Flavor and texture of banana chips dried by combinations of hot air, vacuum, and microwave processing

Analysis of physicochemical properties of nut-based milk and sweetened condensed milk alternatives

This study analyzed the physicochemical properties of nut-based milk and sweetened condensed milk (SCM) alternatives. Four types of nuts (almonds, cashews, hazelnuts, and walnuts) were roasted at 140 °C for 15 min, followed by the preparation and analysis of milk and SCM alternatives. During the production of SCM by heating with adding sugar, the pH, moisture, and L* decreased, while the carbohydrates, viscosity, and browning index increased significantly (p < 0.05). Oleic acid, linoleic acid, and linolenic acid contents were comparable among all samples (p > 0.05). Volatile compounds were analyzed using HS-SPME-GC-MS to determine changes due to roasting and heating, and a total of 54 volatile compounds were identified. These findings to show the importance of the physicochemical characteristics of milk and SCM alternatives, provide practical information for the development of improved-quality dairy alternatives.

Changes in, and correlation analysis of, volatile compounds, key enzymes, and fatty acids in lemon juice vesicles during freeze drying and hot-air drying

BACKGROUND

Lemon juice vesicles are distinguished by their unique and abundant volatile flavor compounds, which can undergo complex changes during drying. In this study, integrated freeze drying (IFD), conventional freeze drying (CFD), and hot-air drying (AD) were used to dry lemon juice vesicles to investigate the changes in, and correlations among volatile compounds, fatty acids, and key enzyme activity during the drying process.

RESULTS

Twenty-two volatile compounds were detected during the drying processes. Compared with fresh samples, seven compounds were lost in the dried samples after IFD, seven after CFS, and six after AD, and the loss rates of the total content of volatile compounds in the dried samples were 82.73% in CFD, more than 71.22% in IFD, and more than 28.78% in AD. In total, 1.015 mg/g of seven fatty acids were detected in the fresh samples; the content loss rates of total fatty acids after drying were 67.68% in AD, more than 53.00% in CFD, and more than 36.95% in IFD, respectively. During the three drying processes, IFD retained relatively higher enzyme activity in the samples.

CONCLUSION

Many positive and negative correlations (P < 0.05) were observed among the key enzyme effects, fatty acids, and volatile compounds, showing close associations. The current work provides information that is important for the selection of suitable drying techniques for lemon juice vesicles and suggests how to control their flavor during the drying process. © 2023 Society of Chemical Industry.

Edible gum addition improves the quality of freeze-dried restructured strawberry blocks

Freeze-dried restructured strawberry blocks (FRSB) have become an increasingly popular product. In this study, the effects of six edible gums (guar gum, gelatin, xanthan gum, pectin, konjac gum, and carrageenan) on the FRSB quality were investigated. For FRSBs, compared with those in untreated samples, the 0.6 % guar gum addition increased texture profile analysis (TPA) hardness, chewiness, and puncture hardness by 29.59%, 174.86%, and 25.34%, respectively; after the 0.6% gelatin addition, the sensory evaluation sourness was reduced by 8.58%, whereas yield, TPA chewiness, and puncture hardness were increased by 3.40%, 28.62%, and 92.12%, respectively; with the 0.9% gelatin addition, the sensory evaluation sourness was reduced by 8.58%; with the 0.9% pectin addition, the yield, TPA hardness, chewiness, and puncture hardness were increased by 4.55%, 5.94%, 77.49%, and 103.62%, respectively. In summary, 0.6-0.9% pectin, gelatin, and guar gum addition are recommended to improve the main qualities of FRSBs.

Novel insight into the evolution of volatile compounds during dynamic freeze-drying of Ziziphus jujuba cv. Huizao based on GC-MS combined with multivariate data analysis

To understand the evolution of aroma in jujubes during dynamic freeze drying (FD), the relationship between aroma compounds, precursors, and related enzyme activities were analyzed. Fifty-three volatiles were identified during FD processing. After FD, the total aroma contents were increased from 11,004 to 14,603 μg/kg, ketones content was significantly decreased by 54.11 %, resulted in the loss of creamy note in freeze-dried jujube (FDJ). Through the network analysis, serine, glycine, proline, valine, cysteine, arginine, glutamic acid, lysine and leucine had the significant correlation with pyrazines, dominated the roasty note of FDJ. Linoleic acid, α-linolenic acid and oleic acid with lipoxygenase had important effects on the increase of esters (from 412 to 9,486 μg/kg), contributed fruity and sweet notes of FDJ. Besides, through the Mantel test, the influence degree of factors on the formation of FDJ aroma was ranked as temperature > enzyme activity > fatty acids > amino acids.

