Pear Puree Research Articles

Evaluation of High-Pressure Processing (HPP) for the Stabilization of Prickly Pear Puree through the Assessment of Its Microbiological, Enzymatic, and Nutritional Features

Evaluation of High-Pressure Processing (HPP) for the Stabilization of Prickly Pear Puree through the Assessment of Its Microbiological, Enzymatic, and Nutritional Features

The Survival of Salmonella enterica Strains in Ready-to-Eat Fruit Purees under Different Storage Temperatures

Salmonella enterica, known for its resilience to acidic environments, has been linked to foodborne outbreaks of illness from fruit derivatives. This study aimed to assess the survival of five serovars of Salmonella enterica subsp. enterica in various fruit purees subjected to different storage temperatures. Among the studied serovars, S. enteritidis exhibited the most significant population decrease in all fruit purees. In contrast, S. Agona, S. Gaminara, S. Michigan, and S. Montevideo survived in peach puree at 4 °C for at least 3 days, and S. Agona, S. Gaminara, and S. Montevideo maintained their initial levels in pear puree under the same time/temperature conditions. However, none of the strains were detectable in plum and black currant purees after 2 days at 4, 15, or 25 °C. These findings highlight variations in the behaviour of S. enterica serovars within different fruit purees. Likewise, low-temperature conditions prolonged the survival of the tested strains in all fruit purees analysed.

Optimization of Hydrothermal Treatment Conditions for Pear Puree Using the Response Surface Methodology

Optimization of Hydrothermal Treatment Conditions for Pear Puree Using the Response Surface Methodology

Survival of Escherichia coli O157, Salmonella, and Listeria monocytogenes in Ethanol and Juice Mixtures at Ambient Temperature

Some bars and restaurants have begun displaying alcoholic fruit and vegetable cocktail mixes at ambient temperature. Operators often believe that ethanol makes this practice safe, and conversely, some regulators question the safety. It has been reported that ethanol may inhibit the growth of some bacteria at concentrations starting at 8–10% and may be biocidal at concentrations ≥30%. In this study, Escherichia coli O157, Salmonella,and Listeria monocytogenes did not grow in bananapuree, pear puree, orange juice, and apple juice cocktailmixtures prepared with ethanol concentrations from 10to 50% at 25°C. Inoculated pathogens were not detectedin juice plus ethanol at 40 or 50% after 48 h. Juices withethanol concentrations of 10–30% exhibited different logreductions over time for each of the pathogens introduced.This study has implications for how regulators assess therisk of ethanol juice mixtures held at ambient temperatureunder the U.S. Food and Drug Administration (FDA) FoodCode. Operators that desire to display ethanol and fruitjuice mixtures at room temperature need to ensure a pH< 4.2 or a combination of pH and water activity values based on Table B of the FDA Food Code, or they must keep the product under refrigeration at a temperature ≤ 41°F.

Control of Enzymatic Browning in Strawberry, Apple, and Pear by Physical Food Preservation Methods: Comparing Ultrasound and High-Pressure Inactivation of Polyphenoloxidase.

Polyphenoloxidase (PPO) enzyme can be found in fruits, vegetables and crustaceans. Its activity, promoted by oxygen, causes food browning with subsequent loss of quality and limited shelf life. Foods are pasteurized with conventional and novel physical methods to inactivate spoilage enzymes, thus avoiding the addition of unhealthy chemical preservatives. Ultrasound and high- pressure processing (HPP) are non-thermal technologies capable of retaining vitamins, bioactives and sensory components of fresh fruits. Enzyme residual activity vs. processing time were plotted for strawberry, apple, and pear purees subjected to thermosonication (1.3 W/g—71 °C), HPP-thermal (600 MPa—71 °C) and heat treatment alone at 71 °C. The PPO residual activities after treatments were highly variable. TS was the most effective for inactivating PPO, followed by thermal processing. HPP-thermal did not improve the inactivation compared with thermal treatment at 71 °C. The resistance of the three fruits’ PPOs exhibited the same pattern for the three technologies: pear PPO was the most resistant enzyme, followed by apple PPO and, lastly, strawberry PPO. However, the resistance of the three PPOs to TS was lower and very similar. Given the huge variability of PPO resistance, it is important to run inactivation tests for different fruits/cultivars. The results can assist manufacturers to avoid browning during processing, storage and distribution of fruit purees, juices and concentrates.

