Kiwifruit Juice Research Articles

The Effect of Nisin on the Growth and Heat Resistance of Alicyclobacillus acidoterrestris , Alicyclobacillus herbarius and Alicyclobacillus contaminans in Kiwi Juice

In the present study, the effect of nisin on the growth and heat resistance of five isolates and three reference strains from three species of Alicyclobacillus in kiwi fruit juice was investigated. The three Alicyclobacillus acidoterrestris strains and the Alicyclobacillus herbarius isolate C-ZJB-12-55 could multiply below 5 IU/mL of nisin. The growth of all strains could be inhibited by 20 IU/mL of nisin. When no nisin added, the average D90C values of the strains ranged from 12.43 to 37.36 min. The average D90C values decreased with the increase of nisin concentration, and the decrements ranged from 0.41 to 16.48 min for different strains when the concentration of nisin increased to 100 IU/mL. The growth conditions and heat resistance of strains from A. acidoterrestris were the best among test strains, followed by A. herbarius strains. Strains from Alicyclobacillus contaminans could not grow even in kiwi fruit juice without nisin added. Practical Applications Alicyclobacillus are a group of bacteria which can cause the spoilage of juice and beverage products, and nisin is a widely used food preservative. This study first proved that nisin can weaken the heat resistance of the spores of Alicyclobacillus in kiwi fruit juice during the pasteurization procedure, and inhibit the germination of the spores as well as the growth of the germinated vegetative cells during the subsequent procedures. These results would be useful to the kiwi fruit juice industry to control the contamination of Alicyclobacillus and also have practical value for other juice and beverage industries against Alicyclobacillus.

Patulin adsorption of a superior microorganism strain with low flavour-affection of kiwi fruit juice

The aim of this study was to isolate a microbial strain with higher patulin adsorption capability and lower flavour-affection on kiwi fruit juice, and study patulin adsorption behaviour effects on cell morphology and adsorption kinetics. Electronic-nose and physicochemical analysis methods were combined to evaluate the flavour and quality of treated kiwi fruit juice. The results showed that yeasts had a good performance on biomass, patulin adsorption and flavour maintenance. Besides, patulin adsorption behaviour and kinetic study of yeast strain N-10 was investigated, the results showed that patulin adsorption capability was influenced by cell morphology, its adsorption behaviour followed pseudo-first-order reaction kinetics, and equilibrium experiments fit the Langmuir isotherm model. The investigation revealed that patulin adsorption is a spontaneous endothermic physic-sorption behaviour. During adsorption, patulin moved from the liquid to the adsorbent surface and the capability of adsorbents was associated with their cell surface morphology. This study provides a basis for the selection of strains with improved patulin adsorption from kiwi fruit juice and provides the experimental foundation and theoretical basis for future studies of patulin adsorption in fruit juice, it has great potential application for the control of patulin in the juice processing industry.

Bioadsorption of patulin from kiwi fruit juice onto a superior magnetic chitosan

Three different magnetizations of magnetic chitosan were prepared by combining different ratios of Fe3O4 particles and chitosan using Triton X-100 as the emulsifier. The superior magnetic chitosan was selected to conduct the patulin adsorption behavior assay based on the adsorbents granular morphologies, adsorbents recoverability and patulin adsorption efficiency. The results revealed that magnetic chitosan which the ratio of Fe3O4 particles to chitosan is 1:1 was the superior patulin adsorbent with patulin adsorption of 89% and adsorbent recovery of 99.5%. Patulin adsorption study showed that with adding 100 mg magnetic chitosan into 10 mL 200 μg/L patulin contaminated kiwi fruit juice for 9 h at 35 °C, patulin adsorption capability reached the maximum of 19.4 μg/g. Also, its paulin adsorption behavior followed pseudo-second-order process and was fitted well with Langmuir isotherm model. Furthermore, magnetic chitosan application research indicated that the quality and flavor of kiwi fruit juice was without any change except color and luster better than before. This study furnished an excellent paulin adsorbent for its great potential application in juice processing industry.

