-STORAGE ON STORABILITY OF PAPAYA SEEDS

A fruit crop of significant economic importance, papayas are often propagated from seeds. Based on their freezing injury even at low moisture content, papaya seeds are classified as "intermediate seeds"; and rapid loss of viability in storage is assumed to be the primary cause of poor germination; thus, the development of appropriate technology is necessary to prolong the storability of papaya seeds. One such effective technology for prolonged seed storability is cryo-storage. The purpose of the current study was to investigate how cryostorage affects papaya seed storability. For this investigation, TNAU Papaya variety CO 8 seeds were utilised. Five distinct treatments were applied to the seeds, which were then kept for approximately six months at liquid nitrogen's vapour phase (-140°C). The biochemical parameters such as protein content, free amino acid, total carbohydrates, free sugars, total lipids, and dehydrogenase activity were measured on a monthly basis along with seed germination and seedling vigour in the cryopreserved papaya seeds. Results indicated that papaya seeds that had been vitrified (seeds with a 10% moisture content that had been soaked in loading solution for 20 minutes, then immersed in Plant Vitrification Solution 2 (PVS2) for another 20 minutes, packed in cryovials and kept in cryo-storage at -140°C) compared to papaya seeds that were packed in cloth bags and stored in ambient conditions had higher seed germination, dry matter production and vigour index at six months after storage. In comparison to fresh seeds, the results also showed that, after six months of cryo-storage, biochemical proximate, protein content, total carbohydrate content, total lipid content, and dehydrogenase activity were maintained in the aforementioned treatment with minimum reduction, while electrical conductivity, free amino acid content, and free sugar content gradually increased with the storage period at minimum rate. In crux, vitrified papaya seeds packaged in cryovials and kept in cryo-storage at -140°C preserved their quality for six months, meeting Indian Minimum Seed Certification Standards. This could be useful for storing papaya seeds for longer periods of time. Keywords: Papaya, vitrification, differential scanning calorimetry, liquid nitrogen, cryo-storage

Effects of moisture content and packaging on color stability of red pepper (Capsicum annuum L.) powder.

The color stability and quality changes of red pepper powder of various initial moisture content (7%, 10%, and 13%) and packaged with different materials, low-density polyethylene (LDPE) and nylon layered polyethylene (Ny/PE) film pouches or plastic and glass bottles, were compared during storage at 20°C for 126days. In the 7% moisture content sample packaged in LDPE film and plastic bottles, the L* and b*-values increased from 48.2 ± 0.7 and 15.4 ± 1.1 to 65.2-65.9 and 29.5-30.3, respectively, while the a*-value decreased from 26.1 ± 0.7 to 14.2-15.9, indicating a noticeable color change from red to orange. However, the decrease in the capsaicinoid and free sugar content of red pepper powder over time was found to have no significant correlation with moisture content and packaging type. As a result, the color change during the long-term storage of red pepper powder was greatly influenced by the initial moisture content and gas permeability of the packaging material.

Differences in analytical methods affect the analytical values of soluble solids, free sugar, and organic acid content of strawberries

The present study compares different pre-treatments used to analyze free sugars and organic acids in strawberries. Soluble solid content, free sugars, and organic acid content in strawberries may vary depending on the pre-treatment methods used for analyze. A comparison of freshly squeezed juice and that obtained post freezing and thawing revealed a significant reduction in sucrose content in the once-frozen juice. However, no significant differences were observed in the soluble solids, glucose, and fructose contents. Furthermore, crushed flesh had significantly higher soluble solid, glucose, and fructose levels and lower sucrose content than those of the juice. Crushed flesh exhibited significantly higher citric acid and a lower malic acid content than those in the juice. There was a significant reduction in sucrose content in the freeze-dried samples compared to all other pre-treatments. Contrastingly, citric and malic acid levels were higher in the freeze-dried samples than that in the freshly crushed samples. The sucrose analytical values can be greatly decrease during the pre-treatment process. Therefore, differences in analytical methods should be considered when comparing sucrose content and composition.

