scholarly journals Effect of the type of packaging on the oxidative stability of pine nuts (Pinus pinea L.) grown in Chile

2018 ◽  
Vol 16 (1) ◽  
pp. 255-262 ◽  
Author(s):  
Henríquez ◽  
Loewe ◽  
Saavedra ◽  
Córdova ◽  
Lutz

Pine nut (Pinus pinea L.) is a nutritious, expensive tree nut. During storage, it is exposed to a wide range of environmental deteriorative conditions. This study describes the oxidative stability of pine nuts kept in pouches made of three different packaging materials and stored at three different temperatures. The packaging materials evaluated were low-density polyethylene (LDP), high-density polyethylene (HDP), and high-barrier metallized film (MF). Temperatures evaluated were 4, 20, and 60°C. In addition, a control unpacked sample was also evaluated in identical conditions. The oxidative parameters evaluated were acid value and peroxide value. Data analyses include a shelf-life study and a principal component analysis. The results obtained indicate what the best packaging material at 20°C was MF with a shelf-life of 703 d. At 4°C, the shelf-life of pine nuts stored in HDP was 1148 d. It is concluded that it is fundamental to use an adequate packaging to protect the seeds from environmental conditions that promote deterioration.

2016 ◽  
Vol 12 (4) ◽  
pp. 385-393
Author(s):  
Naima Al-Kharousi ◽  
Mohammed Al-Khusaibi ◽  
Ismail Al-Bulushi ◽  
Nejib Guizani ◽  
Mostafa Waly ◽  
...  

Abstract In this study, oxidative stability of date-pits (i. e. Khalas variety) was investigated during storage as a function of temperature. The stability of date-pits oil was determined by measuring acid value (AV), peroxide value (PV), p-anisidine value (PAV), tocopherol and oxidative stability index. Initial characteristics of oil were assessed by measuring its physico-chemical and melting characteristics, fatty acids composition and aflatoxin. Storage of date-pits caused highest reduction in linoleic acid (C18:2, ω6) followed by oleic acid (C18:1, ω9). AV, PV and PAV of the fresh oil were 1.41 mg KOH/g oil, 3.30 meq/kg oil and 0.60, respectively. These values increased linearly at slower rate in the case of 30 °C storage, while sharp rise was observed after 40 days in cases of 100 and 150 °C storage (p < 0.05). The results of this study indicate that date pits oil had a good oxidative and thermal stability and could thus be used to develop value-added food ingredients.


2004 ◽  
Vol 67 (4) ◽  
pp. 833-848 ◽  
Author(s):  
ARZU CAGRI ◽  
ZEYNEP USTUNOL ◽  
ELLIOT T. RYSER

Increasing consumer demand for microbiologicallysafer foods, greater convenience,smaller packages, and longer product shelf life is forcing the industry to develop new food-processing,cooking, handling, and packaging strategies. Nonfluid ready-to-eat foods are frequently exposed to postprocess surface contamination, leading to a reduction in shelf life. The food industry has at its disposal a wide range of nonedible polypropylene- and polyethylene-based packaging materials and various biodegradable protein- and polysaccharide-based edible films that can potentially serve as packaging materials. Research on the use of edible films as packaging materials continues because of the potential for these films to enhance food quality, food safety, and product shelf life. Besides acting as a barrier against mass diffusion (moisture, gases, and volatiles), edible films can serve as carriers for a wide range of food additives, including flavoring agents, antioxidants, vitamins, and colorants. When antimicrobial agents such as benzoic acid, sorbic acid, propionic acid, lactic acid, nisin, and lysozyme have been incorporated into edible films, such films retarded surface growth of bacteria, yeasts, and molds on a wide range of products, including meats and cheeses. Various antimicrobial edible films have been developed to minimize growth of spoilage and pathogenic microorganisms, including Listeria monocytogenes, which may contaminate the surface of cooked ready-to-eat foods after processing. Here, we review the various types of protein-based (wheat gluten, collagen, corn zein, soy, casein, and whey protein), polysaccharide-based (cellulose, chitosan, alginate, starch, pectin, and dextrin), and lipid-based (waxes, acylglycerols, and fatty acids) edible films and a wide range of antimicrobial agents that have been or could potentially be incorporated into such films during manufacture to enhance the safety and shelf life of ready-to-eat foods.