Development and quality evaluation of bitter gourd- Kiwi blended squash during storage

Bitter gourd fruit (Momordica charantia L.) contains many nutraceutical compounds and possess antioxidant and hypoglycemic activity but, its utilization in foods products has not received much attention. Efforts were made to prepare antioxidant rich palatable bitter gourd based functional squash by blending bitter gourd juice with kiwi fruit (Actinidia deliciosa) juice in different ratios viz. 90:10, 80:20, 70:30, 60:40 and 50:50 using different levels of fruit part (25, 30 and 35%) and TSS (40 and 45°B) separately. Among different combinations, the squash prepared using 30% blended juice of treatment T32 (80% bitter gourd juice+20% kiwi juice) with 45°B TSS recorded highest sensory scores. The developed products were analyzed for their bio-chemical, antioxidant potential and sensory quality characteristics at different storage intervals (0,3 and 6 months). The bitter gourd- kiwi blended squash contained 44.83°B TSS, 1.25% acidity and 37.54% total sugars. Blending has increased ascorbic acid content (33%) and total phenolics (24%) of the blended beverage over bitter gourd squash. The products exhibited only slight changes in their physico-chemical, nutritional and sensory characteristics during storage, yet were shelf-stable and remained acceptable up to a period of six months. The high antioxidant potential (68.29%) of the developed product compared to the control sample revealed its health benefits.

Individual and Combined Effects of Pomegranate Extract and Ultrasonic Treatments on Kiwifruit Juice Quality Parameters

AbstractThe objectives of this study were to report the effectiveness of ultrasound and pomegranate extract, individually and combined, on kiwifruit juice quality attributes. Fruit juices were treated with 180 μg/mL pomegranate extract and sonicated for 10 and 30 min (180 W, 40 kHz). Microbial populations, ascorbic acid retention, sensory attributes and color parameters were evaluated through refrigerated storage. By the end of storage, individual ultrasound treatments were able to reduce yeast and molds counts compared with that in control. Furthermore, combined treatments of ultrasound and pomegranate extract showed synergism, with higher reductions on yeast and molds. None of the treatments were able to increase the ascorbic acid retention through storage time. Color parameters evaluated showed that the treatments applied had significant differences from that of control. At Day 2, the treatments showed an improvement in color, with total color difference (ΔE) lower than that of untreated sample, indicating less color difference from fresh kiwifruit juice. Sensory attributes were not significantly affected by the treatments. However, a significant effect of storage time was perceived by the panelists, with a decrease in overall visual quality score throughout time, indicating the end of shelf‐life of the product at Day 7 of refrigerated storage.Practical ApplicationsUltrasonic processing technology and the application of natural antimicrobials are continuously being explored as alternatives to traditional thermal treatments in the food industry. It is necessary to study the impact of these technologies both individually and combined, in terms of microbiological stability and quality preservation. In practice, it is important to not only decrease the microbial growth on food products, but also minimize the loss of their nutritional and sensory attributes. This study suggests some processing and preservation conditions for kiwifruit juice, demonstrating the potential use of ultrasound in combination with the application of pomegranate extract as a biopreservative. This hurdle technology could be easily introduced in the fruit and vegetable juice industry, replacing thermal treatments that compromise the nutritional and sensory quality of the final product.

