Bitter Scores Research Articles

Quantitive Assessment of Gustatory Function and Its Association with Demographics, and Systemic Morbidity.

This study aimed to analyze the associations of gustatory dysfunction as measured by validated taste strips with demographics and co-morbidities. This cross-sectional study retrospectively analyzed records of patients who attended the Orofacial Chemosensory Center of Hadassah Medical Center between 2017 and 2020. Taste strips were used as a validated method to determine taste dysfunction. A total of 272 subjects were included, 137 (50.4%) women and 135 (49.6%) men, with a mean age of 53.5 ± 19.3 years and age range of 18-98 years. The total taste score among the study population was 8.53 ± 4.03 (scale range 0-16). Age had a significant negative correlation with the total taste score (p = 0.001), and men exhibited worse total (p < 0.001), salty (p = 0.003), and bitter (p < 0.001) scores. Major trauma was associated with worse total (p < 0.001) and specialized taste assessments (sweet (p = 0.001), sour (p = 0.002), salty (p = 0.016), and bitter (p < 0.001)). Chemotherapy was associated with reduced total (p < 0.001), salty (p = 0.003), and bitter (p = 0.001) taste scores. Zinc deficiency exhibited worse salty (p = 0.027) and total (p = 0.038) taste scores. Patients with burning mouth syndrome (BMS) showed higher salty scores (p = 0.017). Patients who experienced exposure to toxic chemicals exhibited worse salty scores (p = 0.024). We conclude that gustatory dysfunction is associated with older age, male sex, and co-morbidities of major trauma, current chemotherapy, zinc deficiency, BMS, and exposure to toxins. The study highlights the importance of systemic evaluation and quantitive gustatory dysfunction assessment as part of the diagnostic process of patients with subjective complaints of taste disorders.

Comparison of prediction models for soy protein isolate hydrolysates bitterness built using sensory, spectrofluorometric and chromatographic data from varying enzymes and degree of hydrolysis

The bitterness of soy protein isolate hydrolysates prepared using five proteases at varying degree of hydrolysis (DH) and its relation to physicochemical properties, i.e., surface hydrophobicity (H0), relative hydrophobicity (RH), and molecular weight (MW), were studied and developed for predictive modelling using machine learning. Bitter scores were collected from sensory analysis and assigned as the target, while the physicochemical properties were assigned as the features. The modelling involved data pre-processing with local outlier factor; model development with support vector machine, linear regression, adaptive boosting, and K-nearest neighbors algorithms; and performance evaluation by 10-fold stratified cross-validation. The results indicated that alcalase hydrolysates were the most bitter, followed by protamex, flavorzyme, papain, and bromelain. Distinctive correlation results were found among the physicochemical properties, influenced by the disparity of each protease. Among the features, the combination of RH-MW fitted various classification models and resulted in the best prediction performance.

Characterization and Comparison of Extra Virgin Olive Oils of Turkish Olive Cultivars.

Extra virgin olive oils (EVOOs) obtained from five Turkish olive cultivars widely produced in the Aegean and Marmara regions were investigated based on their total antioxidant capacity (TAC), total phenolic content (TPC), pigment contents, fatty acid (FA) profiles, phenolic compounds (PC), volatile compounds (VC), and sensory properties. The results showed that all properties of EVOO samples were significantly affected by the olive cultivar used. The pigment contents in Ayvalık (9.90 mg·kg-1) and Uslu (9.00 mg·kg-1) oils were higher than the others (p < 0.05). The greatest values for oleic acid (74.13%) and TPC (350.6 mg·kg-1) were observed in Gemlik and Domat oils, respectively (p < 0.05). Edincik oil showed the maximum hydroxytyrosol content (48.022 mg·kg-1) and TAC value (515.36 mg TE·kg-1) (p < 0.05). The Edincik, Domat, and Uslu oils were significantly not different for the total content of C6 compounds derived by lipoxygenase, which are the main volatiles responsible for the typical aroma of EVOOs (p > 0.05). Domat oil also exhibited the highest scores for bitterness and pungency perceptions (p < 0.05). The fruitiness scores of the oil samples (except for Ayvalık oil) were close to each other, even if they were statistically different (p < 0.05). Principal component analysis (PCA) indicated that the Ayvalık oil was separated from the others due to its poor-quality characteristics. As a result, it can be stated that Domat olive oil has better quality than the others.