The Impact of Deficit Irrigation on the Agronomic Performance and Chemical Composition of Scolymus hispanicus L.

In the current study, the effects of drought stress on the growth and phytochemical profile of Scolymus hispanicus L. (a.k.a. golden thistle) were evaluated. Plants were treated with three irrigation regimes, e.g., plants that received only rainwater (Control; C), deficit irrigation (I1; 50% of field capacity (FC)), and full irrigation (Ι2; 100% of FC). The fresh weight of the rosette of leaves was not negatively impacted by deficit irrigation, whereas root development was severely restrained compared to control and I2 treatments. Drought stress conditions had a positive effect on the nutritional properties of the golden thistle since the treatments of control and deficit irrigation showed the highest content of macronutrients and energy. Oxalic acid was the richest organic acid, especially under the I1 regime. Similarly, α-tocopherol was the only identified vitamin E isoform, whose content was also doubled in I1 treatment. Raffinose, glucose, and sucrose were the most abundant free sugars in amounts that varied among the irrigation treatments, while the total and distinct free sugar content was the highest for the I1 treatment. The most abundant detected fatty acid compounds were α-linolenic acid, followed by palmitic and linoleic acid, with the highest amount being detected in C, I1, and I2 treatments, respectively. Flavonoids were the only class of polyphenols detected in golden thistle leaves, including mostly kaempferol and quercetin derivatives. The greatest antioxidant potency was shown for the control and I1 treatments (for OxHLIA and TBARS methods, respectively). The evaluated leaf samples recorded a varied antimicrobial effect for the different bacterial strains and fungi, whereas no cytotoxic, hepatotoxic, and anti-inflammatory effects against the tested cell lines were recorded. Finally, the mineral content of leaves was significantly affected by the irrigation regime, with Ca, Mg, Cu, and Zn being the highest for the I1 treatment, while the I2 treatment had the highest content of K, Fe, and Mn and the lowest Na content. In conclusion, deficit irrigation showed promising results since it improved the phytochemical content without compromising the fresh weight of leaves, and thus it could be suggested as a sustainable agronomic practice for producing high-added value products without significant constraints in growth development and yield parameters of golden thistle.

Health effects of drinking 100% juice: an umbrella review of systematic reviews with meta-analyses.

Low fruit and vegetable intakes are major modifiable determinants of disease. One hundred percent juice may facilitate intake and deliver essential nutrients and bioactive compounds. However, the position of 100% juice in healthy eating guidelines remains controversial due to its lower dietary fiber and higher free-sugar contents compared with whole fruits and vegetables. To conduct an umbrella review of systematic literature reviews with meta-analyses (MAs) to summarize the health benefits of drinking 100% fruit and/or vegetable juice. Four databases (Medline, The Cochrane Library, EMBASE, and CINAHL) were systematically searched for MAs of 100% juice and any health outcomes. Screening, quality, risk of bias, and content overlap tools were applied, and extracted data were narratively synthesized. No eligible studies for vegetable juice were found. Fifteen systematic literature reviews (51 primary MAs, 6 dose-response, and 87 subanalyses; 50-1200 mL/day; hours to years of duration) were included. Ten MAs (19.6%) reported health benefits (4 for blood pressure, 2 for vascular function, 3 for inflammation, 1 for stroke mortality), 3 MAs (5.9%) reported adverse risks (1 each for cardiovascular disease mortality, prostate cancer, type 2 diabetes risk), while most (74.5%) reported no effect (blood lipids, body composition, liver function, metabolic health, cancers, and inflammation). Risks were limited to cohort studies and benefits were found in both cohort and intervention studies. The findings collate evidence showing some potential health benefits associated with 100% juice consumption, with fewer potential risks. The balance of evidence does not support the exclusion of 100% juice from food-based guides to healthy eating, although caution may be warranted in certain groups or individuals, and the body of evidence is not yet conclusive. PROSPERO registration no. CRD42022380588.

