106. The Role of Rennet in the Ripening of Cheddar Cheese

1935 ◽  
Vol 6 (2) ◽  
pp. 204-217 ◽  
Author(s):  
I. R. Sherwood

Attempts were made to eliminate the bacterial factor in Cheddar cheeseripening, through the agency of chloroform, and an assessment of the role of rennet was thus rendered possible.After investigating the effect of chloroform and toluene upon the proteolytic action of rennet and trypsin in milk, the results obtained were applied in studies upon the ripening of cheese in the presence of chloroform. Cheese of normal manufacture was chloroformed at the salting stage or one week or more after manufacture (when the curd had lost its rubbery nature and the germicide was more easily incorporated). Owing to the weakened activity of enzymes in the presence of germicides, it was necessary to employ larger proportions than usual of rennet, measured additions generally being made at the time when the chloroform was added. Under these conditions the general course of protein degradation, as measured by determinations of soluble nitrogen and non-protein nitrogen, was found to be identical with that occurring in normal control cheeses. Strong evidence was thus afforded that rennet is the only important agent attacking cheese protein during the ripening process.In the partition between the non-protein constituents of the normal and chloroformed cheeses, respectively, there were observed definite differences which tended to remain constant over the greater part of the ripening period. The relatively higher proportion of subpeptone nitrogen in the normal cheese was shown to be due, at least in some measure, to bacterial action.Cheese ripened in the presence of chloroform developed no volatile acid, and no cheese flavour could be detected.

1952 ◽  
Vol 30 (1) ◽  
pp. 50-66 ◽  
Author(s):  
D. W. A. Roberts

The respiratory rate, soluble nitrogen content, protein nitrogen content, water content, reducing sugar content, and sucrose content of each of the four quarters of the first leaf of Khapli Emmer wheat have been determined for plants grown with different soil water supplies. Under dry conditions the first leaf of wheat contains a higher concentration of nitrogenous substances than it does under moist conditions. The water content of the first leaf of wheat grown in dry soil or very wet soil is lower than it is for leaves grown in moderately moist soil. The significance of these two observations is discussed. Further support has been obtained for the view that the concentration of none of the substances determined is solely responsible for the respiratory rates and gradients observed in the leaves. The role of leaf anatomy in controlling and producing the observed respiratory gradients is discussed.


2021 ◽  
Vol 35 (1) ◽  
pp. 35-42
Author(s):  
José Luis Marcos ◽  
Azahara Marcos

Abstract. The aim of this study was to determine if contingency awareness between the conditioned (CS) and unconditioned stimulus (US) is necessary for concurrent electrodermal and eyeblink conditioning to masked stimuli. An angry woman’s face (CS+) and a fearful face (CS−) were presented for 23 milliseconds (ms) and followed by a neutral face as a mask. A 98 dB noise burst (US) was administered 477 ms after CS+ offset to elicit both electrodermal and eyeblink responses. For the unmasking conditioning a 176 ms blank screen was inserted between the CS and the mask. Contingency awareness was assessed using trial-by-trial ratings of US-expectancy in a post-conditioning phase. The results showed acquisition of differential electrodermal and eyeblink conditioning in aware, but not in unaware participants. Acquisition of differential eyeblink conditioning required more trials than electrodermal conditioning. These results provided strong evidence of the causal role of contingency awareness on differential eyeblink and electrodermal conditioning.


1973 ◽  
Vol 74 (4) ◽  
pp. 769-774 ◽  
Author(s):  
Akira Yokoyama ◽  
Hiroshi Tomogane ◽  
Katuaki Ôta
Keyword(s):  

ABSTRACT A non-steroidal oestrogen antagonist, MER-25, was administered to cycling rats for elucidating the role of oestrogen in the surge of prolactin observed on the afternoon of pro-oestrus (POe). In animals injected with 20 mg of MER-25 intramuscularly on the afternoon (16.30 h) of the first day of dioestrus (D-1), the surge of prolactin was blocked while the level of prolactin on the afternoon of POe of these animals was significantly higher than that of the corresponding controls injected with oil. Ovulation was also blocked in these animals treated with the drug on the afternoon of D-l. On the other hand, treatment on the morning (10.30 h) of the 2nd day of dioestrus failed to prevent not only the surge of prolactin but also ovulation. These observations provide strong evidence for the view that oestrogen is responsible for the surge of prolactin on the afternoon of POe, and that the surge is accompanied by that of LH.


2011 ◽  
Vol 23 (10) ◽  
pp. 2632-2635 ◽  
Author(s):  
Evelina Fedorenko ◽  
Nancy Kanwisher

On the basis of their review of the literature, Rogalsky and Hickok [Rogalsky, C., & Hickok, G. The role of Broca's area in sentence comprehension. Journal of Cognitive Neuroscience, 23, 1664–1680, 2011] conclude that there is currently no strong evidence for the existence of “sentence-specific processing regions within Broca's area” (p. 1664). Their argument is based, in part, on the observation that many previous studies have failed to detect an effect in the left inferior frontal regions for contrasts between sentences and linguistically degraded control conditions (e.g., lists of unconnected words, lists of nonwords, or acoustically degraded sentence stimuli). Our data largely replicate this lack of activation in inferior frontal regions when traditional random-effects group analyses are conducted but crucially show robust activations in the same data for the same contrasts in almost every subject individually. Thus, it is the use of group analyses in studies of language processing, not the idea that sentences robustly activate frontal regions, that needs to be reconsidered. This reconsideration has important methodological and theoretical implications.


