Učinak hidrolizata glutena i njegovih frakcija dobivenih ultrafiltracijom na svojstva tijesta i kakvoću kruha

Two fractions (50-K and permeate) from a proteolytic hydrolysate (degree of hydrolysis, DH=3.8 %) of wheat gluten were separated using ultrafiltration (UF) membrane with molecular mass cut-off of 50 kDa. The effects of the wheat gluten hydrolysate (WGH) and its UF fractions on the mixing behaviour and viscoelastic properties of wheat dough were presented. The WGH and its UF fractions modified the mixing properties of dough. The addition of these fractions improved the viscoelastic characteristics of wheat dough. A significant (p<0.05) effect of 50-K fraction on these characteristics of wheat dough was observed. After adding these fractions, the bread was considered acceptable by the sensory panel. Also, 50-K fraction resulted in significant (p<0.05) increase in the crumb firmness, while the bread made with wheat flour with WGH and permeate (P) fraction showed softer crumbs compared to that of wheat flour. Moreover, these fractions had anti-staling properties for bread during storage. Hence, the wheat gluten hydrolysate and its UF fractions are the products with promising potential in the baking products.Odvojene su dvije frakcije (50-K i permeat) iz proteolitičkog hidrolizata glutena (stupanj hidrolize, DH=3,8 %) pomoću ultrafiltracijske (UF) membrane sa segmentima molarne mase od 50 kDa. Prikazan je učinak hidrolizata glutena i njegovih frakcija dobivenih ultrafiltracijom na dizanje tijesta i njegovu viskoznost i elastičnost tijekom miješanja. Utvrđeno je da se dodatkom hidrolizata glutena i njegovih frakcija mijenjaju svojstva tijesta pri miješanju, te poboljšavaju viskoznost i elastičnost tijesta. Uočen je značajan učinak (p<0,05) dodatka frakcije 50-K na ta svojstva tijesta, te znatno (p<0,05) povećanje čvrstoće mrvica, a takav je kruh imao zadovoljavajuće karakteristike, što je potvrdila i ocjenjivačka komisija. Kruh od pšeničnog brašna s dodatkom hidrolizata glutena i frakcije permeata dao je mekše mrvice od kruha napravljenog samo od pšeničnog brašna. Osim toga, dodatak tih frakcija spriječio je stvaranje plijesni na kruhu tijekom skladištenja. Stoga hidrolizat glutena i njegove frakcije dobivene ultrafiltracijom imaju velike mogućnosti primjene u pekarskim proizvodima

Phytochemical analyses of Ziziphus jujuba Mill. var. spinosa seed by ultrahigh performance liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry

Analyst138226881-688

Effects of Hot Water Immersion on Storage Quality of Fresh Broccoli Heads

Freshly harvested broccoli heads were immersed for 0, 1, 4 or 8 min into hot water at 45 °C, and then were hydrocooled rapidly for 10 min at 10 °C. Following these treatments, the broccoli were air-dried for 30 min, then packed in commercial polymeric film bags, and, finally, stored for 16 days at –1, 1, and 12 °C. The samples treated with hot water maintained high contents of chlorophyll concentrations, their yellowing rate was delayed, and fungal infection and chilling or freezing injury were inhibited markedly. Compared to non-heat-treated broccoli, a lower level of peroxidase activity with a relatively higher chlorophyll concentration was observed when broccoli were treated with hot water. Among these heat treatments, immersion in hot water for 4 min at 45 °C was the most effective for maintaining the quality of harvested broccoli heads

Anoxia Treatment for Delaying Skin Browning, Inhibiting Disease Development and Maintaining the Quality of Litchi Fruit

Litchi fruit has a very short shelf life after harvest, so marketers and consumers alike desire longer periods of storage, transportation and distribution. To extend shelf life, anoxia treatments were used for the fruit. Litchi fruit were exposed to pure N2 for 0, 3, 6, 12 or 24 h. They were then kept individually in closed but vented containers for 6 days in the dark at 20 °C and 95–100 % relative humidity. Exposure of litchi fruit to N2 for 3 or 6 h markedly delayed skin browning, reduced rot development and maintained higher concentrations of total soluble solids, titratable acidity and ascorbic acid after 6 days of storage. Anoxia treatment for 24 h reduced browning index, but it accelerated disease development, compared to the control. Thus, a pre-storage pure N2 treatment for 3 or 6 h can be an effective means of reducing rotting while maintaining the physical quality of the fruit

Enhanced DPPH radical scavenging activity and DNA protection effect of litchi pericarp extract by Aspergillus awamori bioconversion