Study on Quality Change and Processing Suitability Evaluation of the Low-Temperature Vacuum Frying of Bananas

The banana quality evaluation system is not sufficiently mature in China and cannot meet the demand of producing high-quality processed banana products. In order to screen banana varieties suitable for low-temperature vacuum frying and extend the banana deep processing industry chain, banana slices from 15 varieties planted in China were prepared by low-temperature vacuum-frying (VF) technology in the present study. After factor analysis on 20 indicators of sensory, flavor, nutritional and processing quality from different varieties of banana slices, comprehensive quality evaluation models were constructed for banana slices. It was concluded that Meishijiao No. 1 had the highest overall score among the 15 banana varieties; hence, it was deemed suitable for processing. Meanwhile, in order to investigate the difference between flavor substances in banana slices before and after processing, a flavor histology study was conducted with solid-phase microextraction (SPME) and comprehensive two-dimensional gas chromatography coupled to time-of flight mass spectrometry (GC×GC-TOFMS). It was found that the content differences of 2,3-pentanedione, hexanal and pentanal may cause the weakened fruitiness and the increased oil flavor of banana taste.

Dynamic Changes in Volatile Flavor Compounds, Amino Acids, Organic Acids, and Soluble Sugars in Lemon Juice Vesicles during Freeze-Drying and Hot-Air Drying

Lemon juice vesicles have abundant flavor components that can undergo complex changes during drying. Three drying methods, including integrated freeze-drying (IFD), conventional freeze-drying (CFD), and hot-air drying (AD), were studied to determine their effects on the dynamic changes in the flavor compounds in lemon juice vesicles. Compared with the fresh samples, the final dried samples that underwent IFD, CFD, and AD lost seven, seven, and six volatile flavor compounds and three, four, and five amino acids, respectively; the order of the loss ratios with respect to the volatile compound content was: 82.73% in CFD > 71.22% in IFD > 28.78% in AD. AD resulted in the highest total amino acid content (10.83 ± 0.20 mg/g), which was 1.39 and 5.54 mg/g higher than that of IFD and CFD, respectively; CFD resulted in the highest total organic acid content (45.94 ± 0.34 mg/g), which was 8.01 and 7.87 mg/g higher than that of IFD and AD, respectively; and AD contributed to the highest total soluble sugars (17.12 ± 0.20 mg/g), which was 1.24 and 1.49 mg/g higher than that of IFD and CFD, respectively. A correlation analysis demonstrated that most of the amino acids and the soluble sugars were closely related to the profiles of the volatile compounds in the lemon juice vesicles during drying.

Life cycle environmental impacts of fruits consumption in the UK

Fruits are indispensable for a balanced and healthy diet. However, their environmental impacts remain largely unknown. Using a life cycle approach, this work estimates for the first time the impacts of fruits consumed in the UK. What makes the UK a particularly interesting case is that only 7% of fruits are produced domestically, with the rest imported, largely (70%) from outside of Europe. In total, 21 types of fruit and 46 fresh and processed products produced in the UK and abroad are considered to estimate the impacts at both the product and the national levels. The findings at the product level suggest that melons have the lowest and mangoes and avocados the highest impacts as a significant portion of the last two is air-freighted. Processing leads to high impacts of fruit juices, dried and frozen products. Storage has a considerable contribution to the impacts for fruits stored over a long period, such as apples. Packaging used for canned fruits and juices is also a significant contributor to the impacts. Taking the annual consumption into account, the whole UK fruit sector generates 7.9 Mt CO₂ eq. and consumes 94 PJ of primary energy. This is equivalent to 4% of the annual GHG emissions and 9% of energy demand of the whole UK food sector. Moreover, fruits require 0.35 Mha of agricultural land and 315 Mm³ eq. of water per year. Oranges, bananas and apples are responsible for more than half of the impacts at the national level as they account for 64% of the total fruit consumption in the UK. It is expected that the results of this study will be of interest to different supply chain actors, including farmers, food processors and consumers, aiding them in reducing the environmental impacts of fruits.

