Microbes in Household Products Questions in English

(C) Lactic Acid Bacteria $(LAB)$ are a group of bacteria that grow in milk and convert it into curd.
During this process,they produce acids that coagulate and partially digest the milk proteins.
$LAB$ also play a significant role in improving the nutritional quality of milk by increasing the content of vitamin $B_{12}$.

(D) Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes.
$1$. Fish: Fermented fish products are common in many cultures,where microbes break down proteins to create unique flavors and preserve the food.
$2$. Soybean: Fermented soybean products like $Tempeh$,$Miso$,and $Soya$ sauce are widely produced using microbial fermentation.
$3$. Bamboo: Fermented bamboo shoots are a traditional food item in various regions,prepared by allowing lactic acid bacteria to ferment the shoots.
Since all these items can be processed through fermentation to create food products,the correct answer is $D$.

(B) $LAB$ (Lactic Acid Bacteria) such as $Lactobacillus$ grow in milk and convert it into curd.
During this process,they produce acids (specifically lactic acid) that coagulate and partially digest the milk proteins (casein).
This acidification process is responsible for the curdling of milk.

(D) Baker's yeast is the common name for the strain of yeast used in baking,which is scientifically known as $Saccharomyces \ cerevisiae$.
This yeast is used in the fermentation process to produce $CO_2$,which causes the dough to rise,making the bread soft and porous.

(A) The yeast used for making bread is $Saccharomyces \ cerevisiae$,which is commonly known as 'brewer's yeast' or 'baker's yeast'.
It performs fermentation,releasing $CO_2$ gas,which causes the dough to rise and makes the bread soft and porous.

(C) The process of converting milk into curd is carried out by Lactic Acid Bacteria $(LAB)$,such as Lactobacillus. These bacteria grow in milk and convert it into curd by producing acids that coagulate and partially digest the milk proteins.

(A) Baker's yeast is the common name for the strains of the yeast $Saccharomyces \ cerevisiae$ used in baking.
It acts as a leavening agent by fermenting the sugars present in the dough.
This process releases $CO_2$ and ethanol,which causes the bread dough to rise and become soft and spongy.

(B) The traditional drink 'toddy' is prepared by the fermentation of sap extracted from palm trees. In South India,this is a common beverage obtained from the sap of various species of palm trees,such as the Palmyra palm (Borassus flabellifer).

(A) The conversion of milk into curd is primarily carried out by Lactic Acid Bacteria $(LAB)$.
$Lactobacillus$ is the most common genus of bacteria that grows in milk and converts it into curd.
During this process,they produce acids that coagulate and partially digest the milk proteins $(casein)$.
This process also improves the nutritional quality of curd by increasing the content of Vitamin $B_{12}$.

(B) Lactic Acid Bacteria $(LAB)$ grow in milk and convert it into curd. During this process,they produce acids that coagulate and partially digest the milk proteins (casein). Additionally,$LAB$ also improve the nutritional quality of curd by increasing the content of Vitamin $B_{12}$.

(D) $LAB$ stands for Lactic Acid Bacteria.
$LAB$ such as Lactobacillus grow in milk and convert it into curd by producing acids that coagulate and partially digest the milk proteins.
In the preparation of dough for foods like dosa and idli,the fermentation process is carried out by bacteria,which results in the production of $CO_2$ gas,giving the dough a puffed-up appearance.
Therefore,$LAB$ and other bacteria are involved in the preparation of all these food items.

(B) The preparation of dosa and idli batter involves the process of fermentation. $LAB$ (Lactic Acid Bacteria) such as $Lactobacillus$ grow in the batter and produce lactic acid. This process of fermentation increases the volume of the batter,makes it fluffy,and improves its nutritional quality by increasing the content of Vitamin $B_{12}$.

(C) Toddy is a traditional drink of some parts of South India. It is made by fermenting sap from palms. The fermentation process is carried out by microorganisms,which convert the sugars present in the palm sap into alcohol and carbon dioxide.

(D) Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes.
In many cultures,various plant materials are fermented to enhance their nutritional value,flavor,and shelf life.
Soybean is widely fermented to produce products like tempeh,miso,and soy sauce.
Bamboo shoots are also commonly fermented in various Southeast Asian and Indian cuisines to create traditional food items.
Therefore,both soybean and bamboo are subjected to fermentation processes to produce food items.

(B) Silage is a type of fodder made from green foliage crops which has been preserved by acidification through fermentation. It is prepared by storing green plant tissues (like maize,sorghum,or grasses) in a silo where they undergo anaerobic fermentation by lactic acid bacteria. This process preserves the nutritional value of the fodder for cattle.