2012 ◽  
Vol 7 (1) ◽  
pp. 8
Author(s):  
Endang Warsiki ◽  
M. Rizal Damanik

Torbangun leaves soup is one of the traditional diets commonly consumed by lactating mothers among the Batak society. The soup is believed to increase breast milk production and helps recovery process after the mother giving birth. Unfortunately, until now the soup is only served directly after cooking thereby limits its usefulness. Given the potential of the soup is quite important, the preservation of the cooked soup needs to be done so that the soup can be consumed at anytimeany time. This study aims to determine the shelf life of torbangun soup in a variety of packaging and at various storage temperatures. The soup is stored at three different temperatures (3-5oC, 10-12oC and 27-30oC) and in 3 types of packaging namely polyethylene terephthalate (PET), polypropylene (PP) and cans. Changes in product quality during storage are analyzed and estimated the shelf life of products. The results show that the soup stored at the 3-5oC and 10-12oC has longer shelf life compared to 27-30oC (day 8 vs day 3). In addition, the cans are the best packing among other packaging materials.<br />Key words: torbangun leaf, Coleus amboinicus Lour, soup, shelf life<br />ABSTRAK<br />Sup daun Torbangun torbangun adalah salah satu makanan tradisional yang biasa dikonsumsi oleh ibu menyusui<br />di kalangan masyarakat Batak. Sup ini diyakini dapat meningkatkan produksi ASI dan membantu proses pemulihan setelah ibu melahirkan. Sayangnya, sampai saat ini sup daun torbangun hanya disajikan langsung setelah dimasak sehingga membatasi kegunaannya. Mengingat potensi sup ini cukup penting, penggunaan bahan pengawet pada sup matang perlu dilakukan agar sup ini dapat dikonsumsi kapan saja. Penelitian ini bertujuan untuk menentukan umur simpan sup torbangun dalam berbagai kemasan dan pada berbagai suhu penyimpanan. Pada penelitian ini sup disimpan pada tiga suhu berbeda (3-5oC, 10-12oC dan 27-30oC) dan di simpan dalam tiga jenis kemasan yaitu polietilen tereftalat (PET), polypropylene (PP) dan kaleng. Perubahan kualitas produk selama penyimpanan dianalisis dan dilakukan perkiraan umur simpan produk. Hasil penelitian menunjukkan bahwa sup yang disimpan pada suhu 3-5oC dan 10-12oC memiliki umur simpan lebih lama diban- dingkan dengan sup yang disimpan pada suhu 27-30oC (8 hari vs 3 hari). Selain itu kaleng adalah kemasan terbaik di antara bahan kemasan lainnya.


2020 ◽  
Author(s):  
Luis Anunciacao ◽  
janet squires ◽  
J. Landeira-Fernandez

One of the main activities in psychometrics is to analyze the internal structure of a test. Multivariate statistical methods, including Exploratory Factor analysis (EFA) and Principal Component Analysis (PCA) are frequently used to do this, but the growth of Network Analysis (NA) places this method as a promising candidate. The results obtained by these methods are of valuable interest, as they not only produce evidence to explore if the test is measuring its intended construct, but also to deal with the substantive theory that motivated the test development. However, these different statistical methods come up with different answers, providing the basis for different analytical and theoretical strategies when one needs to choose a solution. In this study, we took advantage of a large volume of published data (n = 22,331) obtained by the Ages and Stages Questionnaire Social-Emotional (ASQ:SE), and formed a subset of 500 children to present and discuss alternative psychometric solutions to its internal structure, and also to its subjacent theory. The analyses were based on a polychoric matrix, the number of factors to retain followed several well-known rules of thumb, and a wide range of exploratory methods was fitted to the data, including EFA, PCA, and NA. The statistical outcomes were divergent, varying from 1 to 6 domains, allowing a flexible interpretation of the results. We argue that the use of statistical methods in the absence of a well-grounded psychological theory has limited applications, despite its appeal. All data and codes are available at https://osf.io/z6gwv/.


2019 ◽  
Author(s):  
Bart Verkuil ◽  
Briana Brownlow ◽  
Michael Vasey ◽  
Jos F. Brosschot ◽  
Julian F. Thayer

Worry is a central process in a wide range of psychopathological and somatic conditions. Three studies (N = 856) were used to test whether a subscale composed of five items of the most commonly used trait anxiety questionnaire, Spielberger’s State Trait Anxiety Inventory-Trait version (STAI-T), is appropriate to measure worry. Results showed that the subscale, named the Brief Worry Scale (BWS), had excellent internal consistency and temporal stability. Convergent and divergent validity were supported by correlation analyses using worry questionnaires and measures of anxious arousal and depression. The BWS was a particularly good predictor of the pathogenic aspects of worry, including worry perseveration in daily life (study 1), measures of clinical worry (study 2) and the uncontrollability of experimentally induced worry (study 3). Taken together, these studies demonstrate that the BWS might be a valuable scale for pathological worry, for which many researchers already have data.