Changes in Nutrient Content and Physicochemical Properties of Cavendish Bananas var. Pei Chiao during Ripening

Banana is a typical tropical fruit that is widely cultivated in tropical and subtropical regions, and consumed daily because of its superior nutritional profile. This study aimed to investigate the changes in bananas’ physicochemical properties and nutritional composition from ripening stages 1 to 9. The analysis included color (peel and flesh), texture, total starch content, resistant starch content, free sugar content, minerals (calcium, magnesium, potassium, sodium, iron, phosphorus), and vitamin content. At the same time, the browning enzyme activities of polyphenol oxidase (PPO), peroxidase, oxalic acid, and tannin were also measured. In this study, the banana peel gradually changed from dark green to light green to yellow during the ripening process, eventually appearing with many black spots, while the pulp color changed from white to light yellow and decreased in brightness. The pulp became softer with a prolonged ripening period, which was inconsistent with the time point of peel color change (ripening period 4–5). However, total starch content decreased from 74% to 31%, resistant starch originally at 32% gradually decreased to 5%, and free sugar content gradually increased with increasing ripening period. Vitamin C content and PPO activity decreased significantly during the ripening period, while other vitamins and minerals did not change significantly. In contrast, oxalic acid, tannin content, and peroxidase activity were negatively correlated with the ripening period. Therefore, this study reveals the changes in the nutrient content of bananas at different ripening stages, which may provide helpful information for researchers and producers to identify suitable raw materials for producing stable and high-nutrition-value banana-related foods during the peak raw material abundance seasons while reducing business risk.

Investigating the potential of delignified rice husk as a carbon-rich resource for extracting glucose and its utilization in biocement production through fungal isolates.

Burning rice straw is now a significant issue faced by different regions in India, as its burning releases harmful gases, mainly carbon dioxide. Various techniques are now in trend to utilize the rice straw, e.g., producing compressed natural gas using rice straw, bioethanol, etc., as a substrate for various microorganisms. A high quantity of non-utilized rice husk generates more ideas for its proper utilization. The cellulose, hemicellulose, and lignin found in rice straws can be a fungi growth medium. In this research, the delignification of rice husk is done by acid (2% and 4% H2SO4) and alkali (2% and 4% NaOH) at 121°C at 103kPa for 1h to obtain crude carbon source which is further utilized for biomineralization. The glucose is subjected to qualitative and quantitative analysis using Molisch's and Dinitro salicylic tests. The delignification process showed a positive outcome when 2% H2SO4 is utilized maximum yield of 5.9 ug/ml free sugar concentration. Representing the highest glucose yield compared to the experiment's other acid and base substances used. Various techniques such as field emission-scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and Fourier transformed infra-red (FTIR) spectroscopy are employed to examine surface and chemical alterations. The 2% H2SO4 pretreated rice husk is utilized for microbial-induced calcite precipitation using fungal isolates S1 (3), S1 (18), and S4 (1). The calcite and vaterite produced by biomineralization are confirmed using XRD for fungal isolates namely, S1 (3), S1 (18), and S4 (1) having percentage crystallinity of 59%, 46.428%, and 62.69% percentage crystallinity respectively.

Physico-chemical Properties and Biological Activity of Honey from Two Districts of Tien Giang Province, Vietnam

This study was conducted to determine the physico-chemical properties and biological activity of honey collected from the Tan Phu Dong and Cai Be districts of Tien Giang province, Vietnam. The results showed that the 19% and 20% moisture content honey from Tan Phu Dong district had viscosities of 1075 Cp and 1013.33 Cp, insoluble solid contents of 0.12% and 0.09%, acidities of 32.49 mg/1000 g and 30.49 mg/1000 g, diastase index of 4.5 Schade and 4.09 Schade, free reducing sugar content of 65% and 67%, HMF contents of 0.98 mg/100 g and 0.86 mg/100 g and antioxidant activity of 0.47 and 0.52 mg vitamin C equiv./mg dry wt, respectively. The honey from Cai Be district with 22% moisture content, viscosities, insoluble solid content, acidity, diastase index, free reducing sugar, HMF content and DPPH antioxidant activity displayed as 619 Cp, 0.119%, 46.41 mg/1000 g, 5 Schade, 60.28%, 0.38 mg/100 g and 0.45 mg vitamin C equiv./mg dry wt, respectively.