The application of waterless empirical taste test（WETT®） in 159 Chinese healthy subjects

Objective:This study examined the influences of age and gender on the taste function of a sizable sample of healthy Chinese subjects using the Waterless Empirical Taste Test（WETT®）, and provided scientific evidences for taste evaluation in clinic. Methods:A total of 159 subjects were tested based on strict inclusion and exclusion criteria. The 53 stimuli strips, presented on monomer cellulose pads, were designed to test 5 basic taste functions including sour, sweet, bitter, salty and umami of all subjects. The analysis was computed in SAS 9.4 statistical software. Results:The total taste score of the subjects was 35.00±8.94; the average test administration time was（21.61±7.80） min. The total test scores decreased across age categories（young group: 37.41±8.12, middle-aged group: 34.48±9.04, elderly group: 29.31±8.64）, the correlation coefficient between the total test scores and age was r=-0.335, P<0.05. There were significant differences in sour and bitter scores among different age groups（Psour=0.019, Pbitter<0.001）. Overall, women outperformed men on the total test（[36.53±8.72]vs[32.93±8.87], P=0.012）. There were correlations among individual taste of scores, and the correlation coefficient between umami and total score was the strongest（rumami/total=0.700，P<0.05）. Conclusion:This study demonstrated that a simple self-administered taste test, the WETT®, could be applied to Chinese healthy people. Age and gender-effects are the main factors which affect gustatory function.

Characteristics of Beef Patties Substituted by Different Levels of Textured Vegetable Protein and Taste Traits Assessed by Electronic Tongue System.

The main objective of this study was to incorporate soy-based textured vegetable protein (TVP) into beef patties in different quantities (10–40%) and compare various characteristics of these innovative formulations with a regular beef patty as a control. Incorporation of 10–40% TVP resulted in significantly lower (p < 0.05) moisture and fat contents, while higher crude fiber contents were detected compared to beef as the control. In addition, cooked patties showed higher pH levels (p < 0.05), with color coordinates expressing lighter, yellowish, and slightly redder indices than raw patties. Similarly, a plant protein that includes TVP minimizes (p < 0.05) WHC (water holding capacity), both RW% (release water) and CL% (cooking loss). Furthermore, hardness, cohesiveness, and thickness were reduced significantly (p < 0.05), while gumminess and chewiness increased (p < 0.05) considerably with the substitution of TVP (10–40%) compared to the control. Patties made without TVP received higher scores for sourness, bitterness, umami, and richness than the rest of the formulations. However, a higher tendency was detected for sourness, astringency, umami, and saltiness values with increasing additions of TVP. Nevertheless, hierarchical clustering revealed that the largest group of fatty acid profiles, including palmitoleic acid (C16:1), stearic acid (C18:0), and palmitic acid (C16:0), was slightly reduced with the addition of TVP, while arachidic acid (C20:0), lauric acid (C12:0), and oleic acid (C18:1) increased moderately with increasing levels of TVP. Meanwhile, the second-largest cluster that included linoleic acid (C18:2), arachidonic acid (C20:4), and linolenic acid (C18:3) increased enormously with higher levels of TVP incorporation. Taken together, it is suggested that incorporation of TVP up to 10–40% in beef patties shows promising results.

Effect of Functional Endoscopic Sinus Surgery on Gustatory Function in Patients With Chronic Rhinosinusitis.