Dependence of surface tension of fruit puree on temperature exposure

When developing food products with new properties using innovative technologies, it is important to obtain data on the physicochemical, thermal-physical and structural-mechanical properties of the processed food media. So, one of the key components in the selection of the mode of collapsing ultrasonic cavitation is the surface tension of vegetable purees. The paper presents research data (2020) on the effect of temperature on the surface tension coefficient of fruit puree of different viscosity. The objects of research are cherry plum, pear and apple puree, combined in a row by viscosity. The surface tension coefficient was determined by the stalagmometric method, for which the puree was preliminarily centrifuged. The measurements were carried out at temperatures of 25 and 35 °С. It was found that, under equal conditions of centrifugation of puree, the proportion of supernatant in pear puree is noticeably higher – 77.37 % to the weight of puree in comparison with cherry plum puree (67.20 %) and apple puree (52.75 %). This fact can be explained by the presence of stony cells in the former which form an incompressible sediment, which allows a greater separation of the dispersed phase (sediment) and the dispersion medium (supernatant). It was found that the coefficient of surface tension of fruit purees, despite the slight difference, decreases with increasing temperature. Analysis of the steepness of the slope of the curve characterizing the effect of temperature on the surface tension coefficient showed that temperature stabilization during technological processing is more required for pear puree.

Some Properties of Probiotic Yoghurt Produced for Babies by Adding Fruit Puree, Containing B. infantis, B. bifidum, B. longum, L. paracasei

Probiotic yoghurt with fruit was produced to enrich the intestinal flora of infants and to prevent various ailments in infants when the flora is inadequate. Peach, apple and pear purees (10% and 20% each), cow milk, milk powder, starter culture (combination of Streptococcus thermophilus, Lactobacillus delbrueckii ssp. bulgaricus, Bifidobacterium infantis, Bifidobacterium bifidum, Bifidobacterium longum and Lactobacillus paracasei) were used in the production of probiotic yogurt for babies. Some properties of yoghurt samples were investigated during fermentation and on the 1st, 7th, 14th and 21st days of storage. After ten hours of fermentation, the lowest pH was observed in samples with apple puree. It has been determined that syneresis increases with increasing concentrations of fruit purees. The water holding capacity was less in yoghurts containing fruit puree compared to control yoghurt and in 20% fruit puree compared to yoghurts containing 10% fruit puree. The number of L. bulgaricus generally increased in all samples during storage. It was determined that the number of S. thermophilus in control sample was higher than other samples during storage. The number of L. paracasei and Bifidobacterium spp. decreased during storage. While the control sample remained probiotic until the 14th day of storage, other samples lost its probiotic properties before the 7th day of storage. Considering that the number of probiotic microorganisms in a probiotic product should be at least 106-107 CFU/g according to FAO, it has been decided that the most suitable fruits for probiotic yogurt with fruit puree are peach and apple, respectively. Considering the structural features, it is more appropriate to use 10% fruit puree, and considering the probiotic feature, it is more appropriate to use 20% fruit puree. Choosing the appropriate packaging and fixing suitable storage conditions will help probiotic microorganisms to preserve their vitality for a long time.

Разработка термостабильной начинки для булочных изделий на основе пюре из сибирской груши

The paper presents the results of a study on the development of a recipe for a thermal stability bakery filling from small-fruited Siberian pears. In the study, 5 variants of fillings formulations were worked out, slightly differing in their composition and the ratio of components. The composition of the fillings included such components as pear puree, milk powder, powdered sugar, butter, chopped cashew nuts, pectin, agar, starch.

Effects of fructose and stevia on the rheological, technological and sensory characteristics of ice cream

This study investigated the potential use of fructose and stevia to improve the technological parameters of ice cream. Ice cream was made of 2 different mixtures. Low-fat ice cream mixtures (0.4% fat) were made with: sweet buttermilk, 5% fructose, 20% banana puree, and sweet buttermilk, 5% fructose, 20% pear puree. The ice cream with stevia was made with cream (13% fat), milk, skim milk powder and whey powder, cherry puree (16%) and 0.48% stevia solution (20% concentration). The ice cream with banana showed rapid melting rate and the highest acidity. On the contrary, the ice cream with pear showed lower melting rate, but caused to increase the hardness and resulted with less overall acceptability. The enrichment of the ice cream with stevia and cherry showed the same coherence of hardness and overall acceptability.

Differential inhibitory effects of organic acids on pear polyphenol oxidase in model systems and pear puree

The inhibitory effects of ascorbic, citric, ferulic and salicylic acid on pear polyphenol oxidase (PPO) were investigated in model and food system. All four organic acids showed strong inhibition effect in model system. However, compared to model system, inhibitory effect of PPO in pear puree was quite different. Ascorbic acid showed a much weaker effect in pear puree compared to the model system. Similarly, ferulic and salicylic acid had limited inhibitory effect in pear puree. Interestingly, the inhibition of PPO activity was not correlated to browning control in pear puree. Ascorbic acid in low concentration was not effective in inhibiting PPO activity in pear puree but exhibited an excellent anti-browning effect. The study indicates that the level of PPO activity is not always a good indicator of susceptibility to browning in foods. Overall, ascorbic acid showed the strongest inhibition of browning and increased the total phenolic content of pear puree.