Effect of Vacuum Impregnation on Drying Kinetics and Selected Quality Factors of Apple Cubes

The possibility of using the vacuum impregnation as a pretreatment before drying apple cubes was investigated. The impregnation was carried out for 4.5 min with the vacuum pressure of 0.01 MPa. The sucrose solution or a mixture of sucrose and the citric acid were used as infiltration liquids. Apple cubes were dried by convective drying (CD) (at temperature of 50 and 70 °C) or microwave-vacuum drying (MVD) (at power of microwaves 120 and 480 W). The drying kinetics was determined and quality factors (anti-oxidant activity, mechanical–rheological properties and colour changes) were analysed. Studies proved that the vacuum impregnation causes increasing of the drying dynamics (12.50–28.57 % during CD and 12.50–18.48 % during MVD). All impregnated apples were darker, yellower and susceptible for deformation or cutting than non-impregnated. The highest level of anti-oxidant activity was observed when two-component impregnant before MVD by power of 480 W was used.

A critical review on the spray drying of fruit extract: effect of additives on physicochemical properties

Spray drying accomplishes drying while particles are suspended in the air and is one method in the family of suspended particle processing systems, along with fluid-bed drying, flash drying, spray granulation, spray agglomeration, spray reaction, spray cooling, and spray absorption. This drying process is unique because it involves both particle formation and drying. The present paper reviews spray drying of fruit extracts, such as acai, acerola pomace, gac, mango, orange, cactus pear, opuntia stricta fruit, watermelon, and durian, and the effects of additives on physicochemical properties such as antioxidant activity, total carotenoid content, lycopene and β-carotene content, hygroscopy, moisture content, volatile retention, stickiness, color, solubility, glass transition temperature, bulk density, rehydration, caking, appearance under electron microscopy, and X-ray powder diffraction. The literature clearly demonstrates that the effect of additives and encapsulation play a vital role in determining the physicochemical properties of fruit extract powder. The technical difficulties in spray drying of fruit extracts can be overcome by modifying the spray dryer design. It also reveals that spray drying is a novel technology for converting fruit extract into powder form.

Banana cultivars, cultivation practices, and physicochemical properties

The physicochemical (pH, texture, Vitamin C, ash, fat, minerals) and sensory properties of banana were correlated with the genotype and growing conditions. Minerals in particular were shown to discriminate banana cultivars of different geographical origin quite accurately. Another issue relates to the beneficial properties of bananas both in terms of the high dietary fiber and antioxidant compounds, the latter being abundant in the peel. Therefore, banana can be further exploited for extracting several important components such as starch, and antioxidant compounds which can find industrial and pharmaceutical applications. Finally, the various storage methodologies were presented with an emphasis on Modified Atmosphere Packaging which appears to be one of the most promising of technologies.

An evaluation of the maximized survey-derived daily intake (MSDI) as a practical method to estimate intake of flavouring substances

Realistic estimates of intake are essential for risk assessments of flavouring agents, since substantial over or underestimations introduce inaccuracies into such evaluations. The objectives of this study were to examine the relationship between intakes estimated using methods based on the reported volume of production [e.g., maximized survey-derived daily intake (MSDI)] versus use-level data [e.g., possible average daily intake (PADI) and modified theoretical added maximum daily intake (mTAMDI)]. The impact of volatility, self-limiting organoleptic properties and whether 10% of the population are eaters, an assumption in the MSDI calculation, on intake estimates were investigated. Analyses on 221 flavouring substances showed that intake estimates derived from MSDI correlated with values determined from detailed 14-day menu-census data, PADI, and mTAMDI. Comparisons of menu-census intake data adjusted to account for factors such as volatile losses showed that MSDI estimates are realistic and sufficiently conservative, whereas mTAMDI results in substantial overestimates of intake. Very few flavours have less than 10% eaters, and in the worst case, this assumption underestimates percent eaters by a factor of about 4. This investigation supports the use of MSDI as a conservative yet practical method to estimate intake of flavouring substances.