(A) Statement $S$ is true because microbes like $Lactic$ $Acid$ $Bacteria$ $(LAB)$ increase the nutritional quality of milk by increasing vitamin $B_{12}$ content,and other microbes improve texture and flavor.
Statement $R$ is true because $Roquefort$ cheese is ripened by growing a specific fungus,$Penicillium$ $roqueforti$,on it,which gives it a particular flavor.
Since the ripening of cheese by specific microbes is a direct example of how microbes improve the quality (flavor and texture) of food,$R$ is the correct explanation of $S$.

(A) $1$. $LAB$ (Lactic Acid Bacteria) such as $Lactobacillus$ grow in milk and convert it into curd.
$2$. During this process,they produce acids that coagulate and partially digest the milk proteins (casein).
$3$. Therefore,the production of acids by $LAB$ is the direct cause of the conversion of milk into curd.
$4$. Thus,both the statement and the reason are true,and the reason correctly explains the statement.

(C) The correct answer is $C$.
$A$. Pickles are preserved using lactic acid produced by bacteria.
$B$. Swiss cheese is ripened by the bacterium $Propionibacterium \text{ } sharmanii$.
$C$. Roquefort cheese is ripened by a specific fungus, $Penicillium \text{ } roqueforti$, not by bacteria. Thus, this is the mismatched option.
$D$. Ensilage is a method of preserving green fodder (plants) by fermentation.

(D) Lactic Acid Bacteria $(LAB)$,such as $Lactobacillus$,grow in milk and convert it into curd.
During this process,they produce acids that coagulate and partially digest the milk proteins.
$LAB$ also play a beneficial role in checking disease-causing microbes in our stomach.
Furthermore,$LAB$ significantly increase the nutritional quality of milk by increasing the content of Vitamin $B_{12}$ (Cyanocobalamin).

(B) The dough used for making $Dosa$ and $Idli$ is fermented by bacteria.
This fermentation process is primarily carried out by $Lactic$ $Acid$ $Bacteria$ $(LAB)$,such as $Leuconostoc$ and $Streptococcus$ species.
These bacteria produce carbon dioxide $(CO_2)$ during fermentation,which causes the dough to puff up or rise,giving the food its characteristic texture and flavor.

(C) The yeast used for making bread is commonly known as baker's yeast.
Its scientific name is $Saccharomyces \ cerevisiae$.
This yeast performs fermentation,which releases $CO_2$ gas.
The trapped $CO_2$ bubbles cause the dough to rise,making the bread soft and porous.

(A) Pickles are typically preserved through the process of lactic acid fermentation. During this process,lactic acid bacteria (such as $Lactobacillus$ species) convert sugars present in the vegetables into lactic acid. This acid lowers the $pH$ of the environment,which inhibits the growth of spoilage-causing microorganisms and preserves the food.

(C) $LAB$ stands for $Lactic$ $Acid$ $Bacteria$.
These bacteria grow in milk and convert it into curd.
During this process,they produce acids that coagulate and partially digest the milk proteins.

(D) $LAB$ (Lactic Acid Bacteria) performs several beneficial functions in the human body:
$1$. It converts milk into curd by producing acids that coagulate and partially digest the milk proteins.
$2$. It significantly improves the nutritional quality of curd by increasing the content of vitamin $B_{12}$.
$3$. In the human stomach,$LAB$ plays a beneficial role by checking disease-causing microbes and preventing infections.

(B) Roquefort cheese is ripened by growing a specific fungus called $Penicillium$ $roqueforti$ on it. This fungus gives the cheese its characteristic flavor and texture. Therefore,the correct option is $B$.

(B) The production of bread involves the process of fermentation. The yeast $Saccharomyces \ cerevisiae$,also known as brewer's yeast or baker's yeast,is used for this purpose. During fermentation,the yeast releases $CO_2$ gas,which makes the bread dough rise and gives it a porous,soft texture.

(D) Statement $P$ is true: Baker's yeast $(Saccharomyces \text{ } cerevisiae)$ is used in the baking industry to ferment dough,which releases $CO_2$ and makes the bread porous and soft.
Statement $Q$ is true: $LAB$ (Lactic Acid Bacteria) such as $Lactobacillus$ are added to milk to convert it into curd. $LAB$ plays a beneficial role in checking disease-causing microbes in our stomach and significantly increases the nutritional quality of curd by increasing vitamin $B_{12}$ content.