The use of pear fillers in kefir technology

The article substantiates the possibility of using pears and cinnamon in technology of kefir that was manufactured by a thermostatic method. Natural sources of plant material are selected. It was selected a pear containing sugar, organic acids, enzymes, cellulose , tannins, nitrogen and pectin substances, vitamins C, B1, P, PP, carotene (provitamin A), flavonoids, phytoncides and cinnamon containing essential oils, tannins, resins, minerals and dietary fiber. The technology of preparation of pear fillers, namely, pear puree and pear jam, has been developed. The recipe for kefir with fillers is calculated. The expediency of using the certain ingredients of a beverage is substantiated. For fermentation of the normalized mixture, ferment Kefir 12 was used by Chr. Hansen company. The composition of this ferment includes Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactococcus lactis subsp. lactis biovar diacetylactis, Leuconostoc mesenteroides, Bifidobacterium infantis, Bifidobacterium lactis, Lactobacillus fermentum, Lactobacillus lactis, Lactobacillus paracasei, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. lactis. The optimum dose of ferment, which is 0.2–0.4% of the normalized mixture, is determined. Kefir was manufactured by thermostatic method. The normalized milk mixture with fillers was fermentated at a temperature of 27 to 29 °C for 5–6 hours. The mass fraction of fat in the finished product was 2.5%. The study of the change of active and titrated acidity during the fermentation of the product, as well as storage at the 7th and 10th days was conducted. The storage period of the resulting beverage, which is not less than seven days at a temperature of 4 ± 2 °С, is determined. The organoleptic and physico-chemical parameters of the finished product are described. Investigated physico-chemical and organoleptic parameters of kefir samples meet the requirements of DSTU 4417:2005 “Kefir. Specifications”. The use of pears and cinnamon in kefir production is expedient because of the product's enrichment with biologically active substances and the expansion of the assortment of dairy products.

The Inactivation Kinetics of Soluble and Membrane-Bound Polyphenol Oxidase in Pear during Thermal and High-Pressure Processing

Polyphenol oxidase (PPO) from pear was characterized with catechol as substrate. The Michaelis constant of soluble and membrane-bound PPO were 15.6 and 23.8 mM, respectively, and their optimum pH for activity were 6.0 and 6.5, respectively. The inactivation kinetics of soluble and membrane-bound PPO during thermal (45–75 °C) and high-pressure thermal processing (600 MPa, 40–80 °C) were studied. The inactivation kinetics of pear PPO were described by a first-order model at all processing conditions. Compared to soluble PPO, membrane-bound PPO was more sensitive to thermal and high-pressure inactivation. Both soluble and membrane-bound PPO displayed higher sensitivity towards thermal inactivation at pH 3.5 (pH of pear puree made from pears dipped in citric acid prior to blending) compared to pH 4.4 (pH of non-acidified pear puree). High pressure and temperature had synergistic inactivation effects on pear PPO at pH 4.4 while slight antagonistic effects were observed at pH 3.5.

Effect of citric acid and high pressure thermal processing on enzyme activity and related quality attributes of pear puree

Abstract Pear puree was acidified with citric acid and was subjected to thermal (TP) and high pressure-thermal processing (HPTP). Citric acid inhibited peroxidase (POD) and polyphenol oxidase (PPO) and preserved the color of pear puree. The addition of citric acid (2%, w/w) increased total phenolic content (TPC) and oxygen radical absorbance capacity (ORAC) of pear puree by ~ 50%. POD was more sensitive than PPO to thermal and HPT inactivation. Citric acid enhanced thermal and HPT inactivation and complete inactivation of POD was observed after TP (90 °C, 7 min) and HPTP (600 MPa, 90 °C, 5 min) in acidified samples, while a maximum 60% inactivation of PPO was observed under these conditions. TP resulted in a slightly better color retention of acidified samples than HPTP under conditions of equivalent enzyme inactivation, whereas TPC and ORAC remained stable irrespective of the process. Industrial relevance This study investigated the effect of thermal and high pressure thermal processing with and without citric acid on the activity of oxidative enzymes and related quality attributes of pear puree. Citric acid inhibited enzymatic browning, protected polyphenolic antioxidants against oxidative degradation and resulted in 50% increase in antioxidant capacity when it was added at 2% (w/w). Acidified pear puree can possibly be used as an ingredient in products such as yoghurts, jams and baby food after either thermal or high pressure thermal processing due to its reduced oxidative enzyme activity, low pH, high antioxidant capacity and excellent color retention.