Exploring the Impacts of Sorghum (Sorghum bicolor L. Moench) Germination on the Flour’s Nutritional, Chemical, Bioactive, and Technological Properties

Germination is a natural, simple, and economical process used to improve the quality of nutritional and technological grains. In this study, native and sprouted sorghum flours were characterized regarding their technological properties (particle size distribution, water, and oil absorption capacity, swelling power and solubility, microscopy of starch granules, and pasting and thermal properties). Nutritional and phytochemical characterization profiles, including free sugars, fatty acids, organic acids, tocopherols, and phenolic compounds, were explored through chromatographic methods. The antioxidant, anti-inflammatory, and cytotoxic activities of the respective hydroethanolic extracts were also evaluated. The results showed that the germination process caused significant changes in the flour composition and properties, causing reduced gelatinization temperature and retarded starch retrogradation; an increased content of free sugars and total organic acids; and a decreased content of tocopherols and phenolic compounds. In terms of bioactivity, the sprouted sorghum flour extract showed better lipid-peroxidation-inhibition capacity and none of the extracts revealed hepatotoxicity or nephrotoxicity, which are important results for the validation of the use of the flours for food purposes. Germination is an efficient and alternative method for grain modification that gives improved technological properties without chemical modification or genetic engineering.

Utilization of Yacon Damaged Roots as a Source of FOS-Enriched Sweet-Tasting Syrup

Damaged yacon roots, often discarded, are a rich source of sweet carbohydrates. In this context, yacon roots from the Hualqui and Crespo varieties were characterized and processed into low-calorie and low-glycemic syrups for sugar reduction in foods. Syrups were obtained using, as technological adjuvants, lemon juice and its most relevant components: citric acid and ascorbic acid. The Hualqui variety was found to be mostly composed of fructose (210 g/kg), while the Crespo variety was rich in inulin (352 g/kg). The use of lemon juice during syrup production promoted the hydrolysis of inulin to fructooligosaccharides and fructose, yielding syrups with competitive relative sweetness (0.52–0.91), glycemic index (0.21–0.40), and caloric values (186–263 kcal/100 g) to commercial syrups. The increase in citric acid concentrations promoted inulin hydrolysis, yielding, at the highest concentration, syrups with higher fructose (333–445 g/kg) and kesto-type fructooligosaccharides (11–85 g/kg) content and lower surface stickiness and stringiness. The addition of ascorbic acid, as an antioxidant agent, decreased by 10% the free sugar content, negatively impacting the sweetness level. These results evidence that fructooligosaccharides-rich syrup can be obtained from yacon-damaged roots with tailored sweetness and low glycemic and caloric properties.

The Effect of Biostimulants on Fruit Quality of Processing Tomato Grown under Deficit Irrigation

Water shortage can be a restrictive factor for the growth and quality of vegetable crops. Considering the alleviating effects of biostimulant application against water stress, this study aimed to investigate the effect of four biostimulant products (protein and amino acids with carboxylic acids (Tr1); protein and amino acids with seaweed extracts (Tr2); humic and fulvic acids with seaweed extracts (Tr3); SiO2 (Tr4); and control (no biostimulants added)) and two irrigation systems (regulated deficit irrigation (RDI)—65% of field capacity and regular irrigation (RI)—100% of field capacity) on quality parameters of processing tomato fruit. Regulated deficit irrigation and biostimulant application increased the energetic value, carbohydrates, and free sugars content, while organic acids showed a variable response to biostimulant use. In terms of tocopherols (α-, β-, γ-, δ-) and carotenoids (lycopene and β-carotene), regular irrigation and biostimulant application negatively affected their content, while Tr3 treatment had a beneficial impact on these lipophilic compounds under RDI conditions. The main fatty acids were palmitic (C16:0) and linoleic (C18:2n6) acids, which increased when plants were treated with Tr3 and Tr1 biostimulants under a deficit regime. Antioxidant activity (assessed by TBARS and OxHLIA assays) and total phenolic and flavonoids content also showed a variable response to the studied factors. In particular, the application of Tr3 and the control treatment under RDI increased the total phenolic content, while the control and Tr3 treatments under the same irrigation regime recorded the highest antioxidant activity. In conclusion, our results indicate that the adoption of eco-friendly strategies such as regulated deficit irrigation and biostimulant application can beneficially affect the quality traits of processing tomatoes.