BACKGROUND: Litchi (Litchi chinensis Sonn.) pericarp is a major byproduct which contains a significant amount of polyphenol. This study was designed to biotransformation litchi pericarp extract (LPE) by Aspergillus awamori to produce more bioactive compounds with stronger antioxidant activities. RESULTS: The study exhibited that the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activities significantly (p < 0.05) increased from 15.53% to 18.23% in the water-extracted fraction and from 25.41% to 36.82% in the ethyl acetate-extracted fraction. Application of DNA cleavage assay further demonstrated the enhanced protection effect of the fermented phenolics on DNA damage. It is also noted that the water-extracted fraction of the fermented LPE possessed a much stronger capacity than the ethyl acetate-extracted fraction to prevent from damage of supercoiled DNA. Interestingly, it was found that some new compounds such as catechin and quercetin appeared after of A. awamori fermentation of LPE, which could account for the enhanced antioxidant activity. CONCLUSION: The DPPH radical scavenging activity and DNA protection effect of LPE were increased by Aspergillus awamori bioconversion while some compounds responsible for the enhanced antioxidant activity were identified. This study provided an effective way of utilizing fruit pericarp as a readily accessible source of the natural antioxidants in food industry and, thus, extended the application area such as fruit by-products

Effects of 1-Methylcyclopropene Treatments on Ripening and Quality of Harvested Sapodilla Fruit

Ubrani plodovi šljive sapodilo izloženi su inhibitoru djelovanja etena 1- metilciklopropenu (1-MCP), volumne koncentracije od 0, 40 ili 80 nL/L, tijekom 24 h pri 20 °C. Voće je zatim skladišteno na 20 °C i 85-95 % relativne vlažnosti, pa su zatim procijenjeni njegova kakvoća i karakteristike zrenja. Obrada 1-metilcikloproprenom odgodila je maksimalnu respiraciju, proizvodnju etena i poligalakturonaze za 6 dana. Također je odgodila smanjenje koncentracije vitamina C, titracijske kiselosti i udjela klorofila do kojeg dolazi zrenjem voća. U usporedbi s netretiranim voćem usporena je i promjena udjela čvrste tvari. Primjena 1-metilciklopropena djelotvorna je tehnologija inhibicije zrenja i očuvanja kakvoće ubrane šljive sapodilo.Sapodilla fruits were exposed to the ethylene action inhibitor 1-methylcyclopropene (1-MCP) at 0, 40 or 80 nL/L for 24 h at 20 °C. Fruits were then stored at 20 °C and 85−95 % relative humidity and later assessed for quality and ripening characteristics. 1-MCP treatments delayed the increases in the rates of respiration and ethylene production by 6 days. Treatments also delayed by 6 days the increase in polygalacturonase activity. Decreases in ascorbic acid, titratable acidity and chlorophyll content that are normally seen with ripening were delayed. Changes in the content of soluble solids were also slowed compared to untreated fruit. The application of 1-MCP was an effective technology for ripening inhibition and quality maintenance of harvested sapodilla fruit

A Simple and Rapid Determination of ATP, ADP and AMP Concentrations in Pericarp Tissue of Litchi Fruit by High Performance Liquid Chromatography

Razvijena je jednostavna i brza metoda određivanja masenog udjela adenozin trifosfata (ATP), adenozin difosfata (ADP) i adenozin monofosfata (AMP) visokodjelotvornom tekućinskom kromatografijom (HPLC) u perikarpu voća liči. Pri određivanju adenozin fosfata upotrijebljen je acetonitril koji skraćuje vrijeme postupka. Također je postignuta dobra ponovljivost (koeficijent varijacije iznosi 1,28-1,80 %) i obnovljivost (94,7-97,1 %). Koeficijenti korelacije s površinama pika u rasponu od 0 do 80 ng iznosili su 0,9946 za ATP; 0,9994 za ADP i 0,9974 za AMP. Ova je metoda primijenjena za određivanje masenog udjela adenozin fosfata u perikarpu voća liči pri berbi, pa je utvrđeno da je maseni udio ATP-a iznosio 27,4 μg/g, ADP-a 35,4 μg/g i AMP-a 7,9 μg/g, na bazi svježe tvari voća.A simple and rapid method using high performance liquid chromatography (HPLC) was developed to determine levels of adenosine triphosphate (ATP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP) in litchi fruit pericarp tissue. This HPLC method used acetonitrile gradient elution and shortened the time required for determinations of adenosine phosphates. This analysis exhibited good repeatability (coefficients of variation 1.28–1.80 %) and recovery rate (94.7–97.1 %). The correlation coefficients of ATP, ADP and AMP with their peak areas at a range of 0–80 ng were 0.9946, 0.9994 and 0.9974, respectively. This method was applied to determine levels of adenosine phosphates in pericarp tissue of litchi fruit at harvest. There were 27.4 μg/g of ATP, 35.4 μg/g of ADP and 7.9 μg/g of AMP on a fresh mass basis

Učinak hidrolizata glutena i njegovih frakcija dobivenih ultrafiltracijom na svojstva tijesta i kakvoću kruha