Purification and characterization of a thermostable endo-beta-1,4 mannanase from Weissella viridescens LB37 and its application in fruit juice clarification

The isolation and characterization study of lactic acid bacteria was performed with a sample of fermented sausage, which was collected from a local market in Erzurum. As a result of sequencing analysis of 16S rRNA, this bacterium is found to be similar to Weissellaviridescens (GenBank No: KM365459) at a ratio of 99 %. β-Mannanase was purified 188.07 times from W. viridescens by using ammonium sulfate precipitation, ion exchange chromatography and then employing gel filtration chromatography techniques. The purified enzyme has shown only a protein band at a level of 36.25 kDa with SDS-PAGE. The mannanase obtained after these purification steps has shown maximum activity at pH 5 and 40 °C, and the enzyme was determined to be quite stable within the range of pH 2–11 when temperature is higher than 50 °C. The activator or inhibitor effects of ions such as Cu2+, Fe2+, Ca2+, Mg2+ and Zn2+ on activity of mannanase were also researched, and all metal ions except Ca2+ significantly affected enzyme activity in a positive direction. Vmax and Km values of mannanase for locust bean gum were 82.5 mg mannan/mL and 0.0178 mM. In addition, considering the biotechnological aspect, clarification of fruit juice was investigated. The purified enzyme was determined to be the most effective enzyme that can be used in clarifying the kiwi juice with a ratio of 117.21 %.

Detection of Alicyclobacillus spp. in Fruit Juice by Combination of Immunomagnetic Separation and a SYBR Green I Real-Time PCR Assay.

An approach based on immunomagnetic separation (IMS) and SYBR Green I real-time PCR (real-time PCR) with species-specific primers and melting curve analysis was proposed as a rapid and effective method for detecting Alicyclobacillus spp. in fruit juices. Specific primers targeting the 16S rDNA sequences of Alicyclobacillus spp. were designed and then confirmed by the amplification of DNA extracted from standard strains and isolates. Spiked samples containing known amounts of target bacteria were used to obtain standard curves; the correlation coefficient was greater than 0.986 and the real-time PCR amplification efficiencies were 98.9%- 101.8%. The detection limit of the testing system was 2.8×101 CFU/mL. The coefficient of variation for intra-assay and inter-assay variability were all within the acceptable limit of 5%. Besides, the performance of the IMS-real-time PCR assay was further investigated by detecting naturally contaminated kiwi fruit juice; the sensitivity, specificity and accuracy were 91.7%, 95.9% and 95.3%, respectively. The established IMS-real-time PCR procedure provides a new method for identification and quantitative detection of Alicyclobacillus spp. in fruit juice.

Microfiltration of kiwifruit juice and fouling mechanism using fly-ash-based ceramic membranes

Three different low-cost inorganic membranes prepared from fly-ash precursor have been used for the clarification of centrifuged kiwifruit juice. The prepared membranes have been characterized by SEM analysis, average pore diameter and porosity determinations, and pure water permeation experiments. Dead-end microfiltration experiments have been performed on centrifuged kiwifruit juice to evaluate the effect of pore diameters (dm) and porosities (ɛ) on the permeation characteristics (permeate flux and juice quality). A membrane of pore diameter 1.25μm proved to be optimal for the clarification of kiwifruit juice. Different membrane pore blocking models have been used to analyze the observed decline in permeate flux. Analysis of the fouling mechanism results has revealed that the three membranes were controlled by different filtration mechanisms.

KIWIFRUIT PROCESSING STUDIES

The kiwifruit is unique because of its high nutritional content, different flavours, vitamins, minerals, antioxidants, phytochemicals and fibre content. In terms of nutrient content, the kiwifruit is amongst the richest fruits: it is also very valuable in terms of health. It is usually consumed fresh but in recent years along with increased production, industrial use is increasing. It is used in the canned food industry, for marmalades, fruit sauces and candies and for fruit juice concentrates, either separately or mixed with strawberries or apples. The fruit is also canned, dried, frozen, and used for the preparation of nectars. In addition, kiwifruit are used in the cosmetic industry for production of lip balm, aromas, soap, shampoo, shower gel, and other products. However, most kiwifruit are eaten fresh and only a small proportion of the crop is processed. There are several reasons why kiwifruit processing has not developed further. The main problem is the characteristics of the fresh fruit: the instability of these characteristics means that standard processing technologies cannot be used. New processing options that are now being tested by different researchers include low temperature extraction, hot air-vacuum drying, high-pressure processing, UV-treatment, pervaporation, and rapid sterilisation. In particular, different techniques are used to remove polyphenols from kiwifruit juices during processing and storage. The effects of these techniques on the preservation of the health attributes, especially those due to polyphenols, micronutrients, aroma and volatile compounds are being investigated. In this study, different processing studies conducted by different researchers in Turkey and the rest of the world are examined in detail as a guide to further work.