In this study, we investigated the effect of functional endoscopic sinus surgery (FESS) on gustatory function in patients with chronic rhinosinusitis (CRS). Forty-three patients with CRS who underwent FESS were included in this study. Prior to FESS and 3 months after surgery, the severity of rhinosinusitis was assessed using the Taiwanese version of the 22-item SNOT (SNOT-22), endoscopic examination, and acoustic rhinometry. The olfactory function was evaluated using the phenylethyl alcohol odor detection threshold test and the traditional Chinese version of the University of Pennsylvania Smell Identification Test, and the gustatory function was evaluated using the whole mouth suprathreshold taste test (WMTT) and the taste quad test (TQT). Subgroup analyses were performed based on CRS phenotypes and endotypes. The SNOT-22 significantly improved 3 months after FESS for all patients with CRS. The endoscopic score and olfactory function significantly improved in patients with eosinophilic CRS and in patients with nasal polyps (CRSwNP). The WMTT sweet and bitter scores were significantly lower after FESS in CRSwNP, but the TQT sweet score was significantly higher in patients without nasal polyps. In addition, patients with noneosinophilic CRS had significantly decreased WMTT and salty scores 3 months after FESS. Our results showed that the effect of FESS on gustatory function of patients with CRS was different with the different testing procedures, the association with nasal polyps, and the underlying inflammatory patterns.

Beef Protein-Derived Peptides as Bitter Taste Receptor T2R4 Blockers.

The aim of this work was to determine the T2R4 bitter taste receptor-blocking ability of enzymatic beef protein hydrolysates and identified peptide sequences. Beef protein was hydrolyzed with each of six commercial enzymes (alcalase, chymotrypsin, trypsin, pepsin, flavourzyme, and thermoase). Electronic tongue measurements showed that the hydrolysates had significantly ( p < 0.05) lower bitter scores than quinine. Addition of the hydrolysates to quinine led to reduced bitterness intensity of quinine with trypsin and pepsin hydrolysates being the most effective. Addition of the hydrolysates to HEK293T cells that heterologously express one of the bitter taste receptors (T2R4) showed alcalase, thermoase, pepsin, and trypsin hydrolysates as the most effective in reducing calcium mobilization. Eight peptides that were identified from the alcalase and chymotrypsin hydrolysates also suppressed quinine-dependent calcium release from T2R4 with AGDDAPRAVF and ETSARHL being the most effective. We conclude that short peptide lengths or the presence of multiple serine residues may not be desirable structural requirements for blocking quinine-dependent T2R4 activation.

Do healthy diets differ in their sensory characteristics?

The relationship between sensory characteristics of foods, diets and weight status is not well established. However, such knowledge could assist in better understanding food choices and inform strategies to improve diet quality. The objectives of this study were to examine the sensory characteristics of diets varying in healthiness and to explore differences by demographics, weight status and diet quality.Data were captured using the online CSIRO Healthy Diet Score survey, including 38 questions on the frequency and quantity of foods consumed, facilitating the calculation of an overall diet quality score out of 100. Data from 145,975 Australian adults are reported.Sensory characteristics of 105 foods and beverages representative of the survey’s food groups were described using a trained sensory panel in terms of basic tastes, fatty mouthfeel and flavour strength. Average sensory scores (weighted by frequency of consumption) were calculated for each food group question. Reported intake (in serves) was multiplied by the sensory scores for each food group consumed to estimate the total sensory value of the diet.Higher diet quality was associated with higher sweet and bitter scores, but a greater proportion of this sweetness was from healthy core foods rather than discretionary foods. Salty taste tended to be lower in diets of higher quality, and there were no differences in fatty mouthfeel by diet quality. Overall flavour intensity increased with diet quality.For the first time the sensory characteristics of foods pertaining to recommended healthy diets can be described. Consumers, industry and public health could utilise such knowledge to encourage the adoption of higher quality diets.