Author(s):  
Emma M. Björk ◽  
Aylin Atakan ◽  
Pei-Hsuan Wu ◽  
Alessandra Bari ◽  
Carlotta Pontremoli ◽  
...  

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 680
Author(s):  
Thuy T. P. Mai ◽  
Craig M. Hardner ◽  
Mobashwer M. Alam ◽  
Robert J. Henry ◽  
Bruce L. Topp

Macadamia is a recently domesticated Australian native nut crop, and a large proportion of its wild germplasm is unexploited. Aiming to explore the existing diversity, 247 wild accessions from four species and inter-specific hybrids were phenotyped. A wide range of variation was found in growth and nut traits. Broad-sense heritability of traits were moderate (0.43–0.64), which suggested that both genetic and environmental factors are equally important for the variability of the traits. Correlations among the growth traits were significantly positive (0.49–0.76). There were significant positive correlations among the nut traits except for kernel recovery. The association between kernel recovery and shell thickness was highly significant and negative. Principal component analysis of the traits separated representative species groups. Accessions from Macadamia integrifolia Maiden and Betche, M. tetraphylla L.A.S. Johnson, and admixtures were clustered into one group and those of M. ternifolia F. Muell were separated into another group. In both M. integrifolia and M. tetraphylla groups, variation within site was greater than across sites, which suggested that the conservation strategies should concentrate on increased sampling within sites to capture wide genetic diversity. This study provides a background on the utilisation of wild germplasm as a genetic resource to be used in breeding programs and the direction for gene pool conservation.


Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 300
Author(s):  
Jhih-Ying Ciou ◽  
Hsin-Chun Chen ◽  
Chih-Wei Chen ◽  
Kai-Min Yang

The study sought to investigate the effect of roasting temperatures on antioxidant components and oxidative stability of peanut oils. The total phenolic content, total flavonoid content, α–tocopherol content, and phytosterol content in peanut oils was influenced by roasting at temperatures of 120 °C, 140 °C, and 160 °C, while those roasting temperatures had no effect on the fatty acid profile and γ–tocopherol content of peanut oils. Roasting promotes the quality of peanut oil aroma via the Maillard reaction, particularly when it is derived from N–heterocyclic compounds (such as pyrazine and pyrrole). The oxidative stability of peanut oils was investigated using the Rancimat method, and the results show that there is a linear relationship between roasting and natural logarithm of the induction period (R2: 0.959~0.998). This was determined based on the Arrhenius equation, which indicated the activation energy (Ea) was in the range of 82.08~108.61 kJ/mol. In principal component analysis (PCA) analysis, the antioxidant stability of the increase levels of phenols released in the peanut oils was found to rise with the increment of roasting temperatures. The data obtained in this study should be confirmed as the nutritional benefits of peanut oils that will be most appealing to consumers.


Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 287
Author(s):  
Donny W. H. Merkx ◽  
Andries Swager ◽  
Ewoud J. J. van Velzen ◽  
John P. M. van Duynhoven ◽  
Marie Hennebelle

Food emulsions with high amounts of unsaturated fats, such as mayonnaise, are prone to lipid oxidation. In the food industry, typically accelerated shelf life tests are applied to assess the oxidative stability of different formulations. Here, the appearance of aldehydes at the so-called onset time, typically weeks, is considered a measure for oxidative stability of food emulsions, such as mayonnaise. To enable earlier assessment of compromised shelf-life, a predictive model for volatile off-flavor generation is developed. The model is based on the formation kinetics of hydroperoxides, which are early oxidation products and precursors of volatile aldehydes, responsible for off-flavor. Under accelerated shelf-life conditions (50 °C), hydroperoxide (LOOH) concentration over time shows a sigmoidal curvature followed by an acceleration phase that occurs at a LOOH-concentration between 38–50 mmol/kg, here interpreted as a critical LOOH concentration (CCLOOH). We hypothesize that the time at which CCLOOH was reached is related to the onset of aldehyde generation and that the characterization of the LOOH-generation curvature could be based on reaction kinetics in the first days. These hypotheses are tested using semi-empirical models to describe the autocatalytic character of hydroperoxide formation in combination with the CCLOOH. The Foubert function is selected as best describing the LOOH-curvature and is hence used to accurately predict onset of aldehyde generation, in most cases within several days of shelf-life. Furthermore, we find that the defining parameters of this model could be used to recognize antioxidant mechanisms at play.


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