Effect of sugar reduction on sensory characteristics of dried fish mince product.

Excessive sugar consumption has been linked to type 2 diabetes, obesity and other diseases. Therefore, it is indispensable to reduce sugar of food. However, the sensory characteristics of food are affected after sugar reduction (SR). Currently, SR has been reported in drinks, jams, candies, and other fruit related or sweet foods; but salty or protein related foods have not been explored, therefore there is a big gap that needs to be filled. Sensory scores of initial sweetness and sweetness reduced by 0.26 and 0.12 in 10% SR dried fish mince product compared with control, and there was a small difference between 25% SR (3.33) and 40% SR (3.09) samples. It also showed that 10% SR sample had a small reduction in sweetness value and free sugar content by 3.5% (0.42/11.9) and 7.8% (2.12/27.06) compared with control; while values in 25% SR sample decreased sharply but were not much different from 40% SR sample. Electronic nose results showed that SR had a small effect on odor. Texture analysis showed that texture properties of 25% SR sample were significantly different from control. Dried fish mince product with below 10% SR had a small difference on the sensory characteristics and there was a big change when SR was more than 20%. Dried fish mince product with 25% SR and 40% SR had no significant difference. SR had a small effect on odor, but had a great effect on texture properties, especially over 20% SR. © 2023 Society of Chemical Industry.

Influence of oat flour characteristics on the physicochemical properties of oat-based milk substitutes

This study aimed at investigating the effect of oat composition on the quality characteristics of oat-based milk substitute (OBMS). Raw materials for OBMS consisted of thirty pure cultivar oat flours produced by industrial milling process. The main steps in OBMS preparation included mixing of 10% oat flour with water, starch hydrolysis, solid-liquid separation and formulation of the final product. OBMS was characterised in terms of mass and protein yields, protein content, reducing sugars, particle size, viscosity, dispersion stability and colour. The different composition of oat flours affected the characteristics of the OBMS in terms of mass yield (81.3–88.1%), dry matter yield (56.7–73.8%), protein content (0.63–1.10%), protein yield (31.4–61.6%), content of free reducing sugars (13.1–19.1%), and physical properties including particle size, dispersion stability and viscosity. OBMS mass and dry matter yields correlated positively with both total and damaged starch contents of the oat flour as well as the share of damaged starch of the total starch of the sample, while flour starch content correlated negatively with protein content of OBMS. Protein content of the flour correlated negatively with the mass, dry matter and protein yields and positively with protein content of OBMS. All colour values (L*, a*, b*) of the flour correlated with colour value b* of the OBMS. Protein content and viscosity of OBMS correlated positively with dispersion stability of OBSM. In conclusion, the clear relation between oat composition and the final properties of OBMS suggest relevance of selecting specific oat raw materials to produce good quality OBMS.

생육시기별 양파 전초의 영양 및 기능성 성분과 항산화 활성 비교

Onions are essential vegetables for Koreans’ diet and have various physiological activities. However, problems arise every year due to the imbalance between production and demand. Therefore, in this study, nutritional and functional components, and antioxidant activity were analyzed for each growth period in order to utilize onions at the disposal period. Whole onions harvested before June showed higher values of general ingredients, inorganic ingredients, organic acids, spiraeoside, quercetin, total chlorophyll, and antioxidant activity than bulbs harvested in June. On the other hand, the free sugar content was higher in the bulb of the harvest season in June than in whole onions. The total thiosulfinate content was similar to that of whole onions and bulbs in the early stages of growth. In addition, as a result of comparing the flavonoid compound and antioxidant activity of each onion variety, whole onions harvested at 25 weeks were higher in content than onion bulbs harvested in June. In conclusion, onions before the harvest season in June had excellent utilization value as food. Harvesting before 21 weeks is desirable for growing onions with excellent nutritional value, while harvesting after 23 weeks is recommended for excellent functional components and antioxidant activity in onions.