Two fractions (50-K and permeate) from a proteolytic hydrolysate (degree of hydrolysis, DH=3.8 %) of wheat gluten were separated using ultrafiltration (UF) membrane with molecular mass cut-off of 50 kDa. The effects of the wheat gluten hydrolysate (WGH) and its UF fractions on the mixing behaviour and viscoelastic properties of wheat dough were presented. The WGH and its UF fractions modified the mixing properties of dough. The addition of these fractions improved the viscoelastic characteristics of wheat dough. A significant (p<0.05) effect of 50-K fraction on these characteristics of wheat dough was observed. After adding these fractions, the bread was considered acceptable by the sensory panel. Also, 50-K fraction resulted in significant (p<0.05) increase in the crumb firmness, while the bread made with wheat flour with WGH and permeate (P) fraction showed softer crumbs compared to that of wheat flour. Moreover, these fractions had anti-staling properties for bread during storage. Hence, the wheat gluten hydrolysate and its UF fractions are the products with promising potential in the baking products.Odvojene su dvije frakcije (50-K i permeat) iz proteolitičkog hidrolizata glutena (stupanj hidrolize, DH=3,8 %) pomoću ultrafiltracijske (UF) membrane sa segmentima molarne mase od 50 kDa. Prikazan je učinak hidrolizata glutena i njegovih frakcija dobivenih ultrafiltracijom na dizanje tijesta i njegovu viskoznost i elastičnost tijekom miješanja. Utvrđeno je da se dodatkom hidrolizata glutena i njegovih frakcija mijenjaju svojstva tijesta pri miješanju, te poboljšavaju viskoznost i elastičnost tijesta. Uočen je značajan učinak (p<0,05) dodatka frakcije 50-K na ta svojstva tijesta, te znatno (p<0,05) povećanje čvrstoće mrvica, a takav je kruh imao zadovoljavajuće karakteristike, što je potvrdila i ocjenjivačka komisija. Kruh od pšeničnog brašna s dodatkom hidrolizata glutena i frakcije permeata dao je mekše mrvice od kruha napravljenog samo od pšeničnog brašna. Osim toga, dodatak tih frakcija spriječio je stvaranje plijesni na kruhu tijekom skladištenja. Stoga hidrolizat glutena i njegove frakcije dobivene ultrafiltracijom imaju velike mogućnosti primjene u pekarskim proizvodima

DeltaSpace: A Semantic-aligned Feature Space for Flexible Text-guided Image Editing

Text-guided image editing faces significant challenges to training and inference flexibility. Much literature collects large amounts of annotated image-text pairs to train text-conditioned generative models from scratch, which is expensive and not efficient. After that, some approaches that leverage pre-trained vision-language models are put forward to avoid data collection, but they are also limited by either per text-prompt optimization or inference-time hyper-parameters tuning. To address these issues, we investigate and identify a specific space, referred to as CLIP DeltaSpace, where the CLIP visual feature difference of two images is semantically aligned with the CLIP textual feature difference of their corresponding text descriptions. Based on DeltaSpace, we propose a novel framework called DeltaEdit, which maps the CLIP visual feature differences to the latent space directions of a generative model during the training phase, and predicts the latent space directions from the CLIP textual feature differences during the inference phase. And this design endows DeltaEdit with two advantages: (1) text-free training; (2) generalization to various text prompts for zero-shot inference. Extensive experiments validate the effectiveness and versatility of DeltaEdit with different generative models, including both the GAN model and the diffusion model, in achieving flexible text-guided image editing. Code is available at https://github.com/Yueming6568/DeltaEdit.Comment: 17 pages. arXiv admin note: text overlap with arXiv:2303.0628

Effects of 1-Methylcyclopropene Treatments on Ripening and Quality of Harvested Sapodilla Fruit

Ubrani plodovi šljive sapodilo izloženi su inhibitoru djelovanja etena 1- metilciklopropenu (1-MCP), volumne koncentracije od 0, 40 ili 80 nL/L, tijekom 24 h pri 20 °C. Voće je zatim skladišteno na 20 °C i 85-95 % relativne vlažnosti, pa su zatim procijenjeni njegova kakvoća i karakteristike zrenja. Obrada 1-metilcikloproprenom odgodila je maksimalnu respiraciju, proizvodnju etena i poligalakturonaze za 6 dana. Također je odgodila smanjenje koncentracije vitamina C, titracijske kiselosti i udjela klorofila do kojeg dolazi zrenjem voća. U usporedbi s netretiranim voćem usporena je i promjena udjela čvrste tvari. Primjena 1-metilciklopropena djelotvorna je tehnologija inhibicije zrenja i očuvanja kakvoće ubrane šljive sapodilo.Sapodilla fruits were exposed to the ethylene action inhibitor 1-methylcyclopropene (1-MCP) at 0, 40 or 80 nL/L for 24 h at 20 °C. Fruits were then stored at 20 °C and 85−95 % relative humidity and later assessed for quality and ripening characteristics. 1-MCP treatments delayed the increases in the rates of respiration and ethylene production by 6 days. Treatments also delayed by 6 days the increase in polygalacturonase activity. Decreases in ascorbic acid, titratable acidity and chlorophyll content that are normally seen with ripening were delayed. Changes in the content of soluble solids were also slowed compared to untreated fruit. The application of 1-MCP was an effective technology for ripening inhibition and quality maintenance of harvested sapodilla fruit