(C) Statement $P$ is incorrect because $LAB$ (Lactic Acid Bacteria) is used for curdling milk,while bread is made using Baker's yeast $(Saccharomyces \text{ } cerevisiae)$.
Statement $Q$ is correct because $Lactobacillus$ and other $LAB$ are used to convert milk into curd by producing acids that coagulate and partially digest the milk proteins.

(C) Lactic acid is produced by the fermentation of sugars by lactic acid bacteria $(LAB)$.
$Lactobacillus$ is the most common genus of bacteria used for this purpose.
These bacteria convert lactose (milk sugar) or other carbohydrates into lactic acid during the fermentation process.
Therefore,the correct option is $C$.

(D) $Lactobacillus$ bacteria,commonly known as Lactic Acid Bacteria $(LAB)$,grow in milk and convert it into curd.
$1$. During this process,they produce acids that coagulate the milk proteins (casein).
$2$. These acids also partially digest the milk proteins,making the curd more nutritious and easier to digest.
$3$. Furthermore,$LAB$ play a beneficial role in checking disease-causing microbes in our stomach and significantly improve the nutritional quality of curd by increasing the content of vitamin $B_{12}$.

(C) $LAB$ stands for Lactic Acid Bacteria.
$1$. $LAB$ grows in milk and converts it into curd.
$2$. During this process,they produce acids that coagulate and partially digest the milk proteins.
$3$. $LAB$ also plays a beneficial role in checking disease-causing microbes in our stomach.
$4$. Furthermore,$LAB$ increases the nutritional quality of curd by increasing the content of vitamin $B_{12}$.
Therefore,both statements $(A)$ and $(B)$ are correct.

(D) Microorganisms play a crucial role in the production of various food items through the process of fermentation.
$1$. Dosa and Idli are prepared from a batter that is fermented by bacteria like $Leuconostoc$ and $Streptococcus$ species.
$2$. Khaman and Dhokla are also fermented products where microorganisms help in leavening and improving the texture and flavor.
$3$. Curd and buttermilk are produced by the action of Lactic Acid Bacteria $(LAB)$ such as $Lactobacillus$ on milk,which coagulates and partially digests the milk proteins.
Therefore,all the listed food items involve the significant contribution of microorganisms.

(D) Microorganisms,particularly bacteria and fungi,are used in various industrial processes involving fermentation.
$1$. Traditional beverages like $Toddy$ (a traditional drink of some parts of southern India) are made by fermenting sap from palms.
$2$. Silage is produced by the fermentation of green fodder by lactic acid bacteria,which helps in preserving it for livestock.
$3$. Various food items like pickles and cheese are produced through the fermentation process using specific microbial cultures.
Therefore,all the mentioned products are produced through microbial fermentation.

(B) Toddy is a traditional drink of some parts of southern India. It is made by fermenting the sap drawn from palms. The process of fermentation is carried out by naturally occurring yeasts present in the sap,which convert the sugars in the sap into alcohol and carbon dioxide. Therefore,the correct process is fermentation.

$A$ is false because bread is made using Baker's yeast, which is $Saccharomyces \text{ cerevisiae}$, not $LBA$ (Lactic Acid Bacteria).
$R$ is true because $Lactobacillus$ (a type of Lactic Acid Bacteria) is used to ferment milk into curd by producing lactic acid, which coagulates and partially digests the milk proteins.

(D) $LAB$ (Lactic Acid Bacteria) such as Lactobacillus grow in milk and convert it into curd.
During this process,they produce acids that coagulate and partially digest the milk proteins.
$LAB$ is highly beneficial for the human digestive system as it improves nutritional quality by increasing Vitamin $B_{12}$.
In our stomach,$LAB$ plays a beneficial role by checking disease-causing microbes and protecting us from harmful bacteria.
Therefore,both statements $X$ and $Y$ are correct.

(C) The dough used for making foods like dosa and idli is fermented by bacteria. Specifically,the puffing-up appearance of the dough is due to the production of $CO_2$ gas by bacteria such as $Leuconostoc$ and $Streptococcus$ species. While yeast (a fungus) is used for bread making,the specific fermentation of dough for traditional Indian foods like dosa and idli is primarily attributed to bacteria.

(C) $LAB$ (Lactic Acid Bacteria) are beneficial bacteria that grow in milk and convert it into curd.
$1$. $LAB$ improves the nutritional quality of milk by increasing the content of vitamin $B_{12}$.
$2$. During the process of curd formation,$LAB$ produces acids that coagulate and partially digest the milk proteins (casein).
$3$. $LAB$ also plays a beneficial role in our stomach by checking disease-causing microbes.
$4$. $LAB$ does not digest lipids; it primarily acts on milk proteins. Therefore,the statement that they partially digest lipids is incorrect in the context of their primary function in milk.