CFD Simulation for the Pasteurization of Fruit Puree with Pieces

Thermal pasteurization is a technique widely utilized in the industry to reduce the microbial content of foods and increase their shelf life. The food pasteurization is commonly carried out in continuous process where the food undergoes to a rapid heating and a subsequent cooling with high heat transfer coefficients in order to reduce the degradation of main constituents like proteins and vitamins, and keeping almost unchanged the food organoleptic properties. Continuous pasteurization processes are commonly used to treat creams, tomato sauce, fruit juice, as well as products with solid particles or pieces like soups or baby foods. In such cases, the presence of dispersed large particles in the fluid can causes issues in the correct process setup. Indeed, the process setup must assure the pasteurization condition in the overall product food, included the centre of the particles. Here the heat penetrates by conduction and usually it becomes the actual limiting step of the process. In this work we estimate the pasteurization condition for a pilot scale pasteurization process for the thermal treatment of pear puree with pieces by the use of the Computational Fluid Dynamic approach. The results show that the heat penetration resistance into the solid particle reduces of about 32% the microbial abatement in the particle centre; however the P85 value results always higher than the minimum required for the food pasteurization.

Survival of Arcobacter butzleri in Apple and Pear Purees

AbstractThis study examined the survival of Arcobacter butzleri in apple and pear purees. The apple and pear purees were prepared by following a previous study and these were spiked with 6.90–7.44 log10 cfu/g of A. butzleri ATCC49616, A. butzleri CAU076046 and A. butzleri CAU080180, respectively. The number of bacteria, pH value, sugar contents and water activity of apple and pear purees stored at 4 and 20C for 48 h were measured. The population of all strains significantly decreased in apple and pear purees at 8, 12, 24 and 48 h (P < 0.01). Each A. butzleri strain was reduced by 7 log10 cfu/g after 24–48 h in apple or pear purees at 4C. A. butzleri strain CAU080180 was not detected within 12 h and the others were not detected at 20C within 24–48 h. A. butzleri CAU076046 was more resistant in the purees than the other two strains. No significant difference in the pH values, sugar content or water activity was observed between 0 and 48 h. We demonstrated that the number of A. butzleri significantly decreased in apple and pear purees.Practical ApplicationsArcobacter butzleri causes gastroenteritis in children, elderly and immunocompromised patients. The contamination of A. butzleri occurred not only in meats but also in vegetable or fruits. This study demonstrated that A. butzleri was reduced in the apple or pear purees during storage. The combination of pH, organic acids and flavonoids synergistically inhibit the survival of A. butzleri in purees.

Defining the environmental and functional characteristics of the buildings used to produce prickly pear dried puree in terms of food hygiene and safety

Sun-dried prickly pear puree, ‘mostarda’, is a traditional food mostly produced in Eastern Sicily (Italy) by cooking and concentrating fruit juice.The artisan production process takes place in buildings not designed for maintaining hygiene. It is well-known that the right organisation and building quality in food production influences food safety, allowing greater control over any infestation and simplifying cleaning.So, by means of building meta-design which analyses the production requirements of the main producers of prickly pear puree, production areas which provide appropriate levels of hygiene have been meta-designed without essentially modifying the traditional process.The meta-design approach was able to identify the necessary production areas and their respective functional and environmental requisites as well as their reciprocal links. The main results are a series of design reference layouts aimed at simplifying production activities by implementing the necessary functional organisation both as regards single sections as well as the entire production process such that HACCP can be optimised.