겨우살이 추출물 첨가 양갱의 품질특성 및 항산화활성

This study was conducted to assess the quality characteristics and antioxidant activity of yanggaeng prepared with different concentrations of Viscum album extracts (VAE; 0, 1, 3 and 5%). The moisture content ranged from 37.85% to 39.38%, exhibiting no significant differences between the groups. The pH level of VAE 5% added yanggaeng was the lowest, followed in order by 3% and 1% additions. Increasing the amount of VAE in yanggaeng tended to increase acidity. The lightness value of the Hunter color system decreased based on the amount of VAE concentrate added to yanggaeng. As VAE content increased, changes in hardness, gumminess, and brittleness were all significant (p<0.05). Characteristics of cohesiveness and springiness showed no significant differences. Total polyphenol content was the highest in VAE 5% added yanggaeng. Antioxidant activities such as DPPH radical scavenging activity of the control group was 2.29%, whereas groups with added VAE ranged from 7.52~28.05%. As VAE increased, antioxidative activity also increased. In the sensory evaluation, yanggaeng addition with VAE 3% had excellent scores for bitterness, moistness, and overall acceptability. Yanggaengs with moderate levels of VAE 3% are recommended (with respect to overall preference score) to take advantage of the functional properties of VAE without sacrificing consumer acceptability.

Thyroid Hormone Replacement Therapy Improves Olfaction and Taste Sensitivity in Primary Hypothyroid Patients: A Prospective Randomised Clinical Trial.

Smell and taste are known to be influenced by thyroid function changes. However, many hypothyroid patients and physicians are unaware of their dysosmia and dysgeusia. The present study was performed to shed more light on the relation between hypothyroidism and olfactory loss. 32 primary hypothyroid patients and 31 controls enrolled in the prospective randomized interventional study. Newly diagnosed Primary hypothyroid patients were treated with L-thyroxine for 3-6 months. The control group was selected on the basis of the biochemical evidence of a normal thyroid function. Psychophysiological olfactory testing was performed using odor dispensers similar to felt-tip pens ("Sniffin' Sticks", Burghart, Wedel, Germany). Taste function tests were made using "Taste Strips" (Burghart, Wedel, Germany) which are basically tastant adsorbed filter paper strip. Smell identification, threshold, discrimination, TDI scores, bitter and sweet taste scores were significantly lower in untreated hypothyroid patients compared to controls (12.31±1.09 vs. 14.03±1.05, p<0.001; 7.09±1.15 vs. 8.89±1.12, p<0.001; 11.47±0.95 vs. 13.06±0.85, p<0.001; 30.90±2.70 vs. 35.89±2.07, p<0.001; 4.88±1.6 vs. 6.64±0.96, p<0.001; and 5.5±2.22 vs. 6.58±1.28, p=0.021) respectively. Comparison of scores at the third month of treatment and before treatment of hypothyroid patients revealed significant improvement in smell and taste functions in terms of identification, threshold, discrimination, TDI scores, bitter, sweet and salty tastes (12.31±1.09 vs. 13.84±1.22, p<0.001; 7.09±1.15 vs. 8.02±1.16, p<0.001; 11.47±0.95 vs. 12.41±1.21, p<0.001; 30.90±2.70 vs. 34.27±3.25, p<0.001; 4.88±1.6 vs. 6.06±1.4, p<0.001; 5.5±2.22 vs. 6.38±1.28, p<0.001; and 6.12±2.32 vs. 6.62±1.48, p=0.044) respectively. On correlation analysis, there was a negative correlation between TPO-Ab levels and discrimination, identification and TDI scores (r=-0.409, p=0.02; r=-0.424, p=0.016; r=-0.532, p=0.002), and also between Tg-Ab levels and identification, TDI, and bitter scores (r=-0.423, p=0.016; r=-0.468, p=0.007; r=-0.409, p=0.02) respectively. Primary hypothyroidism was found to have a negative effect on smell and taste. RAI treatment was found to be most destructive on smell and taste compared to surgical and autoimmune hypothyroidism. Treatment of hypothyroidism was positively correlated with an improvement of both senses. Thus, the future workup of patients with smell/taste loss should include investigations for thyroid functions.

