Skip to main content
Ch.16 Amino Acids, Proteins, and Enzymes
Timberlake - Chemistry: An Introduction to General, Organic, and Biological Chemistry 14th Edition
Timberlake14th EditionChemistry: An Introduction to General, Organic, and Biological ChemistryISBN: 9781292472249당신이 사용하는 게 아니라요?교과서 변경
16장, 문제 58a

Fresh pineapple contains the enzyme bromelain that hydrolyzes peptide bonds in proteins.
<IMAGE>
a. The directions for a gelatin (protein) dessert say not to add fresh pineapple. However, canned pineapple where pineapple is heated to high temperatures can be added. Why?

검증된 단계별 안내
1
Understand the problem: The question is asking why fresh pineapple cannot be added to a gelatin dessert, but canned pineapple can. This involves understanding the role of the enzyme bromelain and how it interacts with proteins in gelatin.
Step 1: Recall that bromelain is an enzyme found in fresh pineapple. Enzymes are biological catalysts that speed up chemical reactions, and bromelain specifically hydrolyzes (breaks down) peptide bonds in proteins.
Step 2: Gelatin is a protein derived from collagen. When gelatin is dissolved in water and cooled, it forms a gel-like structure due to the interaction of its protein molecules. If bromelain is present, it will hydrolyze the peptide bonds in gelatin, breaking down the protein structure and preventing the gel from forming.
Step 3: Canned pineapple is heated during the canning process. High temperatures denature enzymes, which means the bromelain in canned pineapple is inactivated. Denaturation alters the enzyme's structure, rendering it unable to catalyze the hydrolysis of peptide bonds.
Step 4: Since the bromelain in canned pineapple is denatured, it cannot break down the proteins in gelatin. This is why canned pineapple can be added to a gelatin dessert without affecting its ability to set, while fresh pineapple cannot.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
4m

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Bromelain

Bromelain is a proteolytic enzyme found in fresh pineapple that breaks down protein molecules by hydrolyzing peptide bonds. This enzymatic activity can prevent gelatin from setting properly, as it disrupts the protein structure necessary for the gelatin to solidify.

Gelatin

Gelatin is a protein derived from collagen, commonly used as a gelling agent in food products. It requires a specific temperature and pH to form a stable gel. The presence of bromelain in fresh pineapple can interfere with this process, leading to a failure in achieving the desired texture in gelatin desserts.

Heat Treatment

Canned pineapple undergoes heat treatment during processing, which denatures the bromelain enzyme, rendering it inactive. This means that when canned pineapple is added to gelatin, it does not affect the gelling process, allowing the dessert to set properly without the interference of the enzyme.
추천 영상:
관련 실천
교과서 질문

Adults who are lactose intolerant cannot break down the disaccharide in milk products. To help digest dairy food, a product known as Lactaid can be given prior to consuming dairy products. (16.4, 16.5)

b. What might happen to the enzyme if the Lactaid were stored at 55 °C?

35
views
교과서 질문

Adults who are lactose intolerant cannot break down the disaccharide in milk products. To help digest dairy food, a product known as Lactaid can be given prior to consuming dairy products. (16.4, 16.5)

a. What is the name of enzyme present in Lactaid, and what is the major class of this enzyme?

28
views
교과서 질문

Ethylene glycol (HO—CH2—CH2—OH) is a major component of antifreeze. If ingested, it is first converted to HOOC—CHO (oxoethanoic acid) and then to HOOC—COOH (oxalic acid), which is toxic.

<IMAGE>

b. The treatment for the ingestion of ethylene glycol is an intravenous solution of ethanol. How might this help prevent toxic levels of oxalic acid in the body?

730
views
교과서 질문

Identify the amino acids and type of interaction that occurs between the following R groups in tertiary protein structures:

c. —CH2—SH and HS—CH2

666
views
교과서 질문

Identify the amino acids and type of interaction that occurs between the following R groups in tertiary protein structures:

a.

720
views
교과서 질문

Fresh pineapple contains the enzyme bromelain that hydrolyzes peptide bonds in proteins.

<IMAGE>

b. Fresh pineapple is used in a marinade to tenderize tough meat. Why?

888
views