(A) Pasteurization is a heat-treatment process primarily used to preserve milk and dairy products.
It involves heating the liquid to a specific temperature (e.g., $72^{\circ}C$ for $15$ seconds) to kill harmful microorganisms and extend the shelf life of the product without significantly altering its nutritional value or taste.

(B) Milk is the primary raw material used in the dairy industry for the production of various products such as curd,butter,cheese,and sweets. Through various fermentation and processing techniques,milk is converted into these diverse dairy products.

(B) The industrial processing of milk,including pasteurization and large-scale bottling,began in the late $19^{th}$ century. This period marked a significant shift in food technology,ensuring the safety and shelf-life of dairy products for urban populations.

(A) Statement $P$ is correct because milk is a primary source of nutrition for humans,providing essential proteins,fats,vitamins,and minerals.
Statement $Q$ is also correct because milk serves as a raw material for various dairy products like curd,butter,cheese,and sweets through fermentation and processing techniques.
Therefore,both statements are factually accurate.

(B) Toddy is a traditional alcoholic beverage commonly consumed in some parts of southern India.
It is prepared by the fermentation of sap extracted from various species of palm trees (family Arecaceae),such as the coconut palm ($Cocos$ $nucifera$) or the toddy palm ($Borassus$ $flabellifer$).
The natural sugars present in the sap are fermented by yeasts and bacteria to produce alcohol.
Therefore,the correct option is $B$.

(C) Toddy is a traditional drink of Southern India,which is correct as per statement $I$.
It is produced by the fermentation of sap from palm trees. However,this fermentation process is primarily carried out by naturally occurring yeasts,not bacteria. Therefore,statement $II$ is incorrect.
Thus,only statement $I$ is correct.

(B) Statement $(i)$ is incorrect because Dosa and Idli are fermented by bacteria (like $Leuconostoc$ and $Streptococcus$ species), not yeast.
Statement $(ii)$ is correct because $Saccharomyces \text{ } cerevisiae$ is commonly known as Brewer's yeast.
Statement $(iii)$ is correct because $LAB$ (Lactic Acid Bacteria) improve the nutritional quality of milk by increasing the content of vitamin $B_{12}$.
Statement $(iv)$ is incorrect because whisky and brandy are produced by distillation, whereas beverages like wine and beer are produced without distillation.
Therefore, statements $(ii)$ and $(iii)$ are correct.

(B) $Lactobacillus$ and other similar bacteria are collectively known as Lactic Acid Bacteria $(LAB)$.
These bacteria grow in milk and convert it into curd.
During this process,they produce acids that coagulate and partially digest the milk proteins.

(C) In the process of curd formation,a small amount of curd is added to fresh milk as a 'starter' or 'inoculum'.
This starter contains millions of Lactic Acid Bacteria $(LAB)$.
These bacteria grow in the milk and convert it into curd.
During this process,$LAB$ also improve the nutritional quality of the milk by increasing the content of vitamin $B_{12}$.

(B) Swiss cheese is ripened by the bacterium $Propionibacterium \text{ } sharmanii$.
During the fermentation process, this bacterium produces a large amount of $CO_2$ gas.
The accumulation of this $CO_2$ gas creates the characteristic large holes found in Swiss cheese.
Therefore, $a$ is $CO_2$ and $b$ is $Propionibacterium \text{ } sharmanii$.

(D) Microorganisms are used in the production of various food items through the process of fermentation.
$(I)$ Idli and $(II)$ Dosa are prepared from a batter that is fermented by bacteria (e.g.,Leuconostoc and Streptococcus species).
$(III)$ Toddy is a traditional drink made by fermenting sap from palms.
$(IV)$ Cheese is produced by the fermentation of milk by specific microorganisms like bacteria (e.g.,Propionibacterium sharmanii for Swiss cheese) or fungi (e.g.,Penicillium roqueforti for Roquefort cheese).
Therefore,all the listed items are produced through fermentation by microorganisms.

(A) Bread making involves the process of fermentation.
$Yeast$ (Saccharomyces cerevisiae) is added to the dough.
During fermentation,yeast breaks down the sugars present in the flour into ethanol and $CO_2$.
The release of $CO_2$ gas creates bubbles in the dough,which makes the bread porous and soft.