Effect of Yeast Cell Morphology, Cell Wall Physical Structure and Chemical Composition on Patulin Adsorption.

The capability of yeast to adsorb patulin in fruit juice can aid in substantially reducing the patulin toxic effect on human health. This study aimed to investigate the capability of yeast cell morphology and cell wall internal structure and composition to adsorb patulin. To compare different yeast cell morphologies, cell wall internal structure and composition, scanning electron microscope, transmission electron microscope and ion chromatography were used. The results indicated that patulin adsorption capability of yeast was influenced by cell surface areas, volume, and cell wall thickness, as well as 1,3-β-glucan content. Among these factors, cell wall thickness and 1,3-β-glucan content serve significant functions. The investigation revealed that patulin adsorption capability was mainly affected by the three-dimensional network structure of the cell wall composed of 1,3-β-glucan. Finally, patulin adsorption in commercial kiwi fruit juice was investigated, and the results indicated that yeast cells could adsorb patulin from commercial kiwi fruit juice efficiently. This study can potentially simulate in vitro cell walls to enhance patulin adsorption capability and successfully apply to fruit juice industry.

Determination of the Optimum Conditions in Evaluation of Kiwi Juice as Green Corrosion Inhibitor of Steel in Hydrochloric Acid

Determination of the Optimum Conditions in Evaluation of Kiwi Juice as Green Corrosion Inhibitor of Steel in Hydrochloric Acid

Application of Membrane Separation in Fruit and Vegetable Juice Processing: A Review

Fruit and vegetable juices are used due to convenience. The juices are rich in various minerals, vitamins, and other nutrients. To process the juices and their clarification and/or concentration is required. The membranes are being used for these purposes. These processes are preferred over others because of high efficiency and low temperature. Membranes and their characteristics have been discussed in brief for knowing suitability of membranes for fruit and vegetable juices. Membrane separation is low temperature process in which the organoleptic quality of the juice is almost retained. In this review, different membrane separation methods including Microfiltration, Ultrafiltration, and Reverse osmosis for fruit juices reported in the literature are discussed. The major fruit and vegetable juices using membrane processes are including the Reverse osmosis studies for concentration of Orange juice, Carrot juice, and Grape juice are discusses. The Microfiltration and Ultrafiltration are used for clarification of juices of mosambi juice, apple juice, pineapple juice, and kiwifruit juice. The various optimized parameters in membranes studies are pH, TAA, TSS, and AIS. In this review, in addition to above the OD is also discussed, where the membranes are used.

Rapid and convenient synthesis of stable silver nanoparticles with kiwi juice and its novel application for detecting protease K

Stable AgNPs were synthesized by a facile approach, and further developed as a colorimetric nanoplatform for selectively detecting protease K.

Spray-Drying of Green or Gold Kiwifruit Juice–Milk Mixtures; Novel Formulations and Processes to Retain Natural Fruit Colour and Antioxidants