Aroma and flavour properties of Saskatchewan grown field peas (Pisum sativum L.)

Malcolmson, L., Frohlich, P., Boux, G., Bellido, A-S., Boye, J. and Warkentin, T. D. 2014. Aroma and flavour properties of Saskatchewan grown field peas (Pisum sativum L.). Can. J. Plant Sci. 94: 1419–1426. The aroma and flavour properties of cooked field peas (Pisum sativum L.) were evaluated by a trained sensory panel. Two to four cultivars within four market classes of pea (yellow, green, marrowfat and dun) grown in two locations in Saskatchewan over 2 crop years were evaluated. Panelists found the greatest differences in aroma and flavour properties among market classes, although significant differences were also found among crop year for the aroma attributes of cooked vegetable, earthy, brothy, grainy, hay-like and metallic and the flavour attributes of pea and bitterness. There was also a significant cultivar by crop year interaction for metallic and pea flavor. Dun peas had low intensity scores for sweetness, bitterness and pea flavour. Both green and marrowfat peas had high intensity scores for sweetness and pea flavour. Green peas also had high intensity scores for pea, cooked vegetable, earthy and metallic aroma. Yellow peas had high intensity scores for pea flavour and pea, cooked vegetable and earthy aroma. Differences were found among the four cultivars of yellow peas for bitterness, pea flavour, and pea and earthy aroma. For green peas, differences were found among the three cultivars for pea flavour and aroma. The only difference found among the two cultivars of marrowfat peas was for sweetness. No differences were found between the two cultivars of dun peas. For all pea market classes, milder flavour and aroma may be beneficial in some whole pea or pea flour applications.

감과피 분말을 첨가한 쿠키의 품질특성

Traditionally, the persimmon Gojongsi (Diospyros kaki Thunb) is peeled to make dried persimmons and the skins are thrown away. In this study, the quality characteristics of cookies containing persimmon peel powder were tested for recycling of the persimmon peels. The amounts of persimmon peel powder added to the cookies were about 0, 5, 7, 9 and 11%. The densities of the cookies of the control group and the persimmon peel powder containing experimental group were 1.25 and 1.25~1.37 respectively. The pH was 6.02 for the control group and 5.95~6.01 for the experimental group. Significant differences in the moisture content were observed between groups at 3.34 and 2.16~3.31 for the control and experimental groups, respectively (p<0.05). The spreadabilities and loss rates of the cookies increased with increasing amounts of persimmon peel powder (p<0.05). In contrast, the loss rates and leavening rate of the cookies decreased significantly with decreasing amounts of persimmon peel powder (p<0.05). The lightness of the cookies showed significant decrease (p<0.05), while the redness and yellowness increased with increasing amounts of persimmon peel powder. The hardness (kg) of the control group was 0.847 while that of the experimental group was 0.904~1.110. In the QDA, the results of sensory characteristic analysis showed that the experimental group earned 11% higher scores for color, flavor, taste, and bitterness, 7% higher for appearance and 9% higher for after taste. The consumer acceptance test revealed the experimental group to have a 7% more positive evaluation for color, favor, taste and texture than the control group. On the grounds of the experiment above, the optimal mixture ratio from the sensory test was found to be 7% persimmon peel powder in the cookies.