Enzyme-assisted nanofiltration to enrich tannins from softwood bark extract

Softwood bark is a rich source of renewable chemicals, including phenolic compounds known as tannins. Tannins can be extracted from bark with hot water, but the yield can be relatively low, leading to dilute extracts. Next to tannin, a considerable amount of extracted dry matter comprised of carbohydrates, and bark carbohydrates limit the applicability of the extract in applications that demand high purity. This study used membrane filtration to refine and concentrate tannins produced from hot water extracts of softwood bark. Enzymatic hydrolysis of bark carbohydrates prior to membrane filtration was assessed as means to improve the separation of bark sugars from bark phenols. Enzymatic hydrolysis using an optimised enzyme mixture liberated 55% of bark carbohydrates mainly by degradation of pectin and other polysaccharides in spruce unrefined tannins. Separation of bark phenols from the enzyme-treated extract by precipitation at acidic pH and subsequent microfiltration produced low tannin yield. Instead, keeping bark phenols soluble at alkaline pH allowed us to concentrate them 15-fold with good and stable flux using nanofiltration. Additionally, enzymatically liberated sugars permeated well through the nanofiltration membrane, decreasing the free sugar content of the concentrated tannin from 31% to 7.4%. However, diafiltration did not seem to decrease the proportion of free sugars in the concentrate further. This enzyme-assisted nanofiltration concept was successfully upscaled to a pilot scale which was a promising result for improved industrial applicability of softwood bark tannins in the future.

Effects of postharvest gamma irradiation on quality maintenance of Cara Cara navel orange (Citrus sinensis L. Osbeck) during storage

Gamma irradiation is a non-thermal treatment to effectively eliminate pathogenic microorganisms in citrus production. Here, Cara Cara fruit samples were treated with gamma irradiation (0.3, 0.6, and 0.9 kGy), then their physicochemical quality and antioxidant ability were evaluated for a period of 70 days (d). The irradiated fruit exhibited increases in respiration rate with irradiation dose in the storage period of 0–56 d. During early shelf life (0–42 d), the decay rate of irradiated fruit (0–22%) was higher than that of the control (0–6%) in a dose-dependent manner; while in later shelf life, 0.3 and 0.6 kGy irradiation resulted in lower decay rates. The irradiation showed no significant effect on titratable acidity and total organic acids during storage. Irradiation at 0.6 kGy reduced free sugar content and TSS value, while increased the total phenolic content, DPPH and ABTS values of the fruit at most sampling time points. Considering the reduction of decay rate, respiratory intensity, and weight loss of the fruit under 0.6 kGy irradiation during 56–70 d of storage, 0.6 kGy may be an appropriate radiation dose to maintain the shelf-life quality of Cara Cara fruit, particularly for prolonged postharvest storage.

Effects of packaging and temperature abuse on the quality of red pepper (Capsicum annuum L.) powder.

Storage stability of pepper (Capsicum annuum L.) powder packaged using 2 different film pouches of Ny/PE and PET/Al/PE inserted with moisture absorbent and oxygen scavenger was investigated during storage at 25°C for 5months and at 40°C for 14days. The moisture content of red pepper powder did not change significantly in PET/Al/PE packaging but decreased significantly in Ny/PE packaging after the abuse of storage temperature. The color of red pepper powder was quite stable in all packaging treatments. Other quality characteristics of all packaged pepper powder, including microbial cell count, capsaicinoids, ascorbic acid, and free sugar content, were also maintained near their initial levels with no appreciable changes during storage. Red pepper powder with a moisture content of 13-14% and packaged with a film with high gas-barrier properties can be stored for more than 5months even if there is an unexpected temperature abuse during storage.