This study describes novel formulations and approaches to produce reconstitutable (in water) spray dried kiwifruit milk powders that possess the intrinsic fruit colour and antioxidants of kiwifruits. Novel feed formulations, containing the aqueous fraction of green or gold kiwifruit puree, skim milk, fortifying zinc (in the form of zinc citrate) and a minimal amount of maltodextrin (3 % w/w), were spray dried at a relatively low inlet temperature (150 °C) to produce kiwifruit juice–milk powders with good dissolution efficiency (complete dissolution in 21–28 s), low water activity (0.22–0.28) and high retention of vitamin C, phenolics and carotenoid antioxidants. Both the green and gold kiwifruit juice–milk powders were pseudoplastic-like materials. Their reconstituted aqueous solutions had viscosity of 2–23 mPa · s and exhibited a shear rate dependence. Adding kiwifruit pulp residue to the feed solution at a mass ratio of 25:75 significantly enhanced the dissolution efficiency and the natural kiwifruit colour of the product powders without affecting the total phenolic and vitamin C contents. Preheating the feed solution to 50 °C for 1 min had a positive impact on the physicochemical attributes and bioactive profile of kiwifruit juice–milk powders, including a greater retention of initial kiwifruit juice colour, lower water activity, better dissolution efficiency and a higher total phenolic content. The powders obtained in this study contain multiple health-promoting nutrients and bioactives including kiwifruit antioxidants and milk proteins, and can be used in beverages or as functional ingredients for nutraceutical applications.

Alteration of Porcine Serum Albumin Levels in Pork Meat by Marination in Kiwi or Pineapple Juice and Subsequent Pan Broiling.

This study was conducted to evaluate the changes in porcine serum albumin (PSA), a major allergen, which occur when raw pork ham is marinated with kiwi or pineapple juice, and/or when the ham is pan broiled at 300℃ for 4 min after marination. In this study, raw pork ham was soaked for 4 h or 8 h in marinades containing commercial marinating sauce only, commercial marinating sauce and 7% kiwi juice, or commercial marinating sauce and 7% pineapple juice. When the meat was marinated and then pan-broiled, pork ham meat protein was significantly denatured and hydrolyzed, and the level of PSA in the meat was significantly reduced. The PSA contents of pork broiled without marination, pork that had been marinated in commercial marinating sauce alone, pork that had been marinated in commercial marinating sauce with kiwi juice, and pork that had been marinated in commercial marinating sauce with pineapple juice, were 95.4, 43.3, 14.3, and 5.4 ng/mL, respectively (p<0.05). Marinating with pineapple juice was more effective than marinating with kiwi juice; and marination for 8 h was more effective than marinating for 4 h. These results indicate that the level of PSA in pork ham is effectively reduced, when the meat is first marinated in sauces that contain kiwi or pineapple extracts for 8 h, rather than 4 h, and then cooked. Further study is needed to determine whether marinated pork meat reduces allergenicity in vivo, as well.

Wild edible plants as potential antioxidant or nutritional supplements for beverages minimally processed

Wild edible plants (WEP) with high antioxidant capacity, Rosa canina fruits, Quercus ballota acorns and Sanguisorba minor (young leaves and stems), were added to orange and kiwifruit juices for increase the nutritional properties. The addition of WEP to orange juice (OJ) and kiwifruit cremogenate (KC) does not affect, or it can even improve, some parameters of consumer's acceptance, although the mixtures increasing sweetness and intensifying the matrix colour without changing the tone are the best valued. The beverages minimally processed with higher TSS were the matrices fortified with Q. ballota, the same that were considered sweetest by the judges. The addition of WEP to OJ did not significantly change the levels of vitamin C (ascorbic acid plus dehydroascorbic acid). The addition of R. canina and S. minor increased the content of phenolic compounds and antioxidant capacity in both matrices (OJ and KC) in more than 30%. Beverages with a high interest for consumers and with high antioxidant properties have been obtained.