Sensory preferences among general Japanese consumers and physicochemical evaluation of deep-fried peanuts

The development of food that satisfies consumer preferences is very important for producing commodities. In the present study, 132 Japanese consumers carried out sensory evaluation of deep-fried peanuts with varying frying times (2, 4, 6, 9, 12 and 15 min) at 150 °C, and the relationships among sensory elements and physicochemical properties were investigated. The sensory scores for colour, bitterness, and deep-fried peanut aroma increased (darker or stronger) with frying time, whereas the sweetness score was relatively high (strong) for frying times of 2, 4, 6 and 9 min, and then decreased (weaker) with increasing frying time. Frying times of 4, 6 and 9 min scored higher in overall liking than other times. Multiple-regression analysis indicated that the overall liking score was positively correlated with sweetness (standardised regression coefficient, β = +0.51) and deep-fried peanut aroma (β = +0.26) scores but negatively correlated with bitterness score (β = -0.25). Multiple-regression analysis also indicated a difference in sensory preference by gender. Sensory elements were closely related to the physicochemical properties, including the colour indexes (CIELAB colour space) and the sucrose and water contents. When L(*) (CIELAB colour space, lightness index) was 53-64 and water content was 10-30 g kg(-1), the mean overall liking score was relatively high implying acceptable fried peanut quality. Relationships among individual sensory elements were confirmed. Multiple-regression analysis indicated a strong positive correlation between sweetness and overall liking and a small difference in sensory preference by gender. Sensory evaluations can thus be expressed by physicochemical properties.

Effect of ethylene and 1-methylcyclopropene on bitter compounds in carrots (Daucus carota L.)

Sensory appearance of carrots is determined by a multiplicity of compounds, while a specific bitter taste depends on the content of phenolics including isocoumarins, polyacetylenes, and terpenes, being modulated by sugar content. Since exposure of carrots to ethylene may cause a bitter taste, the compounds potentially contributing to ethylene-induced bitterness were investigated. Storage roots of 3 carrot cultivars were stored in the dark for 7d at 17°C under aeration with and without added 7–10μLL−1 ethylene, and an aliquot was pre-treated with 1-methylcyclopropene (1-MCP) to inhibit the effect of ethylene. Accumulation of 6-methoxymellein (6-MM), total phenolics, polyacetylenes, terpenoid volatiles, and sugars was monitored, and sensory analysis was performed by a trained panel. Ethylene enhanced the accumulation of 6-MM and other phenolics, but partially inhibited the accumulation of terpenoid volatiles. However, the increase of polyacetylene levels during storage was found to be independent of ethylene treatment. In general, accumulation of 6-MM was inhibited after pre-treatment with 1-MCP. While the respiration rate of carrots was stimulated by ethylene, total sugar content during storage remained unchanged. Sensory profiling and principal component analysis revealed a close relationship between 6-MM content and other phenolics with ethylene-induced bitterness of carrots, whereas contents of the predominant polyacetylene falcarindiol and terpenoids were related to the characteristic carrot, but not bitter, taste. Pre-treatment of carrots with 1-MCP resulted in significantly lower sensory scores for bitterness of ethylene-exposed carrots compared to carrots without 1-MCP treatment. In conclusion, the results strongly suggest that ethylene-induced bitterness of carrots primarily results from the accumulation of 6-MM accompanied by further phenolics, while terpenoid and polyacetylene levels did not substantially contribute.

Development of a novel Zn fortified table olive product

This work explores novel Zn fortified table olive presentations, using “Aceituna Aloreña de Málaga” as the model matrix. The addition of ZnCl2 to the packing brine led to novel products with limited changes in colour and improved instrumental firmness. Partial Least Square (PLS) analysis linked the physicochemical characteristics and the sensory scores to the products, allowing for their characterization. The control had the highest scores for saltiness and bitterness as well as for the kinaesthetic sensations. The addition of 0.50 g/L ZnCl2 led to a product with average physicochemical and sensory characteristics. The product added with 0.75 g/L ZnCl2 had the highest titratable acidity and acid scores and the lowest pH while showing average values for the other variables. The olives prepared with 1.00 g/L ZnCl2 produced a presentation with high firmness and Zn content in flesh but the lowest scores for the kinaesthetic sensations, bitterness and saltiness. Overall, the product with 0.75 g/L ZnCl2 in the packing brine could be a good potential for novel Zn fortified table olive presentations. The consumption of 10 olives (50 g of flesh) of these fruits would supply around 79% of the recommended daily intake of Zn (or ∼12% in 15 g of an olive flesh serving size).