김치에서 신규 Leuconostoc mesenteroides KACC 91495P 균주의 분리 및 이를 이용한 배 발효물의 제조

김치에서로부터 배 파쇄물에서 생육과 산 생성이 우수한 유산균을 선발하였다. 선발된 균주는 Ln. mesenteroides로 동정되었으며, 국립농업과학원 농업유전자원센터에 KACC 91495P로 기탁하였다. KACC 91495P 균주를 배 파쇄물에 접종한 후 pH, 적정산도, 생균수의 변화를 경시적으로 분석하였다. 배양액의 pH는 배양 9시간 이후 pH 4.05로 급격히 감소한 후 배양 18시간에 pH 3.86까지 완만하게 감소하였다. 적정산도는 배양 초기부터 15시간까지 지속적으로 증가하여 1.09% 수준에서 평형을 이루었다. 생균수는 접종 후 9시간까지 급격히 증가하고 그 이후 완만하게 증가하여 배양 18시간에는 <TEX>$2.9{\times}10^9\;CFU/g$</TEX>까지 증가하였다. 유기산 농도는 배양시간에 비례하여 증가하여 18시간 배양 후 젖산이 0.213%, 초산이 0.259%, 사과산이 0.217%로 분석되었다. 또한 배 발효액의 총 폴리페놀 함량은 9시간 배양 후 <TEX>$134\;{\mu}g$</TEX> tannic acid/mL에서 <TEX>$185\;{\mu}g$</TEX> tannic acid/mL로 약 40% 증가하였으며 따라서 DPPH radical 소거활성도 향상되었다. 또한 <TEX>$4^{\circ}C$</TEX>에서 KACC 91495P 균주에 의한 배 발효물은 약 2주일의 저장기간 동안 pH, 적정산도, 총균수의 변화는 미미하였다. A lactic acid bacterial strain showing fast growth and high acid production in Korean pear puree was isolated from Kimchi. This strain was analyzed by API 50 CHL kit and 16S rRNA sequencing analysis and identified as Leuconostoc (Ln.) mesenteroides KACC 91495P. Korean pear puree was fermented using Ln. mesenteroides KACC 91495P strain at <TEX>$30^{\circ}C$</TEX> for 18 h. The changes of pH, titratable acidity and viable cell number during fermentation were investigated. The pH and titratable acidity were reached to pH 3.86 and 1.09% after 18 h fermentation, respectively. The viable cell population of Ln. mesenteroides KACC 91495P was rapidly increased to <TEX>$2.0{\times}10^9\;CFU/g$</TEX> during the 9 h of cultivation. The contents of lactic acid, acetic acid and malic acid were determined to be 0.213, 0.259, and 0.217% after 18 h fermentation, respectively. The content of polyphenolic compounds, known as antioxidants, in pear puree were enhanced by Ln. mesenteroides KACC 91495P cultivation. The level of total polyphenolic compounds was increased to around 140% of initial concentration. When the fermented pear puree was kept at <TEX>$4^{\circ}C$</TEX>, pH, titratable acidity and number of viable cells population were nearly maintained for 13 days.

SENSORY EVALUATION OF THE TEXTURE OF 49 COMMERCIAL APPLE AND PEAR PUREES

ABSTRACT The sensory texture of 49 market samples of pear and apple purees were examined by Flash profile and results were treated by Generalized Procustes Analysis. The product set encompassed grocery products, baby foods and drinking snacks. Four main sensory notions were used to describe the texture of this type of products: graininess, viscosity, moisture and grittiness. Pear and apple purees were discriminated by the gritty perception, carried out on the third component. The other three main characteristics were carried out on the first two axes, where six main groups of products were identified. Pear purees were close to baby foods. Thickened baby foods and pear and apple mixtures constituted additional groups. Finally, apple purees were close sensorially, but three groups could be discriminated by grainy and viscous perceptions. The number of products was not an obstacle and the panel managed the task as required. PRACTICAL APPLICATIONSFlash profile seems to be a powerful tool to provide a statement of the sensory diversity of a specific market very quickly even when the number of products is quite large.

Aroma of dehydrated pear products

Pear purees and cubes were dehydrated with sugars (sucrose and trehalose) addition. Freeze drying and foam-mat drying were used. Manual solid-phase microextraction (SPME) coupled with gas chromatography (GC–flame ionization detector (FID) and GC–MS) was applied to determine the changes in retention of aroma compounds in dehydrated pear purees and cubes. The best retention of aroma compounds in dehydrated pear purees was noticed in the case when freeze drying and trehalose addition were combined. In dehydrated pear cubes, previously dipped in trehalose solution, the highest aroma retention was also determined. This study showed possible application of trehalose as potentially beneficial food ingredient, with the aim to improve the quality of dehydrated fruit products, especially their aroma, and to produce superior dried fruit products or ingredients, which are widely used in food formulation.

Analysis of phenolic compounds in the evaluation of commercial quince jam authenticity.

The phenolic compounds present in 17 samples of Portuguese commercial and three homemade quince jams were analyzed by reversed-phase HPLC/DAD, to determine their authenticity. Two different extraction methods were needed for the complete definition of quince jams profiles, one of them including an Amberlite XAD-2 cleaning step. These analyses showed that all the samples presented a similar profile composed of at least eight identified phenolic compounds, several unidentified characteristic procyanidin polymers, and sodium benzoate as preservative of quince jams. Several samples also contained arbutin, suggesting that these quince jam samples were fraudulently adulterated with pear puree.