Green Synthesis of Silver Nanoparticles at Room Temperature Using Kiwifruit Juice

ABSTRACT Comparing with physical and chemical methods, green synthesis techniques are emerging as facile and eco-friendly methods for the synthesis of silver nanoparticles. In this work, we demonstrated the biological synthesis of silver nanoparticles by the reduction of silver ions using kiwifruit juice as the reducing and stabilizing reagent. From the evidence of ultraviolet-visible spectroscopy and transmission electron microscopy, different sizes of silver nanoparticles were formed when the juice volume, reaction temperature, and reaction time were altered with respect to 0.01% silver acetate solution. The synthesized silver nanoparticles were stable for more than 1 month. Transmission electron microscopy studies showed the silver nanoparticles synthesized in room temperature have the diameters in the range of 5–25 nm. The proposed synthesis method is green and low cost, and the synthesized silver nanoparticles have potential bioanalytical applications.

An immunomagnetic separation-real-time PCR system for the detection of Alicyclobacillus acidoterrestris in fruit products

Alicyclobacillus acidoterrestris is the most important spoilage species within the Alicyclobacillus genus and has become a major issue in the pasteurized fruit juice industry. The aim of this study was to develop a method combining immunomagnetic separation (IMS) with real-time PCR system (IMS-PCR) for rapid and specific detection of A. acidoterrestris in fruit products. A real-time PCR with the TaqMan system was designed to target the 16S rDNA genes with specific primer and probe set. The specificity of the assay was confirmed using 9 A. acidoterrestris strains and 21 non-A. acidoterrestris strains. The results indicated that no combination of the designed primers and probe was found in any Alicyclobacillus genus except A. acidoterrestris. The detection limit of the established IMS-PCR was less than 10CFU/mL and the testing process was accomplished in 2–3h. For the three types of samples (sterile water, apple juice and kiwi juice), the correlation coefficient of standard curves was greater than 0.991, and the calculated PCR efficiencies were from 108% to 109%. As compared with the standard culture method performed concurrently on the same set of samples, the sensitivity, specificity and accuracy of IMS-PCR for 196 naturally contaminated fruit products were 90.0%, 98.3% and 97.5%, respectively. The results exhibited that the proposed IMS-PCR method was effective for the rapid detection of A. acidoterrestris in fruit products.

Comparison of effect of microwave sterilization and pasteurization on qualities of kiwi juice

This study was conducted to investigate the comparison of effects of microwave sterilization and pasteurization on nutrient components and physio-chemical properties of kiwi juice based on the achievement of commercial sterilization requirements separately. “Gui Chang” kiwi, produced from Xiuwen in Guizhou Province, which was used as raw materials for processing, and the effects of microwave sterilization and pasteurization on total number of bacteria, pH value, soluble solid content, color, total acid, total sugar, polyphonols, VCand SOD in kiwi juice were determined. The results showed that different sterilization methods had no significant effect on pH, soluble material, total sugar and total acid (p>0.05) when compared with control group. The content of VCin kiwi juice decreased after pasteurization (p 0.05) after microwave sterilization. Those indicated that microwave sterilization could better maintain the color and nutrients in kiwi juice. Therefore, microwave sterilization technology not only achieved good bacterial effect but also to ensure maximum quality of kiwi juice.

A kiwi juice aqueous solution as coagulant of bovine milk and its potential in Mozzarella cheese manufacture

In this work a kiwi juice aqueous solution was prepared and used as coagulant enzyme in the manufacturing process of mozzarella cheese. The aqueous solution does exhibit high levels of milk-clotting activity probably due to the presence of the clotting enzyme actinidin in mixture with other kiwi fruit proteolityc enzymes. The mozzarella cheese was manufactured from bovine milk with a yield of 10.6% being in the range of that routinely obtained during cheese manufacture. A preliminary evaluation of the cheeses flavor showed positive results and lack of bitterness. Finally, in view of a future marketing of the kiwi juice aqueous solution as plant coagulant, it is shown that the aqueous solution stored for 20 days at −20°C maintains both the clotting and proteolytic activities unaffected. Due to its properties as well as to the accessibility of the primary source for the preparation of the aqueous solution, it might represent a good candidate for calf rennet substitution, provided that further research on cheese properties will be carried out.