Prospective, Randomized, Pilot Study Evaluating the Effect of Ice Chips Administration versus None on the Bitterness of Crushed Medications in Postoperative Bariatric Patients

Background: Providing bariatric patients medications postoperatively is challenging. Research is warranted to determine a method to improve patient perception of crushed medication bitterness and/or taste. Purpose: The purpose of this study was to test whether a nursing intervention of administering ice chips to postoperative bariatric patients' tongues before and after administering crushed medications would result in improved patient perception of bitterness and/or taste. Methods: In this pilot, prospective study, 100 adult subjects were randomized to either the intervention group (ice chips intervention) or the control group (no ice chips). Intervention-group subjects provided pre- and post-ice scores for bitterness and taste on a validated 5-point categorical scale (bitterness: 1 = “least bitter,”, 2 = “less bitter,” 3 = “neutral,” 4 = “more bitter,” 5 = “most bitter”; taste: 1 = “least unpleasant,” 2 = “less unpleasant,” 3 = “neutral,” 4 = “more unpleasant,” 5 = “most unpleasant”). Control-group subjects provided ratings after medication administration only. The Institutional Review Board approved this study. Subjects provided informed consent. Results: Fifty subjects were in each study group, and the majority were female Caucasians. In the intervention group, as a result of the ice chips intervention, there was a 1.16-point mean reduction in bitterness (3.66 to 2.62; t = 5.32, p < 0.0001) and a 1.04 improvement in taste (3.86 to 2.70; t = 4.72, p < 0.0001). Conclusions: The hypothesis of this study was met, as the ice chips intervention procedure provided to patients before and after crushed medication administration significantly improved bitterness and taste. Nurses can implement this procedure to improve bariatric patient medication experiences postoperatively.

Enzymatic Modification of Saponins from Platycodon grandiflorum with Aspergillus niger

Platycodon grandiflorum A. DC (Campanulaceae) is a traditional medicinal plant. Its root, Platycodi Radix, contains an abundant amount of saponin glycosides, platycodins, of which platycodin D is one of the major components. The chemical structures of platycodins can be modified by various types of chemical processing, but a modification mediated with microorganisms has been not reported yet. In this study, platycodin D was modified to several partially degraded platycodin glycosides after treatment with a crude enzyme extract from Aspergillus niger (A. niger). The modified platycodin D possessed a shorter sugar side-chain, and presented a remarkably reduced V79-4 cell (Chinese hamster lung fibroblasts) cytotoxicity and erythrocyte hemolytic toxicity, whereas the nitrite-scavenging activity was increased in the modified platycodin D. Sensory scores for pungency, bitterness and after-taste were improved as well in the modified platycodin D. Results suggest that A. niger mediated modification yielded a novel partially degraded platycodin glycoside which possesses increased bioactivities and improved sensory values, yet with reduced toxic profiles.

Proteolysis of Hispánico Cheese Manufactured Using Lacticin 481-Producing Lactococcus lactis ssp. lactis INIA 639

Hispánico cheese was manufactured using lacticin 481-producing Lactococcus lactis ssp. lactis INIA 639, bacteriocin-nonproducing L. lactis ssp. lactis INIA 437, or a combination of both strains, as starter cultures. Lactobacillus helveticus LH 92, a culture of high amino-peptidase activity sensitive to lacticin 481, was added to all vats. Milk inoculation with the bacteriocin producer promoted early lysis of Lb. helveticus cells in cheese. Cell-free aminopeptidase activity in cheese made with the 3 lactic cultures was 1.8 times the level reached in cheese made only with L. lactis strain INIA 437 and Lb. helveticus, after 15 d of ripening. Proteolysis (as estimated by the o-phthaldialdehyde method) in cheese made with the 3 lactic cultures was twice as high, and the level of total free amino acids 2.4 times the level found in cheese made only with L. lactis strain INIA 437 and Lb. helveticus, after 25 d of ripening. Hydrophobic and hydrophilic peptides and their ratio were at the lowest levels in cheese made with the 3 lactic cultures, which received the lowest scores for bitterness and the highest scores for taste quality.