1958 ◽  
Vol 36 (2) ◽  
pp. 227-235 ◽  
Author(s):  
Enrique Santamarina

The incidence of melanin in the bovine pineal gland was studied in 880 glands. Spectrophotometric analysis and chemical and cytochemical methods identified the black pigment present in the bovine pineal gland as melanin. No melanin was found in bulls 4 and 5 years of age nor in heifers of about 18 months. In pregnant cows over 5 years of age melanin was found in 5.4% of the pineal glands. Non-pregnant cows of the same age exhibited melanin in 8.5% of the pineal glands. Castrated male cattle between 18 and 24 months of age showed 49.6% of the pineal glands with macroscopical signs of melanization. As much as 67% of the pineal glands of steers from some herds contained melanin. In intact cattle melanin in the pineal appears to be mainly an aging phenomenon. The fact that castration in male cattle causes hypertrophy of the pineal gland followed by a degenerative process in which melanin is involved seems to give strong evidence of a pineal gonadal interrelationship. The possible role of the hormones in the phenomenon of melanin formation is discussed.


2020 ◽  
Vol 123 (2) ◽  
pp. 451-453
Author(s):  
Joshua A. Seideman

We make a saccadic eye movement once every few hundred milliseconds; however, the neural control of saccade execution is not fully understood. Dynamic, moment-by-moment variations in saccade velocity are typically thought to be controlled by neurons in the lower, but not the upper regions of the brainstem. In a recent report, Smalianchuk et al. (Smalianchuk I, Jagadisan UK, Gandhi NJ. J Neurosci 38: 10156–10167, 2018) provided strong evidence for a role of the superior colliculus, a midbrain structure, in the instantaneous control of saccade velocity, suggesting the revision of long-standing models of oculomotor control.


2020 ◽  
Vol 10 (1) ◽  
pp. 4966-4971

The role of liposome encapsulated flavourzymes on the ripening acceleration of Iranian white brined cheese has been studied. Liposomal enzymes (made by heating method) had a better performance than free enzymes, resulting in cheeses with lower total solid content and a higher concentration of soluble nitrogen (pH 4.6 and 12.5% trichloroacetic acid) through the ripening period (30 days at 12 oC). The ripening time could be shortened for 10 to 20 days. The entrapment efficiency and diameter of the liposomal enzyme were 26.5% and 189 nm, respectively. The proposed technology could be a potential treatment for the acceleration of Iranian white brined cheeses ripening.


2021 ◽  
pp. 157-165
Author(s):  
Mark Robert Rank ◽  
Lawrence M. Eppard ◽  
Heather E. Bullock

Chapter 19 reviews why, despite strong evidence to the contrary, the poverty myths continue to exist. Two sets of factors are examined—psychologically based factors and sociologically based factors. Psychological factors include particular personality traits, system justification, the use of stereotypes, confirmation bias, and attribution errors. Sociological factors include an understanding of who in society benefits from the existence of these myths. They include political actors, the affluent, and society as a whole. Summoning a newfound willingness to interrogate the role of individualism and meritocracy in shaping our attitudes toward each other and the distribution of resources is likely to prove especially difficult. Changing the paradigm toward one based on fact and reality moves us closer to effectively addressing and alleviating poverty.


Endocrinology ◽  
2012 ◽  
Vol 153 (11) ◽  
pp. 5105-5118 ◽  
Author(s):  
Robert L. Goodman ◽  
Michael N. Lehman

Abstract The discovery that kisspeptin was critical for normal fertility in humans ushered in a new chapter in our understanding of the control of GnRH secretion. In this paper, we will review recent data on the similarities and differences across several mammalian species in the role of kisspeptin in reproductive neuroendocrinology. In all mammals examined to date, there is strong evidence that kisspeptin plays a key role in the onset of puberty and is necessary for both tonic and surge secretion of GnRH in adults, although kisspeptin-independent systems are also apparent in these studies. Similarly, two groups of kisspeptin neurons, one in the arcuate nucleus (ARC) and the other more rostrally, have been identified in all mammals, although the latter is concentrated in a limited area in rodents and more scattered in other species. Estrogen has divergent actions on kisspeptin expression in these two regions across these species, stimulating it the latter and inhibiting expression in the former. There is also strong evidence that the rostral population participates in the GnRH surge, whereas the ARC population contributes to steroid-negative feedback. There may be species differences in the role of these two populations in puberty, with the ARC cells important in rats, sheep, and monkeys, whereas both have been implicated in mice. ARC kisspeptin neurons also appear to participate in the GnRH surge in sheep and guinea pigs, whereas the data on this possibility in rodents are contradictory. Similarly, both populations are sexually dimorphic in sheep and humans, whereas most data in rodents indicate that this occurs only in the rostral population. The functional consequences of these species differences remain to be fully elucidated but are likely to have significance for understanding normal neuroendocrine control of reproduction as well as for use of kisspeptin agonists/antagonists as a therapeutic tool.


Sign in / Sign up

Export Citation Format

Share Document