Effect of chymosin reduction and salt substitution on the properties of white salted cheese

Abstract A whey salts mixture was used as a partial substitute for sodium chloride to provide a modified Na:K ratio (1:3.4) in the manufacture of white salted cheese using ultrafiltration. Reduction of chymosin addition from 20 to 8 μL kg −1 of cheese was also investigated. Variation of salt and chymosin levels did not result in any significant differences in composition and physicochemical properties. The rates of proteolysis in terms of water-soluble nitrogen (WSN) and nitrogen soluble in 12% trichloroacetic acid (TCA-SN) were affected by chymosin levels but not by salt treatment. Urea-PAGE electrophoretic analysis of caseins from the cheeses manufactured using three levels of chymosin and two salt types showed that the hydrolysis of α s1 -casein was higher than for β -caseins but the differences between the cheeses were not significant ( P > 0.05 ) . The chymosin level did not have a significant effect ( P > 0.05 ) on hardness and fracturability, suggesting that any variation in hardness due to the initial hydrolysis was being confounded by other variables. Cheeses including the whey salts product were harder and more fracturable ( P 0.01 ) than the cheese treated with NaCl only. Both hardness and fracturability values decreased ( P 0.05 ) over the maturation period. The scores for bitterness were low; neither the effects of salt nor chymosin levels were significant ( P > 0.05 ) .

Effects of Standardization of Whole Milk with Dry Milk Protein Concentrate on the Yield and Ripening of Reduced-Fat Cheddar Cheese

Commercial milk protein concentrate (MPC) was used to standardize whole milk for reduced-fat Cheddar cheesemaking. Four replicate cheesemaking trials of three treatments (control, MPC1, and MPC2) were conducted. The control cheese (CC) was made from standardized milk (casein-to-fat ratio, C/F ∼1.7) obtained by mixing skim milk and whole milk (WM); MPC1 and MPC2 cheeses were made from standardized milk (C/F ∼1.8) obtained from mixing WM and MPC, except that commercial mesophilic starter was added at the rate of 1% to the CC and MPC1 and 2% to MPC2 vats. The addition of MPC doubled cheese yields and had insignificant effects on fat recoveries (∼94% in MPC1 and MPC2 vs. ∼92% in CC) but increased significantly total solids recoveries (∼63% in CC vs. 63% in MPC1 and MPC2). Although minor differences were noted in the gross composition of the cheeses, both MPC1 and MPC2 cheeses had lower lactose contents (0.25 or 0.32%, respectively) than in CC (0.60%) 7 d post manufacture. Cheeses from all three treatments had ∼109 cfu/g initial starter bacteria count. The nonstarter lactic acid bacteria (NSLAB) grew slowly in MPC1 and MPC2 cheeses during ripening compared to CC, and at the end of 6 mo of ripening, numbers of NSLAB in the CC were 1 to 2 log cycles higher than in MPC1 and MPC2 cheeses. Primary proteolysis, as noted by water-soluble N contents, was markedly slower in MPC1 and MPC2 cheeses compared to CC. The concentrations of total free amino acids were in decreasing order CC>MPC2>MPC1 cheeses, suggesting slower secondary proteolysis in the MPC cheeses than in CC. Sensory analysis showed that MPC cheeses had lower brothy and bitter scores than CC. Increasing the amount of starter bacteria improved maturity in MPC cheese.